National Library of Energy BETA

Sample records for variable air-volume system

  1. Promising Technology: Variable-Air-Volume Ventilation System

    Broader source: Energy.gov [DOE]

    Variable-air-volume (VAV) ventilation saves energy compared to a constant-air-volume (CAV) ventilation system, mainly by reducing energy consumption associated with fans.

  2. Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit–Variable Air Volume and Air Handling Unit–Constant Air Volume Systems- 2014 BTO Peer Review

    Broader source: Energy.gov [DOE]

    Presenter: Jin Wen, Drexel University The goal of this project is to develop and demonstrate a library of diagnostics decision-support tools for medium-to-large-sized commercial buildings that use air handling unit (AHU) systems that can enable cost-effective diagnostics solutions (both embedded and add-on solutions) for existing buildings.

  3. Energy Savings for Occupancy-Based Control (OBC) of Variable-Air-Volume (VAV) Systems

    SciTech Connect (OSTI)

    Zhang, Jian; Lutes, Robert G.; Liu, Guopeng; Brambley, Michael R.

    2013-01-24

    This study evaluates the savings potential of occupancy based control (OBC) for large office buildings with VAV terminal boxes installed.

  4. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  5. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  6. High air volume to low liquid volume aerosol collector

    DOE Patents [OSTI]

    Masquelier, Donald A. (Tracy, CA); Milanovich, Fred P. (Lafayette, CA); Willeke, Klaus (Cincinnati, OH)

    2003-01-01

    A high air volume to low liquid volume aerosol collector. A high volume flow of aerosol particles is drawn into an annular, centripetal slot in a collector which directs the aerosol flow into a small volume of liquid pool contained is a lower center section of the collector. The annular jet of air impinges into the liquid, imbedding initially airborne particles in the liquid. The liquid in the pool continuously circulates in the lower section of the collector by moving to the center line, then upwardly, and through assistance by a rotating deflector plate passes back into the liquid at the outer area adjacent the impinging air jet which passes upwardly through the liquid pool and through a hollow center of the collector, and is discharged via a side outlet opening. Any liquid droplets escaping with the effluent air are captured by a rotating mist eliminator and moved back toward the liquid pool. The collector includes a sensor assembly for determining, controlling, and maintaining the level of the liquid pool, and includes a lower centrally located valve assembly connected to a liquid reservoir and to an analyzer for analyzing the particles which are impinged into the liquid pool.

  7. Demonstration of a Variable Phase Turbine Power System for Low...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Demonstration of a Variable Phase Turbine Power System for Low Temperature ...

  8. Two-Stage Variable Compression Ratio (VCR) System to Increase...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline ...

  9. Variable pressure power cycle and control system

    DOE Patents [OSTI]

    Goldsberry, Fred L.

    1984-11-27

    A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

  10. Production-Intent Lost-Motion Variable Valve Actuation Systems...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Production-Intent Lost-Motion Variable Valve Actuation Systems Production-Intent Lost-Motion Variable Valve Actuation Systems Variable valve actuation with onoff IEGR pre-bump is ...

  11. Compact, electro-hydraulic, variable valve actuation system providing

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    variable lift, timing and duration to enable high efficiency engine combustion control | Department of Energy Compact, electro-hydraulic, variable valve actuation system providing variable lift, timing and duration to enable high efficiency engine combustion control Compact, electro-hydraulic, variable valve actuation system providing variable lift, timing and duration to enable high efficiency engine combustion control Discusses development of advanced variable valve actuation system to

  12. Variable temperature seat climate control system

    DOE Patents [OSTI]

    Karunasiri, Tissa R.; Gallup, David F.; Noles, David R.; Gregory, Christian T.

    1997-05-06

    A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

  13. Evaluation of Variable Refrigerant Flow Systems Performance and the Enhanced Control Algorithm on Oak Ridge National Laboratory s Flexible Research Platform

    SciTech Connect (OSTI)

    Im, Piljae; Munk, Jeffrey D; Gehl, Anthony C

    2015-06-01

    A research project Evaluation of Variable Refrigerant Flow (VRF) Systems Performance and the Enhanced Control Algorithm on Oak Ridge National Laboratorys (ORNLs) Flexible Research Platform was performed to (1) install and validate the performance of Samsung VRF systems compared with the baseline rooftop unit (RTU) variable-air-volume (VAV) system and (2) evaluate the enhanced control algorithm for the VRF system on the two-story flexible research platform (FRP) in Oak Ridge, Tennessee. Based on the VRF system designed by Samsung and ORNL, the system was installed from February 18 through April 15, 2014. The final commissioning and system optimization were completed on June 2, 2014, and the initial test for system operation was started the following day, June 3, 2014. In addition, the enhanced control algorithm was implemented and updated on June 18. After a series of additional commissioning actions, the energy performance data from the RTU and the VRF system were monitored from July 7, 2014, through February 28, 2015. Data monitoring and analysis were performed for the cooling season and heating season separately, and the calibrated simulation model was developed and used to estimate the energy performance of the RTU and VRF systems. This final report includes discussion of the design and installation of the VRF system, the data monitoring and analysis plan, the cooling season and heating season data analysis, and the building energy modeling study

  14. Variable emissivity laser thermal control system

    DOE Patents [OSTI]

    Milner, Joseph R. (Livermore, CA)

    1994-01-01

    A laser thermal control system for a metal vapor laser maintains the wall mperature of the laser at a desired level by changing the effective emissivity of the water cooling jacket. This capability increases the overall efficiency of the laser.

  15. Variable emissivity laser thermal control system

    DOE Patents [OSTI]

    Milner, J.R.

    1994-10-25

    A laser thermal control system for a metal vapor laser maintains the wall temperature of the laser at a desired level by changing the effective emissivity of the water cooling jacket. This capability increases the overall efficiency of the laser. 8 figs.

  16. Efficient Thermally Variable Cooling System | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Thermally Variable Cooling System Efficient Thermally Variable Cooling System Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon p-07_fulton.pdf More Documents & Publications CX-003867: Categorical Exclusion Determination EA-1704: Final Environmental Assessment Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel Economy and Emissions Estimates

  17. Quantifying Interannual Variability for Photovoltaic Systems in PVWatts

    SciTech Connect (OSTI)

    Ryberg, David Severin; Freeman, Janine; Blair, Nate

    2015-10-01

    The National Renewable Energy Laboratory's (NREL's) PVWatts is a relatively simple tool used by industry and individuals alike to easily estimate the amount of energy a photovoltaic (PV) system will produce throughout the course of a typical year. PVWatts Version 5 has previously been shown to be able to reasonably represent an operating system's output when provided with concurrent weather data, however this type of data is not available when estimating system output during future time frames. For this purpose PVWatts uses weather data from typical meteorological year (TMY) datasets which are available on the NREL website. The TMY files represent a statistically 'typical' year which by definition excludes anomalous weather patterns and as a result may not provide sufficient quantification of project risk to the financial community. It was therefore desired to quantify the interannual variability associated with TMY files in order to improve the understanding of risk associated with these projects. To begin to understand the interannual variability of a PV project, we simulated two archetypal PV system designs, which are common in the PV industry, in PVWatts using the NSRDB's 1961-1990 historical dataset. This dataset contains measured hourly weather data and spans the thirty years from 1961-1990 for 239 locations in the United States. To note, this historical dataset was used to compose the TMY2 dataset. Using the results of these simulations we computed several statistical metrics which may be of interest to the financial community and normalized the results with respect to the TMY energy prediction at each location, so that these results could be easily translated to similar systems. This report briefly describes the simulation process used and the statistical methodology employed for this project, but otherwise focuses mainly on a sample of our results. A short discussion of these results is also provided. It is our hope that this quantification of the interannual variability of PV systems will provide a starting point for variability considerations in future PV system designs and investigations. however this type of data is not available when estimating system output during future time frames.

  18. Electromagnetic variable degrees of freedom actuator systems and methods

    DOE Patents [OSTI]

    Montesanti, Richard C. (Pleasanton, CA); Trumper, David L. (Plaistow, NH); Kirtley, Jr., James L. (Brookline, MA)

    2009-02-17

    The present invention provides a variable reluctance actuator system and method that can be adapted for simultaneous rotation and translation of a moving element by applying a normal-direction magnetic flux on the moving element. In a beneficial example arrangement, the moving element includes a swing arm that carries a cutting tool at a set radius from an axis of rotation so as to produce a rotary fast tool servo that provides a tool motion in a direction substantially parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. An actuator rotates a swing arm such that a cutting tool moves toward and away from a mounted rotating workpiece in a controlled manner in order to machine the workpiece. Position sensors provide rotation and displacement information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in feed slide of a precision lathe.

  19. Demonstration of a Variable Phase Turbine Power System for Low Temperature

    Office of Environmental Management (EM)

    Geothermal Resources | Department of Energy Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Project objectives: Demonstrate a 1 megawatt Variable Phase Turbine and Variable Phase Cycle with low temperature brine. PDF icon low_hays_variable_phase_turbine.pdf More Documents & Publications track 1: Low Temp | geothermal 2015 peer review track 3:

  20. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    SciTech Connect (OSTI)

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-03-16

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling converter provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling engine. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 deg. C while the heat losses caused by the addition of the VCHP are 1.8 W.

  1. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    SciTech Connect (OSTI)

    Hong, Tainzhen; Liu, Xaiobing

    2009-11-01

    With the current movement toward net zero energy buildings, many technologies are promoted with emphasis on their superior energy efficiency. The variable refrigerant flow (VRF) and ground source heat pump (GSHP) systems are probably the most competitive technologies among these. However, there are few studies reporting the energy efficiency of VRF systems compared with GSHP systems. In this article, a preliminary comparison of energy efficiency between the air-source VRF and GSHP systems is presented. The computer simulation results show that GSHP system is more energy efficient than the air-source VRF system for conditioning a small office building in two selected US climates. In general, GSHP system is more energy efficient than the air-source VRV system, especially when the building has significant heating loads. For buildings with less heating loads, the GSHP system could still perform better than the air-source VRF system in terms of energy efficiency, but the resulting energy savings may be marginal.

  2. Measuring Advances in HVAC Distribution System Design

    SciTech Connect (OSTI)

    Franconi, E.

    1998-05-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HV AC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  3. Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Gasoline Powertrains | Department of Energy Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Presents two-stage variable compression ratio mechanism realized by varying the connecting rod length, description of the system layout, working principle and expected fuel savings benefits when used in current and future gasoline engine concepts PDF icon

  4. System and method of modulating electrical signals using photoconductive wide bandgap semiconductors as variable resistors

    DOE Patents [OSTI]

    Harris, John Richardson; Caporaso, George J; Sampayan, Stephen E

    2013-10-22

    A system and method for producing modulated electrical signals. The system uses a variable resistor having a photoconductive wide bandgap semiconductor material construction whose conduction response to changes in amplitude of incident radiation is substantially linear throughout a non-saturation region to enable operation in non-avalanche mode. The system also includes a modulated radiation source, such as a modulated laser, for producing amplitude-modulated radiation with which to direct upon the variable resistor and modulate its conduction response. A voltage source and an output port, are both operably connected to the variable resistor so that an electrical signal may be produced at the output port by way of the variable resistor, either generated by activation of the variable resistor or propagating through the variable resistor. In this manner, the electrical signal is modulated by the variable resistor so as to have a waveform substantially similar to the amplitude-modulated radiation.

  5. Control system and method for a power delivery system having a continuously variable ratio transmission

    DOE Patents [OSTI]

    Frank, A.A.

    1984-07-10

    A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine. 4 figs.

  6. Control system and method for a power delivery system having a continuously variable ratio transmission

    DOE Patents [OSTI]

    Frank, Andrew A. (1034 Hillside Ave., Madison, WI 53705)

    1984-01-01

    A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine.

  7. Production-Intent Lost-Motion Variable Valve Actuation Systems | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Production-Intent Lost-Motion Variable Valve Actuation Systems Production-Intent Lost-Motion Variable Valve Actuation Systems Variable valve actuation with on/off IEGR pre-bump is an enabling technology for HCCI, PCCI, LTC and other advanced combustion techniques, and designs for production-intent equipment have been developed PDF icon deer09_ernest.pdf More Documents & Publications Expanding Robust HCCI Operation (Delphi CRADA) Rapid Compression Machine … A Key Experimental

  8. Method and system to estimate variables in an integrated gasification combined cycle (IGCC) plant

    DOE Patents [OSTI]

    Kumar, Aditya; Shi, Ruijie; Dokucu, Mustafa

    2013-09-17

    System and method to estimate variables in an integrated gasification combined cycle (IGCC) plant are provided. The system includes a sensor suite to measure respective plant input and output variables. An extended Kalman filter (EKF) receives sensed plant input variables and includes a dynamic model to generate a plurality of plant state estimates and a covariance matrix for the state estimates. A preemptive-constraining processor is configured to preemptively constrain the state estimates and covariance matrix to be free of constraint violations. A measurement-correction processor may be configured to correct constrained state estimates and a constrained covariance matrix based on processing of sensed plant output variables. The measurement-correction processor is coupled to update the dynamic model with corrected state estimates and a corrected covariance matrix. The updated dynamic model may be configured to estimate values for at least one plant variable not originally sensed by the sensor suite.

  9. System for throttling and compensation for variable feedstock properties

    DOE Patents [OSTI]

    Meyer, John W. (Palo Alto, CA)

    1981-01-01

    Apparatus is shown for adjusting the feed rate of pulverized feed material into a pressurized container. The apparatus also has utility for compensating for variations in the permeability of the feed material. A rotor that includes sprues with provision for controlling the pressure distribution along the sprues is located within the pressurized container. The rotor hub is connected to a drive means and a material supply means which extend through the wall of the container. A line for controlling pressure along the sprues by gas injection is connected to a chamber between sections of the sprue for controlling gas pressure at that point. The gas pressure control line is connected to a pressurized gas source and a control system external to the rotor.

  10. System for throttling and compensation for variable feedstock properties

    DOE Patents [OSTI]

    Meyer, J. W.

    1981-05-05

    Apparatus is shown for adjusting the feed rate of pulverized feed material into a pressurized container. The apparatus also has utility for compensating for variations in the permeability of the feed material. A rotor that includes sprues with provision for controlling the pressure distribution along the sprues is located within the pressurized container. The rotor hub is connected to a drive means and a material supply means which extend through the wall of the container. A line for controlling pressure along the sprues by gas injection is connected to a chamber between sections of the sprue for controlling gas pressure at that point. The gas pressure control line is connected to a pressurized gas source and a control system external to the rotor. 10 figs.

  11. Variable-Speed, Low-Cost Motor for Residential HVAC Systems | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Variable-Speed, Low-Cost Motor for Residential HVAC Systems Variable-Speed, Low-Cost Motor for Residential HVAC Systems Lower-Cost, Variable-Speed Electric Motor Improves Energy Efficiency In 2011, the U.S. industrial, commercial, and residential sectors consumed ~13.5 quad of electricity, of which an estimated 7.8 quad (58%) was consumed by applications using electric motors in machinery; process cooling; and refrigeration, space heating, ventilation, and air-conditioning. As energy

  12. The RenewElec Project: Variable Renewable Energy and the Power System

    SciTech Connect (OSTI)

    Apt, Jay

    2014-02-14

    Variable energy resources, such as wind power, now produce about 4% of U.S. electricity. They can play a significantly expanded role if the U.S. adopts a systems approach that considers affordability, security and reliability. Reaching a 20-30% renewable portfolio standard goal is possible, but not without changes in the management and regulation of the power system, including accurately assessing and preparing for the operational effects of renewable generation. The RenewElec project will help the nation make the transition to the use of significant amounts of electric generation from variable and intermittent sources of renewable power.

  13. Compatible and Cost-Effective Fault Diagnostic Solutions for...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ...Variable Air Volume and Air Handling Unit-Constant Air Volume Systems - 2014 BTO Peer Review Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable ...

  14. Variable mode bi-directional and uni-directional computer communication system

    DOE Patents [OSTI]

    Cornett, Frank N.; Jenkins, Philip N.; Bowman, Terrance L.; Placek, Joseph M.; Thorson, Gregory M.

    2004-12-14

    A variable communication systems comprising a plurality of transceivers and a control circuit connected to the transceivers to configure the transceivers to operate in a bi-directional mode and a uni-directional mode at different times using different transfer methods to transfer data.

  15. Variable-speed wind power system with improved energy capture via multilevel conversion

    DOE Patents [OSTI]

    Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

    2005-05-31

    A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

  16. Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources G015153 Principal Investigator Lance Hays Energent Corporation May 19, 2010 This presentation does not contain any proprietary confidential, or otherwise restricted information. 2 | US DOE Geothermal Program eere.energy.gov - Timeline * Project start date September 15, 2005 * Project end date September 30, 2012 * Percent complete 15% - Budget * Total project funding$4,080,257 * DOE share $2,010,075 *

  17. Variable Renewable Generation can Provide Balancing Control to the Electric Power System (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-09-01

    As wind and solar plants become more common in the electric power system, they may be called on to provide grid support services to help maintain system reliability. For example, through the use of inertial response, primary frequency response, and automatic generation control (also called secondary frequency response), wind power can provide assistance in balancing the generation and load on the system. These active power (i.e., real power) control services have the potential to assist the electric power system in times of disturbances and during normal conditions while also potentially providing economic value to consumers and variable renewable generation owners. This one-page, two-sided fact sheet discusses the grid-friendly support and benefits renewables can provide to the electric power system.

  18. Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources

    SciTech Connect (OSTI)

    Hays, Lance G

    2014-07-07

    A variable phase turbine assembly will be designed and manufactured having a turbine, operable with transcritical, two-phase or vapor flow, and a generator – on the same shaft supported by process lubricated bearings. The assembly will be hermetically sealed and the generator cooled by the refrigerant. A compact plate-fin heat exchanger or tube and shell heat exchanger will be used to transfer heat from the geothermal fluid to the refrigerant. The demonstration turbine will be operated separately with two-phase flow and with vapor flow to demonstrate performance and applicability to the entire range of low temperature geothermal resources. The vapor leaving the turbine is condensed in a plate-fin refrigerant condenser. The heat exchanger, variable phase turbine assembly and condenser are all mounted on single skids to enable factory assembly and checkout and minimize installation costs. The system will be demonstrated using low temperature (237F) well flow from an existing large geothermal field. The net power generated, 1 megawatt, will be fed into the existing power system at the demonstration site. The system will demonstrate reliable generation of inexpensive power from low temperature resources. The system will be designed for mass manufacturing and factory assembly and should cost less than $1,200/kWe installed, when manufactured in large quantities. The estimated cost of power for 300F resources is predicted to be less than 5 cents/kWh. This should enable a substantial increase in power generated from low temperature geothermal resources.

  19. Non-invasive energy meter for fixed and variable flow systems

    DOE Patents [OSTI]

    Menicucci, David F.; Black, Billy D.

    2005-11-01

    An energy metering method and apparatus for liquid flow systems comprising first and second segments of one or more conduits through which a liquid flows, comprising: attaching a first temperature sensor for connection to an outside of the first conduit segment; attaching a second temperature sensor for connection to an outside of the second conduit segment; via a programmable control unit, receiving data from the sensors and calculating energy data therefrom; and communicating energy data from the meter; whereby the method and apparatus operate without need to temporarily disconnect or alter the first or second conduit segments. The invention operates with both variable and fixed flow systems, and is especially useful for both active and passive solar energy systems.

  20. A nuclear wind/solar oil-shale system for variable electricity and liquid fuels production

    SciTech Connect (OSTI)

    Forsberg, C.

    2012-07-01

    The recoverable reserves of oil shale in the United States exceed the total quantity of oil produced to date worldwide. Oil shale contains no oil, rather it contains kerogen which when heated decomposes into oil, gases, and a carbon char. The energy required to heat the kerogen-containing rock to produce the oil is about a quarter of the energy value of the recovered products. If fossil fuels are burned to supply this energy, the greenhouse gas releases are large relative to producing gasoline and diesel from crude oil. The oil shale can be heated underground with steam from nuclear reactors leaving the carbon char underground - a form of carbon sequestration. Because the thermal conductivity of the oil shale is low, the heating process takes months to years. This process characteristic in a system where the reactor dominates the capital costs creates the option to operate the nuclear reactor at base load while providing variable electricity to meet peak electricity demand and heat for the shale oil at times of low electricity demand. This, in turn, may enable the large scale use of renewables such as wind and solar for electricity production because the base-load nuclear plants can provide lower-cost variable backup electricity. Nuclear shale oil may reduce the greenhouse gas releases from using gasoline and diesel in half relative to gasoline and diesel produced from conventional oil. The variable electricity replaces electricity that would have been produced by fossil plants. The carbon credits from replacing fossil fuels for variable electricity production, if assigned to shale oil production, results in a carbon footprint from burning gasoline or diesel from shale oil that may half that of conventional crude oil. The U.S. imports about 10 million barrels of oil per day at a cost of a billion dollars per day. It would require about 200 GW of high-temperature nuclear heat to recover this quantity of shale oil - about two-thirds the thermal output of existing nuclear reactors in the United States. With the added variable electricity production to enable renewables, additional nuclear capacity would be required. (authors)

  1. Variable C : N : P stoichiometry of dissolved organic matter cycling in the Community Earth System Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Letscher, R. T.; Moore, J. K.; Teng, Y. -C.; Primeau, F.

    2015-01-12

    Dissolved organic matter (DOM) plays an important role in the ocean's biological carbon pump by providing an advective/mixing pathway for ~ 20% of export production. DOM is known to have a stoichiometry depleted in nitrogen (N) and phosphorus (P) compared to the particulate organic matter pool, a fact that is often omitted from biogeochemical ocean general circulation models. However the variable C : N : P stoichiometry of DOM becomes important when quantifying carbon export from the upper ocean and linking the nutrient cycles of N and P with that of carbon. Here we utilize recent advances in DOM observationalmore » data coverage and offline tracer-modeling techniques to objectively constrain the variable production and remineralization rates of the DOM C : N : P pools in a simple biogeochemical-ocean model of DOM cycling. The optimized DOM cycling parameters are then incorporated within the Biogeochemical Elemental Cycling (BEC) component of the Community Earth System Model (CESM) and validated against the compilation of marine DOM observations. The optimized BEC simulation including variable DOM C : N : P cycling was found to better reproduce the observed DOM spatial gradients than simulations that used the canonical Redfield ratio. Global annual average export of dissolved organic C, N, and P below 100 m was found to be 2.28 Pg C yr-1 (143 Tmol C yr-1, 16.4 Tmol N yr-1, and 1 Tmol P yr-1, respectively, with an average export C : N : P stoichiometry of 225 : 19 : 1 for the semilabile (degradable) DOM pool. Dissolved organic carbon (DOC) export contributed ~ 25% of the combined organic C export to depths greater than 100 m.« less

  2. Variable C : N : P stoichiometry of dissolved organic matter cycling in the Community Earth System Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Letscher, R. T.; Moore, J. K.; Teng, Y. -C.; Primeau, F.

    2014-06-16

    Dissolved organic matter (DOM) plays an important role in the ocean's biological carbon pump by providing an advective/mixing pathway for ~ 20% of export production. DOM is known to have a stoichiometry depleted in nitrogen (N) and phosphorus (P) compared to the particulate organic matter pool, a~fact that is often omitted from biogeochemical-ocean general circulation models. However the variable C : N : P stoichiometry of DOM becomes important when quantifying carbon export from the upper ocean and linking the nutrient cycles of N and P with that of carbon. Here we utilize recent advances in DOM observational data coveragemore » and offline tracer-modeling techniques to objectively constrain the variable production and remineralization rates of the DOM C / N / P pools in a simple biogeochemical-ocean model of DOM cycling. The optimized DOM cycling parameters are then incorporated within the Biogeochemical Elemental Cycling (BEC) component of the Community Earth System Model and validated against the compilation of marine DOM observations. The optimized BEC simulation including variable DOM C : N : P cycling was found to better reproduce the observed DOM spatial gradients than simulations that used the canonical Redfield ratio. Global annual average export of dissolved organic C, N, and P below 100 m was found to be 2.28 Pg C yr-1 (143 Tmol C yr-1), 16.4 Tmol N yr-1, and 1 Tmol P yr-1, respectively with an average export C : N : P stoichiometry of 225 : 19 : 1 for the semilabile (degradable) DOM pool. DOC export contributed ~ 25% of the combined organic C export to depths greater than 100 m.« less

  3. Probabilistic Approach to Quantifying the Contribution of Variable Generation and Transmission to System Reliability: Preprint

    SciTech Connect (OSTI)

    Ibanez, E.; Milligan, M.

    2012-09-01

    The increasing electrical load served by variable generation (VG), such as wind and solar energy, in the United States and many other countries has stimulated an interesting line of research to better quantify the capacity value of these resources. Methods applied traditionally to thermal units based on their average outage rates do not apply to VG because of their uncertain and non-dispatchable nature. The North American Electric Reliability Corporation's Integration of Variable Generation Task Force recently released a report that highlighted the need to develop and benchmark underlying loss-of-load expectation and related metrics that reasonably and fairly calculate the contribution to planning reserves, or capacity value, of solar and wind power. As the fraction of generation coming from VG becomes more significant, their estimated capacity value will have a larger impact on system planning. In this paper, we provide a method to include VG in traditional probabilistic-based adequacy methods. This method has been implemented in the Renewable Energy Probabilistic Resource Assessment tool developed at the National Renewable Energy Laboratory. Through an example based on the U.S. Western Interconnection, this method is applied to assess the effect that transmission can have on resource adequacy. We also analyze the interactions between available transmission and capacity value for VG.

  4. A Generalized Stability Analysis of the AMOC in Earth System Models: Implication for Decadal Variability and Abrupt Climate Change

    SciTech Connect (OSTI)

    Fedorov, Alexey V.; Fedorov, Alexey

    2015-01-14

    The central goal of this research project was to understand the mechanisms of decadal and multi-decadal variability of the Atlantic Meridional Overturning Circulation (AMOC) as related to climate variability and abrupt climate change within a hierarchy of climate models ranging from realistic ocean models to comprehensive Earth system models. Generalized Stability Analysis, a method that quantifies the transient and asymptotic growth of perturbations in the system, is one of the main approaches used throughout this project. The topics we have explored range from physical mechanisms that control AMOC variability to the factors that determine AMOC predictability in the Earth system models, to the stability and variability of the AMOC in past climates.

  5. Future projection of mean and variability of the Asian Summer Monsoon and Indian Ocean Climate systems

    SciTech Connect (OSTI)

    Annamalai, H

    2014-09-15

    The overall goal of this project is to assess the ability of the CMIP3/5 models to simulate the Indian-Ocean monsoon systems. The PI along with post-docs investigated research issues ranging from synoptic systems to long-term trends over the Asian monsoon region. The PI applied diagnostic tools such as moist static energy (MSE) to isolate: the moist and radiative processes responsible for extended monsoon breaks over South Asia, precursors in the ENSO-monsoon association, reasons for the drying tendency over South Asia and the possible effect on tropical Indian Ocean climate anomalies influencing certain aspects of ENSO characteristics. By diagnosing various observations and coupled model simulations, we developed working hypothesis and tested them by carrying out sensitivity experiments with both linear and nonlinear models. Possible physical and dynamical reasons for model sensitivities were deduced. On the teleconnection front, the ability of CMIP5 models in representing the monsoon-desert mechanism was examined recently. Further more, we have applied a suite of diagnostics and have performed an in depth analysis on CMIP5 integrations to isolate the possible reasons for the ENSO-monsoon linkage or lack thereof. The PI has collaborated with Dr. K.R. Sperber of PCMDI and other CLIVAR Asian-Australian monsoon panel members in understanding the ability of CMIP3/5 models in capturing monsoon and its spectrum of variability. The objective and process-based diagnostics aided in selecting models that best represent the present-day monsoon and its variability that are then employed for future projections. Two major highlights were an invitation to write a review on present understanding monsoons in a changing climate in Nature Climate Change, and identification of an east-west shift in observed monsoon rainfall (more rainfall over tropical western Pacific and drying tendency over South Asia) in the last six decades and attributing that shift to SST rise over the tropical western Pacific. On the training of post-doctoral scientists: the PI spent considerable amount of time and efforts in introducing the post-docs into climate modeling and designing the numerical experiments. With training provided and knowledge gained, post-docs worked in the project obtained long term positions elsewhere. The PI also enjoyed the experience in managing the works and educating work ethics to the younger generation. Based on the research achievements and publications, the PI gave invited talks in major international monsoon conferences/workshops, and gave lectures in various research organizations in the last six years. Finally, during the project period, the PI attended all the DOE organized PIs meeting and presented the major results. Some of the major implications of the project include: (i) Sustained observational efforts are necessary to monitor the three-dimensional moisture distribution over the Asian monsoon region that would aid in better understanding, modeling and predicting severe monsoons well in advance and (ii) process-based diagnostics lead pathways for model improvements.

  6. LANAI HIGH-DENSITY IRRADIANCE SENSOR NETWORK FOR CHARACTERIZING SOLAR RESOURCE VARIABILITY OF MW-SCALE PV SYSTEM

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    LANAI HIGH-DENSITY IRRADIANCE SENSOR NETWORK FOR CHARACTERIZING SOLAR RESOURCE VARIABILITY OF MW-SCALE PV SYSTEM Scott Kuszamaul 1 , Abraham Ellis 1 , Joshua Stein 1 , and Lars Johnson 2 1 Sandia National Laboratories, Albuquerque, NM, USA 2 SunPower Corporation, Richmond, CA, USA ABSTRACT Sandia National Laboratories (Sandia) and SunPower Corporation (SunPower) have completed design and deployment of an autonomous irradiance monitoring system based on wireless mesh communications and a battery

  7. Ota City : characterizing output variability from 553 homes with residential PV systems on a distribution feeder.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Miyamoto, Yusuke; Nakashima, Eichi; Lave, Matthew

    2011-11-01

    This report describes in-depth analysis of photovoltaic (PV) output variability in a high-penetration residential PV installation in the Pal Town neighborhood of Ota City, Japan. Pal Town is a unique test bed of high-penetration PV deployment. A total of 553 homes (approximately 80% of the neighborhood) have grid-connected PV totaling over 2 MW, and all are on a common distribution line. Power output at each house and irradiance at several locations were measured once per second in 2006 and 2007. Analysis of the Ota City data allowed for detailed characterization of distributed PV output variability and a better understanding of how variability scales spatially and temporally. For a highly variable test day, extreme power ramp rates (defined as the 99th percentile) were found to initially decrease with an increase in the number of houses at all timescales, but the reduction became negligible after a certain number of houses. Wavelet analysis resolved the variability reduction due to geographic diversity at various timescales, and the effect of geographic smoothing was found to be much more significant at shorter timescales.

  8. Recent Developments of the Modelica"Buildings" Library for Building Energy and Control Systems

    SciTech Connect (OSTI)

    Wetter, Michael; Zuo, Wangda; Nouidui, Thierry Stephane

    2011-04-01

    At the Modelica 2009 conference, we introduced the Buildings library, a freely available Modelica library for building energy and control systems. This paper reports the updates of the library and presents example applications for a range of heating, ventilation and air conditioning (HVAC) systems. Over the past two years, the library has been further developed. The number of HVAC components models has been doubled and various components have been revised to increase numerical robustness.The paper starts with an overview of the library architecture and a description of the main packages. To demonstrate the features of the Buildings library, applications that include multizone airflow simulation as well as supervisory and local loop control of a variable air volume (VAV) system are briefly described. The paper closes with a discussion of the current development.

  9. Variable current-voltage TPV device for use in a thermophotovoltaic energy conversion system

    DOE Patents [OSTI]

    Charache, Greg W. (Clifton Park, NY); Baldasaro, Paul F. (Clifton Park, NY); Campbell, Brian C. (Scotia, NY)

    2000-01-01

    A front-side or back-side illuminated variable current-voltage thermophotovoltaic device comprises a support substrate; isolation layers disposed on the support substrate; a plurality of cells disposed on the isolation layers, each of the cells including a base layer and an emitter layer; an insulating member disposed between each of the cells configured to isolate each cell from adjacent cells; an ohmic contact configured to connect each cell to another cell in series; and a spectral control device disposed on top of the cells and/or on the bottom surface of the support substrate.

  10. Coexistence of unlimited bipartite and genuine multipartite entanglement: Promiscuous quantum correlations arising from discrete to continuous-variable systems

    SciTech Connect (OSTI)

    Adesso, Gerardo; Ericsson, Marie; Illuminati, Fabrizio

    2007-08-15

    Quantum mechanics imposes 'monogamy' constraints on the sharing of entanglement. We show that, despite these limitations, entanglement can be fully 'promiscuous', i.e., simultaneously present in unlimited two-body and many-body forms in states living in an infinite-dimensional Hilbert space. Monogamy just bounds the divergence rate of the various entanglement contributions. This is demonstrated in simple families of N-mode (N{>=}4) Gaussian states of light fields or atomic ensembles, which therefore enable infinitely more freedom in the distribution of information, as opposed to systems of individual qubits. Such a finding is of importance for the quantification, understanding, and potential exploitation of shared quantum correlations in continuous variable systems. We discuss how promiscuity gradually arises when considering simple families of discrete variable states, with increasing Hilbert space dimension towards the continuous variable limit. Such models are somehow analogous to Gaussian states with asymptotically diverging, but finite, squeezing. In this respect, we find that non-Gaussian states (which in general are more entangled than Gaussian states) exhibit also the interesting feature that their entanglement is more shareable: in the non-Gaussian multipartite arena, unlimited promiscuity can be already achieved among three entangled parties, while this is impossible for Gaussian, even infinitely squeezed states.

  11. Modeling of heat extraction from variably fractured porous media in Enhanced Geothermal Systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hadgu, Teklu; Kalinina, Elena Arkadievna; Lowry, Thomas Stephen

    2016-01-30

    Modeling of heat extraction in Enhanced Geothermal Systems is presented. The study builds on recent studies on the use of directional wells to improve heat transfer between doublet injection and production wells. The current study focuses on the influence of fracture orientation on production temperature in deep low permeability geothermal systems, and the effects of directional drilling and separation distance between boreholes on heat extraction. The modeling results indicate that fracture orientation with respect to the well-pair plane has significant influence on reservoir thermal drawdown. As a result, the vertical well doublet is impacted significantly more than the horizontal wellmore » doublet« less

  12. Calculating Individual Resources Variability and Uncertainty Factors Based on Their Contributions to the Overall System Balancing Needs

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Pai, M. A.; McManus, Bart

    2014-01-14

    The variability and uncertainty of wind power production requires increased flexibility in power systems, or more operational reserves to main a satisfactory level of reliability. The incremental increase in reserve requirement caused by wind power is often studied separately from the effects of loads. Accordingly, the cost in procuring reserves is allocated based on this simplification rather than a fair and transparent calculation of the different resources contribution to the reserve requirement. This work proposes a new allocation mechanism for intermittency and variability of resources regardless of their type. It is based on a new formula, called grid balancing metric (GBM). The proposed GBM has several distinct features: 1) it is directly linked to the control performance standard (CPS) scores and interconnection frequency performance, 2) it provides scientifically defined allocation factors for individual resources, 3) the sum of allocation factors within any group of resources is equal to the groups collective allocation factor (linearity), and 4) it distinguishes helpers and harmers. The paper illustrates and provides results of the new approach based on actual transmission system operator (TSO) data.

  13. Sub-Hour Solar Data for Power System Modeling From Static Spatial Variability Analysis: Preprint

    SciTech Connect (OSTI)

    Hummon, M.; Ibanez, E.; Brinkman, G.; Lew, D.

    2012-12-01

    High penetration renewable integration studies need high quality solar power data with spatial-temporal correlations that are representative of a real system. This paper will summarize the research relating sequential point-source sub-hour global horizontal irradiance (GHI) values to static, spatially distributed GHI values. This research led to the development of an algorithm for generating coherent sub-hour datasets that span distances ranging from 10 km to 4,000 km. The algorithm, in brief, generates synthetic GHI values at an interval of one-minute, for a specific location, using SUNY/Clean Power Research, satellite-derived, hourly irradiance values for the nearest grid cell to that location and grid cells within 40 km.

  14. Variable accretion processes in the young binary-star system UY Aur

    SciTech Connect (OSTI)

    Stone, Jordan M.; Eisner, J. A.; Kulesa, Craig; McCarthy, Don; Salyk, Colette E-mail: jeisner@as.arizona.edu E-mail: dmccarthy@as.arizona.edu

    2014-09-01

    We present new K-band spectroscopy of the UY Aur binary star system. Our data are the first to show H{sub 2} emission in the spectrum of UY Aur A and the first to spectrally resolve the Br? line in the spectrum of UY Aur B. We see an increase in the strength of the Br? line in UY Aur A and a decrease in Br? and H{sub 2} line luminosity for UY Aur B compared to previous studies. Converting Br? line luminosity to accretion rate, we infer that the accretion rate onto UY Aur A has increased by 2 10{sup 9} M {sub ?} yr{sup 1} per year since a rate of zero was observed in 1994. The Br? line strength for UY Aur B has decreased by a factor of 0.54 since 1994, but the K-band flux has increased by 0.9 mag since 1998. The veiling of UY Aur B has also increased significantly. These data evince a much more luminous disk around UY Aur B. If the lower Br? luminosity observed in the spectrum of UY Aur B indicates an intrinsically smaller accretion rate onto the star, then UY Aur A now accretes at a higher rate than UY Aur B. However, extinction at small radii or mass pile-up in the circumstellar disk could explain decreased Br? emission around UY Aur B even when the disk luminosity implies an increased accretion rate. In addition to our scientific results for the UY Aur system, we discuss a dedicated pipeline we have developed for the reduction of echelle-mode data from the ARIES spectrograph.

  15. Variable oxygen/nitrogen enriched intake air system for internal combustion engine applications

    DOE Patents [OSTI]

    Poola, Ramesh B. (Woodridge, IL); Sekar, Ramanujam R. (Naperville, IL); Cole, Roger L. (Elmhurst, IL)

    1997-01-01

    An air supply control system for selectively supplying ambient air, oxygen enriched air and nitrogen enriched air to an intake of an internal combustion engine includes an air mixing chamber that is in fluid communication with the air intake. At least a portion of the ambient air flowing to the mixing chamber is selectively diverted through a secondary path that includes a selectively permeable air separating membrane device due a differential pressure established across the air separating membrane. The permeable membrane device separates a portion of the nitrogen in the ambient air so that oxygen enriched air (permeate) and nitrogen enriched air (retentate) are produced. The oxygen enriched air and the nitrogen enriched air can be selectively supplied to the mixing chamber or expelled to atmosphere. Alternatively, a portion of the nitrogen enriched air can be supplied through another control valve to a monatomic-nitrogen plasma generator device so that atomic nitrogen produced from the nitrogen enriched air can be then injected into the exhaust of the engine. The oxygen enriched air or the nitrogen enriched air becomes mixed with the ambient air in the mixing chamber and then the mixed air is supplied to the intake of the engine. As a result, the air being supplied to the intake of the engine can be regulated with respect to the concentration of oxygen and/or nitrogen.

  16. Investigation of a rotary valving system with variable valve timing for internal combustion engines: Final technical report

    SciTech Connect (OSTI)

    Cross, P.C.; Hansen, C.N.

    1994-11-18

    The objective of the program was to provide a functional demonstration of the Hansen Rotary Valving System with Variable Valve timing (HRVS/VVT), capable of throttleless inlet charge control, as an alternative to conventional poppet-valves for use in spark ignited internal combustion engines. The goal of this new technology is to secure benefits in fuel economy, broadened torque band, vibration reduction, and overhaul accessibility. Additionally, use of the variable valve timing capability to vary the effective compression ratio is expected to improve multi-fuel tolerance and efficiency. Efforts directed at the design of HRVS components proved to be far more extensive than had been anticipated, ultimately requiring that proof-trial design/development work be performed. Although both time and funds were exhausted before optical or ion-probe types of in-cylinder investigation could be undertaken, a great deal of laboratory data was acquired during the course of the design/development work. This laboratory data is the basis for the information presented in this Final Report.

  17. Variable Refrigerant Flow Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Utility Resources News & Events Expand News & Events Skip navigation links Smart Grid Demand Response Energy Efficiency Emerging Technologies Current Research Portfolio...

  18. SU-E-T-453: A Novel Daily QA System for Robotic Image Guided Radiosurgery with Variable Aperture Collimator

    SciTech Connect (OSTI)

    Wang, L; Nelson, B

    2014-06-01

    Purpose: A novel end-to-end system using a CCD camera and a scintillator based phantom that is capable of measuring the beam-by-beam delivery accuracy of Robotic Radiosurgery has been developed and reported in our previous work. This work investigates its application to end-to-end type daily QA for Robotic Radiosurgery (Cyberknife) with Variable Aperture Collimator (Iris). Methods: The phantom was first scanned with a CT scanner at 0.625 slice thickness and exported to the Cyberknife Muliplan (v4.6) treatment planning system. An isocentric treatment plan was created consisting of ten beams of 25 Monitor Units each using Iris apertures of 7.5, 10, 15, 20, and 25 mm. The plan was delivered six times in two days on the Cyberknife G4 system with fiducial tracking on the four metal fiducials embedded in phantom with re-positioning between the measurements. The beam vectors (X, Y, Z) are measured and compared with the plan from the machine delivery file (XML file). The Iris apertures (FWHM) were measured from the beam flux map and compared with the commissioning data. Results: The average beam positioning accuracies of the six deliveries are 0.71 0.40 mm, 0.72 0.44 mm, 0.74 0.42 mm, 0.70 0.40 mm, 0.79 0.44 mm and 0.69 0.41 mm respectively. Radiation beam width (FWHM) variations are within 0.05 mm, and they agree with the commissioning data within 0.22 mm. The delivery time for the plan is about 7 minutes and the results are given instantly. Conclusion: The experimental results agree with stated sub-millimeter delivery accuracy of Cyberknife system. Beam FWHM variations comply with the 0.2 mm accuracy of the Iris collimator at SAD. The XRV-100 system has proven to be a powerful tool in performing end-to-end type tests for Robotic Image Guided Radiosurgery Daily QA.

  19. Development of high-voltage pulse-slicer unit with variable pulse duration for pulse radiolysis system

    SciTech Connect (OSTI)

    Upadhyay, J.; Sharma, M. L.; Navathe, C. P.; Toley, M. A.; Shinde, S. J.; Nadkarni, S. A.; Sarkar, S. K.

    2012-02-15

    A high-voltage pulse-slicer unit with variable pulse duration has been developed and integrated with a 7 MeV linear electron accelerator (LINAC) for pulse radiolysis investigation. The pulse-slicer unit provides switching voltage from 1 kV to 10 kV with rise time better than 5 ns. Two MOSFET based 10 kV switches were configured in differential mode to get variable duration pulses. The high-voltage pulse has been applied to the deflecting plates of the LINAC for slicing of electron beam of 2 {mu}s duration. The duration of the electron beam has been varied from 30 ns to 2 {mu}s with the optimized pulse amplitude of 7 kV to get corresponding radiation doses from 6 Gy to 167 Gy.

  20. Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements: Industrial Technologies Program (ITP) Pumping Systems Tip Sheet #12

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    pumping applications with variable fow rate requirements, adjustable speed drives (ASDs) are an effcient control alternative to throttling or bypass methods. ASDs save energy by varying the pump's rotational speed. In centrifugal pumping applications with no static lift, power requirements vary, as the cube of the pump speed and small decreases in speed or fow rate can signifcantly reduce energy use. For example, reducing the speed (fow rate) by 20% can lower input power requirements by

  1. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  2. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  3. Dynamic Analysis of Hybrid Energy Systems under Flexible Operation and Variable Renewable Generation -- Part I: Dynamic Performance Analysis and Part II: Dynamic Cost

    SciTech Connect (OSTI)

    Humberto E. Garcia; Amit Mohanty; Wen-Chiao Lin; Robert S. Cherry

    2013-04-01

    Dynamic analysis of hybrid energy systems (HES) under flexible operation and variable renewable generation is considered in order to better understand various challenges and opportunities associated with the high system variability arising from the integration of renewable energy into the power grid. Unique consequences are addressed by devising advanced HES solutions in which multiple forms of energy commodities, such as electricity and chemical products, may be exchanged. Dynamic models of various unit operations are developed and integrated within two different HES options. One HES option, termed traditional, produces electricity only and consists of a primary heat generator (PHG) (e.g., a small modular reactor), a steam turbine generator, a wind farm, and a battery storage. The other HES option, termed advanced, includes not only the components present in the traditional option but also a chemical plant complex to repurpose excess energy for non-electricity services, such as for the production of chemical goods (e.g., transportation fuel). In either case, a given HES is connected to the power grid at a point of common coupling and requested to deliver a certain electricity generation profile as dictated by a regional power grid operator based on a predicted demand curve. Dynamic analysis of these highly-coupled HES are performed to identify their key dynamical properties and limitations and to prescribe solutions for best managing and mitigating the high variability introduced from incorporating renewable energy into the energy mix. A comparative dynamic cost analysis is also conducted to determine best HES options. The cost function includes a set of metrics for computing fixed costs, such as fixed operations and maintenance (O&M) and overnight capital costs, and also variable operational costs, such as cost of variability, variable O&M cost, and cost of environmental impact, together with revenues. Assuming different options for implementing PHG (e.g., natural gas, coal, nuclear), preliminary results identify the level of renewable penetration at which a given advanced HES option (e.g., a nuclear hybrid) becomes increasingly more economical than a traditional electricity-only generation solution. Conditions are also revealed under which carbon resources may be better utilized as carbon sources for chemical production rather than as combustion material for electricity generation.

  4. Application Performance Variability on Hopper

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Application Performance Variability on Hopper Application Performance Variability on Hopper Introduction The Hopper system is a Cray XE6 system with roughly 6300 compute nodes. In normal day to day operations, Hopper can be running hundreds of individual applications at any given time. Some users have reported application runtime variability, in some cases as large as 30-40%. Non-uniform runtimes makes it more difficult for scientists to measure the performance of their codes and to estimate the

  5. A computer simulation appraisal of non-residential low energy cooling systems in California

    SciTech Connect (OSTI)

    Bourassa, Norman; Haves, Philip; Huang, Joe

    2002-05-17

    An appraisal of the potential performance of different Low Energy Cooling (LEC) systems in nonresidential buildings in California is being conducted using computer simulation. The paper presents results from the first phase of the study, which addressed the systems that can be modeled, with the DOE-2.1E simulation program. The following LEC technologies were simulated as variants of a conventional variable-air-volume system with vapor compression cooling and mixing ventilation in the occupied spaces: Air-side indirect and indirect/direct evaporative pre-cooling. Cool beams. Displacement ventilation. Results are presented for four populous climates, represented by Oakland, Sacramento, Pasadena and San Diego. The greatest energy savings are obtained from a combination of displacement ventilation and air-side indirect/direct evaporative pre-cooling. Cool beam systems have the lowest peak demand but do not reduce energy consumption significantly because the reduction in fan energy is offse t by a reduction in air-side free cooling. Overall, the results indicate significant opportunities for LEC technologies to reduce energy consumption and demand in nonresidential new construction and retrofit.

  6. Lanai high-density irradiance sensor network for characterizing solar resource variability of MW-scale PV system.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Johnson, Lars; Ellis, Abraham; Kuszmaul, Scott S.

    2012-01-01

    Sandia National Laboratories (Sandia) and SunPower Corporation (SunPower) have completed design and deployment of an autonomous irradiance monitoring system based on wireless mesh communications and a battery operated data acquisition system. The Lanai High-Density Irradiance Sensor Network is comprised of 24 LI-COR{reg_sign} irradiance sensors (silicon pyranometers) polled by 19 RF Radios. The system was implemented with commercially available hardware and custom developed LabVIEW applications. The network of solar irradiance sensors was installed in January 2010 around the periphery and within the 1.2 MW ac La Ola PV plant on the island of Lanai, Hawaii. Data acquired at 1 second intervals is transmitted over wireless links to be time-stamped and recorded on SunPower data servers at the site for later analysis. The intent is to study power and solar resource data sets to correlate the movement of cloud shadows across the PV array and its effect on power output of the PV plant. The irradiance data sets recorded will be used to study the shape, size and velocity of cloud shadows. This data, along with time-correlated PV array output data, will support the development and validation of a PV performance model that can predict the short-term output characteristics (ramp rates) of PV systems of different sizes and designs. This analysis could also be used by the La Ola system operator to predict power ramp events and support the function of the future battery system. This experience could be used to validate short-term output forecasting methodologies.

  7. System and method for cancelling the effects of stray magnetic fields from the output of a variable reluctance sensor

    DOE Patents [OSTI]

    Chen, Chingchi (Ann Arbor, MI); Degner, Michael W. (Farmington Hills, MI)

    2002-11-19

    A sensor system for sensing a rotation of a sensing wheel is disclosed. The sensor system has a sensing coil in juxtaposition with the sensing wheel. Moreover, the sensing coil has a sensing coil output signal indicative of the rotational speed of the sensing wheel. Further, a cancellation coil is located remotely from the sensing coil and connected in series therewith. Additionally, the cancellation coil has a cancellation coil output signal indicative of an environmental disturbance which is effecting the sensing coil output signal. The cancellation coil output signal operates to cancel the effects of the environmental disturbance on the sensing coil output signal.

  8. The importance of input variables to a neural network fault-diagnostic system for nuclear power plants

    SciTech Connect (OSTI)

    Lanc, T.L.

    1992-01-01

    This thesis explores safety enhancement for nuclear power plants. Emergency response systems currently in use depend mainly on automatic systems engaging when certain parameters go beyond a pre-specified safety limit. Often times the operator has little or no opportunity to react since a fast scram signal shuts down the reactor smoothly and efficiently. These accidents are of interest to technical support personnel since examining the conditions that gave rise to these situations help determine causality. In many other cases an automated fault-diagnostic advisor would be a valuable tool in assisting the technicians and operators to determine what just happened and why.

  9. The importance of input variables to a neural network fault-diagnostic system for nuclear power plants

    SciTech Connect (OSTI)

    Lanc, T.L.

    1992-12-31

    This thesis explores safety enhancement for nuclear power plants. Emergency response systems currently in use depend mainly on automatic systems engaging when certain parameters go beyond a pre-specified safety limit. Often times the operator has little or no opportunity to react since a fast scram signal shuts down the reactor smoothly and efficiently. These accidents are of interest to technical support personnel since examining the conditions that gave rise to these situations help determine causality. In many other cases an automated fault-diagnostic advisor would be a valuable tool in assisting the technicians and operators to determine what just happened and why.

  10. Variable thrust cartridge

    DOE Patents [OSTI]

    Taleyarkhan, Rusi P. (Knoxville, TN)

    2000-11-07

    The present invention is a variable thrust cartridge comprising a water-molten aluminum reaction chamber from which a slug is propelled. The cartridge comprises a firing system that initiates a controlled explosion from the reaction chamber. The explosive force provides a thrust to a slug, preferably contained within the cartridge.

  11. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations

    SciTech Connect (OSTI)

    Jones, Lawrence E.

    2012-01-05

    A variety of studies have recently evaluated the opportunities for the large-scale integration of wind energy into the US power system. These studies have included, but are not limited to, "20 Percent Wind Energy by 2030: Increasing Wind Energy's Contribution to US Electricity Supply", the "Western Wind and Solar Integration Study", and the "Eastern Wind Integration and Transmission Study." Each of these US based studies have evaluated a variety of activities that can be undertaken by utilities to help integrate wind energy.

  12. Final Project Report: Self-Correcting Controls for VAV System Faults Filter/Fan/Coil and VAV Box Sections

    SciTech Connect (OSTI)

    Brambley, Michael R.; Fernandez, Nicholas; Wang, Weimin; Cort, Katherine A.; Cho, Heejin; Ngo, Hung; Goddard, James K.

    2011-05-01

    This report addresses original research by the Pacific Northwest National Laboratory for the California Institute for Energy and Environment on self-correcting controls for variable-air-volume (VAV) heating, ventilating and air-conditioning systems and focuses specifically on air handling and VAV box components of the air side of the system. A complete set of faults for these components was compiled and a fault mode analysis performed to understand the detectable symptoms of the faults and the chain of causation. A set of 26 algorithms was developed to facilitate the automatic correction of these faults in typical commercial VAV systems. These algorithms include training tests that are used during commissioning to develop models of normal system operation, passive diagnostics used to detect the symptoms of faults, proactive diagnostics used to diagnose the cause of a fault, and finally fault correction algorithms. Ten of the twenty six algorithms were implemented in a prototype software package that interfaces with a test bed facility at PNNL's Richland, WA, laboratory. Measurement bias faults were instigated in the supply-air temperature sensor and the supply-air flow meter to test the algorithms developed. The algorithms as implemented in the laboratory software correctly detected, diagnosed and corrected these faults. Finally, an economic and impact assessment was performed for the State of California for deployment of self-correcting controls. Assuming 15% HVAC energy savings and a modeled deployment profile, 3.1-5.8 TBu of energy savings are possible by year 15.

  13. Variable Definitions

    Gasoline and Diesel Fuel Update (EIA)

    CSV File Documentation Energy Source Tables This document explains the contents of the comma-separated value (CSV) files by energy source located on the State Energy Data System (SEDS) Update web page at http://www.eia.gov/state/seds/seds-data-fuel.cfm. There is a CSV file for the most recent year's data for each energy source as shown in the HTML and PDF data tables. In some cases there is one data file for two tables. The first record in each file contains the column headings. The first data

  14. Coupled ocean-atmosphere model system for studies of interannual-to-decadal climate variability over the North Pacific Basin and precipitation over the Southwestern United States

    SciTech Connect (OSTI)

    Lai, Chung-Chieng A.

    1997-10-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The ultimate objective of this research project is to make understanding and predicting regional climate easier. The long-term goals of this project are (1) to construct a coupled ocean-atmosphere model (COAM) system, (2) use it to explore the interannual-to-decadal climate variability over the North Pacific Basin, and (3) determine climate effects on the precipitation over the Southwestern United States. During this project life, three major tasks were completed: (1) Mesoscale ocean and atmospheric model; (2) global-coupled ocean and atmospheric modeling: completed the coupling of LANL POP global ocean model with NCAR CCM2+ global atmospheric model; and (3) global nested-grid ocean modeling: designed the boundary interface for the nested-grid ocean models.

  15. Strategy Guideline. Compact Air Distribution Systems

    SciTech Connect (OSTI)

    Burdick, Arlan

    2013-06-01

    This guideline discusses the benefits and challenges of using a compact air distribution system to handle the reduced loads and reduced air volume needed to condition the space within an energy efficient home. The decision criteria for a compact air distribution system must be determined early in the whole-house design process, considering both supply and return air design. However, careful installation of a compact air distribution system can result in lower material costs from smaller equipment, shorter duct runs, and fewer outlets; increased installation efficiencies, including ease of fitting the system into conditioned space; lower loads on a better balanced HVAC system, and overall improved energy efficiency of the home.

  16. Operating Reserves and Variable Generation

    SciTech Connect (OSTI)

    Ela, E.; Milligan, M.; Kirby, B.

    2011-08-01

    This report tries to first generalize the requirements of the power system as it relates to the needs of operating reserves. It also includes a survey of operating reserves and how they are managed internationally in system operations today and then how new studies and research are proposing they may be managed in the future with higher penetrations of variable generation.

  17. Comparison of heating and cooling energy consumption by HVAC system with mixing and displacement air distribution for a restaurant dining area in different climates

    SciTech Connect (OSTI)

    Zhivov, A.M.; Rymkevich, A.A.

    1998-12-31

    Different ventilation strategies to improve indoor air quality and to reduce HVAC system operating costs in a restaurant with nonsmoking and smoking areas and a bar are discussed in this paper. A generic sitting-type restaurant is used for the analysis. Prototype designs for the restaurant chain with more than 200 restaurants in different US climates were analyzed to collect the information on building envelope, dining area size, heat and contaminant sources and loads, occupancy rates, and current design practices. Four constant air volume HVAC systems wit h a constant and variable (demand-based) outdoor airflow rate, with a mixing and displacement air distribution, were compared in five representative US climates: cold (Minneapolis, MN); Maritime (Seattle, WA); moderate (Albuquerque, NM); hot-dry (Phoenix, AZ); and hot-humid (Miami, FL). For all four compared cases and climatic conditions, heating and cooling consumption by the HVAC system throughout the year-round operation was calculated and operation costs were compared. The analysis shows: Displacement air distribution allows for better indoor air quality in the breathing zone at the same outdoor air supply airflow rate due to contaminant stratification along the room height. The increase in outdoor air supply during the peak hours in Miami and Albuquerque results in an increase of both heating and cooling energy consumption. In other climates, the increase in outdoor air supply results in reduced cooling energy consumption. For the Phoenix, Minneapolis, and Seattle locations, the HVAC system operation with a variable outdoor air supply allows for a decrease in cooling consumption up to 50% and, in some cases, eliminates the use of refrigeration machines. The effect of temperature stratification on HVAC system parameters is the same for all locations; displacement ventilation systems result in decreased cooling energy consumption but increased heating consumption.

  18. VARIABLE TIME DELAY MEANS

    DOE Patents [OSTI]

    Clemensen, R.E.

    1959-11-01

    An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

  19. Variable Frequency Drives

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Marketing Toolkit The Benefits of Variable Frequency Drives (VFDs) VFDs help adjust motor speeds to match loads and improve efficiency while conserving energy. The benefits...

  20. Control Strategies for Centrifugal Pumps with Variable Flow Rate...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    This tip sheet discusses control strategies for centrifugal pumps with variable flow rate requirements in pumping systems and includes installation considerations. PUMPING SYSTEMS ...

  1. Variable orifice using an iris shutter

    DOE Patents [OSTI]

    Beeman, Raymond (El Cerrito, CA); Brajkovich, Steven J. (Fremont, CA)

    1978-01-01

    A variable orifice forming mechanism utilizing an iris shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow.

  2. Advanced Variable Speed Air-Source Integrated Heat Pump | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Pump Advanced Variable Speed Air-Source Integrated Heat Pump Advanced variable-speed Air Source Integrated Heat Pump prototype system and field test site near Knoxville, TN Credit: ...

  3. Variable capacity gasification burner

    SciTech Connect (OSTI)

    Saxon, D.I.

    1985-03-05

    A variable capacity burner that may be used in gasification processes, the burner being adjustable when operating in its intended operating environment to operate at two different flow capacities, with the adjustable parts being dynamically sealed within a statically sealed structural arrangement to prevent dangerous blow-outs of the reactants to the atmosphere.

  4. Synthesis of dimethyl ether and alternative fuels in the liquid phase from coal-derived synthesis gas. Task 2.2: Definition of preferred catalyst system; Task 2.3: Process variable scans on the preferred catalyst system; Task 2.4: Life-test on the preferred catalyst system

    SciTech Connect (OSTI)

    Bhatt, B.L.

    1992-09-01

    As part of the DOE-sponsored contract for the Synthesis of Dimethyl Ether (DME) and Alternative Fuels in the Liquid Phase from Coal- Derived Syngas, the single-step, slurry phase DME synthesis process was developed. The development involved screening of catalyst systems, process variable studies, and catalyst life studies in two 300 ml stirred autoclaves. As a spin-off of the Liquid Phase Methanol (LPMEOH*) process, the new process significantly improves the syngas conversion efficiency of the LPMEOH process. This improvement can be achieved by replacing a portion of methanol catalyst with a dehydration catalyst in the reactor, resulting in the product methanol being converted to DME, thus avoiding the thermodynamic equilibrium constraint of the methanol reaction. Overall, this increases syngas conversion per-pass. The selectivity and productivity of DME and methanol are affected by the catalyst system employed as well as operating conditions. A preferred catalyst system, consisting of a physical mixture of a methanol catalyst and a gamma alumina, was identified. An improvement of about 50% in methanol equivalent productivity was achieved compared to the LPMEOH process. Results from the process variable study indicate that higher pressure and CO{sub 2} removal benefit the process significantly. Limited life studies performed on the preferred catalyst system suggest somewhat higher than expected deactivation rate for the methanol catalyst. Several DME/methanol mixtures were measured for their key properties as transportation fuels. With small amounts of DME added, significant improvements in both flash points and Reid Vapor Pressure (RVP) were observed over the corresponding values of methanol alone.

  5. Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements

    Broader source: Energy.gov [DOE]

    This tip sheet discusses control strategies for centrifugal pumps with variable flow rate requirements in pumping systems and includes installation considerations.

  6. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  7. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  8. Variable laser attenuator

    DOE Patents [OSTI]

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  9. Variable Speed Pumping: A Guide to Successful Applications - Executive

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Summary | Department of Energy Variable Speed Pumping: A Guide to Successful Applications - Executive Summary Variable Speed Pumping: A Guide to Successful Applications - Executive Summary This document describes the cost and energy savings potential of pumping system applications with variable duty requirements. PDF icon Variable Speed Pumping: A Guide to Successful Applications - Executive Summary (May 2004) More Documents & Publications Energy Conservation Program: Test Procedure for

  10. Engine having a variable valve actuation system

    DOE Patents [OSTI]

    Hefler, Gregory W. (Chillicothe, IL)

    2005-10-12

    An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

  11. Engine having a variable valve actuation system

    DOE Patents [OSTI]

    Hefler, Gregory W. (Chillicothe, IL)

    2004-10-12

    An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

  12. Integrating Variable Renewable Energy: Challenges and Solutions

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.; Lew, D.

    2013-09-01

    In the U.S., a number of utilities are adopting higher penetrations of renewables, driven in part by state policies. While power systems have been designed to handle the variable nature of loads, the additional supply-side variability and uncertainty can pose new challenges for utilities and system operators. However, a variety of operational and technical solutions exist to help integrate higher penetrations of wind and solar generation. This paper explores renewable energy integration challenges and mitigation strategies that have been implemented in the U.S. and internationally, including forecasting, demand response, flexible generation, larger balancing areas or balancing area cooperation, and operational practices such as fast scheduling and dispatch.

  13. Radiograph and passive data analysis using mixed variable optimization

    Office of Scientific and Technical Information (OSTI)

    (Patent) | SciTech Connect Patent: Radiograph and passive data analysis using mixed variable optimization Citation Details In-Document Search Title: Radiograph and passive data analysis using mixed variable optimization Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography analysis. For example, certain embodiments perform radiographic analysis using mixed variable computation techniques. One exemplary system comprises a radiation

  14. Measuring spatial variability in soil characteristics

    DOE Patents [OSTI]

    Hoskinson, Reed L. (Rigby, ID); Svoboda, John M. (Idaho Falls, ID); Sawyer, J. Wayne (Hampton, VA); Hess, John R. (Ashton, ID); Hess, J. Richard (Idaho Falls, ID)

    2002-01-01

    The present invention provides systems and methods for measuring a load force associated with pulling a farm implement through soil that is used to generate a spatially variable map that represents the spatial variability of the physical characteristics of the soil. An instrumented hitch pin configured to measure a load force is provided that measures the load force generated by a farm implement when the farm implement is connected with a tractor and pulled through or across soil. Each time a load force is measured, a global positioning system identifies the location of the measurement. This data is stored and analyzed to generate a spatially variable map of the soil. This map is representative of the physical characteristics of the soil, which are inferred from the magnitude of the load force.

  15. Residential Cold Climate Heat Pump with Variable-Speed Technology |

    Energy Savers [EERE]

    Department of Energy Cold Climate Heat Pump with Variable-Speed Technology Residential Cold Climate Heat Pump with Variable-Speed Technology Purdue prototype system Purdue prototype system Unico concept prototype Unico concept prototype Purdue prototype system Unico concept prototype Lead Performer: Unico Systems - St. Louis, MO Partners: -- Oak Ridge National Laboratory - Oak Ridge, TN -- Purdue University - West Lafayette, IN -- Emerson Electric - St. Louis, MO -- Invention House - St.

  16. Initial testing of a variable-stroke Stirling engine

    SciTech Connect (OSTI)

    Thieme, L.G.

    1985-02-01

    In support of the US Department of Energy's Stirling Engine Highway Vehicle Systems Program, NASA Lewis Research Center is evaluating variable-stroke control for Stirling engines. The engine being tested is the Advenco Stirling engine; this engine was manufactured by Philips Research Laboratories of the Netherlands and uses a variable-angle swash-plate drive to achieve variable stroke operation. This report describes the engine, presents initial steady-state test data taken at Lewis, and describes a major drive system failure and subsequent modifications. Computer simulation results are presented to show potential part-load efficiency gains with variable-stroke control.

  17. Estimation and Control of Diesel Engine Processes Utilizing Variable Intake

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Valve Actuation | Department of Energy Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Air handling system model for multi-cylinder variable geometry turbocharged diesel engine with cooled EGR and flexible intake valve actuation developed to capture dynamic effects of gas exchange actuators PDF icon deer12_kocher.pdf More Documents & Publications Slide

  18. VariableR reclustering in multiple top quark events - Oral Presentatio...

    Office of Scientific and Technical Information (OSTI)

    VariableR reclustering in multiple top quark events - Oral Presentation Citation Details In-Document Search Title: VariableR reclustering in multiple top quark events - Oral...

  19. Role of Environmental Variability in Evaluating Stressor Effects

    SciTech Connect (OSTI)

    Luoma, Samuel N.; Clements, Will; Dewitt, Ted; Gerritsen, Jeroen; Hatch, Audrey; Jepson, Paul; Reynoldson, Trefor; Thom, Ronald M.

    2001-12-03

    In this chapter, we discuss how environmental variability affects the exposure of organisms and ecological systems to stressors, and give guidance on how to understand influences of stressors. We consider the characteristics of environmental variability and issues relating to the measurement of environmental variation. We discuss how to select the optimal indicators of ecological response in a variable natural environment. Finally, we suggest some approaches to incorporate environmental variability into resource management. In all cases we employ examples and case studies throughout to illustrate principles.

  20. Intensive Variables & Nanostructuring in Magnetostructural Materials

    SciTech Connect (OSTI)

    Lewis, Laura

    2014-08-13

    Over the course of this project, fundamental inquiry was carried out to investigate, understand and predict the effects of intensive variables, including the structural scale, on magnetostructural phase transitions in the model system of equiatomic FeRh. These transitions comprise simultaneous magnetic and structural phase changes that have their origins in very strong orbital-lattice coupling and thus may be driven by a plurality of effects.

  1. Present and Future Modes of Low Frequency Climate Variability

    SciTech Connect (OSTI)

    Cane, Mark A.

    2014-02-20

    This project addressed area (1) of the FOA, Interaction of Climate Change and Low Frequency Modes of Natural Climate Variability. Our overarching objective is to detect, describe and understand the changes in low frequency variability between model simulations of the preindustrial climate and simulations of a doubled CO2 climate. The deliverables are a set of papers providing a dynamical characterization of interannual, decadal, and multidecadal variability in coupled models with attention to the changes in this low frequency variability between pre-industrial concentrations of greenhouse gases and a doubling of atmospheric concentrations of CO2. The principle mode of analysis, singular vector decomposition, is designed to advance our physical, mechanistic understanding. This study will include external natural variability due to solar and volcanic aerosol variations as well as variability internal to the climate system. An important byproduct is a set of analysis tools for estimating global singular vector structures from the archived output of model simulations.

  2. TabVar: Tabulated Variables

    Energy Science and Technology Software Center (OSTI)

    2015-12-15

    TabVar: A Python library for manipulating datasets in the form of tabulated variables. Tables in tabvar contain many columns representing independent variables, but exactly one distinguished column for the dependent variable. Having a single distinguished column allows a natural lifting of arithmetic operators to tables, much (and in fact fully generalizing) multidimensional array arithmetic. The convenient syntax of whole-table arithmetic, along with the usual operations of filtering and aggregation, and all in the setting ofmore » python's interactive REPL allows for rapid exploration of datasets.« less

  3. Variable Speed Fan Retrofits for Computer Room Air Conditioners |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Variable Speed Fan Retrofits for Computer Room Air Conditioners Variable Speed Fan Retrofits for Computer Room Air Conditioners Case study describes various concepts for more cost-effective cooling solutions in data centers, while keeping in mind that the reliability of computing systems and their respective cooling systems is always a key criterion. PDF icon dc_fancasestudy.pdf More Documents & Publications Wireless Sensors Improve Data Center Efficiency NSIDC Data

  4. NREL: Transmission Grid Integration - Variability of Renewable Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sources Variability of Renewable Energy Sources Wind and solar energy are referred to as variable generation sources because their electricity production varies based on the availability of wind and sun. However, they are not the only source of variation in a power system. The demand for electricity, or load, also varies, and the power system was designed to handle that uncertainty. Short-term changes in load (over seconds or minutes) are generally small and caused by random events that

  5. Turbo-generator control with variable valve actuation

    DOE Patents [OSTI]

    Vuk, Carl T. (Denver, IA)

    2011-02-22

    An internal combustion engine incorporating a turbo-generator and one or more variably activated exhaust valves. The exhaust valves are adapted to variably release exhaust gases from a combustion cylinder during a combustion cycle to an exhaust system. The turbo-generator is adapted to receive exhaust gases from the exhaust system and rotationally harness energy therefrom to produce electrical power. A controller is adapted to command the exhaust valve to variably open in response to a desired output for the turbo-generator.

  6. Review of Variable Generation Integration Charges

    SciTech Connect (OSTI)

    Porter, K.; Fink, S.; Buckley, M.; Rogers, J.; Hodge, B. M.

    2013-03-01

    The growth of wind and solar generation in the United States, and the expectation of continued growth of these technologies, dictates that the future power system will be operated in a somewhat different manner because of increased variability and uncertainty. A small number of balancing authorities have attempted to determine an 'integration cost' to account for these changes to their current operating practices. Some balancing authorities directly charge wind and solar generators for integration charges, whereas others add integration charges to projected costs of wind and solar in integrated resource plans or in competitive solicitations for generation. This report reviews the balancing authorities that have calculated variable generation integration charges and broadly compares and contrasts the methodologies they used to determine their specific integration charges. The report also profiles each balancing authority and how they derived wind and solar integration charges.

  7. Thermoelectric power generator for variable thermal power source

    DOE Patents [OSTI]

    Bell, Lon E; Crane, Douglas Todd

    2015-04-14

    Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

  8. Experimental study on the floor-supply displacement ventilation system

    SciTech Connect (OSTI)

    Akimoto, Takashi; Nobe, Tatsuo; Takebayashi, Yoshihisa

    1995-12-31

    These results are presented from a research project to investigate the effects of a floor-supply displacement ventilation system with practical indoor heat loads. The experiments were performed in an experimental chamber (35.2 m{sup 2}) located in a controlled environment chamber. Temperature distributions were measured at seven heights throughout the experimental chamber for each test condition. Data were analyzed to observe thermal stratification as affected by lighting, occupants, and heat loads (personal computers), and its disruption caused by walking and change of air volume. In addition, airflow characteristics and ventilation efficiencies were investigated using a smoke machine, tobacco smoke, dust for industrial testing, and a tracer gas (CO{sub 2}) step-up procedure.

  9. Variable focal length deformable mirror

    DOE Patents [OSTI]

    Headley, Daniel (Albuquerque, NM); Ramsey, Marc (Albuquerque, NM); Schwarz, Jens (Albuquerque, NM)

    2007-06-12

    A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

  10. WECC Variable Generation Planning Reference Book

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-14

    This planning reference book is a document reflecting a Western Electricity Coordination Council (WECC) effort to put together multiple sources of information and provide a clear, systemic, comprehensive outline of the problems, both existing and anticipated; their impacts on the system; currently used and proposed solutions by the industry and research community; planning practices; new technologies, equipment, and standards; and expected future trends. This living (periodically updated) document could help WECC and other practicing engineers, especially the younger generation of engineers joining the workforce, to get familiar with a large variety of information related to the integration of variable resources into the WECC system, bypassing in part the need for time-consuming information gathering and learning processes from more experienced engineers or from the literature.

  11. WECC Variable Generation Planning Reference Book: Appendices

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-13

    The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

  12. Variable gas leak rate valve

    DOE Patents [OSTI]

    Eernisse, Errol P.; Peterson, Gary D.

    1976-01-01

    A variable gas leak rate valve which utilizes a poled piezoelectric element to control opening and closing of the valve. The gas flow may be around a cylindrical rod with a tubular piezoelectric member encircling the rod for seating thereagainst to block passage of gas and for reopening thereof upon application of suitable electrical fields.

  13. Market Designs for High Levels of Variable Generation: Preprint

    SciTech Connect (OSTI)

    Milligan, M.; Holttinen, H.; Kiviluoma, J.; Orths, A.; Lynch, M.; Soder, L.

    2014-10-01

    Variable renewable generation is increasing in penetration in modern power systems, leading to higher variability in the supply and price of electricity as well as lower average spot prices. This raises new challenges, particularly in ensuring sufficient capacity and flexibility from conventional technologies. Because the fixed costs and lifetimes of electricity generation investments are significant, designing markets and regulations that ensure the efficient integration of renewable generation is a significant challenge. This papers reviews the state of play of market designs for high levels of variable generation in the United States and Europe and considers new developments in both regions.

  14. May 2013 PSERC Webinar: Managing Wind Variability with Self-Reserves...

    Energy Savers [EERE]

    The DOE-funded Power Systems Engineering Research Center (PSERC) is offering a free public webinar on managing wind variability in energy production. The webinar will be held ...

  15. Market Characteristics for Efficient Integration of Variable Generation in the Western Interconnection

    SciTech Connect (OSTI)

    Milligan, M.; Kirby, B.

    2010-08-01

    The overriding purpose of this report is to establish the physical requirements of a power system that can accommodate high levels of variable generation.

  16. Variable frequency microwave heating apparatus

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

    1999-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  17. Sandia defines solar variability zones

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    defines solar variability zones - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs

  18. Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon Advanced Variable Speed Integrated Heat Pump - 2013 Peer Review Presentation More Documents & Publications Advanced variable-speed Air Source Integrated Heat Pump prototype system and field test site near Knoxville, TN Credit: Oak Ridge National Lab Advanced Variable Speed

  19. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, C.M.

    1998-12-15

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine is described. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod. 8 figs.

  20. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, Carsten M. (Dadeville, AL)

    1998-01-01

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod.

  1. Variable Average Absolute Percent Differences

    Gasoline and Diesel Fuel Update (EIA)

    Variable Average Absolute Percent Differences Percent of Projections Over- Estimated Gross Domestic Product Real Gross Domestic Product (Average Cumulative Growth)* (Table 2) 0.9 45.8 Petroleum Imported Refiner Acquisition Cost of Crude Oil (Constant $) (Table 3a) 37.7 17.3 Imported Refiner Acquisition Cost of Crude Oil (Nominal $) (Table 3b) 36.6 18.7 Total Petroleum Consumption (Table 4) 7.9 70.7 Crude Oil Production (Table 5) 8.1 51.1 Petroleum Net Imports (Table 6) 24.7 73.8 Natural Gas

  2. HCCI in a Variable Compression Ratio Engine: Effects of Engine...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in a Variable Compression Ratio Engine: Effects of Engine Variables HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables 2004 Diesel Engine Emissions Reduction ...

  3. CBEI: Pre-commercial demonstration of cost-effective advanced...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sized Commercial Buildings - 2015 Peer Review Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant...

  4. CBEI: AHU FDD in Small and Medium Sized Commercial Buildings...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    - 2015 Peer Review More Documents & Publications Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant...

  5. Variable flexure-based fluid filter

    DOE Patents [OSTI]

    Brown, Steve B.; Colston, Jr., Billy W.; Marshall, Graham; Wolcott, Duane

    2007-03-13

    An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

  6. SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418

    SciTech Connect (OSTI)

    Johnson, F.; Edwards, T.

    2010-11-29

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of thermal history. All of the normalized boron releases were less than 1 g/L. While all of the targeted glass compositions were predictable with respect to the Product Composition Control System (PCCS) models for durability, a small number of the measured glass compositions were located outside of the lower prediction limit indicating poorer durability than what was actually measured. These unpredictable glasses were in the same lithium metaborate (LM) preparation block during the chemical analyses, which resulted in measured compositions that were not representative of the target compositions. A review of the data did not indicate a clear cause for the problem. Re-digestion and re-measurement of three glasses from this preparation block yielded glass compositions closer to the target values and predicted PCT responses within the PCCS model uncertainty. Therefore, it is believed that the glasses were correctly fabricated and the targeted compositions are closer representations of the true compositions. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable for the SB6/Frit 418 glass system. PCT results from the glasses fabricated as part of the variability study were shown to be predictable and/or acceptable with respect to the DWPF PCCS models. In addition, the inclusion of ThO{sub 2} was shown to have minimal impact on the acceptability and predictability of the variability study glasses.

  7. Variable delivery, fixed displacement pump

    DOE Patents [OSTI]

    Sommars, Mark F. (Sparland, IL)

    2001-01-01

    A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

  8. Variable ratio regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  9. Continuously variable focal length lens

    DOE Patents [OSTI]

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  10. Variable residence time vortex combustor

    DOE Patents [OSTI]

    Melconian, Jerry O.

    1987-01-01

    A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

  11. Evaluation of Longitudinal Variabler in Relativistic Accelerators

    Energy Science and Technology Software Center (OSTI)

    1995-07-13

    ELVIRA is an encoding of an analytical formula to the calculation of longitudinal dynamics variable evolution during an accelerator ramp.

  12. Variable-energy drift-tube linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

    1984-01-01

    A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a variable-energy drift-tube linear accelerator.

  13. Application Performance Variability on Hopper

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the system. All images and graphs can be viewed in full size by clicking on them. Visual Example The below graphic shows a visual picture of node placement for the MILC...

  14. Variable path length spectrophotometric probe

    DOE Patents [OSTI]

    O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

    1992-01-01

    A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

  15. Control device of an infinitely variable transmission

    SciTech Connect (OSTI)

    Tanaka, H.

    1987-01-27

    An automatic control system is described for a toric type infinitely variable transmission of a running vehicle, the speed of which is changed by varying a gear ratio corresponding to a running mode of the vehicle selected by a driver. The transmission comprises coaxially disposed input and output shafts with input and output disks having toroidal surfaces and respectively secured to the input and output shafts, a traction roller engaged with the toroidal surfaces of the disks, and a trunnion rotatably supporting the traction roller on a rotary shaft. The trunnion is linearly movable in the direction of a pivot axis which is perpendicular to the rotary shaft of the traction roller and is pivotable around the pivot axis so that the gear ratio between the input shaft and the output shaft may be changed. The control system comprises: a hydraulic cylinder receiving an axial end of the trunnion; and a hydraulic circuit connecting the hydraulic cylinder with a hydraulic source, the hydraulic circuit including a solenoid valve. The valve has means for repeatedly opening and closing the valve at predetermined intervals and controlling hydraulic supply to the hydraulic cylinder and thereby controlling the linear movement of the trunnion in the direction of the pivot axis so as to vary the gear ratio.

  16. Integration of Variable Generation and Cost-Causation (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-09-01

    Variable renewable energy generation sources, such as wind and solar energy, provide benefits such as reduced environmental impact, zero fuel consumption, and low and stable costs. Advances in both technologies can reduce capital costs and provide significant control capabilities. However, their variability and uncertainty - which change with weather conditions, time of day, and season - can cause an increase in power system operating costs compared to a fully controllable power plant. Although a number of studies have assessed integration costs, calculating them correctly is challenging because it is difficult to accurately develop a baseline scenario without variable generation that properly accounts for the energy value. It is also difficult to appropriately allocate costs given the complex, nonlinear interactions between resources and loads.

  17. VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Citation Details In-Document Search Title: VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the presence of circumstellar gas in the progenitor system prior to the explosion, with significant

  18. Variable Compression Ratio Engine | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Compression Ratio Engine Variable Compression Ratio Engine 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. PDF icon ace_43_mendler.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: High Efficiency VCR Engine with Variable Valve Actuation and new Supercharging Technology Vehicle Technologies Office Merit Review 2015: High Efficiency VCR Engine with Variable Valve

  19. Eccentric crank variable compression ratio mechanism

    DOE Patents [OSTI]

    Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

    2008-05-13

    A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

  20. WIND VARIABILITY IN BZ CAMELOPARDALIS

    SciTech Connect (OSTI)

    Honeycutt, R. K.; Kafka, S.; Robertson, J. W. E-mail: skafka@dtm.ciw.edu

    2013-02-01

    Sequences of spectra of the nova-like cataclysmic variable (CV) BZ Cam were acquired on nine nights in 2005-2006 in order to study the time development of episodes of wind activity known to occur frequently in this star. We confirm the results of Ringwald and Naylor that the P-Cygni absorption components of the lines mostly evolve from higher expansion velocity to lower velocity as an episode progresses. We also commonly find blueshifted emission components in the H{alpha} line profile, whose velocities and durations strongly suggest that they are also due to the wind. Curiously, Ringwald and Naylor reported common occurrences of redshifted H{alpha} emission components in their BZ Cam spectra. We have attributed these emission components in H{alpha} to occasions when gas concentrations in the bipolar wind (both front side and back side) become manifested as emission lines as they move beyond the disk's outer edge. We also suggest, based on changes in the P-Cygni profiles during an episode, that the progression from larger to smaller expansion velocities is due to the higher velocity portions of a wind concentration moving beyond the edge of the continuum light of the disk first, leaving a net redward shift of the remaining absorption profile. We derive a new orbital ephemeris for BZ Cam, using the radial velocity of the core of the He I {lambda}5876 line, finding P = 0.15353(4). Using this period, the wind episodes in BZ Cam are found to be concentrated near the inferior conjunction of the emission line source. This result helps confirm that the winds in nova-like CVs are often phase dependent, in spite of the puzzling implication that such winds lack axisymmetry. We argue that the radiation-driven wind in BZ Cam receives an initial boost by acting on gas that has been lifted above the disk by the interaction of the accretion stream with the disk, thereby imposing flickering timescales onto the wind events, as well as leading to an orbital modulation of the wind due to the non-axisymmetric nature of the stream/disk interaction. Simultaneous photometry and spectroscopy were acquired on three nights in order to test the possible connection between flickering continuum light and the strength of the front-side wind. We found strong agreement on one night, some agreement on another, and no agreement on the third. We suggest that some flickering events lead to only back-side winds which will not have associated P-Cygni profiles.

  1. Variables Affecting Economic Development of Wind Energy

    SciTech Connect (OSTI)

    Lantz, E.; Tegen, S.

    2008-02-01

    Report on the specific factors driving wind-power-related economic development and on the impact of specific economic development variables on new wind project economic benefits.

  2. Variable-Period Undulators For Synchrotron Radiation

    DOE Patents [OSTI]

    Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  3. Compact, electro-hydraulic, variable valve actuation system providing...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Step change in Fuel Efficiency:Eaton's perspective Development of High-Efficiency Clean Combustion Engines Designs for SI and CI Engines High Efficiency Clean Combustion Engine ...

  4. Strategies and Decision Support Systems for Integrating Variable...

    Open Energy Info (EERE)

    Centers for Reliable Grid Operations: Global Best Practices, Examples of Excellence and Lessons Learned Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Strategies and...

  5. Measuring quasar variability with Pan-STARRS1 and SDSS

    SciTech Connect (OSTI)

    Morganson, E.; Rix, H.-W.; Schlafly, E. F.; Walter, F.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Magnier, E. A.; Morgan, J. S.; Tonry, J. L.; Green, P. J.; Marshall, P. J.; Price, P. A.

    2014-04-01

    We measure quasar variability using the Panoramic Survey Telescope and Rapid Response System 1 Survey (Pan-STARRS1 or PS1) and the Sloan Digital Sky Survey (SDSS) and establish a method of selecting quasars via their variability in 10{sup 4} deg{sup 2} surveys. We use 10{sup 5} spectroscopically confirmed quasars that have been well measured in both PS1 and SDSS and take advantage of the decadal timescales that separate SDSS measurements and PS1 measurements. A power law model fits the data well over the entire time range tested, 0.01-10 yr. Variability in the current PS1-SDSS data set can efficiently distinguish between quasars and nonvarying objects. It improves the purity of a griz quasar color cut from 4.1% to 48% while maintaining 67% completeness. Variability will be very effective at finding quasars in data sets with no u band and in redshift ranges where exclusively photometric selection is not efficient. We show that quasars' rest-frame ensemble variability, measured as a root mean squared in ? magnitudes, is consistent with V(z, L, t) = A {sub 0}(1 + z){sup 0.37}(L/L {sub 0}){sup 0.16}(t/1 yr){sup 0.246}, where L {sub 0} = 10{sup 46} erg s{sup 1} and A {sub 0} = 0.190, 0.162, 0.147, or 0.141 in the g {sub P1}, r {sub P1}, i {sub P1}, or z {sub P1}filter, respectively. We also fit across all four filters and obtain median variability as a function of z, L, and ? as V(z, L, ?, t) = 0.079(1 + z){sup 0.15}(L/L {sub 0}){sup 0.2}(?/1000 nm){sup 0.44}(t/1 yr){sup 0.246}.

  6. Variability of Load and Net Load in Case of Large Scale Distributed Wind Power

    SciTech Connect (OSTI)

    Holttinen, H.; Kiviluoma, J.; Estanqueiro, A.; Gomez-Lazaro, E.; Rawn, B.; Dobschinski, J.; Meibom, P.; Lannoye, E.; Aigner, T.; Wan, Y. H.; Milligan, M.

    2011-01-01

    Large scale wind power production and its variability is one of the major inputs to wind integration studies. This paper analyses measured data from large scale wind power production. Comparisons of variability are made across several variables: time scale (10-60 minute ramp rates), number of wind farms, and simulated vs. modeled data. Ramp rates for Wind power production, Load (total system load) and Net load (load minus wind power production) demonstrate how wind power increases the net load variability. Wind power will also change the timing of daily ramps.

  7. The Taiwanese-American occultation survey project stellar variability. III. Detection of 58 new variable stars

    SciTech Connect (OSTI)

    Ishioka, R.; Wang, S.-Y.; Zhang, Z.-W.; Lehner, M. J.; Cook, K. H.; King, S.-K.; Lee, T.; Marshall, S. L.; Schwamb, M. E.; Wang, J.-H.; Wen, C.-Y.; Alcock, C.; Protopapas, P.; Axelrod, T.; Bianco, F. B.; Byun, Y.-I.; Chen, W. P.; Ngeow, C.-C.; Kim, D.-W.; Rice, J. A.

    2014-04-01

    The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg{sup 2} field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 ? Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.

  8. Temperature System

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 Soil Water and Temperature System  SWATS In the realm of global climate modeling, numerous variables affect the state of the atmosphere and climate. One important area is soil moisture and temperature. The ARM Program uses several types of instruments to gather soil moisture information. An example is the soil water and temperature system (SWATS) (Figure 1). A SWATS is located at each of 21 extended facility sites within the CART site boundary. Each system is configured to measure soil

  9. HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy in a Variable Compression Ratio Engine: Effects of Engine Variables HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Southwest Research Institute PDF icon 2004_deer_ryan.pdf More Documents & Publications HCCI - A Technical Review and Progress Report 2006 HCCI - Update of Progress 2005 Fuel Requirements for HCCI Engine Operation

  10. Sensors and Controls Reports | Department of Energy

    Energy Savers [EERE]

    Emerging Technologies » Sensors and Controls R&D » Sensors and Controls Reports Sensors and Controls Reports Sensor Characteristics Reference Guide (PNNL, April 2013) Energy Savings for Occupancy-Based Control (OBC) of Variable-Air-Volume (VAV) Systems (PNNL, Jan 2013) Small- and Medium-Sized Commercial Building Monitoring and Controls Needs: A Scoping Study (PNNL, Oct 2012) Buildings Home About Emerging Technologies HVAC, Water Heating, Appliances R&D Windows and Building Envelope

  11. The Impact of Soil Sampling Errors on Variable Rate Fertilization

    SciTech Connect (OSTI)

    R. L. Hoskinson; R C. Rope; L G. Blackwood; R D. Lee; R K. Fink

    2004-07-01

    Variable rate fertilization of an agricultural field is done taking into account spatial variability in the soils characteristics. Most often, spatial variability in the soils fertility is the primary characteristic used to determine the differences in fertilizers applied from one point to the next. For several years the Idaho National Engineering and Environmental Laboratory (INEEL) has been developing a Decision Support System for Agriculture (DSS4Ag) to determine the economically optimum recipe of various fertilizers to apply at each site in a field, based on existing soil fertility at the site, predicted yield of the crop that would result (and a predicted harvest-time market price), and the current costs and compositions of the fertilizers to be applied. Typically, soil is sampled at selected points within a field, the soil samples are analyzed in a lab, and the lab-measured soil fertility of the point samples is used for spatial interpolation, in some statistical manner, to determine the soil fertility at all other points in the field. Then a decision tool determines the fertilizers to apply at each point. Our research was conducted to measure the impact on the variable rate fertilization recipe caused by variability in the measurement of the soils fertility at the sampling points. The variability could be laboratory analytical errors or errors from variation in the sample collection method. The results show that for many of the fertility parameters, laboratory measurement error variance exceeds the estimated variability of the fertility measure across grid locations. These errors resulted in DSS4Ag fertilizer recipe recommended application rates that differed by up to 138 pounds of urea per acre, with half the field differing by more than 57 pounds of urea per acre. For potash the difference in application rate was up to 895 pounds per acre and over half the field differed by more than 242 pounds of potash per acre. Urea and potash differences accounted for almost 87% of the cost difference. The sum of these differences could result in a $34 per acre cost difference for the fertilization. Because of these differences, better analysis or better sampling methods may need to be done, or more samples collected, to ensure that the soil measurements are truly representative of the fields spatial variability.

  12. Lithium battery management system

    DOE Patents [OSTI]

    Dougherty, Thomas J. (Waukesha, WI)

    2012-05-08

    Provided is a system for managing a lithium battery system having a plurality of cells. The battery system comprises a variable-resistance element electrically connected to a cell and located proximate a portion of the cell; and a device for determining, utilizing the variable-resistance element, whether the temperature of the cell has exceeded a predetermined threshold. A method of managing the temperature of a lithium battery system is also included.

  13. PV output variability modeling using satellite imagery.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Reno, Matthew J.

    2010-11-01

    High frequency irradiance variability measured on the ground is caused by the formation, dissipation, and passage of clouds in the sky. If we can identify and associate different cloud types/patterns from satellite imagery, we may be able to predict irradiance variability in areas lacking sensors. With satellite imagery covering the entire U.S., this allows for more accurate integration planning and power flow modeling over wide areas. Satellite imagery from southern Nevada was analyzed at 15 minute intervals over a year. Methods for image stabilization, cloud detection, and textural classification of clouds were developed and tested. High Performance Computing parallel processing algorithms were also investigated and tested. Artificial Neural Networks using imagery as inputs were trained on ground-based measurements of irradiance to model the variability and were tested to show some promise as a means for predicting irradiance variability.

  14. Residential Variable-Capacity Heat Pumps Sized to Heating Loads

    SciTech Connect (OSTI)

    Munk, Jeffrey D.; Jackson, Roderick K.; Odukomaiya, Adewale; Gehl, Anthony C.

    2014-01-01

    Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in the cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.

  15. Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-10-01

    Many countries--reflecting very different geographies, markets, and power systems--are successfully managing high levels of variable renewable energy (RE) on the grid. Australia (South Australia), Denmark, Germany, Ireland, Spain, and the United States (Colorado and Texas), for example, have effectively integrated variable RE utilizing diverse approaches. Analysis of the results from these case studies reveals a wide range of mechanisms that can be used to accommodate high penetrations of variable RE (e.g., from new market designs to centralized planning). Nevertheless, the myriad approaches collectively suggest that governments can best enable variable RE grid integration by implementing best practices in five areas of intervention: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations.

  16. VariableR Reclustering in Multiple Top Quark and W Boson Events

    SciTech Connect (OSTI)

    Hyde, Jeremy

    2015-08-14

    VariableR jet reclustering is an innovative technique that allows for the reconstruction of boosted object over a wide range of kinematic regimes. Such capability enables the efficient identification of events with multiple boosted top quarks which is a typical signature for new physics processes such as the production of the supersymmetric partner of the gluon. In order to evaluate the performance of the algorithm, the VariableR reclustered jets are compared with fixed radius reclustered jets. The flexibility of the algorithm is tested by reconstructing both boosted top quarks and boosted W bosons. The VariableR reclustering method is found to be more efficient than the fixed radius algorithm at identifying top quarks and W bosons in events with four top quarks, therefore enhancing the sensitivity for gluino searches.

  17. Potential Reductions in Variability with Alternative Approaches to Balancing Area Cooperation with High Penetrations of Variable Generation

    SciTech Connect (OSTI)

    Milligan, M.; Kirby, B.; Beuning, S.

    2010-08-01

    The work described in this report was performed by the National Renewable Energy Laboratory (NREL) and funded by the Office of the Energy Efficiency and Renewable Energy, U.S. Department of Energy (EERE DOE). This project is a joint project with the Pacific Northwest National Laboratory. This report evaluates the physical characteristics that improve the ability of the power system to absorb variable generation. It then uses evidence from electricity markets in the Eastern Interconnection of the United States to show how large, fast energy markets can help with integration. The concept of Virtual Balancing Area is introduced, a concept that covers a broad range of cooperative measures that can be undertaken by balancing areas to help manage variability.

  18. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, O.A.

    1988-07-13

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90/degree/ intervals with opposing electrodes maintained at the same potential. 12 figs., 3 tabs.

  19. Polymer performance in cooling water: The influence of process variables

    SciTech Connect (OSTI)

    Amjad, Z.; Pugh, J.; Zibrida, J.; Zuhl, B.

    1997-01-01

    The key to the efficacy of phosphate and phosphonates in stabilized phosphate and all-organic cooling water treatment (CWT) programs is the presence and performance of polymeric inhibitors/dispersants. The performance of polymeric additives used in CWT programs can be adversely impacted by the presence of iron, phosphonate, or cationic polymer and influenced by a variety of process variables including system pH and temperature. In this article, the performance of several polymeric additives is evaluated under a variety of stressed conditions.

  20. The variable sky of deep synoptic surveys

    SciTech Connect (OSTI)

    Ridgway, Stephen T.; Matheson, Thomas; Mighell, Kenneth J.; Olsen, Knut A. [National Optical Astronomy Observatory, Tucson, AZ 85725 (United States); Howell, Steve B., E-mail: ridgway@noao.edu [NASA Ames Research Center, P.O. Box 1, M/S 244-30, Moffett Field, CA 94035 (United States)

    2014-11-20

    The discovery of variable and transient sources is an essential product of synoptic surveys. The alert stream will require filtering for personalized criteriaa process managed by a functionality commonly described as a Broker. In order to understand quantitatively the magnitude of the alert generation and Broker tasks, we have undertaken an analysis of the most numerous types of variable targets in the skyGalactic stars, quasi-stellar objects (QSOs), active galactic nuclei (AGNs), and asteroids. It is found that the Large Synoptic Survey Telescope (LSST) will be capable of discovering ?10{sup 5} high latitude (|b| > 20) variable stars per night at the beginning of the survey. (The corresponding number for |b| < 20 is orders of magnitude larger, but subject to caveats concerning extinction and crowding.) However, the number of new discoveries may well drop below 100 per night within less than one year. The same analysis applied to GAIA clarifies the complementarity of the GAIA and LSST surveys. Discovery of AGNs and QSOs are each predicted to begin at ?3000 per night and decrease by 50 times over four years. Supernovae are expected at ?1100 per night, and after several survey years will dominate the new variable discovery rate. LSST asteroid discoveries will start at >10{sup 5} per night, and if orbital determination has a 50% success rate per epoch, they will drop below 1000 per night within two years.

  1. Chapter 18: Variable Frequency Drive Evaluation Protocol

    SciTech Connect (OSTI)

    Romberger, J.

    2014-11-01

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  2. Galactic Variable Sky with EGRET and GLAST

    SciTech Connect (OSTI)

    Digel, S.W.; /SLAC

    2006-11-28

    The characteristics of the largely-unidentified Galactic sources of gamma rays that were detected by EGRET are reviewed. Proposed source populations that may have the correct spatial, spectral, luminosity, and variability properties to be the origins of the EGRET sources are also presented. Finally, the prospects for studying Galactic gamma-ray sources with the GLAST LAT are reviewed.

  3. Storage of LWR spent fuel in air: Volume 1: Design and operation of a spent fuel oxidation test facility

    SciTech Connect (OSTI)

    Thornhill, C.K.; Campbell, T.K.; Thornhill, R.E.

    1988-12-01

    This report describes the design and operation and technical accomplishments of a spent-fuel oxidation test facility at the Pacific Northwest Laboratory. The objective of the experiments conducted in this facility was to develop a data base for determining spent-fuel dry storage temperature limits by characterizing the oxidation behavior of light-water reactor (LWR) spent fuels in air. These data are needed to support licensing of dry storage in air as an alternative to spent-fuel storage in water pools. They are to be used to develop and validate predictive models of spent-fuel behavior during dry air storage in an Independent Spent Fuel Storage Installation (ISFSI). The present licensed alternative to pool storage of spent fuel is dry storage in an inert gas environment, which is called inerted dry storage (IDS). Licensed air storage, however, would not require monitoring for maintenance of an inert-gas environment (which IDS requires) but does require the development of allowable temperature limits below which UO/sub 2/ oxidation in breached fuel rods would not become a problem. Scoping tests at PNL with nonirradiated UO/sub 2/ pellets and spent-fuel fragment specimens identified the need for a statistically designed test matrix with test temperatures bounding anticipated maximum acceptable air-storage temperatures. This facility was designed and operated to satisfy that need. 7 refs.

  4. Variable Speed Pumping: A Guide to Successful Applications -...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Variable Speed Pumping: A Guide to Successful Applications - Executive Summary Variable Speed Pumping: A Guide to Successful Applications - Executive Summary This document ...

  5. Control Strategies for Centrifugal Pumps with Variable Flow Rate...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements This tip sheet discusses...

  6. Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open...

    Open Energy Info (EERE)

    3-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing...

  7. Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open...

    Open Energy Info (EERE)

    is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing...

  8. Self-Referenced Continuous-Variable Quantum Key Distribution...

    Office of Scientific and Technical Information (OSTI)

    Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Citation Details In-Document Search Title: Self-Referenced Continuous-Variable Quantum Key Distribution ...

  9. Estimation and Control of Diesel Engine Processes Utilizing Variable...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve ...

  10. Enabling High Efficiency Clean Combustion with Micro-Variable...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Enabling High Efficiency Clean Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel ...

  11. Adaptive PCCI with Variable Orifice Injector for Low Cost High...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels ...

  12. May 2013 PSERC Webinar: Managing Wind Variability with Self-Reserves and

    Office of Environmental Management (EM)

    Responsive Demand | Department of Energy 3 PSERC Webinar: Managing Wind Variability with Self-Reserves and Responsive Demand May 2013 PSERC Webinar: Managing Wind Variability with Self-Reserves and Responsive Demand April 9, 2013 - 10:40am Addthis The DOE-funded Power Systems Engineering Research Center (PSERC) is offering a free public webinar on managing wind variability in energy production. The webinar will be held Tuesday, May 7, 2013 from 2-3 p.m. No pre-registration is necessary.

  13. Advanced variable speed air-source integrated heat pump (AS-IHP)

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Advanced variable speed air-source integrated heat pump (AS-IHP) 2014 Building Technologies Office Peer Review Field test system IHP concept - all HVAC/WH integrated into one highly efficient system Van D. Baxter, vdb@ornl.gov Oak Ridge National Laboratory Project Summary Timeline: Advanced variable speed air-source integrated heat pump (AS-IHP) - CRADA Start date: 01-Oct-2011 Planned end date: 31-Dec-2015 Key Milestones 1.Complete system lab tests for model calibration; 31-July-2013 2.Complete

  14. The Kelastic variable wall mining machine. Interim final report

    SciTech Connect (OSTI)

    1995-11-12

    This machine cuts coal along a longwall face extending up to 500 feet by a rotating auger with bits. The machine also transports the coal that is cut acting as screw conveyor. By virtue of an integral shroud comprising part of the conveyor the machine is also amenable to a separation of the zones where men work from air being contaminated by dust and methane gas by the cutting action. Beginning as single intake air courses, the air separates at the working section where one split provides fresh air to the Occupied Zone (OZ) for human needs and the other split purges and carries away dust and methane from face fragmentation in the Cutting Zone (CZ). The attractiveness of the Variable Wall Mining Machine is that it addresses the limitations of current longwall mining equipment: it can consistently out-produce continuous mining machines and most longwall shearing machines. It also is amenable to configuring an environment, the dual-duct system, where the air for human breathing is separated from dust-laden ventilating air with methane mixtures. The objective of the research was to perform a mathematical and experimental study of the interrelationships of the components of the system so that a computer model could demonstrate the workings of the system in an animation program. The analysis resulted in the compilation of the parameters for three different configurations of a dual aircourse system of ventilating underground mines. In addressing the goal of an inherently safe mining system the dual-duct adaptation to the Variable Wall Mining Machine appears to offer the path to solution. The respirable dust problem is solvable; the explosive dust problem is nearly solvable; and the explosive methane problem can be greatly reduced. If installed in a highly gassy mine, the dual duct models would also be considerably less costly.

  15. Thermodynamics in variable speed of light theories

    SciTech Connect (OSTI)

    Racker, Juan [CONICET, Centro Atomico Bariloche, Avenida Bustillo 9500 (8400), San Carlos De Bariloche (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina); Sisterna, Pablo [Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600), Mar del Plata (Argentina); Vucetich, Hector [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina)

    2009-10-15

    The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light (c), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of c is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

  16. Variable aperture collimator for high energy radiation

    DOE Patents [OSTI]

    Hill, Ronald A. (Albuquerque, NM)

    1984-05-22

    An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated energy from emerging from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

  17. Radiograph and passive data analysis using mixed variable optimization

    DOE Patents [OSTI]

    Temple, Brian A.; Armstrong, Jerawan C.; Buescher, Kevin L.; Favorite, Jeffrey A.

    2015-06-02

    Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography analysis. For example, certain embodiments perform radiographic analysis using mixed variable computation techniques. One exemplary system comprises a radiation source, a two-dimensional detector for detecting radiation transmitted through a object between the radiation source and detector, and a computer. In this embodiment, the computer is configured to input the radiographic image data from the two-dimensional detector and to determine one or more materials that form the object by using an iterative analysis technique that selects the one or more materials from hierarchically arranged solution spaces of discrete material possibilities and selects the layer interfaces from the optimization of the continuous interface data.

  18. Sandia Labs releases wavelet variability model (WVM)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    releases wavelet variability model (WVM) - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management

  19. Integrating Variable Renewable Energy: Challenges and Solutions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Integrating Variable Renewable Energy: Challenges and Solutions L. Bird, M. Milligan, and D. Lew National Renewable Energy Laboratory Technical Report NREL/TP-6A20-60451 September 2013 NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency & Renewable Energy Operated by the Alliance for Sustainable Energy, LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. Contract No.

  20. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, Oscar A. (Berkeley, CA)

    1990-01-01

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90.degree. intervals with opposing electrodes maintained at the same potential. Adjacent cylinder electrodes of the quadrupole structure are maintained at different potentials to thereby reshape the cross section of the charged particle beam to an ellipse in cross section at the mid point along each quadrupole electrode unit in the accelerator modules. The beam is maintained in focus by alternating the major axis of the ellipse along the x and y axis respectively at adjacent quadrupoles. In another embodiment, electrostatic ring electrodes may be utilized instead of the quadrupole electrodes.

  1. Variable diameter wind turbine rotor blades

    DOE Patents [OSTI]

    Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

    2005-12-06

    A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

  2. HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY

    SciTech Connect (OSTI)

    Fox, K; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I; Phyllis Workman, P

    2006-10-02

    The Defense Waste Processing Facility (DWPF) is preparing for vitrification of High Level Waste (HLW) Sludge Batch 4 (SB4) in early FY2007. To support this process, the Savannah River National Laboratory (SRNL) has provided a recommendation to utilize Frit 503 for vitrifying this sludge batch, based on the composition projection provided by the Liquid Waste Organization on June 22, 2006. Frit 418 was also recommended for possible use during the transition from SB3 to SB4. A critical step in the SB4 qualification process is to demonstrate the applicability of the durability models, which are used as part of the DWPF's process control strategy, to the glass system of interest via a variability study. A variability study is an experimentally-driven assessment of the predictability and acceptability of the quality of the vitrified waste product that is anticipated from the processing of a sludge batch. At the DWPF, the durability of the vitrified waste product is not directly measured. Instead, the durability is predicted using a set of models that relate the Product Consistency Test (PCT) response of a glass to the chemical composition of that glass. In addition, a glass sample is taken during the processing of that sludge batch, the sample is transmitted to SRNL, and the durability is measured to confirm acceptance. The objective of a variability study is to demonstrate that these models are applicable to the glass composition region anticipated during the processing of the sludge batch - in this case the Frit 503 - SB4 compositional region. The success of this demonstration allows the DWPF to confidently rely on the predictions of the durability/composition models as they are used in the control of the DWPF process.

  3. THE ENIGMATIC YOUNG, LOW-MASS VARIABLE TWA 30

    SciTech Connect (OSTI)

    Looper, Dagny L.; Rayner, John; Pitts, Mark A.; Mohanty, Subhanjoy; Bochanski, John J.; Burgasser, Adam J.; Mamajek, Eric E.; Herczeg, Gregory J.; West, Andrew A.; Faherty, Jacqueline K.; Kirkpatrick, J. Davy

    2010-05-01

    TWA 30 is a remarkable young (7 {+-} 3 Myr), low-mass (0.12 {+-} 0.04 M{sub sun}), late-type star (M5 {+-} 1) residing 42 {+-} 2 pc away from the Sun in the TW Hydrae Association (TWA). It shows strong outflow spectral signatures such as [S II], [O I], [O II], [O III], and Mg I], while exhibiting weak H{alpha} emission (-6.8 {+-} 1.2 A). Emission lines of [S II] and [O I] are common to T Tauri stars still residing in their natal molecular clouds, while [O III] and Mg I] emission lines are incredibly rare in this same population; in the case of TWA 30, these latter lines may arise from new outflow material colliding into older outflow fronts. The weak H{alpha} emission and small radial velocity shifts of line emission relative to the stellar frame of rest (generally {approx_lt}10 km s{sup -1}) suggest that the disk is viewed close to edge-on and that the stellar axis may be inclined to the disk, similar to the AA Tau system, based on its temporal changes in emission/absorption line strengths/profiles and variable reddening (A{sub V} = 1.5-9.0). The strong Li absorption (0.61 {+-} 0.13 A) and common kinematics with members of the TWA confirm its age and membership to the association. Given the properties of this system such as its proximity, low mass, remarkable outflow signatures, variability, and edge-on configuration, this system is a unique case study at a critical time in disk evolution and planet-building processes.

  4. Variability in continuous traffic monitoring data

    SciTech Connect (OSTI)

    Wright, T.; Hu, P.S.; Young, J.

    1996-07-01

    Each state in the United States can be viewed as a universe of road segments. For each road segment in each state, it is desired to know various traffic characteristics based on count data, classification count data, and weigh-in-motion data. These data are absolutely essential for highway design, maintenance, safety, and planning. Given no cost constraints, each road segment would be continuously monitored every day of the year. However, in practice, a few road segments are monitored continuously every day of the year to produce annual characteristics of traffic flow. The remaining road segments are monitored for one or two days each year, and this resulting data are `adjusted` (using factors based on data collected from the continuously monitored road segments) to produce estimates of annual characteristics. With this general approach, each state strives to provide estimates of annual characteristics for each road segment within its jurisdiction. In 1985, the Federal Highway Administration (FHWA) published the Traffic Monitoring Guide to assist states in achieving this end. As with almost any data collection effort, the monitoring data suffers from errors from many sources. In this paper, we report some empirical findings in a research project sponsored by the FHWA. This research project studied the variability in the traffic data from the continuously monitored road segments from state(s) and, the extent to which this variability is transferred to and affects the precision of the data produced from the road segments which are monitored only one or two days each year. The ultimate hope is that states will eventually be able to not only publish an estimate of a characteristic such as Average Annual Daily Traffic (AADT) for each road segment, but also that each estimate will be accompanied by a statement expressing how good the estimate is in terms of its estimated variability or precision, which will likely be expressed as a coefficient of variation.

  5. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  6. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  7. Long-Term Wind Power Variability

    SciTech Connect (OSTI)

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  8. Crystal diffraction lens with variable focal length

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    1991-01-01

    A method and apparatus for altering the focal length of a focusing element o one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels.

  9. Crystal diffraction lens with variable focal length

    DOE Patents [OSTI]

    Smither, R.K.

    1991-04-02

    A method and apparatus for altering the focal length of a focusing element of one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities is disclosed. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels. 19 figures.

  10. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  11. Reduction in Energy Consumption & Variability in Steel Foundry Operations

    SciTech Connect (OSTI)

    Frank Peters

    2005-05-04

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to large process variation. This indicates the need for ongoing monitoring of the process and system to quantify the effort being expended. A system to measure the grinding effort was investigated but did not prove to be successful. A weld wire counting system was shown to be very successful in tracking casting quality by monitoring the quantity of weld wire being expended on a per casting basis. Further use of such systems is highly recommended. The field studies showed that the visual inspection process for the casting surface was a potentially large source of process variation. Measurement system analysis studies were conducted at three steel casting producers. The tests measured the consistency of the inspectors in identifying the same surface anomalies. The repeatability (variation of the same operator inspecting the same casting) was found to be relatively consistent across the companies at about 60-70%. However, this is still are very large amount of variation. Reproducibility (variation of different operators inspecting the same casting) was worse, ranging between 20 to 80% at the three locations. This large amount of variation shows that there is a great opportunity for improvement. Falsely identifying anomalies for reworking will cause increased expense and energy consumption. This is particularly true if a weld repair and repeated heat treatment is required. However, not identifying an anomaly could also result in future rework processing, a customer return, or scrap. To help alleviate this problem, casting surface comparator plates were developed and distributed to the industry. These plates are very inexpensive which enables them to be provided to all those involved with casting surface quality, such as operators, inspectors, sales, and management.

  12. Assessment of Normal Variability in Peripheral Blood Gene Expression

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Campbell, Catherine; Vernon, Suzanne D.; Karem, Kevin L.; Nisenbaum, Rosane; Unger, Elizabeth R.

    2002-01-01

    Peripheral blood is representative of many systemic processes and is an ideal sample for expression profiling of diseases that have no known or accessible lesion. Peripheral blood is a complex mixture of cell types and some differences in peripheral blood gene expression may reflect the timing of sample collection rather than an underlying disease process. For this reason, it is important to assess study design factors that may cause variability in gene expression not related to what is being analyzed. Variation in the gene expression of circulating peripheral blood mononuclear cells (PBMCs) from three healthy volunteers sampled three times onemore » day each week for one month was examined for 1,176 genes printed on filter arrays. Less than 1% of the genes showed any variation in expression that was related to the time of collection, and none of the changes were noted in more than one individual. These results suggest that observed variation was due to experimental variability.« less

  13. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, E.

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility. 14 figs.

  14. Variable Speed Wind Turbine Generator with Zero-sequence Filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  15. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-01-01

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  16. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, Thomas F. (Denver, CO)

    1998-01-01

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  17. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, T.F.

    1998-09-29

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  18. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, R.J.; Bible, D.W.; Paulauskas, F.L.

    1998-02-24

    A method for curing polymers incorporating a variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity is disclosed. By varying the frequency of the microwave signal, non-uniformities within the cavity are minimized, thereby achieving a more uniform cure throughout the workpiece. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. The furnace cavity may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing. 15 figs.

  19. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Paulauskas, Felix L. (Oak Ridge, TN)

    1998-01-01

    A method for curing polymers (11) incorporating a variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34). By varying the frequency of the microwave signal, non-uniformities within the cavity (34) are minimized, thereby achieving a more uniform cure throughout the workpiece (36). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. The furnace cavity (34) may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing.

  20. The RR Lyrae variable population in the Phoenix dwarf galaxy

    SciTech Connect (OSTI)

    Ordoez, Antonio J.; Sarajedini, Ata [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Yang, Soung-Chul, E-mail: a.ordonez@ufl.edu, E-mail: ata@astro.ufl.edu, E-mail: sczoo@kasi.re.kr [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of)

    2014-05-10

    We present the first detailed study of the RR Lyrae variable population in the Local Group dSph/dIrr transition galaxy, Phoenix, using previously obtained HST/WFPC2 observations of the galaxy. We utilize template light curve fitting routines to obtain best fit light curves for RR Lyrae variables in Phoenix. Our technique has identified 78 highly probable RR Lyrae stars (54 ab-type; 24 c-type) with about 40 additional candidates. We find mean periods for the two populations of (P {sub ab}) = 0.60 0.03 days and (P{sub c} ) = 0.353 0.002 days. We use the properties of these light curves to extract, among other things, a metallicity distribution function for ab-type RR Lyrae. Our analysis yields a mean metallicity of ([Fe/H]) = 1.68 0.06 dex for the RRab stars. From the mean period and metallicity calculated from the ab-type RR Lyrae, we conclude that Phoenix is more likely of intermediate Oosterhoff type; however the morphology of the Bailey diagram for Phoenix RR Lyraes appears similar to that of an Oosterhoff type I system. Using the RRab stars, we also study the chemical enrichment law for Phoenix. We find that our metallicity distribution is reasonably well fitted by a closed-box model. The parameters of this model are compatible with the findings of Hidalgo et al., further supporting the idea that Phoenix appears to have been chemically enriched as a closed-box-like system during the early stage of its formation and evolution.

  1. Role of Smarter Grids in Variable Renewable Resource Integration (Presentation)

    SciTech Connect (OSTI)

    Miller, M.

    2012-07-01

    This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.

  2. NERC Presentation: Accommodating High Levels of Variable Generation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight, waves, tidal forces, and some types of rivers) to ...

  3. ELVIRA. Evaluation of Longitudinal Variabler in Relativistic Accelerators

    SciTech Connect (OSTI)

    Larson, D.J.

    1993-06-07

    ELVIRA is an encoding of an analytical formula to the calculation of longitudinal dynamics variable evolution during an accelerator ramp.

  4. Variable Speed Pumping: A Guide to Successful Applications; Executive Summary

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    VARIABLE SPEED DRIVES A WAY TO LOWER LIFE CYCLE COSTS A GUIDE TO SUCCESSFUL APPLICATIONS A GUIDE TO SUCCESSFUL APPLICATIONS VARIABLE SPEED PUMPING VARIABLE SPEED PUMPING EXECUTIVE SUMMARY U.S. Department of Energy Energy Efficiency and Renewable Energy Industrial Technologies Program uropump VARIABLE SPEED DRIVES A WAY TO LOWER LIFE CYCLE COSTS Bringing you a prosperous future where energy is clean, abundant, reliable, and affordable Table of Contents Introduction . . . . . . . . . . . . . . . .

  5. NERC Presentation: Accommodating High Levels of Variable Generation,

    Office of Environmental Management (EM)

    October 29, 2010 | Department of Energy NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 North American Electric Reliability Corporation (NERC) presentation to the Electricity Advisory Committee, October 29, 2010, on accommodating high levels of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled,

  6. On the spatial decorrelation of stochastic solar resource variability at long timescales

    SciTech Connect (OSTI)

    Perez, Marc J. R.; Fthenakis, Vasilis M.

    2015-05-16

    Understanding the spatial and temporal characteristics of solar resource variability is important because it helps inform the discussion surrounding the merits of geographic dispersion and subsequent electrical interconnection of photovoltaics as part of a portfolio of future solutions for coping with this variability. The unpredictable resource variability arising from the stochastic nature of meteorological phenomena (from the passage of clouds to the movement of weather systems) is of most concern for achieving high PV penetration because unlike the passage of seasons or the shift from day to night, the uncertainty makes planning a challenge. A suitable proxy for unpredictable solar resource variability at any given location is the series of variations in the clearness index from one time period to the next because the clearness index is largely independent of the predictable influence of solar geometry. At timescales shorter than one day, the correlation between these variations in clearness index at pairs of distinct geographic locations decreases with spatial extent and with timescale. As the aggregate variability across N decorrelated locations decreases as 1/√N, identifying the distance required to achieve this decorrelation is critical to quantifying the expected reduction in variability from geographic dispersion.

  7. On the spatial decorrelation of stochastic solar resource variability at long timescales

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Perez, Marc J. R.; Fthenakis, Vasilis M.

    2015-05-16

    Understanding the spatial and temporal characteristics of solar resource variability is important because it helps inform the discussion surrounding the merits of geographic dispersion and subsequent electrical interconnection of photovoltaics as part of a portfolio of future solutions for coping with this variability. The unpredictable resource variability arising from the stochastic nature of meteorological phenomena (from the passage of clouds to the movement of weather systems) is of most concern for achieving high PV penetration because unlike the passage of seasons or the shift from day to night, the uncertainty makes planning a challenge. A suitable proxy for unpredictable solarmore » resource variability at any given location is the series of variations in the clearness index from one time period to the next because the clearness index is largely independent of the predictable influence of solar geometry. At timescales shorter than one day, the correlation between these variations in clearness index at pairs of distinct geographic locations decreases with spatial extent and with timescale. As the aggregate variability across N decorrelated locations decreases as 1/√N, identifying the distance required to achieve this decorrelation is critical to quantifying the expected reduction in variability from geographic dispersion.« less

  8. Variable effect desorber-resorber absorption cycle

    DOE Patents [OSTI]

    Biermann, Wendell J. (Fayetteville, NY)

    1985-01-01

    An absorption refrigeration system has an intermediate temperature desorber-resorber pair. A valve between the desorber-resorber pair is modulated to control the capacity for load matching.

  9. Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience

    SciTech Connect (OSTI)

    Cochran, J.; Bird, L.; Heeter, J.; Arent, D. A.

    2012-04-01

    Many countries -- reflecting very different geographies, markets, and power systems -- are successfully managing high levels of variable renewable energy on the electric grid, including that from wind and solar energy. This study documents the diverse approaches to effective integration of variable renewable energy among six countries -- Australia (South Australia), Denmark, Germany, Ireland, Spain, and the United States (Western region-Colorado and Texas)-- and summarizes policy best practices that energy ministers and other stakeholders can pursue to ensure that electricity markets and power systems can effectively coevolve with increasing penetrations of variable renewable energy. Each country has crafted its own combination of policies, market designs, and system operations to achieve the system reliability and flexibility needed to successfully integrate renewables. Notwithstanding this diversity, the approaches taken by the countries studied all coalesce around five strategic areas: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations. The ability to maintain a broad ecosystem perspective, to organize and make available the wealth of experiences, and to ensure a clear path from analysis to enactment should be the primary focus going forward.

  10. Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities

    DOE Patents [OSTI]

    Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)

    1997-01-01

    An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.

  11. Vegetation regulation on streamflow intra-annual variability through adaption to climate variations

    SciTech Connect (OSTI)

    Ye, Sheng; Li, Hongyi; Li, Shuai; Leung, Lai-Yung R.; Demissie, Yonas; Ran, Qihua; Blschl, Gnter

    2015-12-16

    This study aims to provide a mechanistic explanation of the empirical patterns of streamflow intra-annual variability revealed by watershed-scale hydrological data across the contiguous United States. A mathematical extension of the Budyko formula with explicit account for the soil moisture storage change is used to show that, in catchments with a strong seasonal coupling between precipitation and potential evaporation, climate aridity has a dominant control on intra-annual streamflow variability, but in other catchments, additional factors related to soil water storage change also have important controls on how precipitation seasonality propagates to streamflow. More importantly, use of leaf area index as a direct and indirect indicator of the above ground biomass and plant root system, respectively, reveals the vital role of vegetation in regulating soil moisture storage and hence streamflow intra-annual variability under different climate conditions.

  12. Indian Monsoon Depression: Climatology and Variability

    SciTech Connect (OSTI)

    Yoon, Jin-Ho; Huang, Wan-Ru

    2012-03-09

    The monsoon climate is traditionally characterized by large seasonal rainfall and reversal of wind direction (e.g., Krishnamurti 1979). Most importantly this rainfall is the major source of fresh water to various human activities such as agriculture. The Indian subcontinent resides at the core of the Southeast Asian summer monsoon system, with the monsoon trough extended from northern India across Indochina to the Western Tropical Pacific (WTP). Large fraction of annual rainfall occurs during the summer monsoon season, i.e., June - August with two distinct maxima. One is located over the Bay of Bengal with rainfall extending northwestward into eastern and central India, and the other along the west coast of India where the lower level moist wind meets the Western Ghat Mountains (Saha and Bavardeckar 1976). The rest of the Indian subcontinent receives relatively less rainfall. Various weather systems such as tropical cyclones and weak disturbances contribute to monsoon rainfall (Ramage 1971). Among these systems, the most efficient rain-producing system is known as the Indian monsoon depression (hereafter MD). This MD is critical for monsoon rainfall because: (i) it occurs about six times during each summer monsoon season, (ii) it propagates deeply into the continent and produces large amounts of rainfall along its track, and (iii) about half of the monsoon rainfall is contributed to by the MDs (e.g., Krishnamurti 1979). Therefore, understanding various properties of the MD is a key towards comprehending the veracity of the Indian summer monsoon and especially its hydrological process.

  13. Impact of Variable Valve Timing on Low Temperature Combustion | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Variable Valve Timing on Low Temperature Combustion Impact of Variable Valve Timing on Low Temperature Combustion Documents effects of variable valve actuation in implementing low temperature combustion in production engine platform. PDF icon deer10_de_ojeda.pdf More Documents & Publications Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Multicylinder Diesel Engine for Low

  14. Evaluation of Variable Compression Ratio on Energy Efficiency | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Variable Compression Ratio on Energy Efficiency Evaluation of Variable Compression Ratio on Energy Efficiency Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon p-16_szybist.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2015: High Efficiency VCR Engine with Variable Valve Actuation and New Supercharging Technology The Effects of Fuel Composition and

  15. Enabling High Efficiency Clean Combustion with Micro-Variable

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI | Department of Energy Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Enabling High Efficiency Clean Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Key characteristics of variable orifice fuel injector are described that will extend the operation maps of early PCCI combustion and enable dual-mode combustion over full operating maps. PDF icon deer08_hou.pdf

  16. Simulation of the intraseasonal variability over the Eastern Pacific ITCZ

    Office of Scientific and Technical Information (OSTI)

    in climate models (Journal Article) | SciTech Connect Simulation of the intraseasonal variability over the Eastern Pacific ITCZ in climate models Citation Details In-Document Search Title: Simulation of the intraseasonal variability over the Eastern Pacific ITCZ in climate models During boreal summer, convective activity over the eastern Pacific (EPAC) inter-tropical convergence zone (ITCZ) exhibits vigorous intraseasonal variability (ISV). Previous observational studies identified two

  17. A Variational Pro jection Operator for Mapping of Internal Variables...

    Office of Scientific and Technical Information (OSTI)

    Title: A Variational Pro jection Operator for Mapping of Internal Variables. Authors: Mota, Alejandro ; Sun, WaiChing ; Ostien, Jakob ; Foulk, James W., III ; Long, Kevin...

  18. Advanced Variable Speed Air-Source Integrated Heat Pump 2013...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program ...

  19. Host Lipid and Temperature as Important Screening Variables for...

    Office of Scientific and Technical Information (OSTI)

    Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral ... Citation Details In-Document Search Title: Host Lipid and Temperature as Important ...

  20. QUASAR OPTICAL VARIABILITY IN THE PALOMAR-QUEST SURVEY (Journal...

    Office of Scientific and Technical Information (OSTI)

    amplitude and optical luminosity, and measure the logarithmic decrease in variability amplitude to scale as the logarithm of the luminosity times 0.205 +- 0.002. Black ...

  1. Process for applying control variables having fractal structures

    DOE Patents [OSTI]

    Bullock, J.S. IV; Lawson, R.L.

    1996-01-23

    A process and apparatus are disclosed for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform. 3 figs.

  2. Adaptation to Climate Variability and Change: A Guidance Manual...

    Open Energy Info (EERE)

    Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Adaptation to Climate...

  3. Process for applying control variables having fractal structures

    DOE Patents [OSTI]

    Bullock, IV, Jonathan S. (Oak Ridge, TN); Lawson, Roger L. (Oliver Springs, TN)

    1996-01-01

    A process and apparatus for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform.

  4. First-Principles Investigation of Nanopore Sequencing Using Variable...

    Office of Scientific and Technical Information (OSTI)

    First-Principles Investigation of Nanopore Sequencing Using Variable Voltage Bias on Graphene-Based Nanoribbons Citation Details In-Document Search Title: First-Principles...

  5. Sub-daily Statistical Downscaling of Meteorological Variables...

    Office of Scientific and Technical Information (OSTI)

    and variance that was accurate within 1% for all variables except atmospheric pressure, wind speed, and precipitation. Correlations between downscaled output and the expected...

  6. Energy storage connection system

    DOE Patents [OSTI]

    Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

    2012-07-03

    A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

  7. Statistical Characterization of Solar Photovoltaic Power Variability at Small Timescales: Preprint

    SciTech Connect (OSTI)

    Shedd, S.; Hodge, B.-M.; Florita, A.; Orwig, K.

    2012-08-01

    Integrating large amounts of variable and uncertain solar photovoltaic power into the electricity grid is a growing concern for power system operators in a number of different regions. Power system operators typically accommodate variability, whether from load, wind, or solar, by carrying reserves that can quickly change their output to match the changes in the solar resource. At timescales in the seconds-to-minutes range, this is known as regulation reserve. Previous studies have shown that increasing the geographic diversity of solar resources can reduce the short term-variability of the power output. As the price of solar has decreased, the emergence of very large PV plants (greater than 10 MW) has become more common. These plants present an interesting case because they are large enough to exhibit some spatial smoothing by themselves. This work examines the variability of solar PV output among different arrays in a large ({approx}50 MW) PV plant in the western United States, including the correlation in power output changes between different arrays, as well as the aggregated plant output, at timescales ranging from one second to five minutes.

  8. Energy Systems Integration

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Systems Integration Ben Kroposki, PhD, PE Director, Energy Systems Integration National Renewable Energy Laboratory 2 Reducing investment risk and optimizing systems in a rapidly changing energy world * Increasing penetration of variable RE in grid * Increasing ultra high energy efficiency buildings and controllable loads * New data, information, communications and controls * Electrification of transportation and alternative fuels * Integrating energy storage (stationary and mobile) and thermal

  9. Impacts of Variability and Uncertainty in Solar Photovoltaic Generation at Multiple Timescales

    SciTech Connect (OSTI)

    Ela, E.; Diakov, V.; Ibanez, E.; Heaney, M.

    2013-05-01

    The characteristics of variability and uncertainty of PV solar power have been studied extensively. These characteristics can create challenges for system operators who must ensure a balance between generation and demand while obeying power system constraints at the lowest possible cost. A number of studies have looked at the impact of wind power plants, and some recent studies have also included solar PV. The simulations that are used in these studies, however, are typically fixed to one time resolution. This makes it difficult to analyze the variability across several timescales. In this study, we use a simulation tool that has the ability to evaluate both the economic and reliability impacts of PV variability and uncertainty at multiple timescales. This information should help system operators better prepare for increases of PV on their systems and develop improved mitigation strategies to better integrate PV with enhanced reliability. Another goal of this study is to understand how different mitigation strategies and methods can improve the integration of solar power more reliably and efficiently.

  10. Feasibility of wavelet expansion methods to treat the energy variable

    SciTech Connect (OSTI)

    Van Rooijen, W. F. G.

    2012-07-01

    This paper discusses the use of the Discrete Wavelet Transform (DWT) to implement a functional expansion of the energy variable in neutron transport. The motivation of the work is to investigate the possibility of adapting the expansion level of the neutron flux in a material region to the complexity of the cross section in that region. If such an adaptive treatment is possible, 'simple' material regions (e.g., moderator regions) require little effort, while a detailed treatment is used for 'complex' regions (e.g., fuel regions). Our investigations show that in fact adaptivity cannot be achieved. The most fundamental reason is that in a multi-region system, the energy dependence of the cross section in a material region does not imply that the neutron flux in that region has a similar energy dependence. If it is chosen to sacrifice adaptivity, then the DWT method can be very accurate, but the complexity of such a method is higher than that of an equivalent hyper-fine group calculation. The conclusion is thus that, unfortunately, the DWT approach is not very practical. (authors)

  11. Nova-like cataclysmic variables in the infrared

    SciTech Connect (OSTI)

    Hoard, D. W.; Long, Knox S.; Howell, Steve B.; Wachter, Stefanie; Brinkworth, Carolyn S.; Knigge, Christian; Drew, J. E.; Szkody, Paula; Kafka, S.; Belle, Kunegunda; Ciardi, David R.; Froning, Cynthia S.; Van Belle, Gerard T.; Pretorius, M. L.

    2014-05-01

    Nova-like (NL) cataclysmic variables have persistently high mass transfer rates and prominent steady state accretion disks. We present an analysis of infrared observations of 12 NLs obtained from the Two Micron All Sky Survey, the Spitzer Space Telescope, and the Wide-field Infrared Survey Explorer All Sky Survey. The presence of an infrared excess at ? ? 3-5 ?m over the expectation of a theoretical steady state accretion disk is ubiquitous in our sample. The strength of the infrared excess is not correlated with orbital period, but shows a statistically significant correlation (but shallow trend) with system inclination that might be partially (but not completely) linked to the increasing view of the cooler outer accretion disk and disk rim at higher inclinations. We discuss the possible origin of the infrared excess in terms of emission from bremsstrahlung or circumbinary dust, with either mechanism facilitated by the mass outflows (e.g., disk wind/corona, accretion stream overflow, and so on) present in NLs. Our comparison of the relative advantages and disadvantages of either mechanism for explaining the observations suggests that the situation is rather ambiguous, largely circumstantial, and in need of stricter observational constraints.

  12. Variable current speed controller for eddy current motors

    DOE Patents [OSTI]

    Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

    1982-03-12

    A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

  13. Integrating Variable Renewable Energy in Electric Power Markets. Best Practices from International Experience, Summary for Policymakers

    SciTech Connect (OSTI)

    Cochran, Jaquelin; Bird, Lori; Heeter, Jenny; Arent, Douglas J.

    2012-04-30

    Many countries - reflecting very different geographies, markets, and power systems - are successfully managing high levels of variable renewable energy on the electric grid, including that from wind and solar energy. This document summarizes policy best practices that energy ministers and other stakeholders can pursue to ensure that electricity markets and power systems can effectively coevolve with increasing penetrations of variable renewable energy. There is no one-size-fits-all approach; each country studied has crafted its own combination of policies, market designs, and system operations to achieve the system reliability and flexibility needed to successfully integrate renewables. Notwithstanding this diversity, the approaches taken by the countries studied all coalesce around five strategic areas: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations. This study also emphatically underscores the value of countries sharing their experiences. The more diverse and robust the experience base from which a country can draw, the more likely that it will be able to implement an appropriate, optimized, and system-wide approach.

  14. Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience, Summary for Policymakers

    SciTech Connect (OSTI)

    Cochran, J.; Bird, L.; Heeter, J.; Arent, D. A.

    2012-04-01

    Many countries -- reflecting very different geographies, markets, and power systems -- are successfully managing high levels of variable renewable energy on the electric grid, including that from wind and solar energy. This document summarizes policy best practices that energy ministers and other stakeholders can pursue to ensure that electricity markets and power systems can effectively coevolve with increasing penetrations of variable renewable energy. There is no one-size-fits-all approach; each country studied has crafted its own combination of policies, market designs, and system operations to achieve the system reliability and flexibility needed to successfully integrate renewables. Notwithstanding this diversity, the approaches taken by the countries studied all coalesce around five strategic areas: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations. This study also emphatically underscores the value of countries sharing their experiences. The more diverse and robust the experience base from which a country can draw, the more likely that it will be able to implement an appropriate, optimized, and system-wide approach.

  15. Promising Technology: Magnetic Bearing Variable-Speed Centrifugal Chillers

    Broader source: Energy.gov [DOE]

    Magnetic bearing variable speed centrifugal chillers save energy compared to conventional chillers by eliminating friction with the magnetic bearings and by improving efficiency at partial loads with the variable speed drive. In addition to saving energy, the magnetic bearings eliminate the maintenance costs associated with lubricating conventional metal bearings.

  16. Analysis of Cloud Variability and Sampling Errors in Surface and Satellite Mesurements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Analysis of Cloud Variability and Sampling Errors in Surface and Satellite Measurements Z. Li, M. C. Cribb, and F.-L. Chang Earth System Science Interdisciplinary Center University of Maryland College Park, Maryland A. P. Trishchenko and Y. Luo Canada Centre for Remote Sensing Ottawa, Ontario, Canada Introduction Radiation measurements have been widely employed for evaluating cloud parameterization schemes and model simulation results. As the most comprehensive program aiming to improve cloud

  17. Modeling Solar Power Plant Variability: Benefits of Geographic Smoothing at Various Timescales

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    position with even amount of white space between photos and header Ota City: Characterizing Output Variability from 553 Homes with Residential PV Systems Matthew Lave U.S.-Japan Collaborative Smart Grid Project Collective Research Workshop Dec. 5, 2013 SAND2013-10076 1 Overview  Pal Town neighborhood in Ota City, Japan a unique test bed of high-penetration distributed PV  NEDO installed PV on ~80% of rooftops in neighborhood  Data collected every 1-second  Sandia conducted analysis

  18. Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study

    SciTech Connect (OSTI)

    Cappers, Peter; Mills, Andrew; Goldman, Charles; Wiser, Ryan; Eto, Joseph H.

    2011-09-10

    This scoping study focuses on the policy issues inherent in the claims made by some Smart Grid proponents that the demand response potential of mass market customers which is enabled by widespread implementation of Advanced Metering Infrastructure (AMI) through the Smart Grid could be the silver bullet for mitigating variable generation integration issues. In terms of approach, we will: identify key issues associated with integrating large amounts of variable generation into the bulk power system; identify demand response opportunities made more readily available to mass market customers through widespread deployment of AMI systems and how they can affect the bulk power system; assess the extent to which these mass market Demand Response (DR) opportunities can mitigate Variable Generation (VG) integration issues in the near-term and what electricity market structures and regulatory practices could be changed to further expand the ability for DR to mitigate VG integration issues over the long term; and provide a qualitative comparison of DR and other approaches to mitigate VG integration issues.

  19. Integrating Variable Renewable Energy in Electric Power Markets. Best Practices from International Experience

    SciTech Connect (OSTI)

    Cochran, Jaquelin; Bird, Lori; Heeter, Jenny; Arent, Douglas J.

    2012-04-30

    Many countries—reflecting very different geographies, markets, and power systems—are successfully managing high levels of variable renewable energy on the electric grid, including that from wind and solar energy. This document summarizes policy best practices that energy ministers and other stakeholders can pursue to ensure that electricity markets and power systems can effectively coevolve with increasing penetrations of variable renewable energy. There is no one-size-fits-all approach; each country studied has crafted its own combination of policies, market designs, and system operations to achieve the system reliability and flexibility needed to successfully integrate renewables. Notwithstanding this diversity, the approaches taken by the countries studied all coalesce around five strategic areas: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations. This study also emphatically underscores the value of countries sharing their experiences. The more diverse and robust the experience base from which a country can draw, the more likely that it will be able to implement an appropriate, optimized, and system-wide approach.

  20. Cooling and Heating Season Impacts of Right-Sizing of Fixed- and Variable-Capacity Heat Pumps With Attic and Indoor Ductwork

    SciTech Connect (OSTI)

    Cummings, James; Withers, Charles; Kono, Jamie

    2015-06-01

    ?A new generation of central, ducted variable-capacity heat pump systems has come on the market, promising very high cooling and heating efficiency. They are controlled differently than standard fixed-capacity systems. Instead of cycling on at full capacity and then cycling off when the thermostat is satisfied, they vary their cooling and heating output over a wide range (approximately 40% - 118% of nominal full capacity), thus staying 'on' for 60% - 100% more hours per day compared to fixed -capacity systems. Experiments in this research examined the performance of 2-ton and 3-ton fixed- and variable-capacity systems and the impacts of system oversizing.

  1. Solar Reserve Methodology for Renewable Energy Integration Studies Based on Sub-Hourly Variability Analysis: Preprint

    SciTech Connect (OSTI)

    Ibanez, E.; Brinkman, G.; Hummon, M.; Lew, D.

    2012-08-01

    Increasing penetrations of wind a solar energy are raising concerns among electric system operators because of the variability and uncertainty associated with power sources. Previous work focused on the quantification of reserves for systems with wind power. This paper presents a new methodology that allows the determination of necessary reserves for high penetrations of photovoltaic (PV) power and compares it to the wind-based methodology. The solar reserve methodology is applied to Phase 2 of the Western Wind and Solar Integration Study. A summary of the results is included.

  2. SPECTROSCOPY OF NEW AND POORLY KNOWN CATACLYSMIC VARIABLES IN THE KEPLER FIELD

    SciTech Connect (OSTI)

    Howell, Steve B.; Still, Martin; Everett, Mark E.; Seebode, Sally A.; Szkody, Paula; Wood, Matt; Ramsay, Gavin; Cannizzo, John

    2013-04-15

    The NASA Kepler mission has been in science operation since 2009 May and is providing high precision, high cadence light curves of over 150,000 targets. Prior to launch, nine cataclysmic variables were known to lie within Kepler's field of view. We present spectroscopy for seven systems, four of which were newly discovered since launch. All of the stars presented herein have been observed by, or are currently being observed by, the Kepler space telescope. Three historic systems and one new candidate could not be detected at their sky position and two candidates are called into question as to their true identity.

  3. [A variable frequency microwave furnace]. CRADA final report for CRADA Number ORNL91-0055

    SciTech Connect (OSTI)

    Lauf, R.J.

    1994-12-08

    The goals of this CRADA were to: (1) development and demonstrate a highly frequency-agile microwave furnace; (2) explore applications of the furnace for materials processing; and (3) develop control systems and packaging that are robust, user-friendly, and suitable for sale as a turnkey system. Microwave Laboratories, Inc. (MLI) designed, built, and successfully brought to market a benchtop Variable Frequency Microwave Furnace (VFMF). The concept has demonstrated advantages in polymer curing, waste remediation, and diamond (CVD). Through experimentation and modeling, the VFMF approach has gained credibility within the technical community.

  4. Active optical zoom system

    DOE Patents [OSTI]

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  5. Variable speed pumping: A guide to successful applications - Executive summary

    SciTech Connect (OSTI)

    None, None

    2004-05-01

    This document is the result of a collaboration between the Hydraulic Institute, Europump, and the U.S. DOE Industrial Technologies Program, and describes the cost and energy savings potential of pumping applications with variable duty requirements.

  6. USING CLOUD CLASSIFICATION TO MODEL SOLAR VARIABILITY Matthew...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and variability profile for the location. 11. REFERENCES 1 R. J. Broderick, J. E. Quiroz, M. J. Reno, A. Ellis, J. Smith, and R. Dugan, "Time Series Power Flow Analysis for...

  7. Study finds surprising variability in shape of Van Allen Belts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Study finds surprising variability in shape of Van Allen Belts Study finds surprising variability in shape of Van Allen Belts Understanding the shape and size of the belts, which shrink and swell in response to magnetic storms coming from the sun, is crucial for protecting our technology in space. February 23, 2016 1. The traditional idea of the radiation belts includes a larger, more dynamic outer belt and a smaller, more stable inner belt with an empty slot region separating the two. However,

  8. Host Lipid and Temperature as Important Screening Variables for

    Office of Scientific and Technical Information (OSTI)

    Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol Kinase (Journal Article) | SciTech Connect Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol Kinase Citation Details In-Document Search Title: Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol

  9. Envera Variable Compression Ratio Engine (Technical Report) | SciTech

    Office of Scientific and Technical Information (OSTI)

    Connect Envera Variable Compression Ratio Engine Citation Details In-Document Search Title: Envera Variable Compression Ratio Engine × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. A paper copy of this document is also available for sale to the

  10. Comparison of Parameterized Cloud Variability to ARM Data

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Comparison of Parameterized Cloud Variability to ARM Data S. A. Klein National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Laboratory Princeton, New Jersey J. R. Norris Scripps Institute of Oceanography University of California La Jolla, California Abstract Cloud parameterizations in large-scale models often try to predict the amount of sub-grid scale variability in cloud properties to address the significant non-linear effects of radiation and precipitation. Statistical

  11. Continuously variable transmissions: theory and practice (Technical Report)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | SciTech Connect Continuously variable transmissions: theory and practice Citation Details In-Document Search Title: Continuously variable transmissions: theory and practice × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. A paper copy of this

  12. Variable Renewable Energy: a Regulatory Roadmap (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-10-01

    There is not a one-size-fits-all approach to the regulation of variable renewable energy (VRE), but international experience reveals many approaches that are proving successful. Drawing upon research and experiences from various international contexts, the 21st Century Power Partnership in conjunction with the Clean Energy Solutions Center and Clean Energy Regulators Initiative identified key issues and ideas that have emerged as variable deployment has grown. The Power Partnership research, published in 2014, identified four broad categories of regulatory issues.

  13. Variable Voltage Substation Electric Fire and Emergency Response |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Variable Voltage Substation Electric Fire and Emergency Response Variable Voltage Substation Electric Fire and Emergency Response Question from Participant: My question is from an emergency response perspective. It was stated that it took ~ ½ for electricians to de-energize the electrical components before firefighters were allowed in to fight the fire. This delay causes more damage to equipment and potential propagation of the fire. Is there not a "master"

  14. Self-Referenced Continuous-Variable Quantum Key Distribution Protocol

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Citation Details In-Document Search Title: Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Authors: Soh, Daniel B. S. ; Brif, Constantin ; Coles, Patrick J. ; Lütkenhaus, Norbert ; Camacho, Ryan M. ; Urayama, Junji ; Sarovar, Mohan Publication Date: 2015-10-21 OSTI Identifier: 1224143 Grant/Contract Number: AC04-94AL85000 Type: Published Article Journal Name:

  15. Bottling Electricity: Storage as a Strategic Tool for Managing Variability

    Energy Savers [EERE]

    and Capacity Concerns in the Modern Grid - EAC Report (December 2008) | Department of Energy Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) The objectives of this report are to provide the Secretary of Energy with the Electricity Advisory Committee's

  16. Hydrogen-Assisted Fracture: Materials Testing and Variables Governing

    Office of Environmental Management (EM)

    Fracture | Department of Energy Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture SNL has 40+ years experience with effects of high-pressure hydrogen gas on materials PDF icon hpwgw_matresearch_somerday.pdf More Documents & Publications Mechanical Properties of Structural Steels in Hydrogen Materials Compatibility Properties, Behavior and Material Compatibility of Hydrogen, Natural

  17. Load sensing system

    DOE Patents [OSTI]

    Sohns, Carl W. (Oak Ridge, TN); Nodine, Robert N. (Knoxville, TN); Wallace, Steven Allen (Knoxville, TN)

    1999-01-01

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast

  18. Equilibria in Chemical Systems

    Energy Science and Technology Software Center (OSTI)

    1992-01-01

    SOLGASMIX-PV calculates equilibrium relationships in complex chemical systems. Chemical equilibrium calculations involve finding the system composition, within certain constraints, which contains the minimum free energy. The constraints are the preservation of the masses of each element present and either constant pressure or volume. SOLGASMIX-PV can calculate equilibria in systems containing a gaseous phase, condensed phase solutions, and condensed phases of invariant and variable stoichiometry. Either a constant total gas volume or a constant total pressuremore » can be assumed. Unit activities for condensed phases and ideality for solutions are assumed, although nonideal systems can be handled provided activity coefficient relationships are available.« less

  19. Asymptotic behavior of dynamical variables and naked singularity formation in spherically symmetric gravitational collapse

    SciTech Connect (OSTI)

    Kawakami, Hayato; Mitsuda, Eiji; Nambu, Yasusada; Tomimatsu, Akira

    2009-07-15

    In considering the gravitational collapse of matter, it is an important problem to clarify what kind of conditions leads to the formation of naked singularity. For this purpose, we apply the 1+3 orthonormal frame formalism introduced by Uggla et al. to the spherically symmetric gravitational collapse of a perfect fluid. This formalism allows us to construct an autonomous system of evolution and constraint equations for scale-invariant dynamical variables normalized by the volume expansion rate of the timelike orthonormal frame vector. We investigate the asymptotic evolution of such dynamical variables towards the formation of a central singularity and present a conjecture that the steep spatial gradient for the normalized density function is a characteristic of the naked singularity formation.

  20. A monitoring campaign for Luhman 16AB. I. Detection of resolved near-infrared spectroscopic variability

    SciTech Connect (OSTI)

    Burgasser, Adam J.; Gillon, Michal; Jehin, E.; Delrez, L.; Opitom, C.; Faherty, Jacqueline K.; Radigan, Jacqueline; Triaud, Amaury H. M. J.; Plavchan, Peter

    2014-04-10

    We report resolved near-infrared spectroscopic monitoring of the nearby L dwarf/T dwarf binary WISE J104915.57531906.1AB (Luhman 16AB), as part of a broader campaign to characterize the spectral energy distribution and temporal variability of this system. A continuous 45 minute sequence of low-resolution IRTF/SpeX data spanning 0.8-2.4 ?m were obtained, concurrent with combined-light optical photometry with ESO/TRAPPIST. Our spectral observations confirm the flux reversal of this binary, and we detect a wavelength-dependent decline in the relative spectral fluxes of the two components coincident with a decline in the combined-light optical brightness of the system over the course of the observation. These data are successfully modeled as a combination of achromatic (brightness) and chromatic (color) variability in the T0.5 Luhman 16B, consistent with variations in overall cloud opacity; and no significant variability was found in L7.5 Luhman 16A, consistent with recent resolved photometric monitoring. We estimate a peak-to-peak amplitude of 13.5% at 1.25 ?m over the full light curve. Using a simple two-spot brightness temperature model for Luhman 16B, we infer an average cold covering fraction of ?30%-55%, varying by 15%-30% over a rotation period assuming a ?200-400 K difference between hot and cold regions. We interpret these variations as changes in the covering fraction of a high cloud deck and corresponding 'holes' which expose deeper, hotter cloud layers, although other physical interpretations are possible. A Rhines scale interpretation for the size of the variable features explains an apparent correlation between period and amplitude for Luhman 16B and the variable T dwarfs SIMP 0136+0933 and 2MASS J2139+0220, and predicts relatively fast winds (1-3 km s{sup 1}) for Luhman 16B consistent with light curve evolution on an advective time scale (1-3 rotation periods). The strong variability observed in this flux reversal brown dwarf pair supports the model of a patchy disruption of the mineral cloud layer as a universal feature of the L dwarf/T dwarf transition.

  1. Analysis of Variability and Uncertainty in Wind Power Forecasting: An International Comparison: Preprint

    SciTech Connect (OSTI)

    Zhang, J.; Hodge, B. M.; Gomez-Lazaro, E.; Lovholm, A. L.; Berge, E.; Miettinen, J.; Holttinen, H.; Cutululis, N.; Litong-Palima, M.; Sorensen, P.; Dobschinski, J.

    2013-10-01

    One of the critical challenges of wind power integration is the variable and uncertain nature of the resource. This paper investigates the variability and uncertainty in wind forecasting for multiple power systems in six countries. An extensive comparison of wind forecasting is performed among the six power systems by analyzing the following scenarios: (i) wind forecast errors throughout a year; (ii) forecast errors at a specific time of day throughout a year; (iii) forecast errors at peak and off-peak hours of a day; (iv) forecast errors in different seasons; (v) extreme forecasts with large overforecast or underforecast errors; and (vi) forecast errors when wind power generation is at different percentages of the total wind capacity. The kernel density estimation method is adopted to characterize the distribution of forecast errors. The results show that the level of uncertainty and the forecast error distribution vary among different power systems and scenarios. In addition, for most power systems, (i) there is a tendency to underforecast in winter; and (ii) the forecasts in winter generally have more uncertainty than the forecasts in summer.

  2. Superconducting fault current-limiter with variable shunt impedance

    DOE Patents [OSTI]

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  3. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-08-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  4. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-10-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  5. CBEI: AHU FDD in Small and Medium Sized Commercial Buildings - 2015 Peer

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Review | Department of Energy AHU FDD in Small and Medium Sized Commercial Buildings - 2015 Peer Review CBEI: AHU FDD in Small and Medium Sized Commercial Buildings - 2015 Peer Review Presenter: Jin Wen, Drexel View the Presentation PDF icon CBEI: AHU FDD in Small and Medium Sized Commercial Buildings - 2015 Peer Review More Documents & Publications Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant Air Volume

  6. Quantum simulation of quantum field theory using continuous variables

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Marshall, Kevin; Pooser, Raphael C.; Siopsis, George; Weedbrook, Christian

    2015-12-14

    Much progress has been made in the field of quantum computing using continuous variables over the last couple of years. This includes the generation of extremely large entangled cluster states (10,000 modes, in fact) as well as a fault tolerant architecture. This has lead to the point that continuous-variable quantum computing can indeed be thought of as a viable alternative for universal quantum computing. With that in mind, we present a new algorithm for continuous-variable quantum computers which gives an exponential speedup over the best known classical methods. Specifically, this relates to efficiently calculating the scattering amplitudes in scalar bosonicmore » quantum field theory, a problem that is known to be hard using a classical computer. Thus, we give an experimental implementation based on cluster states that is feasible with today's technology.« less

  7. Implementing the DC Mode in Cosmological Simulations with Supercomoving Variables

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gnedin, Nickolay Y; Kravtsov, Andrey V; Rudd, Douglas H

    2011-06-02

    As emphasized by previous studies, proper treatment of the density fluctuation on the fundamental scale of a cosmological simulation volume - the 'DC mode' - is critical for accurate modeling of spatial correlations on scales ~> 10% of simulation box size. We provide further illustration of the effects of the DC mode on the abundance of halos in small boxes and show that it is straightforward to incorporate this mode in cosmological codes that use the 'supercomoving' variables. The equations governing evolution of dark matter and baryons recast with these variables are particularly simple and include the expansion factor, andmorehence the effect of the DC mode, explicitly only in the Poisson equation.less

  8. Variable Charge Motion for 2007-2010 Heavy Duty Diesel Engines | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Charge Motion for 2007-2010 Heavy Duty Diesel Engines Variable Charge Motion for 2007-2010 Heavy Duty Diesel Engines 2003 DEER Conference Presentation: AVL Powertrain Engineering PDF icon 2003_deer_maier.pdf More Documents & Publications Lowest Engine-Out Emissions as the Key to the Future of the Heavy-Duty Diesel Engine: New Development Rersults Can Future Emissions Limits be Met with a Hybrid EGR System Alone? Sources of CO and UHC Emissions in Low-Temperature Diesel

  9. Method and apparatus for conducting variable thickness vapor deposition

    DOE Patents [OSTI]

    Nesslage, G.V.

    1984-08-03

    A method of vapor depositing metal on a substrate in variable thickness comprises conducting the deposition continuously without interruption to avoid formation of grain boundaries. To achieve reduced deposition in specific regions a thin wire or ribbon blocking body is placed between source and substrate to partially block vapors from depositing in the region immediately below.

  10. On computing ``accurate'' derivatives of Equation-of-State variables

    SciTech Connect (OSTI)

    Shestakov, A. I.

    2015-12-11

    We analyze a log-log interpolant for 2D EOS lookups, where the EOS independent variables are, say, T and ?. If the data f (Ti, ?j) are in the form of a power law, even locally, the interpolant is exact.

  11. Methodology for testing metal detectors using variables test data

    SciTech Connect (OSTI)

    Spencer, D.D.; Murray, D.W.

    1993-08-01

    By extracting and analyzing measurement (variables) data from portal metal detectors whenever possible instead of the more typical ``alarm``/``no-alarm`` (attributes or binomial) data, we can be more informed about metal detector health with fewer tests. This testing methodology discussed in this report is an alternative to the typical binomial testing and in many ways is far superior.

  12. THE CLASSIFICATION OF KEPLER B-STAR VARIABLES

    SciTech Connect (OSTI)

    McNamara, Bernard J.; Jackiewicz, Jason; McKeever, Jean E-mail: jasonj@nmsu.edu

    2012-04-15

    The light curves of 252 B-star candidates in the Kepler database are analyzed in a similar fashion to that done by Balona et al. to further characterize B-star variability, increase the sample of variable B stars for future study, and to identify stars whose power spectra include particularly interesting features such as frequency groupings. Stars are classified as either constant light emitters, {beta} Cep stars, slowly pulsating B stars (SPBs), hybrid pulsators, binaries or stars whose light curves are dominated by rotation (Bin/Rot), hot subdwarfs, or white dwarfs. One-hundred stars in our sample were found to be either light constants or to be variable at a level of less than 0.02 mmag. We increase the number of candidate B-star variables found in the Kepler database by Balona et al. in the following fashion: {beta} Cep stars from 0 to 10, SPBs from eight to 54, hybrid pulsators from seven to 21, and Bin/Rot stars from 23 to 82. For comparison purposes, approximately 51 SPBs and six hybrids had been known prior to 2007. The number of {beta} Cep stars known prior to 2004 was 93. A secondary result of this study is the identification of an additional 11 pulsating white dwarf candidates, four of which possess frequency groupings.

  13. Analysis Methodology for Balancing Authority Cooperation in High Penetration of Variable Generation

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Etingov, Pavel V.; Zhou, Ning; Ma, Jian; Samaan, Nader A.; Diao, Ruisheng; Malhara, Sunita V.; Guttromson, Ross T.; Du, Pengwei; Sastry, Chellury

    2010-02-01

    With the rapidly growing penetration level of wind and solar generation, the challenges of managing variability and the uncertainty of intermittent renewable generation become more and more significant. The problem of power variability and uncertainty gets exacerbated when each balancing authority (BA) works locally and separately to balance its own subsystem. The virtual BA concept means various forms of collaboration between individual BAs must manage power variability and uncertainty. The virtual BA will have a wide area control capability in managing its operational balancing requirements in different time frames. This coordination results in the improvement of efficiency and reliability of power system operation while facilitating the high level integration of green, intermittent energy resources. Several strategies for virtual BA implementation, such as ACE diversity interchange (ADI), wind only BA, BA consolidation, dynamic scheduling, regulation and load following sharing, extreme event impact study are discussed in this report. The objective of such strategies is to allow individual BAs within a large power grid to help each other deal with power variability. Innovative methods have been developed to simulate the balancing operation of BAs. These methods evaluate the BA operation through a number of metrics such as capacity, ramp rate, ramp duration, energy and cycling requirements to evaluate the performances of different virtual BA strategies. The report builds a systematic framework for evaluating BA consolidation and coordination. Results for case studies show that significant economic and reliability benefits can be gained. The merits and limitation of each virtual BA strategy are investigated. The report provides guidelines for the power industry to evaluate the coordination or consolidation method. The application of the developed strategies in cooperation with several regional BAs is in progress for several off-spring projects.

  14. Performance of Variable Capacity Heat Pumps in a Mixed Humid Climate

    SciTech Connect (OSTI)

    Munk, Jeffrey D; Gehl, Anthony C; Jackson, Roderick K

    2012-04-01

    Variable capacity heat pumps represent the next wave of technology for heat pumps. In this report, the performance of two variable capacity heat pumps (HPs) is compared to that of a single or two stage baseline system. The units were installed in two existing research houses located in Knoxville, TN. These houses were instrumented to collect energy use and temperature data while both the baseline systems and variable capacity systems were installed. The homes had computer controlled simulated occupancy, which provided consistent schedules for hot water use and lighting. The temperature control and energy use of the systems were compared during both the heating and cooling seasons. Multiple linear regression models were used along with TMY3 data for Knoxville, TN in order to normalize the effect that the outdoor air temperature has on energy use. This enables a prediction of each system's energy use over a year with the same weather. The first system was a multi-split system consisting of 8 indoor units and a single outdoor unit. This system replaced a 16 SEER single stage HP with a zoning system, which served as the baseline. Data was collected on the baseline system from August 2009 to December 2010 and on the multi-split system from January 2011 to January 2012. Soon after the installation of the multi-split system, some of the smaller rooms began over-conditioning. This was determined to be caused by a small amount of continuous refrigerant flow to all of the indoor units when the outdoor unit was running regardless of whether they were calling for heat. This, coupled with the fact that the indoor fans run continuously, was providing enough heat in some rooms to exceed the set point. In order to address this, the indoor fans were disabled when not actively heating per the manufacturer's recommendation. Based on the measured data, the multi-split system was predicted to use 40% more energy in the heating season and 16% more energy in the cooling season than the baseline system, for the typical meteorological year weather data. The AHRI ratings indicated that the baseline system would perform slightly better than the multi-split system, but not by as large of a margin as seen in this study. The multi-split system was able to maintain more consistent temperature throughout the house than the baseline system, but it did allow relative humidity levels to increase above 60% in the summer. The second system was a split system with an inverter driven compressor and a single ducted air handler. This unit replaced a 16 SEER two stage HP with a zoning system. Data was collected on the baseline system from July 2009 to November 2010 and on the ducted inverter system from December 2010 to January 2012. The ducted inverter system did not offer a zone controller, so it functioned as a single zone system. Due to this fact, the registers had to be manually adjusted in order to better maintain consistent temperatures between the two levels of the house. The predicted heating season energy use for the ducted inverter system, based on the measured energy use, was 30% less than that of the baseline system for the typical meteorological year. However, the baseline system was unable to operate in its high stage due to a wiring issue with the zone controller. This resulted in additional resistance heat use during the winter and therefore higher energy use than would be expected in a properly performing unit. The AHRI ratings would indicate that the baseline system would use less energy than the ducted inverter system, which is opposite to the results of this study. During the cooling season, the ducted inverter system was predicted to use 23% more energy than the baseline system during the typical meteorological year. This is also opposite of the results expected by comparing the AHRI ratings. After a detailed comparison of the ducted inverter system's power use compared to that of a recently installed identical system at a retro-fit study house, there is concern that the unit is not operating as intended. The power use and cycles indicate t

  15. A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature ...

  16. Systems and methods for controlling energy use in a building management system using energy budgets

    DOE Patents [OSTI]

    Wenzel, Michael J; Drees, Kirk H

    2014-09-23

    Systems and methods for limiting power consumption by a heating, ventilation, and air conditioning (HVAC) subsystem of a building are shown and described. A feedback controller is used to generate a manipulated variable based on an energy use setpoint and a measured energy use. The manipulated variable may be used for adjusting the operation of an HVAC device.

  17. Safety equipment list for the light duty utility arm system

    SciTech Connect (OSTI)

    Barnes, G.A.

    1998-03-02

    The initial issue (Revision 0) of this Safety Equipment List (SEL) for the Light Duty Utility Arm (LDUA) requires an explanation for both its existence and its being what it is. All LDUA documentation leading up to creation of this SEL, and the SEL itself, is predicated on the LDUA only being approved for use in waste tanks designated as Facility Group 3, i.e., it is not approved for use in Facility Group 1 or 2 waste tanks. Facility Group 3 tanks are those in which a spontaneous or induced hydrogen gas release would be small, localized, and would not exceed 25% of the LFL when mixed with the remaining air volume in the dome space; exceeding these parameters is considered unlikely. Thus, from a NFPA flammable gas environment perspective the waste tank interior is not classified as a hazardous location. Furthermore, a hazards identification and evaluation (HNF-SD-WM-HIE-010, REV 0) performed for the LDUA system concluded that the consequences of actual LDUA system postulated accidents in Flammable Gas Facility Group 3 waste tanks would have either NO IMPACT or LOW IMPACT on the offsite public and onsite worker. Therefore, from a flammable gas perspective, there is not a rationale for classifying any of SSCs associated with the LDUA as either Safety Class (SC) or Safety Significant (SS) SSCs, which, by default, categorizes them as General Service (GS) SSCs. It follows then, based on current PHMC procedures (HNF-PRO-704 and HNF-IP-0842, Vol IV, Section 5.2) for SEL creation and content, and from a flammable gas perspective, that an SEL is NOT REQ@D HOWEVER!!! There is both a precedent and a prudency to capture all SSCS, which although GS, contribute to a Defense-In-Depth (DID) approach to the design and use of equipment in potentially flammable gas environments. This Revision 0 of the LDUA SEL has been created to capture these SSCs and they are designated as GS-DID in this document. The specific reasons for doing this are listed.

  18. DEEP, LOW MASS RATIO OVERCONTACT BINARY SYSTEMS. XIII. DZ PISCIUM WITH INTRINSIC LIGHT VARIABILITY

    SciTech Connect (OSTI)

    Yang, Y.-G.; Dai, H.-F.; Qian, S.-B.; Soonthornthum, B. E-mail: qsb@ynao.ac.cn

    2013-08-01

    New multi-color photometry for the eclipsing binary DZ Psc was performed in 2011 and 2012 using the 85 cm telescope at the Xinglong Station of the National Astronomical Observatories of China. Using the updated Wilson-Devinney (W-D) code, we deduced two sets of photometric solutions. The overcontact degree is f = 89.7({+-} 1.0)%, identifying DZ Psc as a deep, low mass ratio overcontact binary. The asymmetric light curves (i.e., LC{sub 2} in 2012) were modeled by a hot spot on the primary star. Based on all of the available light minimum times, we discovered that the orbital period of DZ Psc may be undergoing a secular period increase with a cyclic variation. The modulated period and semi-amplitude of this oscillation are P{sub mod} = 11.89({+-} 0.19) yr and A = 0.0064({+-} 0.0006) days, which may be possibly attributed to either cyclic magnetic activity or light-time effect due to the third body. The long-term period increases at a rate of dP/dt=+7.43({+-}0.17) Multiplication-Sign 10{sup -7} days yr{sup -1}, which may be interpreted as conserved mass transfer from the less massive component to the more massive one. With mass transferring, DZ Psc will finally merge into a rapid-rotation single star when J{sub spin}/J{sub orb} > 1/3.

  19. System for detecting operating errors in a variable valve timing engine using pressure sensors

    DOE Patents [OSTI]

    Wiles, Matthew A.; Marriot, Craig D

    2013-07-02

    A method and control module includes a pressure sensor data comparison module that compares measured pressure volume signal segments to ideal pressure volume segments. A valve actuation hardware remedy module performs a hardware remedy in response to comparing the measured pressure volume signal segments to the ideal pressure volume segments when a valve actuation hardware failure is detected.

  20. Mathematical Model for Transmutation System with a Two-Member Chain and Variable Separation Coefficients

    SciTech Connect (OSTI)

    Ahn, Joonhong; Kurata, Masaki

    2007-07-01

    Mathematical models for mass flow in a fuel cycle have been established for a two-member chain in a reactor with reductive extraction for partitioning process. A sub-model for reductive extraction has been implemented into the mass flow model. Recursive solutions for the mass fractions of two actinide isotopes and fission products have been obtained as a function of cycle number. As a performance measure, the reduction ratios have been defined for two actinide isotopes. Effects of discharged fuel composition on the partitioning efficiency and on waste generation have been observed. The numerical results show that at early cycles the partitioning efficiency is relatively low because of large mass fractions of actinides in discharged fuel. With more cycles, fission products accumulate, and the partitioning efficiency becomes better, approaching asymptotic values. Consequently, waste generation at early cycles would be greater than at later cycles. (authors)

  1. Continuous-variable quantum teleportation with non-Gaussian resources

    SciTech Connect (OSTI)

    Dell'Anno, F.; De Siena, S.; Albano, L.; Illuminati, F.

    2007-08-15

    We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum, and the, suitably measured, amount of non-Gaussianity.

  2. Analysis of a teetered, variable-speed rotor: final report

    SciTech Connect (OSTI)

    Weber, T.L.; Wilson, R.E.; Walker, S.N. . Dept. of Mechanical Engineering)

    1991-06-01

    A computer model of a horizontal axis wind turbine (HOOT) with four structural degrees of freedom has been derived and verified. The four degrees of freedom include flapwise motion of the blades, teeter motion, and variable rotor speed. Options for the variable rotor speed include synchronous, induction, and constant-tip speed generator models with either start, stop, or normal operations. Verification is made by comparison with analytical solutions and mean and cyclic ESI-80 data. The Veers full-field turbulence model is used as a wind input for a synchronous and induction generator test case during normal operation. As a result of the comparison, it is concluded that the computer model can be used to predict accurately mean and cyclic loads with a turbulent wind input. 47 refs., 19 figs.

  3. Variable-energy collimator for high-energy radiation

    DOE Patents [OSTI]

    Hill, R.A.

    1982-03-03

    An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated ;energy from emergine from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

  4. Diagnostic for two-mode variable valve activation device

    DOE Patents [OSTI]

    Fedewa, Andrew M

    2014-01-07

    A method is provided for diagnosing a multi-mode valve train device which selectively provides high lift and low lift to a combustion valve of an internal combustion engine having a camshaft phaser actuated by an electric motor. The method includes applying a variable electric current to the electric motor to achieve a desired camshaft phaser operational mode and commanding the multi-mode valve train device to a desired valve train device operational mode selected from a high lift mode and a low lift mode. The method also includes monitoring the variable electric current and calculating a first characteristic of the parameter. The method also includes comparing the calculated first characteristic against a predetermined value of the first characteristic measured when the multi-mode valve train device is known to be in the desired valve train device operational mode.

  5. Radiative reverse shock laser experiments relevant to accretion processes in cataclysmic variables

    SciTech Connect (OSTI)

    Krauland, C. M.; Drake, R. P.; Kuranz, C. C.; Sweeney, R.; Grosskopf, M.; Klein, S.; Gillespie, R.; Keiter, P. A.; Loupias, B.; Falize, E.

    2013-05-15

    We discuss the production of radiative reverse shocks in experiments at the Omega-60 laser facility. The ability of this high-intensity laser to impart large energy densities on micron-thin foils makes it feasible to create supersonic plasma flows. Obtaining a radiative reverse shock in the laboratory requires a sufficiently fast flow (∼100 km/s) of a material whose opacity is large enough to produce energetically significant emission from experimentally achievable shocked layers. The reverse shock forms in the flow once it is impeded. This paper presents the first radiographic data of normal incidence, reverse shockwaves. These experiments are primarily motivated by the contribution of radiative reverse shock waves to the evolving dynamics of the cataclysmic variable (CV) system in which they reside. We show similarity properties to suggest that the experimental production of radiative reserve shocks in the laboratory may be scalable to such astrophysical systems.

  6. Variability in Measured Space Temperatures in 60 Homes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Variability in Measured Space Temperatures in 60 Homes David Roberts National Renewable Energy Laboratory Kerylyn Lay EnerNOC (formerly of the National Renewable Energy Laboratory) Technical Report NREL/TP-5500-58059 March 2013 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 *

  7. Variable Speed Fan Retrofits for Computer Room Air Conditioners

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By Lawrence Berkeley National Laboratory Steve Greenberg September 2013 2 Contacts Steve Greenberg Lawrence Berkeley National Laboratory One Cyclotron Road, 90R3111 Berkeley, California 94720 (510) 486-6971 segreenberg@lbl.gov For more information on FEMP, please contact: Will Lintner, P.E., CEM Federal Energy Management

  8. Simulating solar power plant variability : a review of current methods.

    SciTech Connect (OSTI)

    Lave, Matthew; Ellis, Abraham; Stein, Joshua S.

    2013-06-01

    It is important to be able to accurately simulate the variability of solar PV power plants for grid integration studies. We aim to inform integration studies of the ease of implementation and application-specific accuracy of current PV power plant output simulation methods. This report reviews methods for producing simulated high-resolution (sub-hour or even sub-minute) PV power plant output profiles for variability studies and describes their implementation. Two steps are involved in the simulations: estimation of average irradiance over the footprint of a PV plant and conversion of average irradiance to plant power output. Six models are described for simulating plant-average irradiance based on inputs of ground-measured irradiance, satellite-derived irradiance, or proxy plant measurements. The steps for converting plant-average irradiance to plant power output are detailed to understand the contributions to plant variability. A forthcoming report will quantify the accuracy of each method using application-specific validation metrics.

  9. Load sensing system

    DOE Patents [OSTI]

    Sohns, C.W.; Nodine, R.N.; Wallace, S.A.

    1999-05-04

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast inventories of stored nuclear material can be continuously monitored and inventoried of minimal cost. 4 figs.

  10. Extension of latin hypercube samples with correlated variables.

    SciTech Connect (OSTI)

    Hora, Stephen Curtis; Helton, Jon Craig; Sallaberry, Cedric J. PhD.

    2006-11-01

    A procedure for extending the size of a Latin hypercube sample (LHS) with rank correlated variables is described and illustrated. The extension procedure starts with an LHS of size m and associated rank correlation matrix C and constructs a new LHS of size 2m that contains the elements of the original LHS and has a rank correlation matrix that is close to the original rank correlation matrix C. The procedure is intended for use in conjunction with uncertainty and sensitivity analysis of computationally demanding models in which it is important to make efficient use of a necessarily limited number of model evaluations.

  11. Variable temperature electrochemical strain microscopy of Sm-doped ceria

    SciTech Connect (OSTI)

    Jesse, Stephen; Morozovska, A. N.; Kalinin, Sergei V; Eliseev, E. A.; Yang, Nan; Doria, Sandra; Tebano, Antonello

    2013-01-01

    Variable temperature electrochemical strain microscopy has been used to study the electrochemical activity of Sm-doped ceria as a function of temperature and bias. The electrochemical strain microscopy hysteresis loops have been collected across the surface at different temperatures and the relative activity at different temperatures has been compared. The relaxation behavior of the signal at different temperatures has been also evaluated to relate kinetic process during bias induced electrochemical reactions with temperature and two different kinetic regimes have been identified. The strongly non-monotonic dependence of relaxation behavior on temperature is interpreted as evidence for water-mediated mechanisms.

  12. Variable flow control for a nuclear reactor control rod

    DOE Patents [OSTI]

    Carleton, Richard D.; Bhattacharyya, Ajay

    1978-01-01

    A variable flow control for a control rod assembly of a nuclear reactor that depends on turbulent friction though an annulus. The annulus is formed by a piston attached to the control rod drive shaft and a housing or sleeve fitted to the enclosure housing the control rod. As the nuclear fuel is burned up and the need exists for increased reactivity, the control rods are withdrawn, which increases the length of the annulus and decreases the rate of coolant flow through the control rod assembly.

  13. Compare Energy Use in Variable Refrigerant Flow Heat Pumps Field Demonstration and Computer Model

    SciTech Connect (OSTI)

    Sharma, Chandan; Raustad, Richard

    2013-06-01

    Variable Refrigerant Flow (VRF) heat pumps are often regarded as energy efficient air-conditioning systems which offer electricity savings as well as reduction in peak electric demand while providing improved individual zone setpoint control. One of the key advantages of VRF systems is minimal duct losses which provide significant reduction in energy use and duct space. However, there is limited data available to show their actual performance in the field. Since VRF systems are increasingly gaining market share in the US, it is highly desirable to have more actual field performance data of these systems. An effort was made in this direction to monitor VRF system performance over an extended period of time in a US national lab test facility. Due to increasing demand by the energy modeling community, an empirical model to simulate VRF systems was implemented in the building simulation program EnergyPlus. This paper presents the comparison of energy consumption as measured in the national lab and as predicted by the program. For increased accuracy in the comparison, a customized weather file was created by using measured outdoor temperature and relative humidity at the test facility. Other inputs to the model included building construction, VRF system model based on lab measured performance, occupancy of the building, lighting/plug loads, and thermostat set-points etc. Infiltration model inputs were adjusted in the beginning to tune the computer model and then subsequent field measurements were compared to the simulation results. Differences between the computer model results and actual field measurements are discussed. The computer generated VRF performance closely resembled the field measurements.

  14. The Kelastic variable wall mining machine. Third quarterly technical report, April 1--July 1, 1997

    SciTech Connect (OSTI)

    1997-12-31

    The Project Team accomplished two tasks during the third quarter: preparation and presentation of professional papers; and development of simulation models and sub models of the hypothetical variable wall mining installation. The project team also continued its search for the suitable animation software to be adapted to the underground mining systems. Meanwhile work is progressing along the lines of updating the original open loop flow diagram that deals with the automatic control of the thrusting, advance, and rotation of the auger train which both cuts (extracts) and transports the coal across the face. The team is integrating the control systems into a deterministic mathematical equation for optimizing the mining and material flow rate in the operating system. The long range plan is to integrate the current deterministic equations in a suitable animation program with a number of adjustable and controllable parameters. This will enable coal operators and engineers to visualize how the variations can affect the safety, cost and production levels of the system.

  15. FINAL REPORT: Reduction in Energy Consumption and Variability in Steel Foundry Operations

    SciTech Connect (OSTI)

    F. Peters

    2005-05-24

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to large process variation. This indicates the need for ongoing monitoring of the process and system to quantify the effort being expended. A system to measure the grinding effort was investigated but did not prove to be successful. A weld wire counting system was shown to be very successful in tracking casting quality by monitoring the quantity of weld wire being expended on a per casting basis. Further use of such systems is highly recommended. The field studies showed that the visual inspection process for the casting surface was a potentially large source of process variation. Measurement system analysis studies were conducted at three steel casting producers. The tests measured the consistency of the inspectors in identifying the same surface anomalies. The repeatability (variation of the same operator inspecting the same casting) was found to be relatively consistent across the companies at about 60-70%. However, this is still are very large amount of variation. Reproducibility (variation of different operators inspecting the same casting) was worse, ranging between 20 to 80% at the three locations. This large amount of variation shows that there is a great opportunity for improvement. Falsely identifying anomalies for reworking will cause increased expense and energy consumption. This is particularly true if a weld repair and repeated heat treatment is required. However, not identifying an anomaly could also result in future rework processing, a customer return, or scrap. To help alleviate this problem, casting surface comparator plates were developed and distributed to the industry. These plates are very inexpensive which enables them to be provided to all those involved with casting surface quality, such as operators, inspectors, sales, and management.

  16. Control studies of an automotive turbocharged diesel engine with variable geometry turbine

    SciTech Connect (OSTI)

    Winterbone, D.E.; Jai In, S.

    1988-01-01

    Major advances are being made in engine hardware, control theories and microcomputer technology. The application of advanced control and monitoring techniques to engines should enable them to meet all the restrictions imposed upon them while they operate to their full potential. Variable geometry turbocharging of automotive diesel engines is a good example of a case where the control implications need to be considered carefully. This paper reports a technique for developing the dynamic characteristics of turbocharged diesel engines with variable geometry turbine and compares the results with measurements obtained on an engine. It is the first step in the design process for a true, dynamic, multivariable controller. Most current systems are simply scheduling devices with little understanding or consideration of possible interactions between various control loops. A non-linear simulation model for a turbocharged diesel engine was used to investigate the performance of the engine. Major features of the program, aspects of constructing a model for control purposes and identification procedures of the engine dynamic are discussed.

  17. Uncovering the intrinsic variability of gamma-ray bursts

    SciTech Connect (OSTI)

    Golkhou, Vahid Z.; Butler, Nathaniel R., E-mail: vgolkhou@asu.edu, E-mail: natbutler@asu.edu [Cosmology Initiative, Arizona State University, Tempe, AZ 85287, USA. (United States)

    2014-05-20

    We develop a robust technique to determine the minimum variability timescale for gamma-ray burst (GRB) light curves, utilizing Haar wavelets. Our approach averages over the data for a given GRB, providing an aggregate measure of signal variation while also retaining sensitivity to narrow pulses within complicated time series. In contrast to previous studies using wavelets, which simply define the minimum timescale in reference to the measurement noise floor, our approach identifies the signature of temporally smooth features in the wavelet scaleogram and then additionally identifies a break in the scaleogram on longer timescales as a signature of a true, temporally unsmooth light curve feature or features. We apply our technique to the large sample of Swift GRB gamma-ray light curves and for the first timedue to the presence of a large number of GRBs with measured redshiftdetermine the distribution of minimum variability timescales in the source frame. We find a median minimum timescale for long-duration GRBs in the source frame of ?t {sub min} = 0.5 s, with the shortest timescale found being on the order of 10 ms. This short timescale suggests a compact central engine (3 10{sup 3} km). We discuss further implications for the GRB fireball model and present a tantalizing correlation between the minimum timescale and redshift, which may in part be due to cosmological time dilation.

  18. Survey of Variable Generation Forecasting in the West: August 2011 - June 2012

    SciTech Connect (OSTI)

    Porter, K.; Rogers, J.

    2012-04-01

    This report surveyed Western Interconnection Balancing Authorities regarding their implementation of variable generation forecasting, the lessons learned to date, and recommendations they would offer to other Balancing Authorities who are considering variable generation forecasting. Our survey found that variable generation forecasting is at an early implementation stage in the West. Eight of the eleven Balancing Authorities interviewed began forecasting in 2008 or later. It also appears that less than one-half of the Balancing Authorities in the West are currently utilizing variable generation forecasting, suggesting that more Balancing Authorities in the West will engage in variable generation forecasting should more variable generation capacity be added.

  19. HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING

    Office of Scientific and Technical Information (OSTI)

    OPTICAL VARIABILITY (Journal Article) | SciTech Connect HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING OPTICAL VARIABILITY Citation Details In-Document Search Title: HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING OPTICAL VARIABILITY We identify 3113 highly variable objects in 7200 deg{sup 2} of the Palomar-QUEST (PQ) Survey, which each varied by more than 0.4 mag simultaneously in two broadband optical filters on timescales from hours

  20. A new variable-resolution associative memory for high energy physics

    SciTech Connect (OSTI)

    Annovi, A.; Amerio, S.; Beretta, M.; Bossini, E.; Crescioli, F.; Dell'Orso, M.; Giannetti, P.; Hoff, J.; Liu, T.; Magalotti, D.; Piendibene, M.; Sacco, I.; Schoening, A.; Soltveit, H. K.; Stabile, A.; Tripiccione, R.; Liberali, V.; Vitillo, R.; Volpi, G.

    2011-07-01

    We describe an important advancement for the Associative Memory device (AM). The AM is a VLSI processor for pattern recognition based on Content Addressable Memory (CAM) architecture. The AM is optimized for on-line track finding in high-energy physics experiments. Pattern matching is carried out by finding track candidates in coarse resolution 'roads'. A large AM bank stores all trajectories of interest, called 'patterns', for a given detector resolution. The AM extracts roads compatible with a given event during detector read-out. Two important variables characterize the quality of the AM bank: its 'coverage' and the level of fake roads. The coverage, which describes the geometric efficiency of a bank, is defined as the fraction of tracks that match at least one pattern in the bank. Given a certain road size, the coverage of the bank can be increased just adding patterns to the bank, while the number of fakes unfortunately is roughly proportional to the number of patterns in the bank. Moreover, as the luminosity increases, the fake rate increases rapidly because of the increased silicon occupancy. To counter that, we must reduce the width of our roads. If we decrease the road width using the current technology, the system will become very large and extremely expensive. We propose an elegant solution to this problem: the 'variable resolution patterns'. Each pattern and each detector layer within a pattern will be able to use the optimal width, but we will use a 'don't care' feature (inspired from ternary CAMs) to increase the width when that is more appropriate. In other words we can use patterns of variable shape. As a result we reduce the number of fake roads, while keeping the efficiency high and avoiding excessive bank size due to the reduced width. We describe the idea, the implementation in the new AM design and the implementation of the algorithm in the simulation. Finally we show the effectiveness of the 'variable resolution patterns' idea using simulated high occupancy events in the ATLAS detector. (authors)

  1. The variable wall mining machine. Third quarterly technical report, April 1, 1994--June 30, 1994

    SciTech Connect (OSTI)

    Not Available

    1994-08-20

    This is the Third Technical Report to develop the Variable Wall Mining Machine(VWM), a patented mining system that has the potential of greatly improving the underground mining of coal and other flat-lying mineral beds by providing a greater safety for workers, a healthier human environment, and a higher productivity. One of the thrusts of this project is to analyze the adaptation of the VWM system to a dual duct ventilation system which separates the air for human breathing from the air which becomes contaminated from dust and dangerous gases. In conventional practice there is one zone in an underground working section where workers breathe the air used to carry away gases and dust. A proposed dual duct system divides the single zone into two zones: one for cutting and fragmentation and one for worker occupancy. It is both technically and economically impossible to ventilate longwall face with the conventional method when methane emission rate is higher than 1,500 cfM. The only available option to the methane problem is to pre-drain the methane before mining so the methane emission rate will be lower later during longwall mining. But it is questionable that enough methane can be predrained to significantly erase the explosibility problem. Contrariwise, the dual-duct gas control method requires significantly less ventilating air, resulting in large savings in fans, air course construction, and energy. The overall costs are measurably less. Since the cutting chamber is sealed, the dust and methane are extracted from the mine in a separate ventilation system at a speed which is independent of the general mine ventilation system.

  2. Extrans - Permeation Measurement System - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Extrans - Permeation Measurement System Y-12 National Security Complex Contact Y12 About This Technology Publications: PDF Document Publication Fact Sheet (695 KB) PDF Document Publication Patent (156 KB) Technology Marketing SummaryThe Extrans Permeation Measurement System is a customizable system for testing the behavior and uniformity of polymers and other materials. The system can be used to determine permeation rates using variable temperatures, total pressures, differential pressures, and

  3. Flow and Containment Transport Code for Modeling Variably Saturated Porous Media

    Energy Science and Technology Software Center (OSTI)

    1998-05-14

    FACT is a finite element based code designed to model subsurface flow and contaminant transport. It was designed to perform transient three-dimensional calculations that simulate isothermal groundwater flow, moisture movement, and solute transport in variably saturated and fully saturated subsurface porous media. The code is designed specifically to handle complex multi-layer and/or heterogenous aquifer systems in an efficient manner and accommodates a wide range of boundary conditions. Additionally 1-D and 2-D (in Cartesian coordinates) problemsmore » are handled in FACT by simply limiting the number of elements in a particular direction(s) to one. The governing equations in FACT are formulated only in Cartesian coordinates. FACT writes out both ascii and graphical binary files that are TECPLOT-ready. Special features are also available within FACT for handling the typical groundwater modeling needs for remediation efforts at the Savannah River Site.« less

  4. Fixed-Speed and Variable-Slip Wind Turbines Providing Spinning Reserves to the Grid: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Singh, M.; Gevorgian, V.

    2012-11-01

    As the level of wind penetration increases, wind turbine technology must move from merely generating power from wind to taking a role in supporting the bulk power system. Wind turbines should have the capability to provide inertial response and primary frequency (governor) response so they can support the frequency stability of the grid. To provide governor response, wind turbines should be able to generate less power than the available wind power and hold the rest in reserve, ready to be accessed as needed. This paper explores several ways to control wind turbine output to enable reserve-holding capability. This paper focuses on fixed-speed (also known as Type 1) and variable-slip (also known as Type 2) turbines.

  5. Flow and Containment Transport Code for Modeling Variably Saturated Porous Media

    Energy Science and Technology Software Center (OSTI)

    1998-05-14

    FACT is a finite element based code designed to model subsurface flow and contaminant transport. It was designed to perform transient three-dimensional calculations that simulate isothermal groundwater flow, moisture movement, and solute transport in variably saturated and fully saturated subsurface porous media. The code is designed specifically to handle complex multi-layer and/or heterogenous aquifer systems in an efficient manner and accommodates a wide range of boundary conditions. Additionally 1-D and 2-D (in Cartesian coordinates) problemsmore »are handled in FACT by simply limiting the number of elements in a particular direction(s) to one. The governing equations in FACT are formulated only in Cartesian coordinates. FACT writes out both ascii and graphical binary files that are TECPLOT-ready. Special features are also available within FACT for handling the typical groundwater modeling needs for remediation efforts at the Savannah River Site.« less

  6. Simulation of the intraseasonal variability over the Eastern...

    Office of Scientific and Technical Information (OSTI)

    exerts significant influences on regional climateweather systems, investigation of contemporary model capabilities in representing these ISV modes over the EPAC is limited. In...

  7. Dromion-like structures and stability analysis in the variable...

    Office of Scientific and Technical Information (OSTI)

    for some nonlinear phenomena in fiber laser systems, and understanding the essential ... National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of ...

  8. Variable Grid Method for Visualizing Uncertainty Associated with...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interpretation. In general, NETL's VGM applies a grid system where the size of the cell represents the uncertainty associated with the original point data sources or their...

  9. Grid Integration and the Carrying Capacity of the U.S. Grid to Incorporate Variable Renewable Energy

    SciTech Connect (OSTI)

    Cochran, Jaquelin; Denholm, Paul; Speer, Bethany; Miller, Mackay

    2015-04-23

    In the United States and elsewhere, renewable energy (RE) generation supplies an increasingly large percentage of annual demand, including nine U.S. states where wind comprised over 10% of in-state generation in 2013. This white paper summarizes the challenges to integrating increasing amounts of variable RE, identifies emerging practices in power system planning and operation that can facilitate grid integration, and proposes a unifying concept—economic carrying capacity—that can provide a framework for evaluating actions to accommodate higher penetrations of RE. There is growing recognition that while technical challenges to variable RE integration are real, they can generally be addressed via a variety of solutions that vary in implementation cost. As a result, limits to RE penetration are primarily economic, driven by factors that include transmission and the flexibility of the power grid to balance supply and demand. This limit can be expressed as economic carrying capacity, or the point at which variable RE is no longer economically competitive or desirable to the system or society.

  10. IMPROVED VARIABLE STAR SEARCH IN LARGE PHOTOMETRIC DATA SETS: NEW VARIABLES IN CoRoT FIELD LRa02 DETECTED BY BEST II

    SciTech Connect (OSTI)

    Fruth, T.; Cabrera, J.; Csizmadia, Sz.; Eigmueller, P.; Erikson, A.; Kirste, S.; Pasternacki, T.; Rauer, H.; Titz-Weider, R.; Kabath, P.; Chini, R.; Lemke, R.; Murphy, M.

    2012-06-15

    The CoRoT field LRa02 has been observed with the Berlin Exoplanet Search Telescope II (BEST II) during the southern summer 2007/2008. A first analysis of stellar variability led to the publication of 345 newly discovered variable stars. Now, a deeper analysis of this data set was used to optimize the variability search procedure. Several methods and parameters have been tested in order to improve the selection process compared to the widely used J index for variability ranking. This paper describes an empirical approach to treat systematic trends in photometric data based upon the analysis of variance statistics that can significantly decrease the rate of false detections. Finally, the process of reanalysis and method improvement has virtually doubled the number of variable stars compared to the first analysis by Kabath et al. A supplementary catalog of 272 previously unknown periodic variables plus 52 stars with suspected variability is presented. Improved ephemerides are given for 19 known variables in the field. In addition, the BEST II results are compared with CoRoT data and its automatic variability classification.

  11. Turbocharger with variable nozzle having vane sealing surfaces

    DOE Patents [OSTI]

    Arnold, Philippe (Hennecourt, FR); Petitjean, Dominique (Julienrupt, FR); Ruquart, Anthony (Thaon les Vosges, FR); Dupont, Guillaume (Thaon les Vosges, FR); Jeckel, Denis (Thaon les Vosges, FR)

    2011-11-15

    A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) at least one step that defines sealing surfaces positioned to be substantially abutted by airfoil surfaces of the vanes in the closed position of the vanes and to be spaced from the airfoil surfaces in positions other than the closed position. This substantial abutment between the airfoil surfaces and the sealing surfaces serves to substantially prevent exhaust gas from leaking past the ends of the airfoil portions. At the same time, clearances between the nozzle ring face and the end faces of the airfoil portions can be sufficiently large to prevent binding of the vanes under all operating conditions.

  12. Cataclysmic variables in the SUPERBLINK proper motion survey

    SciTech Connect (OSTI)

    Skinner, Julie N.; Thorstensen, John R.; Lpine, Sbastien

    2014-12-01

    We have discovered a new high proper motion cataclysmic variable (CV) in the SUPERBLINK proper motion survey, which is sensitive to stars with proper motions greater than 40 mas yr{sup ?1}. This CV was selected for follow-up observations as part of a larger search for CVs selected based on proper motions and their near-UV?V and V?K{sub s} colors. We present spectroscopic observations from the 2.4 m Hiltner Telescope at MDM Observatory. The new CV's orbital period is near 96 minutes, its spectrum shows the double-peaked Balmer emission lines characteristic of quiescent dwarf novae, and its V magnitude is near 18.2. Additionally, we present a full list of known CVs in the SUPERBLINK catalog.

  13. Variable-metric diffraction crystals for x-ray optics

    SciTech Connect (OSTI)

    Smither, R.K.; Fernandez, P.B. )

    1992-02-01

    A variable-metric (VM) crystal is one in which the spacing between the crystalline planes changes with position in the crystal. This variation can be either parallel to the crystalline planes or perpendicular to the crystalline planes of interest and can be produced by either introducing a thermal gradient in the crystal or by growing a crystal made of two or more elements and changing the relative percentages of the two elements as the crystal is grown. A series of experiments were performed in the laboratory to demonstrate the principle of the variable-metric crystal and its potential use in synchrotron beam lines. One of the most useful applications of the VM crystal is to increase the number of photons per unit bandwidth in a diffracted beam without losing any of the overall intensity. In a normal synchrotron beam line that uses a two-crystal monochromator, the bandwidth of the diffracted photon beam is determined by the vertical opening angle of the beam which is typically 0.10--0.30 mrad or 20--60 arcsec. When the VM crystal approach is applied, the bandwidth of the beam can be made as narrow as the rocking curve of the diffracting crystal, which is typically 0.005--0.050 mrad or 1--10 arcsec. Thus a very large increase of photons per unit bandwidth (or per unit energy) can be achieved through the use of VM crystals. When the VM principle is used with bent crystals, new kinds of x-ray optical elements can be generated that can focus and defocus x-ray beams much like simple lenses where the focal length of the lens can be changed to match its application. Thus both large magnifications and large demagnifications can be achieved as well as parallel beams with narrow bandwidths.

  14. A High Temperature Hermetic Primer and a Variable Spring Tester

    SciTech Connect (OSTI)

    Begeal, D.R.

    1994-05-01

    Percussion primers are used at Sandia to ignite energetic components such as pyrotechnic actuators and thermal batteries. This report describes a High Temperature Hermetic Primer (HTHP) that was developed to replace a previous G16 Percussion Primer Subassembly (Gl6PPS). The ignition mix in these primers is the same as in the discontinued Remington 44G16 (KC1O{sub 3}, SbS{sub 3}, and Ca{sub 2}Si). The HTHP has nearly the same sensitivity as the 44G16 and a significantly lower sensitivity than the G16PPS. In parallel with the HTHP development, we also designed a Variable Spring Tester (VST) to determine percussion primer ignition sensitivity with firing pins that have the same mass as those used in field applications. The tester is capable of accelerating firing pins over a velocity range of 100 to 600 inches per second for pins weighing up to 6 grams. The desired impulse can be preselected with an accuracy of better than {plus_minus}1%. The actual impulse is measured on every shot. The VST was characterized using the WW42Cl primer, as well as with the G16PPS and the HTHP. Compared to data from conventional ball drop testers, we found that ignition sensitivities were lower and there was less scatter in the sensitivity data. Our experiments indicate that ignition sensitivity is not strictly energy dependent, but also depends on the rate of deposition, or firing pin velocity in this case. Development results for the HTHP and Variable Spring Tester are discussed and design details are shown.

  15. The LCLS variable-energy hard X-ray single-shot spectrometer

    SciTech Connect (OSTI)

    Rich, David; Zhu, Diling; Turner, James; Zhang, Dehong; Hill, Bruce; Feng, Yiping

    2016-01-01

    The engineering design, implementation, operation and performance of the new variable-energy hard X-ray single-shot spectrometer (HXSSS) for the LCLS free-electron laser (FEL) are reported. The HXSSS system is based on a cylindrically bent Si thin crystal for dispersing the incident polychromatic FEL beam. A spatially resolved detector system consisting of a Ce:YAG X-ray scintillator screen, an optical imaging system and a low-noise pixelated optical camera is used to record the spectrograph. The HXSSS provides single-shot spectrum measurements for users whose experiments depend critically on the knowledge of the self-amplified spontaneous emission FEL spectrum. It also helps accelerator physicists for the continuing studies and optimization of self-seeding, various improved mechanisms for lasing mechanisms, and FEL performance improvements. The designed operating energy range of the HXSSS is from 4 to 20 keV, with the spectral range of order larger than 2% and a spectral resolution of 2 10-5or better. Those performance goals have all been achieved during the commissioning of the HXSSS.

  16. The LCLS variable-energy hard X-ray single-shot spectrometer

    SciTech Connect (OSTI)

    Rich, David; Zhu, Diling; Turner, James; Zhang, Dehong; Hill, Bruce; Feng, Yiping

    2016-01-01

    The engineering design, implementation, operation and performance of the new variable-energy hard X-ray single-shot spectrometer (HXSSS) for the LCLS free-electron laser (FEL) are reported. The HXSSS system is based on a cylindrically bent Si thin crystal for dispersing the incident polychromatic FEL beam. A spatially resolved detector system consisting of a Ce:YAG X-ray scintillator screen, an optical imaging system and a low-noise pixelated optical camera is used to record the spectrograph. The HXSSS provides single-shot spectrum measurements for users whose experiments depend critically on the knowledge of the self-amplified spontaneous emission FEL spectrum. It also helps accelerator physicists for the continuing studies and optimization of self-seeding, various improved mechanisms for lasing mechanisms, and FEL performance improvements. The designed operating energy range of the HXSSS is from 4 to 20 keV, with the spectral range of order larger than 2% and a spectral resolution of 2 10-5or better. Those performance goals have all been achieved during the commissioning of the HXSSS.

  17. Combustion pinhole camera system

    DOE Patents [OSTI]

    Witte, Arvel B. (Rolling Hills, CA)

    1984-02-21

    A pinhole camera system utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

  18. Combustion pinhole camera system

    DOE Patents [OSTI]

    Witte, A.B.

    1984-02-21

    A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor. 2 figs.

  19. Monte-Carlo particle dynamics in a variable specific impulse...

    Office of Scientific and Technical Information (OSTI)

    Authors: Ilin, A.V. 1 ; Diaz, F.R.C. ; Squire, J.P. 2 ; Carter, M.D. 3 + Show Author Affiliations Lockheed Martin Space Mission Systems and Services, Houston, TX (United ...

  20. OBSERVATIONS OF THERMAL FLARE PLASMA WITH THE EUV VARIABILITY EXPERIMENT

    SciTech Connect (OSTI)

    Warren, Harry P.; Doschek, George A. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Mariska, John T. [School of Physics, Astronomy, and Computational Sciences, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

    2013-06-20

    One of the defining characteristics of a solar flare is the impulsive formation of very high temperature plasma. The properties of the thermal emission are not well understood, however, and the analysis of solar flare observations is often predicated on the assumption that the flare plasma is isothermal. The EUV Variability Experiment (EVE) on the Solar Dynamics Observatory provides spectrally resolved observations of emission lines that span a wide range of temperatures (e.g., Fe XV-Fe XXIV) and allow for thermal flare plasma to be studied in detail. In this paper we describe a method for computing the differential emission measure distribution in a flare using EVE observations and apply it to several representative events. We find that in all phases of the flare the differential emission measure distribution is broad. Comparisons of EVE spectra with calculations based on parameters derived from the Geostationary Operational Environmental Satellites soft X-ray fluxes indicate that the isothermal approximation is generally a poor representation of the thermal structure of a flare.

  1. Future warming patterns linked to today’s climate variability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dai, Aiguo

    2016-01-11

    The reliability of model projections of greenhouse gas (GHG)-induced future climate change is often assessed based on models’ ability to simulate the current climate, but there has been little evidence that connects the two. In fact, this practice has been questioned because the GHG-induced future climate change may involve additional physical processes that are not important for the current climate. Here I show that the spatial patterns of the GHG-induced future warming in the 21st century is highly correlated with the patterns of the year-to-year variations of surface air temperature for today’s climate, with areas of larger variations during 1950–1979more » having more GHG-induced warming in the 21st century in all climate models. Such a relationship also exists in other climate fields such as atmospheric water vapor, and it is evident in observed temperatures from 1950–2010. The results suggest that many physical processes may work similarly in producing the year-to-year climate variations in the current climate and the GHG-induced long-term changes in the 21st century in models and in the real world. Furthermore, they support the notion that models that simulate present-day climate variability better are likely to make more reliable predictions of future climate change.« less

  2. Method and apparatus for controlling continuously variable transmission for vehicle

    SciTech Connect (OSTI)

    Osanai, A.; Niwa, T.; Gono, T.

    1987-04-14

    A method is described of controlling a speed ratio of a continuously variable transmission for a vehicle for transmitting a rotary motion of an engine of the vehicle to drive wheels of the vehicle with a stepless speed change. The speed ratio of the transmission is regulated such that an actual speed of the engine coincides with a target engine speed. The method comprises: determining a first target speed of the engine based on a predetermined currently required output of the engine and according to a predetermined relation between the first target speed of the engine and the required output of the engine. The first target speed of the engine is normally used as the target engine speed to regulate the speed ratio of the transmission; detecting a running speed of the vehicle; and determining a second target speed of the engine based on a predetermined transmission efficiency of the transmission and on the first target speed of the engine. The second target speed of the engine is lower than the first target speed.

  3. Estimating the age of alleles by use of intraallelic variability

    SciTech Connect (OSTI)

    Slatkin, M.; Rannala, B.

    1997-02-01

    A method is presented for estimating the age of an allele by use of its frequency and the extent of variation among different copies. The method uses the joint distribution of the number of copies in a population sample and the coalescence times of the intraallelic gene genealogy conditioned on the number of copies. The linear birth-death process is used to approximate the dynamics of a rare allele in a finite population. A maximum-likelihood estimate of the age of the allele is obtained by Monte Carlo integration over the coalescence times. The method is applied to two alleles at the cystic fibrosis (CFTR) locus, {Delta}F508 and G542X, for which intraallelic variability at three intronic microsatellite loci has been examined. Our results indicate that G542X is somewhat older than {Delta}F508. Although absolute estimates depend on the mutation rates at the microsatellite loci, our results support the hypothesis that {Delta}F508 arose <500 generations ({approx}10,000 years) ago. 32 refs., 4 figs.

  4. Continuous Variable Cluster State Generation over the Optical Spatial Mode Comb

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pooser, Raphael C.; Jing, Jietai

    2014-10-20

    One way quantum computing uses single qubit projective measurements performed on a cluster state (a highly entangled state of multiple qubits) in order to enact quantum gates. The model is promising due to its potential scalability; the cluster state may be produced at the beginning of the computation and operated on over time. Continuous variables (CV) offer another potential benefit in the form of deterministic entanglement generation. This determinism can lead to robust cluster states and scalable quantum computation. Recent demonstrations of CV cluster states have made great strides on the path to scalability utilizing either time or frequency multiplexingmore » in optical parametric oscillators (OPO) both above and below threshold. The techniques relied on a combination of entangling operators and beam splitter transformations. Here we show that an analogous transformation exists for amplifiers with Gaussian inputs states operating on multiple spatial modes. By judicious selection of local oscillators (LOs), the spatial mode distribution is analogous to the optical frequency comb consisting of axial modes in an OPO cavity. We outline an experimental system that generates cluster states across the spatial frequency comb which can also scale the amount of quantum noise reduction to potentially larger than in other systems.« less

  5. Magnitude and Variability of Controllable Charge Capacity Provided by Grid Connected Plug-in Electric Vehicles

    SciTech Connect (OSTI)

    Scoffield, Don R; Smart, John; Salisbury, Shawn

    2015-03-01

    As market penetration of plug-in electric vehicles (PEV) increases over time, the number of PEVs charging on the electric grid will also increase. As the number of PEVs increases, their ability to collectively impact the grid increases. The idea of a large body of PEVs connected to the grid presents an intriguing possibility. If utilities can control PEV charging, it is possible that PEVs could act as a distributed resource to provide grid services. The technology required to control charging is available for modern PEVs. However, a system for wide-spread implementation of controllable charging, including robust communication between vehicles and utilities, is not currently present. Therefore, the value of controllable charging must be assessed and weighed against the cost of building and operating such as system. In order to grasp the value of PEV charge control to the utility, the following must be understood: 1. The amount of controllable energy and power capacity available to the utility 2. The variability of the controllable capacity from day to day and as the number of PEVs in the market increases.

  6. NREL: Energy Systems Integration - NREL Assesses Costs of Adding...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to Existing Power Systems September 29, 2015 Much effort has been made to assess the costs associated with integrating variable generation (VG) such as wind and solar into an...

  7. Galilei invariant technique for quantum system description

    SciTech Connect (OSTI)

    Kamuntavi?ius, Gintautas P.

    2014-04-15

    Problems with quantum systems models, violating Galilei invariance are examined. The method for arbitrary non-relativistic quantum system Galilei invariant wave function construction, applying a modified basis where center-of-mass excitations have been removed before Hamiltonian matrix diagonalization, is developed. For identical fermion system, the Galilei invariant wave function can be obtained while applying conventional antisymmetrization methods of wave functions, dependent on single particle spatial variables.

  8. Flexibility in 21st Century Power Systems

    SciTech Connect (OSTI)

    Cochran, J.; Miller, M.; Zinaman, O.; Milligan, M.; Arent, D.; Palmintier, B.; O'Malley, M.; Mueller, S.; Lannoye, E.; Tuohy, A.; Kujala, B.; Sommer, M.; Holttinen, H.; Kiviluoma, J.; Soonee, S. K.

    2014-05-01

    Flexibility of operation--the ability of a power system to respond to change in demand and supply--is a characteristic of all power systems. Flexibility is especially prized in twenty-first century power systems, with higher levels of grid-connected variable renewable energy (primarily, wind and solar). This paper summarizes the analytic frameworks that have emerged to measure this characteristic and distills key principles of flexibility for policy makers.

  9. Systems Analysis Success Stories | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Systems Analysis Success Stories Systems Analysis Success Stories June 9, 2015 Systems Analysis Success Stories Energy Department Honored for Inroads in Geothermal Energy As renewable energy takes a stronger role in supplying the U.S. grid, geothermal power could support a more flexible role to balance the intermittent and variable capacity of wind and solar. May 14, 2015 Through funding by the Energy Department, Sandia National Laboratories have refined a useful percussive hammer tool for harsh

  10. Adjusting the specificity of an engine map based on the sensitivity of an engine control parameter relative to a performance variable

    DOE Patents [OSTI]

    Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

    2014-10-28

    Methods and systems for engine control optimization are provided. A first and a second operating condition of a vehicle engine are detected. An initial value is identified for a first and a second engine control parameter corresponding to a combination of the detected operating conditions according to a first and a second engine map look-up table. The initial values for the engine control parameters are adjusted based on a detected engine performance variable to cause the engine performance variable to approach a target value. A first and a second sensitivity of the engine performance variable are determined in response to changes in the engine control parameters. The first engine map look-up table is adjusted when the first sensitivity is greater than a threshold, and the second engine map look-up table is adjusted when the second sensitivity is greater than a threshold.

  11. ARM Surface Meteorology Systems Instrument Handbook

    SciTech Connect (OSTI)

    Ritsche, MT

    2011-03-08

    The ARM Surface Meteorology Systems consist mainly of conventional in situ sensors that obtain a defined core set of measurements. The core set of measurements is: Barometric Pressure (kPa), Temperature (C), Relative Humidity (%), Arithmetic-Averaged Wind Speed (m/s), Vector-Averaged Wind Speed (m/s), and Vector-Averaged Wind Direction (deg). The sensors that collect the core variables are mounted at the standard heights defined for each variable: Winds: 10 meters Temperature and Relative Humidity: 2 meters Barometric Pressure: 1 meter. Depending upon the geographical location, different models and types of sensors may be used to measure the core variables due to the conditions experienced at those locations. Most sites have additional sensors that measure other variables that are unique to that site or are well suited for the climate of the location but not at others.

  12. Luminous blue variables and superluminous supernovae from binary mergers

    SciTech Connect (OSTI)

    Justham, Stephen; Podsiadlowski, Philipp; Vink, Jorick S. E-mail: podsi@astro.ox.ac.uk

    2014-12-01

    Evidence suggests that the direct progenitor stars of some core-collapse supernovae (CCSNe) are luminous blue variables (LBVs), perhaps including some Type II 'superluminous supernovae' (SLSNe). We examine models in which massive stars gain mass soon after the end of core hydrogen burning. These are mainly intended to represent mergers following a brief contact phase during early Case B mass transfer, but may also represent stars which gain mass in the Hertzsprung Gap or extremely late during the main-sequence phase for other reasons. The post-accretion stars spend their core helium-burning phase as blue supergiants (BSGs), and many examples are consistent with being LBVs at the time of core collapse. Other examples are yellow supergiants at explosion. We also investigate whether such post-accretion stars may explode successfully after core collapse. The final core properties of post-accretion models are broadly similar to those of single stars with the same initial mass as the pre-merger primary star. More surprisingly, when early Case B accretion does affect the final core properties, the effect appears likely to favor a successful SN explosion, i.e., to make the core properties more like those of a lower-mass single star. However, the detailed structures of these cores sometimes display qualitative differences to any single-star model we have calculated. The rate of appropriate binary mergers may match the rate of SNe with immediate LBV progenitors; for moderately optimistic assumptions we estimate that the progenitor birthrate is ?1% of the CCSN rate.

  13. Review of Literature on Terminal Box Control, Occupancy Sensing Technology and Multi-zone Demand Control Ventilation (DCV)

    SciTech Connect (OSTI)

    Liu, Guopeng; Dasu, Aravind R.; Zhang, Jian

    2012-03-01

    This report presents an overall review of the standard requirement, the terminal box control, occupancy sensing technology and DCV. There is system-specific guidance for single-zone systems, but DCV application guidance for multi-zone variable air volume (VAV) systems is not available. No real-world implementation case studies have been found using the CO2-based DCV. The review results also show that the constant minimum air flow set point causes excessive fan power consumption and potential simultaneous heating and cooling. Occupancy-based control (OBC) is needed for the terminal box in order to achieve deep energy savings. Key to OBC is a technology for sensing the actual occupancy of the zone served in real time. Several technologies show promise, but none currently fully meets the need with adequate accuracy and sufficiently low cost.

  14. Accounting for sub-pixel variability of clouds and/or unresolved spectral variability, as needed, with generalized radiative transfer theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Davis, Anthony B.; Xu, Feng; Collins, William D.

    2015-03-01

    Atmospheric hyperspectral VNIR sensing struggles with sub-pixel variability of clouds and limited spectral resolution mixing molecular lines. Our generalized radiative transfer model addresses both issues with new propagation kernels characterized by power-law decay in space.

  15. A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Temperature Combustion | Department of Energy A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel Partnership and 21st Century Truck Programs. PDF icon 2006_deer_hou.pdf More Documents & Publications Adaptive PCCI with Variable Orifice

  16. Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma

    Office of Scientific and Technical Information (OSTI)

    rocket (Journal Article) | SciTech Connect Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma rocket Citation Details In-Document Search Title: Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma rocket The self-consistent mathematical model in a Variable Specific Impulse Magnetoplasma Rocket (VASIMR) is examined. Of particular importance is the effect of a magnetic nozzle in enhancing the axial momentum of the exhaust. Also, different

  17. A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard A.

    2013-01-01

    This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

  18. System Diagram

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    System Diagram System Diagram Diagram of I/O architecture on Hopper Diagram of external I/O services on the Hopper system Last edited: 2016-02-01 08:07:48

  19. System Diagram

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    System Diagram System Diagram Diagram of IO architecture on Hopper Diagram of external IO services on the Hopper system Last edited: 2011-04-14 15:11:1...

  20. Hybrid Energy System Modeling in Modelica

    SciTech Connect (OSTI)

    William R. Binder; Christiaan J. J. Paredis; Humberto E. Garcia

    2014-03-01

    In this paper, a Hybrid Energy System (HES) configuration is modeled in Modelica. Hybrid Energy Systems (HES) have as their defining characteristic the use of one or more energy inputs, combined with the potential for multiple energy outputs. Compared to traditional energy systems, HES provide additional operational flexibility so that high variability in both energy production and consumption levels can be absorbed more effectively. This is particularly important when including renewable energy sources, whose output levels are inherently variable, determined by nature. The specific HES configuration modeled in this paper include two energy inputs: a nuclear plant, and a series of wind turbines. In addition, the system produces two energy outputs: electricity and synthetic fuel. The models are verified through simulations of the individual components, and the system as a whole. The simulations are performed for a range of component sizes, operating conditions, and control schemes.

  1. Session 3: Impact on U.S. Ancillary Services Markets from Variable Renewable Energy (Presentation)

    SciTech Connect (OSTI)

    Cochran, J.

    2013-05-01

    The presentation provides an overview of how increasing penetrations of variable renewable energy on the electricity grid are impacting ancillary services markets in the United States.

  2. File Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    File Systems File Systems For a general description of the different file systems available on PDSF please see Eliza File Systems and Other File Systems. Below is a summary of how ATLAS uses the various systems: /common In the past ATLAS used /common primarily for their software installations but with cvmfs (see below) this is no longer necessary. ATLAS users also have made personal directories under /common/atlas. However, this is not the intended use of /common, as described on Other File

  3. Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump and Heat Recovery Equipment in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard; Nigusse, Bereket; Domitrovic, Ron

    2013-09-30

    The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow heat pump (VRF HP) manufacturers, provided a detailed computer model for a VRF HP system in the United States Department of Energy's (U.S. DOE) EnergyPlus? building energy simulation tool. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance to both the manufacturer's data and that predicted by the use of this new model through computer simulation. The project goal was to investigate the complex interactions of VRF HP systems from an HVAC system perspective, and explore the operational characteristics of this HVAC system type within a laboratory and real world building environment. Detailed laboratory testing of this advanced HVAC system provided invaluable performance information which does not currently exist in the form required for proper analysis and modeling. This information will also be useful for developing and/or supporting test standards for VRF HP systems. Field testing VRF HP systems also provided performance and operational information pertaining to installation, system configuration, and operational controls. Information collected from both laboratory and field tests were then used to create and validate the VRF HP system computer model which, in turn, provides architects, engineers, and building owners the confidence necessary to accurately and reliably perform building energy simulations. This new VRF HP model is available in the current public release version of DOE?s EnergyPlus software and can be used to investigate building energy use in both new and existing building stock. The general laboratory testing did not use the AHRI Standard 1230 test procedure and instead used an approach designed to measure the field installed full-load operating performance. This projects test methodology used the air enthalpy method where relevant air-side parameters were controlled while collecting output performance data at discreet points of steady-state operation. The primary metrics include system power consumption and zonal heating and cooling capacity. Using this test method, the measured total cooling capacity was somewhat lower than reported by the manufacturer. The measured power was found to be equal to or greater than the manufacturers indicated power. Heating capacity measurements produced similar results. The air-side performance metric was total cooling and heating energy since the computer model uses those same metrics as input to the model. Although the sensible and latent components of total cooling were measured, they are not described in this report. The test methodology set the thermostat set point temperature very low for cooling and very high for heating to measure full-load performance and was originally thought to provide the maximum available capacity. Manufacturers stated that this test method would not accurately measure performance of VRF systems which is now believed to be a true statement. Near the end of the project, an alternate test method was developed to better represent VRF system performance as if field installed. This method of test is preliminarily called the Load Based Method of Test where the load is fixed and the indoor conditions and unit operation are allowed to fluctuate. This test method was only briefly attempted in a laboratory setting but does show promise for future lab testing. Since variable-speed air-conditioners and heat pumps include an on-board control algorithm to modulate capacity, these systems are difficult to test. Manufacturers do have the ability to override internal components to accommodate certification procedures, however, it is unknown if the resulting operation is replicated in the field, or if so, how often. Other studies have shown that variable-speed air-conditioners and heat pumps do out perform their single-speed counterparts though these field studies leave as many questions as they do provide answers. The measure

  4. Computer System,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    undergraduate summer institute http:isti.lanl.gov (Educational Prog) 2016 Computer System, Cluster, and Networking Summer Institute Purpose The Computer System,...

  5. Collaborative project. Ocean-atmosphere interaction from meso-to planetary-scale. Mechanisms, parameterization, and variability

    SciTech Connect (OSTI)

    Small, Richard; Bryan, Frank; Tribbia, Joseph; Park, Sungsu; Dennis, John; Saravanan, R.; Schneider, Niklas; Kwon, Young-Oh

    2015-06-11

    This project aims to improve long term global climate simulations by resolving ocean mesoscale activity and the corresponding response in the atmosphere. The main computational objectives are; i) to perform and assess Community Earth System Model (CESM) simulations with the new Community Atmospheric Model (CAM) spectral element dynamical core; ii) use static mesh refinement to focus on oceanic fronts; iii) develop a new Earth System Modeling tool to investigate the atmospheric response to fronts by selectively filtering surface flux fields in the CESM coupler. The climate research objectives are 1) to improve the coupling of ocean fronts and the atmospheric boundary layer via investigations of dependency on model resolution and stability functions: 2) to understand and simulate the ensuing tropospheric response that has recently been documented in observations: and 3) to investigate the relationship of ocean frontal variability to low frequency climate variability and the accompanying storm tracks and extremes in high resolution simulations. This is a collaborative multi-institution project consisting of computational scientists, climate scientists and climate model developers. It specifically aims at DOE objectives of advancing simulation and predictive capability of climate models through improvements in resolution and physical process representation.

  6. Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar Power

    SciTech Connect (OSTI)

    Mills, Andrew; Wiser, Ryan

    2010-08-23

    Worldwide interest in the deployment of photovoltaic generation (PV) is rapidly increasing. Operating experience with large PV plants, however, demonstrates that large, rapid changes in the output of PV plants are possible. Early studies of PV grid impacts suggested that short-term variability could be a potential limiting factor in deploying PV. Many of these early studies, however, lacked high-quality data from multiple sites to assess the costs and impacts of increasing PV penetration. As is well known for wind, accounting for the potential for geographic diversity can significantly reduce the magnitude of extreme changes in aggregated PV output, the resources required to accommodate that variability, and the potential costs of managing variability. We use measured 1-min solar insolation for 23 time-synchronized sites in the Southern Great Plains network of the Atmospheric Radiation Measurement program and wind speed data from 10 sites in the same network to characterize the variability of PV with different degrees of geographic diversity and to compare the variability of PV to the variability of similarly sited wind. The relative aggregate variability of PV plants sited in a dense 10 x 10 array with 20 km spacing is six times less than the variability of a single site for variability on time scales less than 15-min. We find in our analysis of wind and PV plants similarly sited in a 5 x 5 grid with 50 km spacing that the variability of PV is only slightly more than the variability of wind on time scales of 5-15 min. Over shorter and longer time scales the level of variability is nearly identical. Finally, we use a simple approximation method to estimate the cost of carrying additional reserves to manage sub-hourly variability. We conclude that the costs of managing the short-term variability of PV are dramatically reduced by geographic diversity and are not substantially different from the costs for managing the short-term variability of similarly sited wind in this region.

  7. Constraints on the atmospheric circulation and variability of the eccentric hot Jupiter XO-3b

    SciTech Connect (OSTI)

    Wong, Ian; Knutson, Heather A.; Cowan, Nicolas B.; Lewis, Nikole K.; Agol, Eric; Burrows, Adam; Deming, Drake; Fortney, Jonathan J.; Laughlin, Gregory; Fulton, Benjamin J.; Langton, Jonathan; Showman, Adam P.

    2014-10-20

    We report secondary eclipse photometry of the hot Jupiter XO-3b in the 4.5 ?m band taken with the Infrared Array Camera on the Spitzer Space Telescope. We measure individual eclipse depths and center of eclipse times for a total of 12 secondary eclipses. We fit these data simultaneously with two transits observed in the same band in order to obtain a global best-fit secondary eclipse depth of 0.1580% 0.0036% and a center of eclipse phase of 0.67004 0.00013. We assess the relative magnitude of variations in the dayside brightness of the planet by measuring the size of the residuals during ingress and egress from fitting the combined eclipse light curve with a uniform disk model and place an upper limit of 0.05%. The new secondary eclipse observations extend the total baseline from one and a half years to nearly three years, allowing us to place an upper limit on the periastron precession rate of 2.9 10{sup 3} deg day{sup 1} the tightest constraint to date on the periastron precession rate of a hot Jupiter. We use the new transit observations to calculate improved estimates for the system properties, including an updated orbital ephemeris. We also use the large number of secondary eclipses to obtain the most stringent limits to date on the orbit-to-orbit variability of an eccentric hot Jupiter and demonstrate the consistency of multiple-epoch Spitzer observations.

  8. Control and Size Energy Storage for Managing Energy balance of Variable Generation Resources

    SciTech Connect (OSTI)

    Ke, Xinda; Lu, Ning; Jin, Chunlian

    2015-01-01

    This paper presents control algorithms and sizing strategies for using energy storage to manage energy balance for variable generation resources. The control objective is to minimize the hourly generation imbalance between the actual and the scheduled generation of the wind farm. Three control algorithms are compared: tracking power imbalance, post-compensation, and pre-compensation. Measurement data from a wind farm located in South-central Washington State are used in the study. The results show that tracking power imbalance yields the best performance by keeping the hourly energy imbalances zero. However, the energy storage system (ESS) will be significantly oversized. Post-compensation reduces power rating of the ESS but the hourly imbalance may not be kept as zero when large and long-lasting energy imbalances occur. A linear regression forecasting algorithm is developed for the pre-compensation algorithm to pre-charge or pre-discharge the ESS based on predicted energy imbalances. The performance comparison shows that the pre-compensation method significantly reduces the size of the ESS while maintaining satisfactory performance.

  9. Pressure Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering > Pressure Systems Privacy and Security Notice Skip over navigation Search the JLab Site Pressure Systems Please upgrade your browser. This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to any browser. Concerns? Engineering Division print version Design Authority List Design Authority Toolbox Welding Documentation Pressure Systems Forms PS-1 Pressure System Project Cover Sheet PS-2 Overpressure by System Design

  10. RFQ accelerator tuning system

    DOE Patents [OSTI]

    Bolie, V.W.

    1990-07-03

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations. 3 figs.

  11. RFQ accelerator tuning system

    DOE Patents [OSTI]

    Bolie, Victor W. (Albuquerque, NM)

    1990-01-01

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations.

  12. Empirical Analysis of the Variability of Wind Generation in India: Implications for Grid Integration

    SciTech Connect (OSTI)

    Phadke, Amol; Abhyankar, NIkit; Rao, Poorvi

    2014-06-17

    We analyze variability in load and wind generation in India to assess its implications for grid integration of large scale wind projects using actual wind generation and load data from two states in India, Karnataka and Tamil Nadu. We compare the largest variations in load and net load (load ?wind, i.e., load after integrating wind) that the generation fleet has to meet. In Tamil Nadu, where wind capacity is about 53percent of the peak demand, we find that the additional variation added due to wind over the current variation in load is modest; if wind penetration reaches 15percent and 30percent by energy, the additional hourly variation is less than 0.5percent and 4.5percent of the peak demand respectively for 99percent of the time. For wind penetration of 15percent by energy, Tamil Nadu system is found to be capable of meeting the additional ramping requirement for 98.8percent of the time. Potential higher uncertainty in net load compared to load is found to have limited impact on ramping capability requirements of the system if coal plants can me ramped down to 50percent of their capacity. Load and wind aggregation in Tamil Nadu and Karnataka is found to lower the variation by at least 20percent indicating the benefits geographic diversification. These findings suggest modest additional flexible capacity requirements and costs for absorbing variation in wind power and indicate that the potential capacity support (if wind does not generate enough during peak periods) may be the issue that has more bearing on the economics of integrating wind

  13. VARIABLE FIRING RATE OIL BURNER USING PULSE FUEL FLOW CONTROL.

    SciTech Connect (OSTI)

    KRISHNA,C.R.; BUTCHER,T.A.; KAMATH,B.R.

    2004-10-01

    The residential oil burner market is currently dominated by the pressure-atomized retention head burner, which has an excellent reputation for reliability and efficiency. In this burner, oil is delivered to a fuel nozzle at pressures from 100 to 150 psi. In addition, to atomizing the fuel, the small, carefully controlled size of the nozzle exit orifice serves to control the burner firing rate. Burners of this type are currently available at firing rates of more than 0.5 gallons-per-hour (70,000 Btu/hr). Nozzles have been made for lower firing rates, but experience has shown that such nozzles suffer rapid fouling of the necessarily small passages, leading to bad spray patterns and poor combustion performance. Also, traditionally burners and the nozzles are oversized to exceed the maximum demand. Typically, this is figured as follows. The heating load of the house on the coldest day for the location is considered to define the maximum heat load. The contractor or installer adds to this to provide a safety margin and for future expansion of the house. If the unit is a boiler that provides domestic hot water through the use of a tankless heating coil, the burner capacity is further increased. On the contrary, for a majority of the time, the heating system is satisfying a much smaller load, as only rarely do all these demands add up. Consequently, the average output of the heating system has to be much less than the design capacity and this is accomplished by start and stop cycling operation of the system so that the time-averaged output equals the demand. However, this has been demonstrated to lead to overall efficiencies lower than the steady-state efficiency. Therefore, the two main reasons for the current practice of using oil burners much larger than necessary for space heating are the unavailability of reliable low firing rate oil burners and the desire to assure adequate input rate for short duration, high draw domestic hot water loads. One approach to solve this problem is to develop a burner, which can operate at two firing rates, with the lower rate being significantly lower than 0.5 gallons per hour. This paper describes the initial results of adopting this approach through a pulsed flow nozzle. It has been shown that the concept of flow modulation with a small solenoid valve is feasible. Especially in the second configuration tested, where the Lee valve was integrated with the nozzle, reasonable modulation in flow of the order of 1.7 could be achieved. For this first prototype, the combustion performance is still not quite satisfactory. Improvements in operation, for example by providing a sharp and positive shut-off so that there is no flow under low pressures with consequent poor atomization could lead to better combustion performance. This could be achieved by using nozzles that have shut off or check valves for example. It is recommended that more work in cooperation with the valve manufacturer could produce a technically viable system. Marketability is of course a far more complex problem to be addressed once a technically viable product is available.

  14. Amplitude Variability in gamma Dor and delta Sct Stars Observed by Kepler

    SciTech Connect (OSTI)

    Guzik, Joyce Ann; Kosak, Mary Katherine; Bradley, Paul Andrew; Jackiewicz, Jason

    2015-08-17

    The NASA Kepler spacecraft data revealed a large number of new multimode nonradially pulsating gamma Dor and delta Sct variable stars. The Kepler high-precision long time-series photometry makes it possible to study amplitude variations of the frequencies, and recent literature on amplitude and frequency variations in nonradially pulsating variables is summarized. Several methods are applied to study amplitude variability in about a dozen gamma Doradus or delta Scuti candidate variable stars observed for several quarters as part of the Kepler Guest Observer program. The magnitude and timescale of the amplitude variations are discussed, along with the presence or absence of correlations between amplitude variations for different frequencies of a given star. Proposed causes of amplitude spectrum variability that will require further investigation are also discussed.

  15. Harmonic analysis of electrical distribution systems

    SciTech Connect (OSTI)

    1996-03-01

    This report presents data pertaining to research on harmonics of electric power distribution systems. Harmonic data is presented on RMS and average measurements for determination of harmonics in buildings; fluorescent ballast; variable frequency drive; georator geosine harmonic data; uninterruptible power supply; delta-wye transformer; westinghouse suresine; liebert datawave; and active injection mode filter data.

  16. File Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    File Systems File Systems For a general description of the different file systems available on PDSF please see Eliza File Systems and Other File Systems. Below is a summary of how ALICE uses the various systems: /common ALICE uses /common to build the software that supports its grid-based automated production work. This software includes AliRoot, Geant, AliEn, and XRootD. /eliza6, /eliza8, /eliza17 ALICE has space on 3 elizas: 16TB on /eliza6, 6TB on /eliza8 and 11TB on /eliza17. The space on

  17. File Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    File Systems File Systems For a general description of the different file systems available on PDSF please see Eliza File Systems and Other File Systems. Below is a summary of how STAR uses the various systems: /common The STAR software is installed on /common. For 32sl44 it is under /common/star/star44 and for sl53 it is under /common/star/star53. In both cases the software consists primarily of a STAR-specific ROOT installation on which releases of the STAR libraries are built as shown on the

  18. Files systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Files systems Files systems NERSC's global home and project file systems are available on Franklin. Additionally, Franklin has over 400 TB of locally attached high-performance /scratch disk space For information on the NERSC file systems, see the link at right. Scratch File Systems Size Aggregate Peak Performance # IO Servers Interconnect File System Software Disk Array Vendor $SCRATCH 209 TB 17 GB/sec 24 Lustre DDN $SCRATCH2 209 TB 17 GB/sec 24 Lustre DDN SCRATCH and SCRATCH2 There are two

  19. The Basis Code Development System

    Energy Science and Technology Software Center (OSTI)

    1994-03-15

    BASIS9.4 is a system for developing interactive computer programs in Fortran, with some support for C and C++ as well. Using BASIS9.4 you can create a program that has a sophisticated programming language as its user interface so that the user can set, calculate with, and plot, all the major variables in the program. The program author writes only the scientific part of the program; BASIS9.4 supplies an environment in which to exercise that scientificmore » programming which includes an interactive language, an interpreter, graphics, terminal logs, error recovery, macros, saving and retrieving variables, formatted I/O, and online documentation.« less

  20. Evaluation of Retrofit Variable-Speed Furnace Fan Motors

    SciTech Connect (OSTI)

    Aldrich, R.; Williamson, J.

    2014-01-01

    In conjunction with the New York State Energy Research and Development Authority (NYSERDA) and Proctor Engineering Group, Ltd. (PEG), the Consortium for Advanced Residential Buildings (CARB) has evaluated the Concept 3 replacement motors for residential furnaces. These brushless, permanent magnet (BPM) motors can use much less electricity than their PSC (permanent split capacitor) predecessors. This evaluation focuses on existing homes in the heating-dominated climate of upstate New York with the goals of characterizing field performance and cost effectiveness. The project includes eight homes in and near Syracuse, NY. Tests and monitoring was performed both before and after fan motors were replaced. Results indicate that BPM replacement motors will be most cost effective in HVAC systems with longer run times and relatively low duct static pressures. More dramatic savings are possible if occupants use the fan-only setting when there is no thermal load. There are millions of cold-climate, U.S. homes that meet these criteria, but the savings in most homes tested in this study were modest.

  1. BONA FIDE, STRONG-VARIABLE GALACTIC LUMINOUS BLUE VARIABLE STARS ARE FAST ROTATORS: DETECTION OF A HIGH ROTATIONAL VELOCITY IN HR CARINAE

    SciTech Connect (OSTI)

    Groh, J. H.; Damineli, A.; Moises, A. P.; Teodoro, M.; Hillier, D. J.; Barba, R.; Fernandez-Lajus, E.; Gamen, R. C.; Solivella, G.

    2009-11-01

    We report optical observations of the luminous blue variable (LBV) HR Carinae which show that the star has reached a visual minimum phase in 2009. More importantly, we detected absorptions due to Si IV lambdalambda4088-4116. To match their observed line profiles from 2009 May, a high rotational velocity of v{sub rot} approx = 150 +- 20 km s{sup -1} is needed (assuming an inclination angle of 30 deg.), implying that HR Car rotates at approx =0.88 +- 0.2 of its critical velocity for breakup (v{sub crit}). Our results suggest that fast rotation is typical in all strong-variable, bona fide galactic LBVs, which present S-Dor-type variability. Strong-variable LBVs are located in a well-defined region of the HR diagram during visual minimum (the 'LBV minimum instability strip'). We suggest this region corresponds to where v{sub crit} is reached. To the left of this strip, a forbidden zone with v{sub rot}/v{sub crit}>1 is present, explaining why no LBVs are detected in this zone. Since dormant/ex LBVs like P Cygni and HD 168625 have low v{sub rot}, we propose that LBVs can be separated into two groups: fast-rotating, strong-variable stars showing S-Dor cycles (such as AG Car and HR Car) and slow-rotating stars with much less variability (such as P Cygni and HD 168625). We speculate that supernova (SN) progenitors which had S-Dor cycles before exploding (such as in SN 2001ig, SN 2003bg, and SN 2005gj) could have been fast rotators. We suggest that the potential difficulty of fast-rotating Galactic LBVs to lose angular momentum is additional evidence that such stars could explode during the LBV phase.

  2. Deconvolving X-ray spectral variability components in the Seyfert 1.5 NGC 3227

    SciTech Connect (OSTI)

    Arvalo, P.; Markowitz, A.

    2014-03-10

    We present the variability analysis of a 100 ks XMM-Newton observation of the Seyfert 1.5 active galaxy, NGC 3227. The observation found NGC 3227 in a period where its hard power-law component displayed remarkably little long-term variability. This lucky event allows us to clearly observe a soft spectral component undergoing a large-amplitude but slow flux variation. Using combined spectral and timing analysis, we isolate two independent variable continuum components and characterize their behavior as a function of timescale. Rapid and coherent variations throughout the 0.2-10 keV band reveal a spectrally hard (photon index ? ? 1.7-1.8) power law, dominating the observed variability on timescales of 30 ks and shorter. Another component produces coherent fluctuations in the 0.2-2 keV range and is much softer (? ? 3); it dominates the observed variability on timescales greater than 30 ks. Both components are viewed through the same absorbers identified in the time-averaged spectrum. The combined spectral and timing analysis breaks the degeneracy between models for the soft excess: it is consistent with a power-law or thermal Comptonized component but not with a blackbody or an ionized reflection component. We demonstrate that the rapid variability in NGC 3227 is intrinsic to continuum-emitting components and is not an effect of variable absorption.

  3. Evaluation of Retrofit Variable-Speed Furnace Fan Motors

    SciTech Connect (OSTI)

    Aldrich, R.; Williamson, J.

    2014-01-01

    In conjunction with the New York State Energy Research and Development Authority (NYSERDA) and Proctor Engineering Group, Ltd. (PEG), the Consortium for Advanced Residential Buildings (CARB) has evaluated the Concept 3 (tm) replacement motors for residential furnaces. These brushless, permanent magnet (BPM) motors can use much less electricity than their PSC (permanent split capacitor) predecessors. This evaluation focuses on existing homes in the heating-dominated climate of upstate New York with the goals of characterizing field performance and cost-effectiveness. The results of this study are intended to be useful to home performance contractors, HVAC contractors, and home efficiency program stakeholders. The project includes eight homes in and near Syracuse, NY. Tests and monitoring was performed both before and after fan motors were replaced. Average fan power reductions were approximately 126 Watts during heating and 220 Watts during cooling operation. Over the course of entire heating and cooling seasons, these translated into average electric energy savings of 163 kWh. Average cost savings were $20 per year. Homes where the fan was used outside of heating and cooling mode saved an additional $42 per year on average. Results indicate that BPM replacement motors will be most cost-effective in HVAC systems with longer run times and relatively low duct static pressures. More dramatic savings are possible if occupants use the fan-only setting when there is no thermal load. There are millions of cold-climate, U.S. homes that meet these criteria, but the savings in most homes tested in this study were modest.

  4. ATMOSPHERIC CIRCULATION OF BROWN DWARFS: JETS, VORTICES, AND TIME VARIABILITY

    SciTech Connect (OSTI)

    Zhang, Xi; Showman, Adam P.

    2014-06-10

    A variety of observational evidence demonstrates that brown dwarfs exhibit active atmospheric circulations. In this study we use a shallow-water model to investigate the global atmospheric dynamics in the stratified layer overlying the convective zone on these rapidly rotating objects. We show that the existence and properties of the atmospheric circulation crucially depend on key parameters including the energy injection rate and radiative timescale. Under conditions of strong internal heat flux and weak radiative dissipation, a banded flow pattern comprised of east-west jet streams spontaneously emerges from the interaction of atmospheric turbulence with the planetary rotation. In contrast, when the internal heat flux is weak and/or radiative dissipation is strong, turbulence injected into the atmosphere damps before it can self-organize into jets, leading to a flow dominated by transient eddies and isotropic turbulence instead. The simulation results are not very sensitive to the form of the forcing. Based on the location of the transition between jet-dominated and eddy-dominated regimes, we suggest that many brown dwarfs may exhibit atmospheric circulations dominated by eddies and turbulence (rather than jets) due to the strong radiative damping on these worlds, but a jet structure is also possible under some realistic conditions. Our simulated light curves capture important features from observed infrared light curves of brown dwarfs, including amplitude variations of a few percent and shapes that fluctuate between single-peak and multi-peak structures. More broadly, our work shows that the shallow-water system provides a useful tool to illuminate fundamental aspects of the dynamics on these worlds.

  5. Projected Changes in Mean and Interannual Variability of Surface Water over Continental China

    SciTech Connect (OSTI)

    Leng, Guoyong; Tang, Qiuhong; Huang, Maoyi; Hong, Yang; Leung, Lai-Yung R.

    2015-05-01

    Five General Circulation Model (GCM) climate projections under the RCP8.5 emission scenario were used to drive the Variable Infiltration Capacity (VIC) hydrologic model to investigate the impacts of climate change on hydrologic cycle over continental China in the 21st century. The bias-corrected climatic variables were generated for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5) by the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP). Results showed much larger fractional changes of annual mean Evaportranspiration (ET) per unit warming than the corresponding fractional changes of Precipitation (P) per unit warming across the country especially for South China, which led to notable decrease of surface water variability (P-E). Specifically, negative trends for annual mean runoff up to -0.33%/decade and soil moisture trends varying between -0.02 to -0.13%/decade were found for most river basins across China. Coincidentally, interannual variability for both runoff and soil moisture exhibited significant positive trends for almost all river basins across China, implying an increase in extremes relative to the mean conditions. Noticeably, the largest positive trends for runoff variability and soil moisture variability, which were up to 38 0.41%/decade and 0.90%/decade, both occurred in Southwest China. In addition to the regional contrast, intra-seasonal variation was also large for the runoff mean and runoff variability changes, but small for the soil moisture mean and variability changes. Our results suggest that future climate change could further exacerbate existing water-related risks (e.g. floods and droughts) across China as indicated by the marked decrease of surface water amounts combined with steady increase of interannual variability throughout the 21st century. This study highlights the regional contrast and intra-seasonal variations for the projected hydrologic changes and could provide muti-scale guidance for assessing effective adaptation strategies for the country on a river basin, regional, or as whole.

  6. Collaborative project. Ocean-atmosphere interaction from meso- to planetary-scale. Mechanics, parameterization, and variability

    SciTech Connect (OSTI)

    Saravanan, Ramalingam; Small, Justin

    2015-12-01

    Most climate models are currently run with grid spacings of around 100km, which, with today’s computing power, allows for long (up to 1000 year) simulations, or ensembles of simulations to explore climate change and variability. However this grid spacing does not resolve important components of the weather/climate system such as atmospheric fronts and mesoscale systems, and ocean boundary currents and eddies. The overall aim of this project has been to look at the effect of these small-scale features on the weather/climate system using a suite of high and low resolution climate models, idealized models and observations. High-resolution global coupled integrations using CAM/CESM were carried out at NCAR by the lead PI. At TAMU, we have complemented the work at NCAR by analyzing datasets from the high-resolution (28km) CESM integrations (Small et al., 2014) as well as very high resolution (9km, 3km) runs using a coupled regional climate (CRCM) carried out locally. The main tasks carried out were: 1. Analysis of surface wind in observations and high-resolution CAM/CCSM simulations 2. Development of a feature-tracking algorithm for studying midlatitude air-sea interaction by following oceanic mesoscale eddies and creating composites of the atmospheric response overlying the eddies. 3. Applying the Lagrangian analysis technique in the Gulf Stream region to compare data from observational reanalyses, global CESM coupled simulations, 9km regional coupled simulations and 3km convection-resolving regional coupled simulations. Our main findings are that oceanic mesoscale eddies influence not just the atmospheric boundary layer above them, but also the lower portions of the free troposphere above the boundary layer. Such a vertical response could have implications for a remote influence of Gulf Stream oceanic eddies on North Atlantic weather patterns through modulation of the storm track, similar to what has been noted in the North Pacific. The coarse resolution observational reanalyses perhaps underestimate the atmospheric response, but the 28km global model resolution appears to be adequate to capture some, but not all, aspects of the boundary response. The higher resolution regional models show a stronger response in certain fields such as the latent heat flux.

  7. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    SciTech Connect (OSTI)

    Eto, Joseph H.; Undrill, John; Mackin, Peter; Daschmans, Ron; Williams, Ben; Haney, Brian; Hunt, Randall; Ellis, Jeff; Illian, Howard; Martinez, Carlos; O'Malley, Mark; Coughlin, Katie; LaCommare, Kristina Hamachi

    2010-12-20

    An interconnected electric power system is a complex system that must be operated within a safe frequency range in order to reliably maintain the instantaneous balance between generation and load. This is accomplished by ensuring that adequate resources are available to respond to expected and unexpected imbalances and restoring frequency to its scheduled value in order to ensure uninterrupted electric service to customers. Electrical systems must be flexible enough to reliably operate under a variety of"change" scenarios. System planners and operators must understand how other parts of the system change in response to the initial change, and need tools to manage such changes to ensure reliable operation within the scheduled frequency range. This report presents a systematic approach to identifying metrics that are useful for operating and planning a reliable system with increased amounts of variable renewable generation which builds on existing industry practices for frequency control after unexpected loss of a large amount of generation. The report introduces a set of metrics or tools for measuring the adequacy of frequency response within an interconnection. Based on the concept of the frequency nadir, these metrics take advantage of new information gathering and processing capabilities that system operators are developing for wide-area situational awareness. Primary frequency response is the leading metric that will be used by this report to assess the adequacy of primary frequency control reserves necessary to ensure reliable operation. It measures what is needed to arrest frequency decline (i.e., to establish frequency nadir) at a frequency higher than the highest set point for under-frequency load shedding within an interconnection. These metrics can be used to guide the reliable operation of an interconnection under changing circumstances.

  8. Near-IR spectroscopic monitoring of CLASS I protostars: Variability of accretion and wind indicators

    SciTech Connect (OSTI)

    Connelley, Michael S.; Greene, Thomas P.

    2014-06-01

    We present the results of a program that monitored the near-IR spectroscopic variability of a sample of 19 embedded protostars. Spectra were taken on time intervals from 2 days to 3 yr, over a wavelength range from 0.85 ?m to 2.45 ?m, for 4-9 epochs of observations per target. We found that the spectra of all targets are variable and that every emission feature observed is also variable (although not for all targets). With one exception, there were no drastic changes in the continua of the spectra, nor did any line completely disappear, nor did any line appear that was not previously apparent. This analysis focuses on understanding the connection between accretion (traced by H Br ? and CO) and the wind (traced by He I, [Fe II], and sometimes H{sub 2}). For both accretion and wind tracers, the median variability was constant versus the time interval between observations; however, the maximum variability that we observed increased with the time interval between observations. Extinction is observed to vary within the minimum sampling time of 2 days, suggesting extinguishing material within a few stellar radii at high disk latitudes. The variability of [Fe II] and H{sub 2} were correlated for most (but not all) of the 7 young stellar objects showing both features, and the amplitude of the variability depends on the veiling. Although the occurrence of CO and Br ? emission are connected, their variability is uncorrelated, suggesting that these emissions originate in separate regions near the protostar (e.g., disk and wind). The variability of Br ? and wind tracers were found to be positively correlated, negatively correlated, or uncorrelated, depending on the target. The variability of Br ?, [Fe II], and H{sub 2} always lies on a plane, although the orientation of the plane in three dimensions depends on the target. While we do not understand all interactions behind the variability that we observed, we have shown that spectroscopic variability is a powerful tool toward understanding the star formation process.

  9. Wave-induced pore pressure and effective stresses in a porous seabed with variable permeability

    SciTech Connect (OSTI)

    Jeng, D.S.; Seymour, B.R.

    1996-12-31

    An evaluation of wave-induced soil response is particularly useful for geotechnical and coastal engineers involved in the design of foundations for offshore structures. To simplify the mathematical procedure, most theories available for the wave/seabed interaction problem have assumed a porous seabed with uniform permeability, despite strong evidence of variable permeability. This paper proposes an analytical solution for the wave induced soil response in a porous seabed with variable permeability. Verification is available through reduction to the simple case of uniform permeability. The numerical results indicate that the effect of variable soil permeability on pore pressure and effective stresses is significant.

  10. System Effectiveness

    SciTech Connect (OSTI)

    Powell, Danny H; Elwood Jr, Robert H

    2011-01-01

    An effective risk assessment system is needed to address the threat posed by an active or passive insider who, acting alone or in collusion, could attempt diversion or theft of nuclear material. It is critical that a nuclear facility conduct a thorough self-assessment of the material protection, control, and accountability (MPC&A) system to evaluate system effectiveness. Self-assessment involves vulnerability analysis and performance testing of the MPC&A system. The process should lead to confirmation that mitigating features of the system effectively minimize the threat, or it could lead to the conclusion that system improvements or upgrades are necessary to achieve acceptable protection against the threat. Analysis of the MPC&A system is necessary to understand the limits and vulnerabilities of the system to internal threats. Self-assessment helps the facility be prepared to respond to internal threats and reduce the risk of theft or diversion of nuclear material. MSET is a self-assessment or inspection tool utilizing probabilistic risk assessment (PRA) methodology to calculate the system effectiveness of a nuclear facility's MPC&A system. MSET analyzes the effectiveness of an MPC&A system based on defined performance metrics for MPC&A functions based on U.S. and international best practices and regulations. A facility's MC&A system can be evaluated at a point in time and reevaluated after upgrades are implemented or after other system changes occur. The total system or specific subareas within the system can be evaluated. Areas of potential performance improvement or system upgrade can be assessed to determine where the most beneficial and cost-effective improvements should be made. Analyses of risk importance factors show that sustainability is essential for optimal performance. The analyses reveal where performance degradation has the greatest detrimental impact on total system risk and where performance improvements have the greatest reduction in system risk. The risk importance factors show the amount of risk reduction achievable with potential upgrades and the amount of risk reduction actually achieved after upgrades are completed. Applying the risk assessment tool gives support to budget prioritization by showing where budget support levels must be sustained for MC&A functions most important to risk. Results of the risk assessment are also useful in supporting funding justifications for system improvements that significantly reduce system risk.

  11. Case Study - The Challenge: Improving Ventilation System Energy Efficiency

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in a Textile Plant | Department of Energy Ventilation System Energy Efficiency in a Textile Plant Case Study - The Challenge: Improving Ventilation System Energy Efficiency in a Textile Plant This case study examines how Nisshinbo California, Inc. (NCI) worked with ADI Control Techniques Drives (ADI-CT) of Hayward, California, to improve ventilation system performance in its Fresno, California, textile plant. The company retrofitted 15 of the system's fan motors with variable frequency

  12. Chapter 3 - Enabling Modernization of the Electric Power System |

    Office of Environmental Management (EM)

    Department of Energy 3 - Enabling Modernization of the Electric Power System Chapter 3 - Enabling Modernization of the Electric Power System Chapter 3 - Enabling Modernization of the Electric Power System The electric power system is facing increasing stress due to fundamental changes in both supply and demand technologies. On the supply side, there is a shift from large synchronous generators to lighter-weight generators (e.g., gas-fired turbines) and variable resources (renewables). On the

  13. Twisted MoSe2 bilayers with variable local stacking and interlayer coupling revealed by low-frequency Raman spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Puretzky, Alexander A.; Liang, Liangbo; Li, Xufan; Xiao, Kai; Sumpter, Bobby G.; Meunier, Vincent; Geohegan, David B.

    2016-01-14

    Unique twisted bilayers of MoSe2 with multiple stacking orientations and interlayer couplings in the narrow range of twist angles, 60 ± 3°, are revealed by low-frequency Raman spectroscopy and theoretical analysis. The slight deviation from 60 allows the concomitant presence of patches featuring all three high-symmetry stacking configurations (2H or AA', AB', A'B) in one unique bilayer system. In this case, the periodic arrangement of the patches and their size strongly depend on the twist angle. Ab initio modeling predicts significant changes in frequencies and intensities of low-frequency modes versus stacking and twist angle. Experimentally, the variable stacking and couplingmore » across the interface is revealed by the appearance of two breathing modes corresponding to the mixture of the high-symmetry stacking configurations and unaligned regions of monolayers. Only one breathing mode is observed outside the narrow range of twist angles. This indicates a stacking transition to unaligned monolayers with mismatched atom registry without the in-plane restoring force required to generate a shear mode. As a result, the variable interlayer coupling and spacing in transition metal dichalcogenide bilayers revealed in this study may provide a new platform for optoelectronic applications of these materials.« less

  14. Air ejector augmented compressed air energy storage system

    DOE Patents [OSTI]

    Ahrens, F.W.; Kartsounes, G.T.

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air presure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  15. Air ejector augmented compressed air energy storage system

    DOE Patents [OSTI]

    Ahrens, Frederick W.; Kartsounes, George T.

    1980-01-01

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air pressure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  16. Magnus air turbine system

    DOE Patents [OSTI]

    Hanson, Thomas F. (24204 Heritage La., Newhall, CA 91321)

    1982-01-01

    A Magnus effect windmill for generating electrical power is disclosed. A large nacelle-hub mounted pivotally (in Azimuth) atop a support tower carries, in the example disclosed, three elongated barrels arranged in a vertical plane and extending symmetrically radially outwardly from the nacelle. The system provides spin energy to the barrels by internal mechanical coupling in the proper sense to cause, in reaction to an incident wind, a rotational torque of a predetermined sense on the hub. The rotating hub carries a set of power take-off rollers which ride on a stationary circular track in the nacelle. Shafts carry the power, given to the rollers by the wind driven hub, to a central collector or accumulator gear assembly whose output is divided to drive the spin mechanism for the Magnus barrels and the main electric generator. A planetary gear assembly is interposed between the collector gears and the spin mechanism functioning as a differential which is also connected to an auxiliary electric motor whereby power to the spin mechanism may selectively be provided by the motor. Generally, the motor provides initial spin to the barrels for start-up after which the motor is braked and the spin mechanism is driven as though by a fixed ratio coupling from the rotor hub. During high wind or other unusual conditions, the auxiliary motor may be unbraked and excess spin power may be used to operate the motor as a generator of additional electrical output. Interposed between the collector gears of the rotating hub and the main electric generator is a novel variable speed drive-fly wheel system which is driven by the variable speed of the wind driven rotor and which, in turn, drives the main electric generator at constant angular speed. Reference is made to the complete specification for disclosure of other novel aspects of the system such as, for example, the aerodynamic and structural aspects of the novel Magnus barrels as well as novel gearing and other power coupling combination apparatus of the invention. A reading of the complete specification is recommended for a full understanding of the principles and features of the disclosed system.

  17. SU-E-T-539: Fixed Versus Variable Optimization Points in Combined-Mode Modulated Arc Therapy Planning

    SciTech Connect (OSTI)

    Kainz, K; Prah, D; Ahunbay, E; Li, X

    2014-06-01

    Purpose: A novel modulated arc therapy technique, mARC, enables superposition of step-and-shoot IMRT segments upon a subset of the optimization points (OPs) of a continuous-arc delivery. We compare two approaches to mARC planning: one with the number of OPs fixed throughout optimization, and another where the planning system determines the number of OPs in the final plan, subject to an upper limit defined at the outset. Methods: Fixed-OP mARC planning was performed for representative cases using Panther v. 5.01 (Prowess, Inc.), while variable-OP mARC planning used Monaco v. 5.00 (Elekta, Inc.). All Monaco planning used an upper limit of 91 OPs; those OPs with minimal MU were removed during optimization. Plans were delivered, and delivery times recorded, on a Siemens Artiste accelerator using a flat 6MV beam with 300 MU/min rate. Dose distributions measured using ArcCheck (Sun Nuclear Corporation, Inc.) were compared with the plan calculation; the two were deemed consistent if they agreed to within 3.5% in absolute dose and 3.5 mm in distance-to-agreement among > 95% of the diodes within the direct beam. Results: Example cases included a prostate and a head-and-neck planned with a single arc and fraction doses of 1.8 and 2.0 Gy, respectively. Aside from slightly more uniform target dose for the variable-OP plans, the DVHs for the two techniques were similar. For the fixed-OP technique, the number of OPs was 38 and 39, and the delivery time was 228 and 259 seconds, respectively, for the prostate and head-and-neck cases. For the final variable-OP plans, there were 91 and 85 OPs, and the delivery time was 296 and 440 seconds, correspondingly longer than for fixed-OP. Conclusion: For mARC, both the fixed-OP and variable-OP approaches produced comparable-quality plans whose delivery was successfully verified. To keep delivery time per fraction short, a fixed-OP planning approach is preferred.

  18. HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR...

    Office of Scientific and Technical Information (OSTI)

    The time domain is just beginning to be explored over large sky areas; we do not know exactly what a violently variable sample will hold. About 20% of the sample has been ...

  19. Final Technical Report: Low-Cost Solar Variability Sensors for Ubiquitous Deployment.

    SciTech Connect (OSTI)

    Lave, Matthew Samuel

    2016-01-01

    In this project, an integrated solution to measuring and collecting solar variability data called the solar variability datalogger (SVD) was developed, tested, and the value of its data to distribution grid integration studies was demonstrated. This work addressed the problem that high-frequency solar variability is rarely measured – due to the high cost and complex installation of existing solar irradiance measuring pyranometers – but is critical to the accurate determination of the impact of photovoltaics to electric grid operation. For example, up to a 300% difference in distribution grid voltage regulator tap change operations (a measure of the impact of PV) [1] has been observed due solely to different solar variability profiles.

  20. Strategies for Mitigating the Reduction in Economic Value of Variable Generation with Increasing Penetration Levels

    SciTech Connect (OSTI)

    Mills, Andrew; Wiser, Ryan

    2014-03-03

    In this report, we evaluate individual options that have the potential to stem the decline in the marginal value of variable generation (VG) with increasing penetration levels. We focus only on the effectiveness of mitigation measures for wind and PV.

  1. Variability of Power from Large-Scale Solar Photovoltaic Scenarios in the State of Gujarat: Preprint

    SciTech Connect (OSTI)

    Parsons, B.; Hummon, M.; Cochran, J.; Stoltenberg, B.; Batra, P.; Mehta, B.; Patel, D.

    2014-04-01

    India has ambitious goals for high utilization of variable renewable power from wind and solar, and deployment has been proceeding at a rapid pace. The western state of Gujarat currently has the largest amount of solar generation of any Indian state, with over 855 Megawatts direct current (MWDC). Combined with over 3,240 MW of wind, variable generation renewables comprise nearly 18% of the electric-generating capacity in the state. A new historic 10-kilometer (km) gridded solar radiation data set capturing hourly insolation values for 2002-2011 is available for India. We apply an established method for downscaling hourly irradiance data to one-minute irradiance data at potential PV power production locations for one year, 2006. The objective of this report is to characterize the intra-hour variability of existing and planned photovoltaic solar power generation in the state of Gujarat (a total of 1.9 gigawatts direct current (GWDC)), and of five possible expansion scenarios of solar generation that reflect a range of geographic diversity (each scenario totals 500-1,000 MW of additional solar capacity). The report statistically analyzes one year's worth of power variability data, applied to both the baseline and expansion scenarios, to evaluate diurnal and seasonal power fluctuations, different timescales of variability (e.g., from one to 15 minutes), the magnitude of variability (both total megawatts and relative to installed solar capacity), and the extent to which the variability can be anticipated in advance. The paper also examines how Gujarat Energy Transmission Corporation (GETCO) and the Gujarat State Load Dispatch Centre (SLDC) could make use of the solar variability profiles in grid operations and planning.

  2. Variability of Power from Large-Scale Solar Photovoltaic Scenarios in the State of Gujarat (Presentation)

    SciTech Connect (OSTI)

    Parsons, B.; Hummon, M.; Cochran, J.; Stoltenberg, B.; Batra, P.; Mehta, B.; Patel, D.

    2014-04-01

    India has ambitious goals for high utilization of variable renewable power from wind and solar, and deployment has been proceeding at a rapid pace. The western state of Gujarat currently has the largest amount of solar generation of any Indian state, with over 855 Megawatts direct current (MWDC). Combined with over 3,240 MW of wind, variable generation renewables comprise nearly 18% of the electric-generating capacity in the state. A new historic 10-kilometer (km) gridded solar radiation data set capturing hourly insolation values for 2002-2011 is available for India. We apply an established method for downscaling hourly irradiance data to one-minute irradiance data at potential PV power production locations for one year, 2006. The objective of this report is to characterize the intra-hour variability of existing and planned photovoltaic solar power generation in the state of Gujarat (a total of 1.9 gigawatts direct current (GWDC)), and of five possible expansion scenarios of solar generation that reflect a range of geographic diversity (each scenario totals 500-1,000 MW of additional solar capacity). The report statistically analyzes one year's worth of power variability data, applied to both the baseline and expansion scenarios, to evaluate diurnal and seasonal power fluctuations, different timescales of variability (e.g., from one to 15 minutes), the magnitude of variability (both total megawatts and relative to installed solar capacity), and the extent to which the variability can be anticipated in advance. The paper also examines how Gujarat Energy Transmission Corporation (GETCO) and the Gujarat State Load Dispatch Centre (SLDC) could make use of the solar variability profiles in grid operations and planning.

  3. The Effect of Precipitation on Variability of Low Stratiform Clouds Over ARM SGP Site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Precipitation on Variability of Low Stratiform Clouds Over ARM SGP Site Z. N. Kogan, D. B. Mechem, and Y. L. Kogan Cooperative Institute for Mesoscale Metorological Studies University of Oklahoma Norman, Oklahoma Introduction Continental low stratiform clouds cover the sky about 23% of the time during the fall, winter, and spring months and play a significant role in the Earth' radiation budget. Information about cloud structure and variability is crucial in determining areal averages of cloud

  4. Impact of Real Field Diesel Quality Variability on Engine Emissions and

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Fuel Consumption Solutions for Onboard Optimisation | Department of Energy Real Field Diesel Quality Variability on Engine Emissions and Fuel Consumption Solutions for Onboard Optimisation Impact of Real Field Diesel Quality Variability on Engine Emissions and Fuel Consumption Solutions for Onboard Optimisation A matrix of 10 diesel fuels was prepared and tested to establish an optimized ECU setting and a compensating algorithm for the engine. PDF icon p-07_hermitte.pdf More Documents &

  5. Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Clean Diesels | Department of Energy Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels Poster presentation from the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007, Detroit, Michigan. Sponsored by the U.S. Department of Energy's (DOE) Office of FreedomCAR and Vehicle Technologies (OFCVT). PDF icon deer07_hou.pdf More

  6. Variability of Photovoltaic Power in the State of Gujarat Using High Resolution Solar Data

    SciTech Connect (OSTI)

    Hummon, M.; Cochran, J.; Weekley, A.; Lopez, A.; Zhang, J.; Stoltenberg, B.; Parsons, B.; Batra, P.; Mehta, B.; Patel, D.

    2014-03-01

    India has ambitious goals for high utilization of variable renewable power from wind and solar, and deployment has been proceeding at a rapid pace. The western state of Gujarat currently has the largest amount of solar generation of any Indian state, with over 855 Megawatts direct current (MWDC). Combined with over 3,240 MW of wind, variable generation renewables comprise nearly 18% of the electric-generating capacity in the state. A new historic 10-kilometer (km) gridded solar radiation data set capturing hourly insolation values for 2002-2011 is available for India. We apply an established method for downscaling hourly irradiance data to one-minute irradiance data at potential PV power production locations for one year, 2006. The objective of this report is to characterize the intra-hour variability of existing and planned photovoltaic solar power generation in the state of Gujarat (a total of 1.9 gigawatts direct current (GWDC)), and of five possible expansion scenarios of solar generation that reflect a range of geographic diversity (each scenario totals 500-1,000 MW of additional solar capacity). The report statistically analyzes one year's worth of power variability data, applied to both the baseline and expansion scenarios, to evaluate diurnal and seasonal power fluctuations, different timescales of variability (e.g., from one to 15 minutes), the magnitude of variability (both total megawatts and relative to installed solar capacity), and the extent to which the variability can be anticipated in advance. The paper also examines how Gujarat Energy Transmission Corporation (GETCO) and the Gujarat State Load Dispatch Centre (SLDC) could make use of the solar variability profiles in grid operations and planning.

  7. Refrigeration system having standing wave compressor

    DOE Patents [OSTI]

    Lucas, Timothy S. (Glen Allen, VA)

    1992-01-01

    A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

  8. Combustion pinhole-camera system

    DOE Patents [OSTI]

    Witte, A.B.

    1982-05-19

    A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

  9. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations

    SciTech Connect (OSTI)

    Jones, Lawrence E.

    2011-11-01

    This report provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  10. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations. Executive Summary

    SciTech Connect (OSTI)

    Jones, Lawrence E.

    2011-11-01

    This is the executive summary for a report that provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  11. CHARACTERIZATION OF A RIGID BARRIER FILTER SYSTEM

    SciTech Connect (OSTI)

    Chiang, Ta-Kuan

    2001-11-06

    A mathematical model is formulated to describe the dynamics of a rigid barrier filter system. Complete with filtration, regeneration and particle re-deposition, this model provides sizing information for new filter systems and diagnostic information for operating filter systems. To turn this model into a practical and smart filter system predictive model, monitoring devices for variables such as real-time particle concentration and size distribution are currently under laboratory development. The program goal is to introduce a smart filter system to supervise its operation and to assure its system reliability. Primarily, a smart filter system will update operating information, sound up malfunction alarms, and provide self-activated measures such as adjusting the cleaning frequency, intensity and back-pulse duration.

  12. Pulsed helium ionization detection system

    DOE Patents [OSTI]

    Ramsey, R.S.; Todd, R.A.

    1985-04-09

    A helium ionization detection system is provided which produces stable operation of a conventional helium ionization detector while providing improved sensitivity and linearity. Stability is improved by applying pulsed dc supply voltage across the ionization detector, thereby modifying the sampling of the detectors output current. A unique pulse generator is used to supply pulsed dc to the detector which has variable width and interval adjust features that allows up to 500 V to be applied in pulse widths ranging from about 150 nsec to about dc conditions.

  13. Pulsed helium ionization detection system

    DOE Patents [OSTI]

    Ramsey, Roswitha S. (Knoxville, TN); Todd, Richard A. (Knoxville, TN)

    1987-01-01

    A helium ionization detection system is provided which produces stable operation of a conventional helium ionization detector while providing improved sensitivity and linearity. Stability is improved by applying pulsed dc supply voltage across the ionization detector, thereby modifying the sampling of the detectors output current. A unique pulse generator is used to supply pulsed dc to the detector which has variable width and interval adjust features that allows up to 500 V to be applied in pulse widths ranging from about 150 nsec to about dc conditions.

  14. Power system

    DOE Patents [OSTI]

    Hickam, Christopher Dale (Glasford, IL)

    2008-03-18

    A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

  15. A search for optical variability of type 2 quasars in SDSS stripe 82

    SciTech Connect (OSTI)

    Barth, Aaron J.; Carson, Daniel J.; Voevodkin, Alexey

    2014-01-01

    Hundreds of Type 2 quasars have been identified in Sloan Digital Sky Survey (SDSS) data, and there is substantial evidence that they are generally galaxies with highly obscured central engines, in accord with unified models for active galactic nuclei (AGNs). A straightforward expectation of unified models is that highly obscured Type 2 AGNs should show little or no optical variability on timescales of days to years. As a test of this prediction, we have carried out a search for variability in Type 2 quasars in SDSS Stripe 82 using difference-imaging photometry. Starting with the Type 2 AGN catalogs of Zakamska et al. and Reyes et al., we find evidence of significant g-band variability in 17 out of 173 objects for which light curves could be measured from the Stripe 82 data. To determine the nature of this variability, we obtained new Keck spectropolarimetry observations for seven of these variable AGNs. The Keck data show that these objects have low continuum polarizations (p ? 1% in most cases) and all seven have broad H? and/or Mg II emission lines in their total (unpolarized) spectra, indicating that they should actually be classified as Type 1 AGNs. We conclude that the primary reason variability is found in the SDSS-selected Type 2 AGN samples is that these samples contain a small fraction of Type 1 AGNs as contaminants, and it is not necessary to invoke more exotic possible explanations such as a population of 'naked' or unobscured Type 2 quasars. Aside from misclassified Type 1 objects, the Type 2 quasars do not generally show detectable optical variability over the duration of the Stripe 82 survey.

  16. * Systems update

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Systems update * Mendel Move update * Cori update * Edison update * NUG annual meeting * Queues and System Usage * User Survey results * Data movement and networks mini-tutorial * Globus at NERSC * Cori, Edison and all file systems are now in operation at Wang Hall * HPSS remains in Oakland, connected to Wang Hall via a 400 GB/sec network link * A cluster servicing JGI & PDSF is shut down and in process of move from OSF to Wang Hall * No overall Genepool or PDSF downtime due to move 5 - 6 -

  17. Convergence properties of polynomial chaos approximations for L2 random variables.

    SciTech Connect (OSTI)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea (Cornell University, Ithaca, NY)

    2007-03-01

    Polynomial chaos (PC) representations for non-Gaussian random variables are infinite series of Hermite polynomials of standard Gaussian random variables with deterministic coefficients. For calculations, the PC representations are truncated, creating what are herein referred to as PC approximations. We study some convergence properties of PC approximations for L{sub 2} random variables. The well-known property of mean-square convergence is reviewed. Mathematical proof is then provided to show that higher-order moments (i.e., greater than two) of PC approximations may or may not converge as the number of terms retained in the series, denoted by n, grows large. In particular, it is shown that the third absolute moment of the PC approximation for a lognormal random variable does converge, while moments of order four and higher of PC approximations for uniform random variables do not converge. It has been previously demonstrated through numerical study that this lack of convergence in the higher-order moments can have a profound effect on the rate of convergence of the tails of the distribution of the PC approximation. As a result, reliability estimates based on PC approximations can exhibit large errors, even when n is large. The purpose of this report is not to criticize the use of polynomial chaos for probabilistic analysis but, rather, to motivate the need for further study of the efficacy of the method.

  18. Damage measurements on the NWTC direct-drive, variable-speed test bed

    SciTech Connect (OSTI)

    Sutherland, H.J.; Carlin, P.W.

    1998-12-31

    The NWTC (National Wind Technology Center) Variable-Speed Test Bed turbine is a three-bladed, 10-meter, downwind machine that can be run in either fixed-speed or variable-speed mode. In the variable-speed mode, the generator torque is regulated, using a discrete-stepped load bank to maximize the turbine`s power coefficient. At rated power, a second control loop that uses blade pitch to maintain rotor speed essentially as before, i.e., using the load bank to maintain either generator power or (optionally) generator torque. In this paper, the authors will use this turbine to study the effect of variable-speed operation on blade damage. Using time-series data obtained from blade flap and edge strain gauges, the load spectrum for the turbine is developed using rainflow counting techniques. Miner`s rule is then used to determine the damage rates for variable-speed and fixed-speed operation. The results illustrate that the controller algorithm used with this turbine introduces relatively large load cycles into the blade that significantly reduce its service lifetime, while power production is only marginally increased.

  19. Sources of Technical Variability in Quantitative LC-MS Proteomics: Human Brain Tissue Sample Analysis.

    SciTech Connect (OSTI)

    Piehowski, Paul D.; Petyuk, Vladislav A.; Orton, Daniel J.; Xie, Fang; Moore, Ronald J.; Ramirez Restrepo, Manuel; Engel, Anzhelika; Lieberman, Andrew P.; Albin, Roger L.; Camp, David G.; Smith, Richard D.; Myers, Amanda J.

    2013-05-03

    To design a robust quantitative proteomics study, an understanding of both the inherent heterogeneity of the biological samples being studied as well as the technical variability of the proteomics methods and platform is needed. Additionally, accurately identifying the technical steps associated with the largest variability would provide valuable information for the improvement and design of future processing pipelines. We present an experimental strategy that allows for a detailed examination of the variability of the quantitative LC-MS proteomics measurements. By replicating analyses at different stages of processing, various technical components can be estimated and their individual contribution to technical variability can be dissected. This design can be easily adapted to other quantitative proteomics pipelines. Herein, we applied this methodology to our label-free workflow for the processing of human brain tissue. For this application, the pipeline was divided into four critical components: Tissue dissection and homogenization (extraction), protein denaturation followed by trypsin digestion and SPE clean-up (digestion), short-term run-to-run instrumental response fluctuation (instrumental variance), and long-term drift of the quantitative response of the LC-MS/MS platform over the 2 week period of continuous analysis (instrumental stability). From this analysis, we found the following contributions to variability: extraction (72%) >> instrumental variance (16%) > instrumental stability (8.4%) > digestion (3.1%). Furthermore, the stability of the platform and its suitability for discovery proteomics studies is demonstrated.

  20. Wind Levelized Cost of Energy: A Comparison of Technical and Financing Input Variables

    SciTech Connect (OSTI)

    Cory, K.; Schwabe, P.

    2009-10-01

    The expansion of wind power capacity in the United States has increased the demand for project development capital. In response, innovative approaches to financing wind projects have emerged and are proliferating in the U.S. renewable energy marketplace. Wind power developers and financiers have become more efficient and creative in structuring their financial relationships, and often tailor them to different investor types and objectives. As a result, two similar projects may use very different cash flows and financing arrangements, which can significantly vary the economic competitiveness of wind projects. This report assesses the relative impact of numerous financing, technical, and operating variables on the levelized cost of energy (LCOE) associated with a wind project under various financing structures in the U.S. marketplace. Under this analysis, the impacts of several financial and technical variables on the cost of wind electricity generation are first examined individually to better understand the relative importance of each. Then, analysts examine a low-cost and a high-cost financing scenario, where multiple variables are modified simultaneously. Lastly, the analysis also considers the impact of a suite of financial variables versus a suite of technical variables.

  1. Simulating variable source problems via post processing of individual particle tallies

    SciTech Connect (OSTI)

    Bleuel, D.L.; Donahue, R.J.; Ludewigt, B.A.; Vujic, J.

    2000-10-20

    Monte Carlo is an extremely powerful method of simulating complex, three dimensional environments without excessive problem simplification. However, it is often time consuming to simulate models in which the source can be highly varied. Similarly difficult are optimization studies involving sources in which many input parameters are variable, such as particle energy, angle, and spatial distribution. Such studies are often approached using brute force methods or intelligent guesswork. One field in which these problems are often encountered is accelerator-driven Boron Neutron Capture Therapy (BNCT) for the treatment of cancers. Solving the reverse problem of determining the best neutron source for optimal BNCT treatment can be accomplished by separating the time-consuming particle-tracking process of a full Monte Carlo simulation from the calculation of the source weighting factors which is typically performed at the beginning of a Monte Carlo simulation. By post-processing these weighting factors on a recorded file of individual particle tally information, the effect of changing source variables can be realized in a matter of seconds, instead of requiring hours or days for additional complete simulations. By intelligent source biasing, any number of different source distributions can be calculated quickly from a single Monte Carlo simulation. The source description can be treated as variable and the effect of changing multiple interdependent source variables on the problem's solution can be determined. Though the focus of this study is on BNCT applications, this procedure may be applicable to any problem that involves a variable source.

  2. Battery system

    DOE Patents [OSTI]

    Dougherty, Thomas J; Wood, Steven J; Trester, Dale B; Andrew, Michael G

    2013-08-27

    A battery module includes a plurality of battery cells and a system configured for passing a fluid past at least a portion of the plurality of battery cells in a parallel manner.

  3. Flexibility in 21st Century Power Systems (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-10-01

    Flexibility of operation--the ability of a power system to respond to change in demand and supply--is a characteristic of all power systems. Flexibility is especially prized in twenty-first century power systems, with higher levels of grid-connected variable renewable energy (primarily, wind and solar). Sources of flexibility exist--and can be enhanced--across all of the physical and institutional elements of the power system, including system operations and markets, demand side resources and storage; generation; and transmission networks. Accessing flexibility requires significant planning to optimize investments and ensure that both short- and long-time power system requirements are met.

  4. Accelerator Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Accelerator Systems Accelerator Systems MaRIE will provide in-situ dynamic observations of microstructure for transformational materials performance in extremes CONTACT Richard Sheffield (505) 667-1237 Email Revolutionizing Microstructural Physics to Empower Nuclear Energy Realizing MaRIE's full suite of capabilities requires developing and integrating a suite of probes including proton beam radiography, electron radiography and a source of hard, brilliant, and coherent photons. The preferred

  5. Motor System Upgrades Smooth the Way to Savings of $700,000 at...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    PDF icon Motor Systems Upgrades Smooth the Way to Savings of 700,000 at Chevron Refinery (January 1999) More Documents & Publications Variable Speed Pumping: A Guide to Successful ...

  6. Method and system for SCR optimization

    DOE Patents [OSTI]

    Lefebvre, Wesley Curt (Boston, MA); Kohn, Daniel W. (Cambridge, MA)

    2009-03-10

    Methods and systems are provided for controlling SCR performance in a boiler. The boiler includes one or more generally cross sectional areas. Each cross sectional area can be characterized by one or more profiles of one or more conditions affecting SCR performance and be associated with one or more adjustable desired profiles of the one or more conditions during the operation of the boiler. The performance of the boiler can be characterized by boiler performance parameters. A system in accordance with one or more embodiments of the invention can include a controller input for receiving a performance goal for the boiler corresponding to at least one of the boiler performance parameters and for receiving data values corresponding to boiler control variables and to the boiler performance parameters. The boiler control variables include one or more current profiles of the one or more conditions. The system also includes a system model that relates one or more profiles of the one or more conditions in the boiler to the boiler performance parameters. The system also includes an indirect controller that determines one or more desired profiles of the one or more conditions to satisfy the performance goal for the boiler. The indirect controller uses the system model, the received data values and the received performance goal to determine the one or more desired profiles of the one or more conditions. The system model also includes a controller output that outputs the one or more desired profiles of the one or more conditions.

  7. System and method for generating a relationship network

    DOE Patents [OSTI]

    Franks, Kasian (Kensington, CA); Myers, Cornelia A. (St. Louis, MO); Podowski, Raf M. (Pleasant Hill, CA)

    2011-07-26

    A computer-implemented system and process for generating a relationship network is disclosed. The system provides a set of data items to be related and generates variable length data vectors to represent the relationships between the terms within each data item. The system can be used to generate a relationship network for documents, images, or any other type of file. This relationship network can then be queried to discover the relationships between terms within the set of data items.

  8. System and method for generating a relationship network

    DOE Patents [OSTI]

    Franks, Kasian; Myers, Cornelia A; Podowski, Raf M

    2015-05-05

    A computer-implemented system and process for generating a relationship network is disclosed. The system provides a set of data items to be related and generates variable length data vectors to represent the relationships between the terms within each data item. The system can be used to generate a relationship network for documents, images, or any other type of file. This relationship network can then be queried to discover the relationships between terms within the set of data items.

  9. The role of water vapor feedback in unperturbed climate variability and global warming

    SciTech Connect (OSTI)

    Hall, A.; Manabe, Syukuro

    1999-08-01

    To understand the role of water vapor feedback in unperturbed surface temperature variability, a version of the Geophysical Fluid Dynamics Laboratory coupled ocean-atmosphere model is integrated for 1,000 yr in two configurations, one with water vapor feedback and one without. To understand the role of water vapor feedback in global warming, two 500-yr integrations were also performed in which CO{sub 2} was doubled in both model configurations. The final surface global warming in the model with water vapor feedback is 3.38 C, while in the one without it is only 1.05 C. However, the model`s water vapor feedback has a larger impact on surface warming in response to a doubling of CO{sub 2} than it does on internally generated, low-frequency, global-mean surface temperature anomalies. Water vapor feedback`s strength therefore depends on the type of temperature anomaly it affects. Finally, the authors compare the local and global-mean surface temperature time series from both unperturbed variability experiments to the observed record. The experiment without water vapor feedback does not have enough global-scale variability to reproduce the magnitude of the variability in the observed global-mean record, whether or not one removes the warming trend observed over the past century. In contrast, the amount of variability in the experiment with water vapor feedback is comparable to that of the global-mean record, provided the observed warming trend is removed. Thus, the authors are unable to simulate the observed levels of variability without water vapor feedback.

  10. Systems Studies

    SciTech Connect (OSTI)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  11. Quantification of the Variability of Diaphragm Motion and Implications for Treatment Margin Construction

    SciTech Connect (OSTI)

    Rit, Simon; Herk, Marcel van; Zijp, Lambert [Department of Radiation Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Sonke, Jan-Jakob, E-mail: j.sonke@nki.nl [Department of Radiation Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands)

    2012-03-01

    Purpose: To quantify the variability of diaphragm motion during free-breathing radiotherapy of lung patients and its effect on treatment margins to account for geometric uncertainties. Methods and Materials: Thirty-three lung cancer patients were analyzed. Each patient had 5-19 cone-beam scans acquired during different treatment fractions. The craniocaudal position of the diaphragm dome on the same side as the tumor was tracked over 2 min in the projection images, because it is both easily visible and a suitable surrogate to study the variability of the tumor motion and its impact on treatment margins. Intra-acquisition, inter-acquisition, and inter-patient variability of the respiratory cycles were quantified separately, as were the probability density functions (PDFs) of the diaphragm position over each cycle, each acquisition, and each patient. Asymmetric margins were simulated using each patient PDF and compared to symmetric margins computed from a margin recipe. Results: The peak-to-peak amplitude variability (1 SD) was 3.3 mm, 2.4 mm, and 6.1 mm for the intra-acquisition, inter-acquisition, and inter-patient variability, respectively. The average PDF of each cycle was similar to the sin{sup 4} function but the PDF of each acquisition was closer to a skew-normal distribution because of the motion variability. Despite large interfraction baseline variability, the PDF of each patient was generally asymmetric with a longer end-inhale tail because the end-exhale position was more stable than the end-inhale position. The asymmetry of the PDF required asymmetric margins around the time-averaged position to account for the position uncertainty but the average difference was 1.0 mm (range, 0.0-4.4 mm) for a sharp penumbra and an idealized online setup correction protocol. Conclusion: The respiratory motion is more irregular during the fractions than between the fractions. The PDF of the respiratory motion is asymmetrically distributed. Both the intra-acquisition variability and the PDF asymmetry have a limited impact on dose distributions and inferred margins. The use of a margin recipe to account for respiratory motion with an estimate of the average motion amplitude was adequate in almost all patients.

  12. Overview of Variable Renewable Energy Regulatory Issues: A Clean Energy Regulators Initiative Report

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Report NREL/TP-6A20-61350 May 2014 Contract No. DE-AC36-08GO28308 Overview of Variable Renewable Energy Regulatory Issues A CLEAN ENERGY REGULATORS INITIATIVE REPORT Mackay Miller and Sadie Cox National Renewable Energy Laboratory Technical Report NREL/TP-6A20-61350 May 2014 Contract No. DE-AC36-08GO28308 Overview of Variable Renewable Energy Regulatory Issues Mackay Miller and Sadie Cox National Renewable Energy Laboratory Produced under the guidance of the Department of Energy and the Clean

  13. Radiation oncology career decision variables for graduating trainees seeking positions in 2003-2004

    SciTech Connect (OSTI)

    Wilson, Lynn D. . E-mail: lynn.wilson@yale.edu; Flynn, Daniel F.; Haffty, Bruce G.

    2005-06-01

    Purpose: Radiation oncology trainees must consider an array of variables when deciding upon an academic or private practice career path. This prospective evaluation of the 2004 graduating radiation oncology trainees, evaluates such variables and provides additional descriptive data. Methods: A survey that included 15 questions (one subjective, eleven categorical, and 3 continuous variables) was mailed to the 144 graduating radiation oncology trainees in United States programs in January of 2004. Questions were designed to gather information regarding factors that may have influenced career path choices. The responses were anonymous, and no identifying information was sought. Survey data were collated and analyzed for differences in both categorical and continuous variables as they related to choice of academic or private practice career path. Results: Sixty seven (47%) of the surveys were returned. Forty-five percent of respondents indicated pursuit of an academic career. All respondents participated in research during training with 73% participating in research publication authorship. Post graduate year-3 was the median in which career path was chosen, and 20% thought that a fellowship position was 'perhaps' necessary to secure an academic position. Thirty percent of the respondents revealed that the timing of the American Board of Radiology examination influenced their career path decision. Eighteen variables were offered as possibly influencing career path choice within the survey, and the top five identified by those seeking an academic path were: (1) colleagues, (2) clinical research, (3) teaching, (4) geography, (5) and support staff. For those seeking private practice, the top choices were: (1) lifestyle, (2) practice environment, (3) patient care, (4) geography, (5) colleagues. Female gender (p = 0.064), oral meeting presentation (p = 0.053), and international meeting presentation (p 0.066) were the variables most significantly associated with pursuing an academic career path. The following variables were ranked significantly differently in hierarchy (p < 0.05) by those seeking an academic versus private practice path with respect to having influence on the career decision: lifestyle, income, case-mix, autonomy, ability to sub-specialize, basic research, clinical research, teaching, patient care, board structure, practice environment, and mentoring. Conclusion: These data offer descriptive information regarding variables that lead to radiation oncology trainee career path decisions. Such information may be of use in modification of training programs to meet future personnel and programmatic needs within the specialty.

  14. Pacific Decadal Variability and Central Pacific Warming El Nio in a Changing Climate

    SciTech Connect (OSTI)

    Di Lorenzo, Emanuele

    2015-02-27

    This research aimed at understanding the dynamics controlling decadal variability in the Pacific Ocean and its interactions with global-scale climate change. The first goal was to assess how the dynamics and statistics of the El Nio Southern Oscillation and the modes of Pacific decadal variability are represented in global climate models used in the IPCC. The second goal was to quantify how decadal dynamics are projected to change under continued greenhouse forcing, and determine their significance in the context of paleo-proxy reconstruction of long-term climate.

  15. X-ray tests of a two-dimensional stigmatic imaging scheme with variable

    Office of Scientific and Technical Information (OSTI)

    magnifications (Journal Article) | SciTech Connect X-ray tests of a two-dimensional stigmatic imaging scheme with variable magnifications Citation Details In-Document Search Title: X-ray tests of a two-dimensional stigmatic imaging scheme with variable magnifications A two-dimensional stigmatic x-ray imaging scheme, consisting of two spherically bent crystals, one concave and one convex, was recently proposed [M. Bitter et al., Rev. Sci. Instrum. 83, 10E527 (2012)]. The Bragg angles and the

  16. EXPLORING THE VARIABLE SKY WITH LINEAR. III. CLASSIFICATION OF PERIODIC LIGHT CURVES

    SciTech Connect (OSTI)

    Palaversa, Lovro; Eyer, Laurent; Rimoldini, Lorenzo; Ivezi?, eljko; Loebman, Sarah; Hunt-Walker, Nicholas; VanderPlas, Jacob; Westman, David; Becker, Andrew C.; Rudjak, Domagoj; Sudar, Davor; Boi?, Hrvoje; Galin, Mario; Kroflin, Andrea; Mesari?, Martina; Munk, Petra; Vrbanec, Dijana; Sesar, Branimir; Stuart, J. Scott; Srdo?, Gregor; and others

    2013-10-01

    We describe the construction of a highly reliable sample of ?7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg{sup 2} of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter than most other wide-angle surveys; the photometric errors range from ?0.03 mag at r = 15 to ?0.20 mag at r = 18. Light curves include on average 250 data points, collected over about a decade. Using Sloan Digital Sky Survey (SDSS) based photometric recalibration of the LINEAR data for about 25 million objects, we selected ?200,000 most probable candidate variables with r < 17 and visually confirmed and classified ?7000 periodic variables using phased light curves. The reliability and uniformity of visual classification across eight human classifiers was calibrated and tested using a catalog of variable stars from the SDSS Stripe 82 region and verified using an unsupervised machine learning approach. The resulting sample of periodic LINEAR variables is dominated by 3900 RR Lyrae stars and 2700 eclipsing binary stars of all subtypes and includes small fractions of relatively rare populations such as asymptotic giant branch stars and SX Phoenicis stars. We discuss the distribution of these mostly uncataloged variables in various diagrams constructed with optical-to-infrared SDSS, Two Micron All Sky Survey, and Wide-field Infrared Survey Explorer photometry, and with LINEAR light-curve features. We find that the combination of light-curve features and colors enables classification schemes much more powerful than when colors or light curves are each used separately. An interesting side result is a robust and precise quantitative description of a strong correlation between the light-curve period and color/spectral type for close and contact eclipsing binary stars (? Lyrae and W UMa): as the color-based spectral type varies from K4 to F5, the median period increases from 5.9 hr to 8.8 hr. These large samples of robustly classified variable stars will enable detailed statistical studies of the Galactic structure and physics of binary and other stars and we make these samples publicly available.

  17. Systems and methods for modeling and analyzing networks

    DOE Patents [OSTI]

    Hill, Colin C; Church, Bruce W; McDonagh, Paul D; Khalil, Iya G; Neyarapally, Thomas A; Pitluk, Zachary W

    2013-10-29

    The systems and methods described herein utilize a probabilistic modeling framework for reverse engineering an ensemble of causal models, from data and then forward simulating the ensemble of models to analyze and predict the behavior of the network. In certain embodiments, the systems and methods described herein include data-driven techniques for developing causal models for biological networks. Causal network models include computational representations of the causal relationships between independent variables such as a compound of interest and dependent variables such as measured DNA alterations, changes in mRNA, protein, and metabolites to phenotypic readouts of efficacy and toxicity.

  18. Cooling and Heating Season Impacts of Right-Sizing of Fixed- and Variable-Capacity Heat Pumps With Attic and Indoor Ductwork

    SciTech Connect (OSTI)

    Cummings, James; Withers, Charles; Kono, Jamie

    2015-06-24

    A new generation of full variable-capacity air-conditioning (A/C) and heat pump units has come on the market that promises to deliver very high cooling and heating efficiency. The units are controlled differently than standard single-capacity (fixed-capacity) systems. Instead of cycling on at full capacity and cycling off when the thermostat is satisfied, the new units can vary their capacity over a wide range (approximately 40%118% of nominal full capacity) and stay on for 60%100% more hours per day than the fixed-capacity systems depending on load-to-capacity ratios. Two-stage systems were not evaluated in this research effort.

  19. I. The synthesis and characterization of annulated uranocenes. II. The variable temperature /sup 1/H NMR of uranocenes

    SciTech Connect (OSTI)

    Luke, W.D.

    1980-01-01

    A general synthetic route to alkyl annulated cyclooctatetraene dianions and the corresponding annulated uranocenes has been developed. Dideprotonation of bicyclooctatrienes, resulting from reaction of cyclooctatetraene dianion with l,n-dialkylbromides or methanesulfonates, affords alkyl annulated cyclooctatetraene dianions in moderate yields. Dicyclopenteno-, bisdimethylcyclopenteno- and dicyclohexenouranocene were prepared from the corresponding cyclooctatetraene dianions and UCl/sub 4/. The structures of dicyclobuteno- and dicyclopentenouranocene were elucidated by single crystal X-ray diffraction, and the effects of annulation on the uranocene skeleton are discussed. Attempted synthesis of benzocyclooctatetraene and a benzannulated uranocene is reported. The variable temperature /sup 1/H NMR spectrum of uranocene has been reinvestigated from -100 to 100/sup 0/C. The isotropic shift was found to be linear in T/sup -1/ with an extrapolated intercept of 0 at T/sup -1/ = 0. Variable temperature /sup 1/H NMR spectra, from -80 to 70/sup 0/C, of 17 substituted uranocenes are reported. The energy barrier to ring rotation in 1,1', 4,4'-tetra-t-butyl-uranocene was determined to be 8.24 +- 0.5 kcal/mole while the barrier in the corresponding 1,1', 3,3'-tetra-t-butylferrocene was determined to be 13.1 kcal/mole. Alkyl substitution is shown to have little effect on the electronic and magnetic properties of the uranocene skeleton, and thus alkyl substituted uranocenes are treated as having effective axial symmetry in analysis of the observed isotropic shifts. Using diannulated uranocenes as model systems an analysis of the contact and pseudocontact components of the observed isotropic shifts in uranocene and alkyl substituted uranocenes is presented.

  20. Control system for fluid heated steam generator

    DOE Patents [OSTI]

    Boland, James F. (Bonneville County, ID); Koenig, John F. (Idaho Falls, ID)

    1985-01-01

    A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

  1. Foundation of Hydrodynamics of Strongly Interacting Systems

    SciTech Connect (OSTI)

    Wong, Cheuk-Yin

    2014-01-01

    Hydrodynamics and quantum mechanics have many elements in common, as the density field and velocity fields are common variables that can be constructed in both descriptions. Starting with the Schroedinger equation and the Klein-Gordon for a single particle in hydrodynamical form, we examine the basic assumptions under which a quantum system of particles interacting through their mean fields can be described by hydrodynamics.

  2. Control system for fluid heated steam generator

    DOE Patents [OSTI]

    Boland, J.F.; Koenig, J.F.

    1984-05-29

    A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

  3. Luminous and variable stars in M31 and M33. II. Luminous blue variables, candidate LBVs, Fe II emission line stars, and other supergiants

    SciTech Connect (OSTI)

    Humphreys, Roberta M.; Davidson, Kris; Weis, Kerstin; Bomans, D. J.; Burggraf, Birgitta E-mail: kweis@astro.rub.de

    2014-07-20

    An increasing number of non-terminal eruptions are being found in the numerous surveys for optical transients. Very little is known about these giant eruptions, their progenitors and their evolutionary state. A greatly improved census of the likely progenitor class, including the most luminous evolved stars, the luminous blue variables (LBVs), and the warm and cool hypergiants is now needed for a complete picture of the final pre-supernova stages of very massive stars. We have begun a survey of the evolved and unstable luminous star populations in several nearby resolved galaxies. In this second paper on M31 and M33, we review the spectral characteristics, spectral energy distributions, circumstellar ejecta, and evidence for mass loss for 82 luminous and variable stars. We show that many of these stars have warm circumstellar dust including several of the Fe II emission line stars, but conclude that the confirmed LBVs in M31 and M33 do not. The confirmed LBVs have relatively low wind speeds even in their hot, quiescent or visual minimum state compared to the B-type supergiants and Of/WN stars which they spectroscopically resemble. The nature of the Fe II emission line stars and their relation to the LBV state remains uncertain, but some have properties in common with the warm hypergiants and the sgB[e] stars. Several individual stars are discussed in detail. We identify three possible candidate LBVs and three additional post-red supergiant candidates. We suggest that M33-013406.63 (UIT301,B416) is not an LBV/S Dor variable, but is a very luminous late O-type supergiant and one of the most luminous stars or pair of stars in M33.

  4. Commissioning of a Soft X-ray Beamline PF-BL-16A with a Variable-Included-Angle Varied-Line-Spacing Grating Monochromator

    SciTech Connect (OSTI)

    Amemiya, Kenta; Toyoshima, Akio; Kikuchi, Takashi; Kosuge, Takashi; Nigorikawa, Kazuyuki; Sumii, Ryohei; Ito, Kenji

    2010-06-23

    The design and commissioning of a new soft X-ray beamline, BL-16A, at the Photon Factory is presented. The beamline consists of a pre-focusing mirror, an entrance slit, a variable-included-angle varied-line-spacing plane grating monochromator, and a post-focusing system as usual, and provides circularly and linearly polarized soft X rays in the energy range 200-1500 eV with an APPLE-II type undulator. The commissioning procedure for the beamline optics is described in detail, especially the check of the focal position for the zero-th order and diffracted X rays.

  5. Systems Engineering

    Broader source: Energy.gov [DOE]

    Project objectives: to create an interactive, physics based, systems analysis tool for geothermal energy development that will: Identify points of attack to maximize efforts and investment dollars; Identify the parameter space where geothermal energy production is physically and economically viable; Provide a platform for public education and interaction.

  6. Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    SciTech Connect (OSTI)

    Hunt, A.; Easley, S.

    2012-05-01

    The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  7. Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    SciTech Connect (OSTI)

    Hunt, A.; Easley, S.

    2012-05-01

    This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  8. A NEW COSMOLOGICAL DISTANCE MEASURE USING ACTIVE GALACTIC NUCLEUS X-RAY VARIABILITY

    SciTech Connect (OSTI)

    Franca, Fabio La; Bianchi, Stefano; Branchini, Enzo; Matt, Giorgio [Dipartimento di Matematica e Fisica, Universit Roma Tre, Via della Vasca Navale 84, I-00146, Roma (Italy); Ponti, Gabriele, E-mail: lafranca@fis.uniroma3.it [Max-Planck-Institut fr Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei Mnchen (Germany)

    2014-05-20

    We report the discovery of a luminosity distance estimator using active galactic nuclei (AGNs). We combine the correlation between the X-ray variability amplitude and the black hole (BH) mass with the single-epoch spectra BH mass estimates which depend on the AGN luminosity and the line width emitted by the broad-line region. We demonstrate that significant correlations do exist that allow one to predict the AGN (optical or X-ray) luminosity as a function of the AGN X-ray variability and either the H? or the Pa? line widths. In the best case, when the Pa? is used, the relationship has an intrinsic dispersion of ?0.6dex. Although intrinsically more disperse than supernovae Ia, this relation constitutes an alternative distance indicator potentially able to probe, in an independent way, the expansion history of the universe. With respect to this, we show that the new mission concept Athena should be able to measure the X-ray variability of hundreds of AGNs and then constrain the distance modulus with uncertainties of 0.1mag up to z ? 0.6. We also discuss how our estimator has the prospect of becoming a cosmological probe even more sensitive than the current supernovae Ia samples by using a new dedicated wide-field X-ray telescope able to measure the variability of thousands of AGNs.

  9. Assessing the Potential of a Mechanical Continuously Variable Transmission for Wind Turbines

    SciTech Connect (OSTI)

    Cotrell, J.

    2005-08-01

    This paper provides an update to a previous report that summarizes the results of a cooperative research and development agreement (CRADA) between the National Renewable Energy Laboratory (NREL) and Fallbrook Technologies, Inc. (Fallbrook). The purpose of the CRADA is to assess the usefulness of a continuously variable transmission (CVT) for wind turbine applications.

  10. COMPARISON OF KEPLER PHOTOMETRIC VARIABILITY WITH THE SUN ON DIFFERENT TIMESCALES

    SciTech Connect (OSTI)

    Basri, Gibor; Walkowicz, Lucianne M.; Reiners, Ansgar

    2013-05-20

    We utilize Kepler data to study the precision differential photometric variability of solar-type and cooler stars at different timescales, ranging from half an hour to three months. We define a diagnostic that characterizes the median differential intensity change between data bins of a given timescale. We apply the same diagnostics to Solar and Heliospheric Observatory data that has been rendered comparable to Kepler. The Sun exhibits similar photometric variability on all timescales as comparable solar-type stars in the Kepler field. The previously defined photometric ''range'' serves as our activity proxy (driven by starspot coverage). We revisit the fraction of comparable stars in the Kepler field that are more active than the Sun. The exact active fraction depends on what is meant by ''more active than the Sun'' and on the magnitude limit of the sample of stars considered. This active fraction is between a quarter and a third (depending on the timescale). We argue that a reliable result requires timescales of half a day or longer and stars brighter than M{sub Kep} of 14, otherwise non-stellar noise distorts it. We also analyze main sequence stars grouped by temperature from 6500 to 3500 K. As one moves to cooler stars, the active fraction of stars becomes steadily larger (greater than 90% for early M dwarfs). The Sun is a good photometric model at all timescales for those cooler stars that have long-term variability within the span of solar variability.

  11. Invariants and labels for Lie-Poisson Systems

    SciTech Connect (OSTI)

    Thiffeault, J.L.; Morrison, P.J.

    1998-04-01

    Reduction is a process that uses symmetry to lower the order of a Hamiltonian system. The new variables in the reduced picture are often not canonical: there are no clear variables representing positions and momenta, and the Poisson bracket obtained is not of the canonical type. Specifically, we give two examples that give rise to brackets of the noncanonical Lie-Poisson form: the rigid body and the two-dimensional ideal fluid. From these simple cases, we then use the semidirect product extension of algebras to describe more complex physical systems. The Casimir invariants in these systems are examined, and some are shown to be linked to the recovery of information about the configuration of the system. We discuss a case in which the extension is not a semidirect product, namely compressible reduced MHD, and find for this case that the Casimir invariants lend partial information about the configuration of the system.

  12. Fossil fleet transition with fuel changes and large scale variable renewable integration

    SciTech Connect (OSTI)

    James, Revis; Hesler, Stephen; Bistline, John

    2015-03-31

    Variability in demand as seen by grid-connected dispatchable generators can increase due to factors such as greater production from variable generation assets (for example, wind and solar), increased reliance on demand response or customer-driven automation, and aggregation of loads. This variability results a need for these generators to operate in a range of different modes, collectively referred to as “flexible operations.” This study is designed to inform power companies, researchers, and policymakers of the scope and trends in increasing levels of flexible operations as well as reliability challenges and impacts for dispatchable assets. Background Because there is rarely a direct monetization of the value of operational flexibility, the decision to provide such flexibility is typically dependent on unit- and region-specific decisions made by asset owners. It is very likely that much greater and more widespread flexible operations capabilities will be needed due to increased variability in demand seen by grid-connected generators, uncertainty regarding investment in new units to provide adequate operational flexibility, and the retirement of older, uncontrolled sub-critical pulverized coal units. Objective To enhance understanding of the technical challenges and operational impacts associated with dispatchable assets needed to increase operational flexibility and support variable demand. Approach The study approach consists of three elements: a literature review of relevant prior studies, analysis of detailed scenarios for evolution of the future fleet over the next 35 years, and engineering assessment of the degree and scope of technical challenges associated with transformation to the future fleet. The study approach integrated two key elements rarely brought together in a single analysis—1) long-term capacity planning, which enables modeling of unit retirements and new asset investments, and 2) unit commitment analysis, which permits examination of hourly unit dispatch while considering operational limitations relevant to flexible operations capabilities.

  13. Long-term successional forest dynamics: species and community responses to climatic variability

    SciTech Connect (OSTI)

    Kardol, Paul; Todd Jr, Donald E; Hanson, Paul J; Mulholland, Patrick J

    2010-01-01

    Question: Are tree dynamics sensitive to climatic variability, and do tree species differ in their responses to climatic variability? Hence, is vulnerability of forest communities to climatic variability depending on stand composition? Location: Mixed young forest at Walker Branch Watershed near Oak Ridge, East-Tennessee, USA. Methods: Using a long-term data set (1967-2006), we analyzed temporal forest dynamics at the tree and species level, and we analyzed community dynamics for forest stands that different in their initial species composition (i.e., Chestnut Oak, Oak-Hickory, Pine, and Yellow poplar stands). Using summer drought and growing season temperature as defined climate drivers, we evaluated relationships between forest dynamics and climate across levels of organization. Results: Over the 4-decade studied period, forest communities underwent successional change and substantially increased their biomass. Variation in summer drought and growing season temperature contributed to temporal biomass dynamics for some tree species, but not for others. Stand-level responses to climatic variability were shown to be related to responses of specific component species; however, not for Pine stands. Pinus echinata, the dominant species in stands initially identified as Pine stands, decreased over time due to periodical outbreaks of the pine bark beetle (Dendroctonus frontalis). The outbreaks on Walker Branch could not be directly related to climatic conditions. Conclusions: Our results imply that vulnerability of developing forests to predicted climate conditions is stand-type dependent, and hence, is a function of species composition. Autogenic successional processes (or insect outbreaks) were found to prevail over climatic variability in determining long-term forest dynamics for stands dominated by sensitive species, emphasizing the importance of studying interactions between forest succession and climate change.

  14. Burner systems

    DOE Patents [OSTI]

    Doherty, Brian J. (Marblehead, MA)

    1984-07-10

    A burner system particularly useful for downhole deployment includes a tubular combustion chamber unit housed within a tubular coolant jacket assembly. The combustion chamber unit includes a monolithic tube of refractory material whose inner surface defines the combustion zone. A metal reinforcing sleeve surrounds and extends the length of the refractory tube. The inner surface of the coolant jacket assembly and outer surface of the combustion chamber unit are dimensioned so that those surfaces are close to one another in standby condition so that the combustion chamber unit has limited freedom to expand with that expansion being stabilized by the coolant jacket assembly so that compression forces in the refractory tube do not exceed about one-half the safe compressive stress of the material; and the materials of the combustion chamber unit are selected to establish thermal gradient parameters across the combustion chamber unit to maintain the refractory tube in compression during combustion system start up and cool down sequences.

  15. Monitoring Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Systems - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear Energy

  16. Gasification system

    DOE Patents [OSTI]

    Haldipur, Gaurang B. (Hempfield, PA); Anderson, Richard G. (Penn Hills, PA); Cherish, Peter (Bethel Park, PA)

    1985-01-01

    A method and system for injecting coal and process fluids into a fluidized bed gasification reactor. Three concentric tubes extend vertically upward into the fluidized bed. Coal particulates in a transport gas are injected through an inner tube, and an oxygen rich mixture of oxygen and steam are injected through an inner annulus about the inner tube. A gaseous medium relatively lean in oxygen content, such as steam, is injected through an annulus surrounding the inner annulus.

  17. Gasification system

    DOE Patents [OSTI]

    Haldipur, Gaurang B. (Hempfield, PA); Anderson, Richard G. (Penn Hills, PA); Cherish, Peter (Bethel Park, PA)

    1983-01-01

    A method and system for injecting coal and process fluids into a fluidized bed gasification reactor. Three concentric tubes extend vertically upward into the fluidized bed. Coal particulates in a transport gas are injected through an inner tube, and an oxygen rich mixture of oxygen and steam are injected through an inner annulus about the inner tube. A gaseous medium relatively lean in oxygen content, such as steam, is injected through an annulus surrounding the inner annulus.

  18. systems analysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    systems analysis - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear

  19. Computer System,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    System, Cluster, and Networking Summer Institute New Mexico Consortium and Los Alamos National Laboratory HOW TO APPLY Applications will be accepted JANUARY 5 - FEBRUARY 13, 2016 Computing and Information Technology undegraduate students are encouraged to apply. Must be a U.S. citizen. * Submit a current resume; * Offcial University Transcript (with spring courses posted and/or a copy of spring 2016 schedule) 3.0 GPA minimum; * One Letter of Recommendation from a Faculty Member; and * Letter of

  20. Directives System

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1998-01-30

    The Department of Energy (DOE) Directives System is the means by which DOE policies, requirements, and responsibilities are developed and communicated throughout the Department. Directives are used to inform, direct, and guide employees in the performance of their jobs, and to enable employees to work effectively within the Department and with agencies, contractors, and the public. Cancels: DOE O 251.1, DOE M 251.1-1

  1. Braking system

    DOE Patents [OSTI]

    Norgren, D.U.

    1982-09-23

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  2. Grid Impacts of Wind Power Variability: Recent Assessments from a Variety of Utilities in the United States (Presentation)

    SciTech Connect (OSTI)

    Parsons, B.

    2006-03-01

    Presentation for the European Wind Energy Conference held February 27--March 2, 2006, in Athens, Greece, showing grid impacts of wind power variability.

  3. THE GALEX TIME DOMAIN SURVEY. I. SELECTION AND CLASSIFICATION OF OVER A THOUSAND ULTRAVIOLET VARIABLE SOURCES

    SciTech Connect (OSTI)

    Gezari, S.; Martin, D. C.; Forster, K.; Neill, J. D.; Morrissey, P.; Wyder, T. K.; Huber, M.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Magnier, E. A.; Tonry, J. L.; Heckman, T.; Bianchi, L.; Neff, S. G.; Seibert, M.; Schiminovich, D.; Price, P. A.

    2013-03-20

    We present the selection and classification of over a thousand ultraviolet (UV) variable sources discovered in {approx}40 deg{sup 2} of GALEX Time Domain Survey (TDS) NUV images observed with a cadence of 2 days and a baseline of observations of {approx}3 years. The GALEX TDS fields were designed to be in spatial and temporal coordination with the Pan-STARRS1 Medium Deep Survey, which provides deep optical imaging and simultaneous optical transient detections via image differencing. We characterize the GALEX photometric errors empirically as a function of mean magnitude, and select sources that vary at the 5{sigma} level in at least one epoch. We measure the statistical properties of the UV variability, including the structure function on timescales of days and years. We report classifications for the GALEX TDS sample using a combination of optical host colors and morphology, UV light curve characteristics, and matches to archival X-ray, and spectroscopy catalogs. We classify 62% of the sources as active galaxies (358 quasars and 305 active galactic nuclei), and 10% as variable stars (including 37 RR Lyrae, 53 M dwarf flare stars, and 2 cataclysmic variables). We detect a large-amplitude tail in the UV variability distribution for M-dwarf flare stars and RR Lyrae, reaching up to |{Delta}m| = 4.6 mag and 2.9 mag, respectively. The mean amplitude of the structure function for quasars on year timescales is five times larger than observed at optical wavelengths. The remaining unclassified sources include UV-bright extragalactic transients, two of which have been spectroscopically confirmed to be a young core-collapse supernova and a flare from the tidal disruption of a star by dormant supermassive black hole. We calculate a surface density for variable sources in the UV with NUV < 23 mag and |{Delta}m| > 0.2 mag of {approx}8.0, 7.7, and 1.8 deg{sup -2} for quasars, active galactic nuclei, and RR Lyrae stars, respectively. We also calculate a surface density rate in the UV for transient sources, using the effective survey time at the cadence appropriate to each class, of {approx}15 and 52 deg{sup -2} yr{sup -1} for M dwarfs and extragalactic transients, respectively.

  4. Young stellar object variability (YSOVAR): Long timescale variations in the mid-infrared

    SciTech Connect (OSTI)

    Rebull, L. M.; Cody, A. M.; Stauffer, J. R.; Morales-Caldern, M.; Carey, S. J.; Covey, K. R.; Gnther, H. M.; Poppenhaeger, K.; Wolk, S. J.; Hora, J. L.; Hillenbrand, L. A.; Plavchan, P.; Gutermuth, R.; Song, I.; Barrado, D.; Bayo, A.; James, D.; Vrba, F. J.; Alves de Oliveira, C.; Bouvier, J.; and others

    2014-11-01

    The YSOVAR (Young Stellar Object VARiability) Spitzer Space Telescope observing program obtained the first extensive mid-infrared (3.6 and 4.5 ?m) time series photometry of the Orion Nebula Cluster plus smaller footprints in 11 other star-forming cores (AFGL 490, NGC 1333, Mon R2, GGD 12-15, NGC 2264, L1688, Serpens Main, Serpens South, IRAS 20050+2720, IC 1396A, and Ceph C). There are ?29,000 unique objects with light curves in either or both IRAC channels in the YSOVAR data set. We present the data collection and reduction for the Spitzer and ancillary data, and define the 'standard sample' on which we calculate statistics, consisting of fast cadence data, with epochs roughly twice per day for ?40 days. We also define a 'standard sample of members' consisting of all the IR-selected members and X-ray-selected members. We characterize the standard sample in terms of other properties, such as spectral energy distribution shape. We use three mechanisms to identify variables in the fast cadence datathe Stetson index, a ?{sup 2} fit to a flat light curve, and significant periodicity. We also identified variables on the longest timescales possible of six to seven years by comparing measurements taken early in the Spitzer mission with the mean from our YSOVAR campaign. The fraction of members in each cluster that are variable on these longest timescales is a function of the ratio of Class I/total members in each cluster, such that clusters with a higher fraction of Class I objects also have a higher fraction of long-term variables. For objects with a YSOVAR-determined period and a [3.6]-[8] color, we find that a star with a longer period is more likely than those with shorter periods to have an IR excess. We do not find any evidence for variability that causes [3.6]-[4.5] excesses to appear or vanish within our data set; out of members and field objects combined, at most 0.02% may have transient IR excesses.

  5. THE SLUDGE BATCH 7A GLASS VARIABILITY STUDY WITH FRIT 418 AND FRIT 702

    SciTech Connect (OSTI)

    Peeler, D.; Edwards, T.

    2011-03-24

    The Defense Waste Processing Facility (DWPF) is preparing to initiate processing of Sludge Batch 7a (SB7a) in May 2011. To support qualification of SB7a, the Savannah River National Laboratory (SRNL) was requested to execute a variability study (VS) to assess the applicability of the current Product Composition Control System (PCCS) durability models for the Frit 418-SB7a compositional region of interest. The objective of this study was to demonstrate applicability of the current durability models to the SB7a compositional region of interest and acceptability of the SB7a glasses with respect to the Environmental Assessment (EA) glass in terms of durability as defined by the Product Consistency Test (PCT). To support programmatic objectives, twenty-eight SB7a glasses were selected based on the nominal sludge projections used to support the frit recommendation. Twenty-three of the SB7a VS glasses were based on the use of Frit 418, while 5 glasses were based on the use of Frit 702. Frit 702 was also identified as a viable candidate for SB7a, especially if SO{sub 4} concentrations are found to be higher than anticipated. Frit 702 has shown a higher SO{sub 4} retention capability as compared to Frit 418. With respect to acceptability, the PCT results of the SB7a-VS glasses are acceptable relative to the EA glass regardless of thermal history (quenched or canister centerline cooled) or compositional view (target or measured). More specifically, all of the SB7a glasses have normalized boron release values (NL [B]) less than 0.9 g/L as compared to the benchmark NL [B] value for EA of 16.695 g/L. With respect to the applicability of the current durability models to the SB7a VS compositional region of interest, all of the study glasses (based on target compositions) lie within the 95% confidence intervals of the model predictions. When model applicability is based on the measured compositions, all of the SB7a VS glasses are predictable with the exception of SB7aVS-02 and SB7aVS-06. Although the NL [B] values of these two glasses range from 0.66 to 0.73 g/L (considered very acceptable), the PCT responses are not considered predictable by the current durability models. The current durability models are conservative for these glasses since they are more durable than predicted by the models. These two glasses are extreme vertices (EV) based compositions coupled with Frit 418 at 36% WL and target the maximum Na{sub 2}O content (15.01 wt% Na{sub 2}O) of the SB7a VS glasses. Higher alkali glasses for which the model overpredicts the PCT response have been observed previously in the Sludge Batch 3 (SB3) Phase 1 VS and the Sludge Batch 6 (SB6) VS.

  6. Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley

    SciTech Connect (OSTI)

    Jaya Shankar Tumuluru

    2011-08-01

    Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley straw Jaya Shankar Tumuluru*, L. G. Tabil, Y. Song, K. L. Iroba and V. Meda Biomass is a renewable energy source and environmentally friendly substitute for fossil fuels such as coal and petroleum products. Major limitation of biomass for successful energy application is its low bulk density, which makes it very difficult and costly to transport and handle. To overcome this limitation, biomass has to be densified. The commonly used technologies for densification of biomass are pelletization and briquetting. Briquetting offers many advantages at it can densify larger particles sizes of biomass at higher moisture contents. Briquetting is influenced by a number of feedstock and process variables such as moisture content, particle size distribution, and some operating variables such as temperature and densification pressure. In the present study, experiments were designed and conducted based on Box-Behnken design to produce briquettes using barley, wheat, canola and barley straws. A laboratory scale hydraulic briquette press was used for the present study. The experimental process variables and their levels used in the present study were pressure levels (7.5, 10, 12.5 MPa), three levels of temperature (90, 110, 130 C), at three moisture content levels (9, 12, 15% w.b.), and three levels of particle size (19.1, 25.04, 31.75 mm). The quality variables studied includes moisture content, initial density and final briquette density after two weeks of storage, size distribution index and durability. The raw biomass was initially chopped and size reduced using a hammer mill. The ground biomass was conditioned at different moisture contents and was further densified using laboratory hydraulic press. For each treatment combination, ten briquettes were manufactured at a residence time of about 30 s after compression pressure setpoint was achieved. After compression, the initial dimensions and the final dimensions after 2 weeks of storage in controlled environment of all the samples were measured. Durability, dimensional stability, and moisture content tests were conducted after two weeks of storage of the briquettes produced. Initial results indicated that moisture content played a significant role on briquettes durability, stability, and density. Low moisture content of the straws (7-12%) gave more durable briquettes. Briquette density increased with increasing pressure depending on the moisture content value. The axial expansion was more significant than the lateral expansion, which in some cases tended to be nil depending on the material and operating variables. Further data analysis is in progress in order to understand the significance of the process variables based on ANOVA. Regression models were developed to predict the changes in quality of briquettes with respect of the process variables under study. Keywords: Herbaceous biomass, densification, briquettes, density, durability, dimensional stability, ANOVA and regression equations

  7. Employing Twin Crabbing Cavities to Address Variable Transverse Coupling of Beams in the MEIC

    SciTech Connect (OSTI)

    Castilla, Alejandro; Delayen, Jean R.; Morozov, Vasiliy; Satogata, Todd

    2014-07-01

    The design strategy of the Medium Energy Electron-Ion Collider (MEIC) at Jefferson Lab contemplates both matching of the emittance aspect ratios and a 50 mrad crossing angle along with crab crossing scheme for both electron and ion beams over the energy range (?s=20-70 GeV) to achieve high luminosities at the interaction points (IPs). However, the desired locations for placing the crabbing cavities may include regions where the transverse degrees of freedom of the beams are coupled with variable coupling strength that depends on the collider rings magnetic elements (solenoids and skew quadrupoles). In this work we explore the feasibility of employing twin rf dipoles that produce a variable direction crabbing kick to account for a range of transverse coupling of both beams.

  8. Method and apparatus for smart battery charging including a plurality of controllers each monitoring input variables

    DOE Patents [OSTI]

    Hammerstrom, Donald J.

    2013-10-15

    A method for managing the charging and discharging of batteries wherein at least one battery is connected to a battery charger, the battery charger is connected to a power supply. A plurality of controllers in communication with one and another are provided, each of the controllers monitoring a subset of input variables. A set of charging constraints may then generated for each controller as a function of the subset of input variables. A set of objectives for each controller may also be generated. A preferred charge rate for each controller is generated as a function of either the set of objectives, the charging constraints, or both, using an algorithm that accounts for each of the preferred charge rates for each of the controllers and/or that does not violate any of the charging constraints. A current flow between the battery and the battery charger is then provided at the actual charge rate.

  9. Methodology to determine the technical performance and value proposition for grid-scale energy storage systems : a study for the DOE energy storage systems program.

    SciTech Connect (OSTI)

    Byrne, Raymond Harry; Loose, Verne William; Donnelly, Matthew K.; Trudnowski, Daniel J.

    2012-12-01

    As the amount of renewable generation increases, the inherent variability of wind and photovoltaic systems must be addressed in order to ensure the continued safe and reliable operation of the nation's electricity grid. Grid-scale energy storage systems are uniquely suited to address the variability of renewable generation and to provide other valuable grid services. The goal of this report is to quantify the technical performance required to provide di erent grid bene ts and to specify the proper techniques for estimating the value of grid-scale energy storage systems.

  10. Refrigeration system

    SciTech Connect (OSTI)

    Pagani, R.F.; Clarke, K.J.; Avon, E.J.

    1986-11-11

    This patent describes a chamber including an expandable refrigerant system associated therewith. The system comprises reservoir containing an expandable refrigerant coolant and lead piping connecting the reservoir to conduits carrying the coolant therein. The chamber comprises top, bottom and side walls, accordingly defining an interior and an exterior to the chamber, one of the walls comprises a door affording access into the chamber, each of the walls being insulated with insulating material. At least one of the walls comprises a first layer of the insulating material extending thereover adjacent the exterior and a second layer of the insulating material extending thereover adjacent the interior. The reservoir, lead piping and conduits are disposed intermediate the first and second layers of insulating material thereby isolating them from both the interior and exterior. Heat transferring through the at least one wall is substantially absorbed by the coolant and the insulating material cooled by the coolant, before it is able to penetrate through the at least one wall, permitting a product placed in the chamber to effectively maintain or substantially maintain a selected even temperature.

  11. SENSITIVE SEARCH FOR RADIO VARIABLES AND TRANSIENTS IN THE EXTENDED CHANDRA DEEP FIELD SOUTH

    SciTech Connect (OSTI)

    Mooley, K. P.; Kulkarni, S. R.; Horesh, A.; Frail, D. A.; Ofek, E. O.; Miller, N. A.

    2013-05-10

    We report on an analysis of the Extended Chandra Deep Field South (E-CDFS) region using archival data from the Very Large Array, with the goal of studying radio variability and transients at the sub-milliJansky level. The 49 epochs of E-CDFS observations at 1.4 GHz sample timescales from 1 day to 3 months. We find that only a fraction (1%) of unresolved radio sources above 40 {mu}Jy are variable at the 4{sigma} level. There is no evidence that the fractional variability changes along with the known transition of radio-source populations below 1 mJy. Optical identifications of the sources show that the variable radio emission is associated with the central regions of an active galactic nucleus or a star-forming galaxy. After a detailed comparison of the efficacy of various source-finding algorithms, we use the best to carry out a transient search. No transients were found. This implies that the areal density of transients with peak flux density greater than 0.21 mJy is less than 0.37 deg{sup -2} (at a confidence level of 95%). This result is approximately an order of magnitude below the transient rate measured at 5 GHz by Bower et al. but it is consistent with more recent upper limits from Frail et al. Our findings suggest that the radio sky at 1.4 GHz is relatively quiet. For multi-wavelength transient searches, such as the electromagnetic counterparts to gravitational waves, this frequency may be optimal for reducing the high background of false positives.

  12. A New Look into the Treatment of Small-Scale Drop Variability in Radiative Transfer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Look into the Treatment of Small-Scale Drop Variability in Radiative Transfer W. J. Wiscombe and A. Marshak National Aeronautics and Space Administration Goddard Space Flight Center Climate and Radiation Branch Greenbelt, Maryland Y. Knyazikhin Department of Geography Boston University Boston, Massachusetts Introduction Drop size and drop spatial distribution determine photon-cloud interaction. The classical approach assumes that the number of drops of a given radius is proportional to volume

  13. Eddy current nondestructive testing device for measuring variable characteristics of a sample utilizing Walsh functions

    DOE Patents [OSTI]

    Libby, Hugo L. (Richland, WA); Hildebrand, Bernard P. (Richland, WA)

    1978-01-01

    An eddy current testing device for measuring variable characteristics of a sample generates a signal which varies with variations in such characteristics. A signal expander samples at least a portion of this generated signal and expands the sampled signal on a selected basis of square waves or Walsh functions to produce a plurality of signal components representative of the sampled signal. A network combines these components to provide a display of at least one of the characteristics of the sample.

  14. Vertical Variability of Aerosols and Water Vapor Over the Southern Great Plains

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vertical Variability of Aerosols and Water Vapor Over the Southern Great Plains R. A. Ferrare National Aeronautics and Space Administration Langley Research Center Hampton, Virginia D. D. Turner Pacific Northwest National Laboratory Richland, Washington M. Clayton and V. Brackett Science Applications International Corporation National Aeronautics and Space Administration Langley Research Center Hampton, Virginia T. P. Tooman and J. E. M. Goldsmith Sandia National Laboratories Livermore,

  15. Multi-winding Homopolar Electric Machine Offers Variable Voltage at Low

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rotational Speed - Energy Innovation Portal Wind Energy Wind Energy Industrial Technologies Industrial Technologies Find More Like This Return to Search Multi-winding Homopolar Electric Machine Offers Variable Voltage at Low Rotational Speed Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryA nineteenth century invention by Michael Faraday, the Faraday disc machine, has undergone a twenty-first century improvement at ORNL. Now known as a homopolar

  16. Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings A. Hunt and S. Easley Building America Retrofit Alliance (BARA) May 2012 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, subcontractors, or affiliated partners makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy,

  17. Integrating Variable Renewable Energy in Electric Power Markers: Best Practices from International Experience

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience Jaquelin Cochran, Lori Bird, Jenny Heeter, and Douglas J. Arent NREL/TP-6A00-53732 April 2012 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the

  18. Equations Governing Space-Time Variability of Liquid Water Path in Stratus Clouds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Equations Governing Space-Time Variability of Liquid Water Path in Stratus Clouds K. Ivanova Pennsylvania State University University Park, Pennsylvania T. P. Ackerman Pacific Northwest National Laboratory Richland, Washington M. Ausloos University of Liège B-4000 Liège, Belgium Abstract We present a method on how to derive an underlying mathematical (statistical or model free) equation for a liquid water path (LWP) signal directly from empirical data. The evolution of the probability density

  19. Effect of Subgrid Cloud Variability on Parameterization of Indirect Aerosol Effect in Large-Scale Models

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Effect of Subgrid Cloud Variability on Parameterization of Indirect Aerosol Effect in Large-Scale Models M. Ovtchinnikov and S. J. Ghan Pacific Northwest National Laboratory Richland, Washington X. Dong University of Utah Salt Lake City, Utah M. H. Zhang State University of New York Stony Brook, New York Introduction An adequate parameterization of cloud microphysics is essential for estimating the indirect aerosol effect in large-scale models. Such a parameterization must rely on a physically

  20. ACTIVE LEARNING TO OVERCOME SAMPLE SELECTION BIAS: APPLICATION TO PHOTOMETRIC VARIABLE STAR CLASSIFICATION

    SciTech Connect (OSTI)

    Richards, Joseph W.; Starr, Dan L.; Miller, Adam A.; Bloom, Joshua S.; Butler, Nathaniel R.; Berian James, J.; Brink, Henrik; Long, James P.; Rice, John

    2012-01-10

    Despite the great promise of machine-learning algorithms to classify and predict astrophysical parameters for the vast numbers of astrophysical sources and transients observed in large-scale surveys, the peculiarities of the training data often manifest as strongly biased predictions on the data of interest. Typically, training sets are derived from historical surveys of brighter, more nearby objects than those from more extensive, deeper surveys (testing data). This sample selection bias can cause catastrophic errors in predictions on the testing data because (1) standard assumptions for machine-learned model selection procedures break down and (2) dense regions of testing space might be completely devoid of training data. We explore possible remedies to sample selection bias, including importance weighting, co-training, and active learning (AL). We argue that AL-where the data whose inclusion in the training set would most improve predictions on the testing set are queried for manual follow-up-is an effective approach and is appropriate for many astronomical applications. For a variable star classification problem on a well-studied set of stars from Hipparcos and Optical Gravitational Lensing Experiment, AL is the optimal method in terms of error rate on the testing data, beating the off-the-shelf classifier by 3.4% and the other proposed methods by at least 3.0%. To aid with manual labeling of variable stars, we developed a Web interface which allows for easy light curve visualization and querying of external databases. Finally, we apply AL to classify variable stars in the All Sky Automated Survey, finding dramatic improvement in our agreement with the ASAS Catalog of Variable Stars, from 65.5% to 79.5%, and a significant increase in the classifier's average confidence for the testing set, from 14.6% to 42.9%, after a few AL iterations.

  1. Federal Test Procedure Emissions Test Results from Ethanol Variable-Fuel Vehicle Chevrolet Luminas

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Federal Test Procedure Emissions Test Results from Ethanol Variable-Fuel Vehicle Chevrolet Luminas Kenneth J. Kelly, Brent K. Bailey, and Timothy C. Coburn National Renewable Energy Laboratory Wendy Clark Automotive Testing Laboratories, Inc. Peter Lissiuk Environmental Research and Development Corp. Presented at Society for Automotive Engineers International Spring Fuels and Lubricants Meeting Dearborn, MI May 6-8, 1996 The work described here was wholly funded by the U.S. Department of Energy,

  2. Intelligent Transportation Systems Deployment Analysis System...

    Open Energy Info (EERE)

    Transportation Systems Deployment Analysis System AgencyCompany Organization: Cambridge Systematics Sector: Energy Focus Area: Transportation Resource Type: Software...

  3. NREL: Energy Systems Integration Facility - Systems Integration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Systems Integration Systems integration considers the relationships among electricity, thermal, and fuel systems and data and information networks to ensure optimal interoperability across the energy spectrum. The Energy Systems Integration Facility's suite of systems integration laboratories provides advanced capabilities for research, development, and demonstration of key components of future energy systems. Photo of a man and a power quality meter system in a laboratory. The Energy Systems

  4. Influence of variables on the consolidation and unconfined compressive strength of crushed salt: Technical report

    SciTech Connect (OSTI)

    Pfeifle, T.W.; Senseny, P.E.; Mellegard, K.D.

    1987-01-01

    Eight hydrostatic compression creep tests were performed on crushed salt specimens fabricated from Avery Island dome salt. Following the creep test, each specimen was tested in unconfined compression. The experiments were performed to assess the influence of the following four variables on the consolidation and unconfined strength of crushed salt: grain size distribution, temperature, time, and moisture content. The experiment design comprised a half-fraction factorial matrix at two levels. The levels of each variable investigated were grain size distribution, uniform-graded and well-graded (coefficient of uniformity of 1 and 8); temperature 25/sup 0/C and 100/sup 0/C; time, 3.5 x 10/sup 3/s and 950 x 10/sup 3/s (approximately 60 minutes and 11 days, respectively); and moisture content, dry and wet (85% relative humidity for 24 hours). The hydrostatic creep stress was 10 MPa. The unconfined compression tests were performed at an axial strain rate of 1 x 10/sup -5/s/sup -1/. Results show that the variables time and moisture content have the greatest influence on creep consolidation, while grain size distribution and, to a somewhat lesser degree, temperature have the greatest influence on total consolidation. Time and moisture content and the confounded two-factor interactions between either grain size distribution and time or temperature and moisture content have the greatest influence on unconfined strength. 7 refs., 7 figs., 11 tabs.

  5. Understanding cirrus ice crystal number variability for different heterogeneous ice nucleation spectra

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sullivan, S. C.; Morales Betancourt, R.; Barahona, D.; Nenes, A.

    2015-08-11

    Along with minimizing parameter uncertainty, understanding the cause of temporal and spatial variability of nucleated ice crystal number, Ni, is key to improving the representation of cirrus clouds in climate models. To this end, sensitivities of Ni to input variables like aerosol number and diameter provide valuable information about nucleation regime and efficiency for a given model formulation. Here we use the adjoint model of the Barahona and Nenes cirrus formation parameterization to understand Ni variability for various ice-nucleating particle (INP) spectra. Inputs are generated with the Community Atmosphere Model version 5, and simulations are done with a theoretically-derived spectrum,morea lab-based empirical spectrum, and two field-based empirical spectra that differ in the nucleation threshold for black carbon aerosol and in the active site density for dust. The magnitude and sign of Ni sensitivity to insoluble aerosol number can be directly linked to nucleation regime and efficiency of various INP. The lab-based spectrum calculates much higher INP efficiencies than field-based ones, which reveals a disparity in aerosol surface properties. Ni sensitivity to temperature tends to be low, due to the compensating effects of temperature on INP spectrum parameters; this low temperature sensitivity regime has been experimentally reported before but never unraveled as done here.less

  6. THE MICRO-ARCSECOND SCINTILLATION-INDUCED VARIABILITY (MASIV) SURVEY. III. OPTICAL IDENTIFICATIONS AND NEW REDSHIFTS

    SciTech Connect (OSTI)

    Pursimo, Tapio; Ojha, Roopesh; Rickett, Barney J.; Dutka, Michael S.; Koay, Jun Yi; Bignall, Hayley E.; Macquart, Jean-Pierre; Lovell, James E. J.; Kedziora-Chudczer, Lucyna

    2013-04-10

    Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.

  7. Crystal Structure of Neurotropism-Associated Variable Surface Protein 1 (VSP1) of Borrelia Turicatae

    SciTech Connect (OSTI)

    Lawson,C.; Yung, B.; Barbour, A.; Zuckert, W.

    2006-01-01

    Vsp surface lipoproteins are serotype-defining antigens of relapsing fever spirochetes that undergo multiphasic antigenic variation to allow bacterial persistence in spite of an immune response. Two isogenic serotypes of Borrelia turicatae strain Oz1 differ in their Vsp sequences and in disease manifestations in infected mice: Vsp1 is associated with the selection of a neurological niche, while Vsp2 is associated with blood and skin infection. We report here crystal structures of the Vsp1 dimer at 2.7 and 2.2 Angstroms. The structures confirm that relapsing fever Vsp proteins share a common helical fold with OspCs of Lyme disease-causing Borrelia. The fold features an inner stem formed by highly conserved N and C termini and an outer 'dome' formed by the variable central residues. Both Vsp1 and OspC structures possess small water-filled cavities, or pockets, that are lined largely by variable residues and are thus highly variable in shape. These features appear to signify tolerance of the Vsp-OspC fold for imperfect packing of residues at its antigenic surface. Structural comparison of Vsp1 with a homology model for Vsp2 suggests that observed differences in disease manifestation may arise in part from distinct differences in electrostatic surface properties; additional predicted positively charged surface patches on Vsp2 compared to Vsp1 may be sufficient to explain the relative propensity of Vsp2 to bind to acidic glycosaminoglycans.

  8. Genotypic variability in ponderosa pine responses to combined ozone and drought stresses

    SciTech Connect (OSTI)

    Temple, P.J.

    1995-06-01

    Five-year-old ponderosa (Pinus ponderosa Laws.) seedlings from 18 half-sib and one full-sib families obtained from the California Tree Improvement Program were harvested after 1, 2, and 3 growing seasons of exposure to three levels of ozone (O{sub 3}) and two levels of available soil water (ASW) in open-top chambers in the California Sierras. Seedlings were evaluated for O{sub 3} injury symptoms, biomass, and radial growth in response to these stresses. Ozone injury responses were highly variable across families, but family rankings for O{sub 3} injury were consistent across years. Family rankings for O{sub 3} injury were highly correlated with those for reductions in biomass and radial growth for trees in the high ASW treatment, but drought-stressed trees showed no consistent relation between foliar 03 injury and reductions in growth. After three seasons of exposure to 88 ppb O{sub 3}, foliar biomass of the three most susceptible families averaged 60% less than trees in the low-O{sub 3} control, while O{sub 3} had no effect on growth of the three most resistant families. Variability across families of growth responses to drought was significantly less than the variability in seedling responses to O{sub 3}.

  9. Spirometry variability criteria--association with respiratory morbidity and mortality in a cohort of coal miners

    SciTech Connect (OSTI)

    Kellie, S.E.; Attfield, M.D.; Hankinson, J.L.; Castellan, R.M.

    1987-03-01

    To clarify the association between spirometry variability and respiratory morbidity and mortality, the authors analyzed data for miners examined in the first round of the National Coal Study, 1969-1971, and they compared groups of miners who failed with those who met each of two spirometry variability criteria: a 5% criterion recommended by the American Thoracic Society, and a 200 ml criterion used in prior research studies. Compared with miners who met the 5% criterion (the best two forced vital capacities must be within 5% or 100 ml of one another), the group that failed had a lower mean for forced expiratory volume in one second (FEV1), and odds ratios for cough, phlegm, wheeze, shortness of breath, and death of 1.75, 1.67, 1.76, 2.71, and 1.30, respectively. The findings for the 200 ml criterion (the best two FEV1s must be within 200 ml of one another) were somewhat different. The group that failed versus the group that met this criterion had a higher mean for FEV1, and odds ratios for cough, phlegm, wheeze, shortness of breath, and death of 1.13, 1.07, 1.15, 1.43, and 0.94, respectively. Although the findings differ for the two criteria, the findings demonstrate that increased spirometry variability is associated with poorer health.

  10. THE ATTENUATED RADON TRANSFORM: APPLICATION TO SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF A VARIABLE ATTENUATING MEDIUM

    SciTech Connect (OSTI)

    Gullberg, Grant T.

    1980-03-01

    The properties of the attenuated Radon transform and its application to single-photon emission computed tomography (ECT) are analyzed in detail. In nuclear medicine and biological research, the objective of ECT is to describe quantitatively the position and strengths of internal sources of injected radiopharmaceuticals and radionuclides where the attenuation between the sources and detector is unknown. The problem is mathematically and practically quite different from well-known methods in transmission computed tomography (TCT) where only the attenuation is unknown. A mathematical structure using function theory and the theory of linear operators on Hilbert spaces is developed to better understand the spectral properties of the attenuated Radon transform. The continuous attenuated Radon transform is reduced to a matrix operator for discrete angular and lateral sampling, and the reconstruction problem reduces to a system of linear equations. For variable attenuation coefficients frequently found in imaging internal organs, the numerical methods developed in this paper involve iterative techniques of performing the generalized inverse. Its application to nuclear medicine is demonstrated by reconstructions of transverse sections of the brain, heart, and liver.

  11. Analysis and synthesis of the variability of irradiance and PV power time series with the wavelet transform

    SciTech Connect (OSTI)

    Perpinan, O.; Lorenzo, E.

    2011-01-15

    The irradiance fluctuations and the subsequent variability of the power output of a PV system are analysed with some mathematical tools based on the wavelet transform. It can be shown that the irradiance and power time series are nonstationary process whose behaviour resembles that of a long memory process. Besides, the long memory spectral exponent {alpha} is a useful indicator of the fluctuation level of a irradiance time series. On the other side, a time series of global irradiance on the horizontal plane can be simulated by means of the wavestrapping technique on the clearness index and the fluctuation behaviour of this simulated time series correctly resembles the original series. Moreover, a time series of global irradiance on the inclined plane can be simulated with the wavestrapping procedure applied over a signal previously detrended by a partial reconstruction with a wavelet multiresolution analysis, and, once again, the fluctuation behaviour of this simulated time series is correct. This procedure is a suitable tool for the simulation of irradiance incident over a group of distant PV plants. Finally, a wavelet variance analysis and the long memory spectral exponent show that a PV plant behaves as a low-pass filter. (author)

  12. Development of the Variable Atmosphere Testing Facility for Blow-Down Analysis of the Mars Hopper Prototype

    SciTech Connect (OSTI)

    Nathan D. Jerred; Robert C. O'Brien; Steven D. Howe; James E. O'Brien

    2013-02-01

    Recent developments at the Center for Space Nuclear Research (CSNR) on a Martian exploration probe have lead to the assembly of a multi-functional variable atmosphere testing facility (VATF). The VATF has been assembled to perform transient blow-down analysis of a radioisotope thermal rocket (RTR) concept that has been proposed for the Mars Hopper; a long-lived, long-ranged mobile platform for the Martian surface. This study discusses the current state of the VATF as well as recent blow-down testing performed on a laboratory-scale prototype of the Mars Hopper. The VATF allows for the simulation of Mars ambient conditions within the pressure vessel as well as to safely perform blow-down tests through the prototype using CO2 gas; the proposed propellant for the Mars Hopper. Empirical data gathered will lead to a better understanding of CO2 behavior and will provide validation of simulation models. Additionally, the potential of the VATF to test varying propulsion system designs has been recognized. In addition to being able to simulate varying atmospheres and blow-down gases for the RTR, it can be fitted to perform high temperature hydrogen testing of fuel elements for nuclear thermal propulsion.

  13. A NEW SUB-PERIOD-MINIMUM CATACLYSMIC VARIABLE WITH PARTIAL HYDROGEN DEPLETION AND EVIDENCE OF SPIRAL DISK STRUCTURE

    SciTech Connect (OSTI)

    Littlefield, C.; Garnavich, P.; Magno, K.; Applegate, A.; Pogge, R.; Irwin, J.; Marion, G. H.; Kirshner, R.; Vinko, J.

    2013-06-15

    We present time-resolved spectroscopy and photometry of CSS 120422:111127+571239 (=SBS 1108+574), a recently discovered SU UMa-type dwarf nova whose 55 minute orbital period is well below the cataclysmic variable (CV) period minimum of {approx}78 minutes. In contrast with most other known CVs, its spectrum features He I emission of comparable strength to the Balmer lines, implying a hydrogen abundance less than 0.1 of long-period CVs-but still at least 10 times higher than that in AM CVn stars. Together, the short orbital period and remarkable helium-to-hydrogen ratio suggest that mass transfer in CSS 120422 began near the end of the donor star's main-sequence lifetime, meaning that this CV is a strong candidate progenitor of an AM CVn system as described by Podsiadlowski et al. Moreover, a Doppler tomogram of the H{alpha} line reveals two distinct regions of enhanced emission. While one is the result of the stream-disk impact, the other is probably attributable to spiral disk structure generated when material in the outer disk achieves a 2:1 orbital resonance with respect to the donor.

  14. Power applications of high-temperature superconductivity: Variable speed motors, current switches, and energy storage for end use

    SciTech Connect (OSTI)

    Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Banerjee, B.B.; Grant, P.M. [Electric Power Research Inst., Palo Alto, CA (United States)

    1996-08-01

    The objective of this project is to conduct joint research and development activities related to certain electric power applications of high-temperature superconductivity (HTS). The new superconductors may allow development of an energy-efficient switch to control current to variable speed motors, superconducting magnetic energy storage (SMES) systems, and other power conversion equipment. Motor types that were considered include induction, permanent magnet, and superconducting ac motors. Because it is impractical to experimentally alter certain key design elements in radial-gap motors, experiments were conducted on an axial field superconducting motor prototype using 4 NbTi magnets. Superconducting magnetic energy storage technology with 0.25--5 kWh stored energy was studied as a viable solution to short duration voltage sag problems on the customer side of the electric meter. The technical performance characteristics of the device wee assembled, along with competing technologies such as active power line conditioners with storage, battery-based uninterruptible power supplies, and supercapacitors, and the market potential for SMES was defined. Four reports were prepared summarizing the results of the project.

  15. Power Systems Engineering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    systems; steam, water, fuel, and environmental monitoring systems; alternative energy systems; reliability, availability, and maintainability assessments; and associated...

  16. Transfer system

    DOE Patents [OSTI]

    Kurosawa, Kanji; Koga, Bunichiro; Ito, Hideki; Kiriyama, Shigeru; Higuchi, Shizuo

    2003-05-20

    A transport system includes a traveling rail (1) which constitutes a transport route and a transport body (3) which is capable of traveling on the traveling rail in the longitudinal direction of the traveling rail. Flexible drive tubes (5) are arranged on the traveling rail in the longitudinal direction of the traveling rail. The transport body includes a traveling wheel (4) which is capable of rolling on the traveling rail and drive wheels (2) which are capable of rolling on the drive tubes upon receiving the rotational drive power generated by pressure of a pressure medium supplied to the drive tubes while depressing the drive tubes. The traveling rail includes a plurality of transport sections and the transport body is capable of receiving a rotational drive force from the drive tubes at every transport sections. If necessary, a transport route changeover switch which changes over the transport route can be provided between the transport sections.

  17. Boosting Small Engines to High Performance - Boosting Systems and

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion Development Methodology | Department of Energy Boosting Small Engines to High Performance - Boosting Systems and Combustion Development Methodology Boosting Small Engines to High Performance - Boosting Systems and Combustion Development Methodology Overview on combustion approaches and challenges for smaller boosted engines to improve vehicle fuel economy, particularly downsizing gasoline engines PDF icon deer12_kleeberg.pdf More Documents & Publications Two-Stage Variable

  18. System and method for anomaly detection

    DOE Patents [OSTI]

    Scherrer, Chad

    2010-06-15

    A system and method for detecting one or more anomalies in a plurality of observations is provided. In one illustrative embodiment, the observations are real-time network observations collected from a stream of network traffic. The method includes performing a discrete decomposition of the observations, and introducing derived variables to increase storage and query efficiencies. A mathematical model, such as a conditional independence model, is then generated from the formatted data. The formatted data is also used to construct frequency tables which maintain an accurate count of specific variable occurrence as indicated by the model generation process. The formatted data is then applied to the mathematical model to generate scored data. The scored data is then analyzed to detect anomalies.

  19. Reduce air, reduce compliance cost new patented spray booth technology

    SciTech Connect (OSTI)

    McGinnis, F.

    1997-12-31

    A New Paint Spray Booth System that dramatically reduces air volumes normally required for capturing and controlling paint overspray that contains either Volatile Organic Compounds (VOC) or Hazardous Air Pollutants (HAP), or both. In turn, a substantial reduction in capital equipment expenditures for air abatement systems and air make-up heaters as well as related annual operating expenses is realized.

  20. Advanced Strategy Guideline. Air Distribution Basics and Duct Design

    SciTech Connect (OSTI)

    Burdick, Arlan

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings.

  1. Analysis of the Effects of a Flexible Ramping Ancillary Service Product on Power System Operations: Preprint

    SciTech Connect (OSTI)

    Krad, Ibrahim; Ibanez, Eduardo; Ela, Erik

    2015-10-19

    The recent increased interest in utilizing variable generation (VG) resources such as wind and solar in power systems has motivated investigations into new operating procedures. Although these resources provide desirable value to a system (e.g., no fuel costs or emissions), interconnecting them provides unique challenges. Their variable, non-controllable nature in particular requires significant attention, because it directly results in increased power system variability and uncertainty. One way to handle this is via new operating reserve schemes. Operating reserves provide upward and downward generation and ramping capacity to counteract uncertainty and variability prior to their realization. For instance, uncertainty and variability in real-time dispatch can be accounted for in the hour-ahead unit commitment. New operating reserve methodologies that specifically account for the increased variability and uncertainty caused by VG are currently being investigated and developed by academia and industry. This paper examines one method inspired by the new operating reserve product being proposed by the California Independent System Operator. The method is based on examining the potential ramping requirements at any given time and enforcing those requirements via a reserve demand curve in the market-clearing optimization as an additional ancillary service product.

  2. Models Used to Assess the Performance of Photovoltaic Systems

    Broader source: Energy.gov [DOE]

    This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization.

  3. Heat recovery and the economizer for HVAC systems

    SciTech Connect (OSTI)

    Anantapantula, V.S. . Alco Controls Div.); Sauer, H.J. Jr. )

    1994-11-01

    This articles examines why a combined heat reclaim/economizer system with priority to heat reclaim operation is most likely to result in the least annual total HVAC energy. PC-based, hour-by-hour simulation programs evaluate annual HVAC energy requirements when using combined operation of heat reclaim and economizer cycle, while giving priority to operation of either one. These simulation programs also enable the design engineer to select the most viable heat reclaim and/or economizer system for any given type of HVAC system serving the building internal load level, building geographical location and other building/system variables.

  4. PMU Placement for Dynamic State Tracking of Power Systems

    SciTech Connect (OSTI)

    Sun, Yannan; Du, Pengwei; Huang, Zhenyu; Kalsi, Karanjit; Diao, Ruisheng; Anderson, Kevin K.; Li, Yulan; Lee, Barry

    2011-08-04

    Accurately tracking the state variables (rotor angle and speed) is a necessity for monitoring system stability conditions and assessing the risks of large-scale system collapse. This paper explores how the number and locations of PMUs installed in the system are determined to ensure satisfactory state tracking performance. A search algorithm is presented for determining PMU placement (location and quantity). The algorithm determines a placement that gives small tracking error in polynomial time. A modified, scalable algorithm is also presented. Observability in the presence of faults is considered. Simulation results for a 16-machine and a 50-machine system are provided.

  5. Stressor Interactions in Ecological Systems

    SciTech Connect (OSTI)

    Clements, Will; Luoma, Samuel N.; Gerritsen, Jeroen; Hatch, Audrey; Jepson, Paul; Reynoldson, Trefor; Thom, Ronald M.

    2001-12-03

    Here we ask what types of field studies can best detect interactions among stressors and allow us to separate and rank the relative importance of individual stressors in systems receiving multiple disturbances (natural and/or anthropogenic). If multiple stressor responses are common in nature, then single variable tests, such as analysis of a biomarker in isolation or along a surmised gradient, or studies that exclude variables other than pollutants, could be insensitive to all but the most extreme influences of contamination. Preponderance of evidence approaches will be similarly insensitive if designs are too simplistic. A combination of persistent and intensive study of exposure and response in the field, study of critical ecosystem-specific and organism-specific processes, as well as iteration with experimental studies, are useful (and perhaps necessary) strategies to discern interactions among stressors. As our understanding of the mechanisms responsible for changes at lower levels of organization improves, responses to complex stressors become more predictable. This improved mechanistic understanding could lead to a similar degree of understanding for responses at higher levels of biological organization. Below we discuss three examples where researchers have attempted to identify and quantify the relative importance of individual stressors in systems receiving complex stressors. The first example demonstrates how intensive field studies identified multiple stressors and how a management plan resulted in mitigation of these stressors. The second example describes a series of field experiments designed to identify the relative importance of water quality and substrate quality on benthic macroinvertebrates in a metal-polluted stream. The final example illustrates the difficulty of sorting out the direct and indirect influences of global climate change on populations.

  6. Compressed Air Systems

    Broader source: Energy.gov [DOE]

    There are incentives for variable frequency drive screw compressors (10-40 HP), air receivers/tanks for load/no-load compressors, cycling refrigerated dryers (up to 200 CFM capacity), no-loss...

  7. NREL: Energy Systems Integration - Systems Integration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Systems Integration Systems Integration considers the relationships among electricity, thermal, and fuel systems and data and information networks to ensure optimal integration and interoperability across the entire energy system spectrum. Advanced R&D in systems integration ranges from technology innovation to electric, fuel, thermal, and water infrastructure deployment. System integration research areas include: Prototype testing through hardware-in-the-loop Energy system integration

  8. Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate

    SciTech Connect (OSTI)

    Deng, Yi

    2014-11-24

    DOE-GTRC-05596 11/24/2104 Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate PI: Dr. Yi Deng (PI) School of Earth and Atmospheric Sciences Georgia Institute of Technology 404-385-1821, yi.deng@eas.gatech.edu El Niño-Southern Oscillation (ENSO) and Annular Modes (AMs) represent respectively the most important modes of low frequency variability in the tropical and extratropical circulations. The projection of future changes in the ENSO and AM variability, however, remains highly uncertain with the state-of-the-science climate models. This project conducted a process-resolving, quantitative evaluations of the ENSO and AM variability in the modern reanalysis observations and in climate model simulations. The goal is to identify and understand the sources of uncertainty and biases in models’ representation of ENSO and AM variability. Using a feedback analysis method originally formulated by one of the collaborative PIs, we partitioned the 3D atmospheric temperature anomalies and surface temperature anomalies associated with ENSO and AM variability into components linked to 1) radiation-related thermodynamic processes such as cloud and water vapor feedbacks, 2) local dynamical processes including convection and turbulent/diffusive energy transfer and 3) non-local dynamical processes such as the horizontal energy transport in the oceans and atmosphere. In the past 4 years, the research conducted at Georgia Tech under the support of this project has led to 15 peer-reviewed publications and 9 conference/workshop presentations. Two graduate students and one postdoctoral fellow also received research training through participating the project activities. This final technical report summarizes key scientific discoveries we made and provides also a list of all publications and conference presentations resulted from research activities at Georgia Tech. The main findings include: 1) the distinctly different roles played by atmospheric dynamical processes in establishing surface temperature response to ENSO at tropics and extratropics (i.e., atmospheric dynamics disperses energy out of tropics during ENSO warm events and modulate surface temperature at mid-, high-latitudes through controlling downward longwave radiation); 2) the representations of ENSO-related temperature response in climate models fail to converge at the process-level particularly over extratropics (i.e., models produce the right temperature responses to ENSO but with wrong reasons); 3) water vapor feedback contributes substantially to the temperature anomalies found over U.S. during different phases of the Northern Annular Mode (NAM), which adds new insight to the traditional picture that cold/warm advective processes are the main drivers of local temperature responses to the NAM; 4) the overall land surface temperature biases in the latest NCAR model (CESM1) are caused by biases in surface albedo while the surface temperature biases over ocean are related to multiple factors including biases in model albedo, cloud and oceanic dynamics, and the temperature biases over different ocean basins are also induced by different process biases. These results provide a detailed guidance for process-level model turning and improvement, and thus contribute directly to the overall goal of reducing model uncertainty in projecting future changes in the Earth’s climate system, especially in the ENSO and AM variability.

  9. Separation system

    DOE Patents [OSTI]

    Rubin, Leslie S. (Newton, MA)

    1986-01-01

    A separation system for dewatering radioactive waste materials includes a disposal container, drive structure for receiving the container, and means for releasably attaching the container to the drive structure. Separation structure disposed in the container adjacent the inner surface of the side wall structure retains solids while allowing passage of liquids. Inlet port structure in the container top wall is normally closed by first valve structure that is centrifugally actuated to open the inlet port and discharge port structure at the container periphery receives liquid that passes through the separation structure and is normally closed by second valve structure that is centrifugally actuated to open the discharge ports. The container also includes coupling structure for releasable engagement with the centrifugal drive structure. Centrifugal force produced when the container is driven in rotation by the drive structure opens the valve structures, and radioactive waste material introduced into the container through the open inlet port is dewatered, and the waste is compacted. The ports are automatically closed by the valves when the container drum is not subjected to centrifugal force such that containment effectiveness is enhanced and exposure of personnel to radioactive materials is minimized.

  10. Measurements of reactive trace gases and variable O3 formation rates in some South Carolina biomass burning plumes

    SciTech Connect (OSTI)

    Akagi, Sheryl; Yokelson, Robert J.; Burling, Ian R.; Meinardi, S.; Simpson, I.; Blake, D. R.; McMeeking, Gavin; Sullivan, Amy; Lee, Taehyoung; Kredenweis, Sonia; Urbanski, Shawn; Reardon, James; Griffith, David WT; Johnson, Timothy J.; Weise, David

    2013-02-01

    In October-November 2011 we measured the trace gas emission factors from 7 prescribed fires in South Carolina, U.S. using two Fourier transform infrared spectrometer (FTIR) systems and whole air sampling (WAS) into canisters followed by gas-chromatographic analyses. The fires were intended to emulate high-intensity burns as they were lit during the dry season and in most cases represented stands that had not been treated with prescribed burns in 10+ years, if at all. A total of 97 trace gas species are reported here from both airborne and ground-based platforms making this one of the most detailed field studies of fire emissions to date. The measurements included the first data for a suite of monoterpene compounds emitted via distillation of plant tissues during real fires. The known chemistry of the monoterpenes and their measured abundance of ~0.40% of CO (molar basis), ~3.9% of NMOC (molar basis), and ~21% of organic aerosol (mass basis), suggests that they impacted post-emission formation of ozone, aerosol, and small organic trace gases such as methanol and formaldehyde in the sampled plumes. The variability in the terpene emissions in South Carolina (SC) fire plumes was high and, in general, the speciation of the emitted gas-phase non-methane organic compounds was surprisingly different from that observed in a similar study in nominally similar pine forests in North Carolina ~20 months earlier. It is likely that the slightly different ecosystems, time of year and the precursor variability all contributed to the variability in plume chemistry observed in this study and in the literature. The ?HCN/?CO emission ratio, however, is fairly consistent at 0.9 0.06 % for airborne fire measurements in coniferous-dominated ecosystems further confirming the value of HCN as a good biomass burning indicator/tracer. The SC results also support an earlier finding that C3-C4 alkynes may be of use as biomass burning indicators on the time-scale of hours to a day. It was possible to measure the chemical evolution of the plume on four of the fires and significant ozone (O3) formation (?O3/?CO from 10-90%) occurred in all of these plumes. Slower O3 production was observed on a cloudy day with low co-emissions of NOx and the fastest O3 production was observed on a sunny day when the plume almost certainly incorporated significant additional NOx by passing over the Columbia, SC metropolitian area. Due to rapid plume dilution, it was only possible to acquire high quality downwind data for two other species (formaldehyde and methanol) on two of the fires. In all four cases significant increases were observed. This is likely the first direct observation of post-emission methanol production in biomass burning plumes and the precursors likely included terpenes.

  11. Changes in the Economic Value of Variable Generation at High Penetration Levels: A Pilot Case Study of California

    SciTech Connect (OSTI)

    Mills, Andrew; Wiser, Ryan

    2012-05-18

    We estimate the long-run economic value of variable renewable generation with increasing penetration using a unique investment and dispatch model that captures long-run investment decisions while also incorporating detailed operational constraints and hourly time resolution over a full year. High time resolution and the incorporation of operational constraints are important for estimating the economic value of variable generation, as is the use of a modeling framework that accommodates new investment decisions. The model is herein applied with a case study that is loosely based on California in 2030. Increasing amounts of wind, photovoltaics (PV), and concentrating solar power (CSP) with and without thermal energy storage (TES) are added one at a time. The marginal economic value of these renewable energy sources is estimated and then decomposed into capacity value, energy value, day-ahead forecast error cost, and ancillary services. The marginal economic value, as defined here, is primarily based on the combination of avoided capital investment cost and avoided variable fuel and operations and maintenance costs from other power plants in the power system. Though the model only captures a subset of the benefits and costs of renewable energy, it nonetheless provides unique insights into how the value of that subset changes with technology and penetration level. Specifically, in this case study implementation of the model, the marginal economic value of all three solar options is found to exceed the value of a flat-block of power (as well as wind energy) by \\$20--30/MWh at low penetration levels, largely due to the high capacity value of solar at low penetration. Because the value of CSP per unit of energy is found to be high with or without thermal energy storage at low penetration, we find little apparent incremental value to thermal storage at low solar penetration in the present case study analysis. The marginal economic value of PV and CSP without thermal storage is found to drop considerably (by more than \\$70/MWh) as the penetration of solar increases toward 30\\percent on an energy basis. This is due primarily to a steep drop in capacity value followed by a decrease in energy value. In contrast, the value of CSP with thermal storage drops much less dramatically as penetration increases. As a result, at solar penetration levels above 10\\percent, CSP with thermal storage is found to be considerably more valuable relative to PV and CSP without thermal storage. The marginal economic value of wind is found to be largely driven by energy value, and is lower than solar at low penetration. The marginal economic value of wind drops at a relatively slower rate with penetration, however. As a result, at high penetration, the value of wind can exceed the value of PV and CSP without thermal storage. Though some of these findings may be somewhat unique to the specific case study presented here, the results: (1) highlight the importance of an analysis framework that addresses long-term investment decisions as well as short-term dispatch and operational constraints, (2) can help inform long-term decisions about renewable energy procurement and supporting infrastructure, and (3) point to areas where further research is warranted.

  12. Forecasting Wind and Solar Generation: Improving System Operations, Greening the Grid

    SciTech Connect (OSTI)

    2016-01-01

    This document discusses improving system operations with forecasting and solar generation. By integrating variable renewable energy (VRE) forecasts into system operations, power system operators can anticipate up- and down-ramps in VRE generation in order to cost-effectively balance load and generation in intra-day and day-ahead scheduling. This leads to reduced fuel costs, improved system reliability, and maximum use of renewable resources.

  13. Pump Life Cycle Costs: A Guide to LCC Analysis for Pumping Systems -

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Executive Summary | Department of Energy Life Cycle Costs: A Guide to LCC Analysis for Pumping Systems - Executive Summary Pump Life Cycle Costs: A Guide to LCC Analysis for Pumping Systems - Executive Summary This brochure is a management tool that can help companies minimize waste and maximize energy efficiency for pumping systems. PDF icon Pump Life Cycle Costs: A Guide to LCC Analysis for Pumping Systems - Executive Summary (January 2001) More Documents & Publications Variable Speed

  14. Advanced Manufacturing Office: Case Study - The Challenge: Improving Ventilation System Energy Efficiency in a Textile Plant

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cotton Fabric Process: Facility Ventilation System: Ventilation Fans Technology: Variable Frequency Drives (VFDs) Project Profile U.S. Department of Energy - Energy Efficiency and Renewable Energy Advanced Manufacturing Office Case Study - The Challenge: Improving Ventilation System Energy Efficiency in a Textile Plant Summary Company Background Project Overview Project Team The Systems Approach Project Implementation Results Lessons Learned Summary In an effort to improve ventilation system

  15. Investigating Broadband Variability of the TeV Blazar 1ES 1959+650

    SciTech Connect (OSTI)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; Buckley, J. H.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Cui, W.; Dumm, J.; Eisch, J. D.; Falcone, A.; Federici, S.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Hanna, D.; Holder, J.; Hughes, G.; Hughes, Z.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kar, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Madhavan, A. S.; Majumdar, P.; McArthur, S.; McCann, A.; Meagher, K.; Millis, J.; Moriarty, P.; Mukherjee, R.; Nelson, T.; Nieto, D.; O'Faolain de Bhroithe, A.; Ong, R. A.; Otte, A. N.; Park, N.; Perkins, J. S.; Pohl, M.; Popkow, A.; Prokoph, H.; Quinn, J.; Ragan, K.; Rajotte, J.; Reyes, L. C.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Sadun, A.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Sheidaei, F.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Theiling, M.; Tyler, J.; Varlotta, A.; Vassiliev, V. V.; Vincent, S.; Wakeley, S. P.; Weekes, T. C.; Weinstein, A.; Welsing, R.; Wilhelm, A.; Williams, D. A.; Zitzer, B.; Boettcher, M.; Fumagalli, M.

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift Ultraviolet and Optical Telescope, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters required to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.

  16. Investigating broadband variability of the TeV blazar 1ES 1959+650

    SciTech Connect (OSTI)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; Buckley, J. H.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Cui, W.; Dumm, J.; Eisch, J. D.; Falcone, A.; Federici, S.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Fortin, P.; Fortson, L.; Furniss, A.; Galante, N.; Gillanders, G. H.; Griffin, S.; Griffiths, S. T.; Grube, J.; Gyuk, G.; Håkansson, N.; Hanna, D.; Holder, J.; Hughes, G.; Hughes, Z.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kar, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Madhavan, A. S.; Majumdar, P.; McArthur, S.; McCann, A.; Meagher, K.; Millis, J.; Moriarty, P.; Mukherjee, R.; Nelson, T.; Nieto, D.; de Bhróithe, A. O'Faoláin; Ong, R. A.; Otte, A. N.; Park, N.; Perkins, J. S.; Pohl, M.; Popkow, A.; Prokoph, H.; Quinn, J.; Ragan, K.; Rajotte, J.; Reyes, L. C.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Sadun, A.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Sheidaei, F.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Theiling, M.; Tyler, J.; Varlotta, A.; Vassiliev, V. V.; Vincent, S.; Wakely, S. P.; Weekes, T. C.; Weinstein, A.; Welsing, R.; Wilhelm, A.; Williams, D. A.; Zitzer, and B.; Böttcher, M.; Fumagalli, M.

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift UVOT, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters required to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.

  17. MEASURING X-RAY VARIABILITY IN FAINT/SPARSELY SAMPLED ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Allevato, V.; Paolillo, M.; Papadakis, I.; Pinto, C.

    2013-07-01

    We study the statistical properties of the normalized excess variance of variability process characterized by a ''red-noise'' power spectral density (PSD), as in the case of active galactic nuclei (AGNs). We perform Monte Carlo simulations of light curves, assuming both a continuous and a sparse sampling pattern and various signal-to-noise ratios (S/Ns). We show that the normalized excess variance is a biased estimate of the variance even in the case of continuously sampled light curves. The bias depends on the PSD slope and on the sampling pattern, but not on the S/N. We provide a simple formula to account for the bias, which yields unbiased estimates with an accuracy better than 15%. We show that the normalized excess variance estimates based on single light curves (especially for sparse sampling and S/N < 3) are highly uncertain (even if corrected for bias) and we propose instead the use of an ''ensemble estimate'', based on multiple light curves of the same object, or on the use of light curves of many objects. These estimates have symmetric distributions, known errors, and can also be corrected for biases. We use our results to estimate the ability to measure the intrinsic source variability in current data, and show that they could also be useful in the planning of the observing strategy of future surveys such as those provided by X-ray missions studying distant and/or faint AGN populations and, more in general, in the estimation of the variability amplitude of sources that will result from future surveys such as Pan-STARRS and LSST.

  18. Investigating broadband variability of the TeV blazar 1ES 1959+650

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; et al

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift UVOT, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters requiredmore » to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.« less

  19. Examining the infrared variable star population discovered in the Small Magellanic Cloud using the SAGE-SMC survey

    SciTech Connect (OSTI)

    Polsdofer, Elizabeth; Marengo, M.; Seale, J.; Sewi?o, M.; Vijh, U. P.; Terrazas, M.; Meixner, M.

    2015-02-01

    We present our study on the infrared variability of point sources in the Small Magellanic Cloud (SMC). We use the data from the Spitzer Space Telescope Legacy Program Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity Small Magellanic Cloud (SAGE-SMC) and the Spitzer Survey of the Small Magellanic Cloud (S{sup 3}MC) survey, over three different epochs, separated by several months to 3 years. Variability in the thermal infrared is identified using a combination of Spitzers InfraRed Array Camera 3.6, 4.5, 5.8, and 8.0 ?m bands, and the Multiband Imaging Photometer for Spitzer 24 ?m band. An error-weighted flux difference between each pair of three epochs (variability index) is used to assess the variability of each source. A visual source inspection is used to validate the photometry and image quality. Out of ?2 million sources in the SAGE-SMC catalog, 814 meet our variability criteria. We matched the list of variable star candidates to the catalogs of SMC sources classified with other methods, available in the literature. Carbon-rich Asymptotic Giant Branch (AGB) stars make up the majority (61%) of our variable sources, with about a third of all of our sources being classified as extreme AGB stars. We find a small, but significant population of oxygen-rich (O-rich) AGB (8.6%), Red Supergiant (2.8%), and Red Giant Branch (<1%) stars. Other matches to the literature include Cepheid variable stars (8.6%), early type stars (2.8%), Young-stellar objects (5.8%), and background galaxies (1.2%). We found a candidate OH maser star, SSTISAGE1C J005212.88-730852.8, which is a variable O-rich AGB star, and would be the first OH/IR star in the SMC, if confirmed. We measured the infrared variability of a rare RV Tau variable (a post-AGB star) that has recently left the AGB phase. 59 variable stars from our list remain unclassified.

  20. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01

    Dropsonde observations from the Bow-echo and Mesoscale convective vortex EXperiment (BAMEX) are used to document the spatio-temporal variability of temperature, moisture and wind within mesoscale convective systems (MCSs). Onion type sounding structures are found throughout the stratiform region of MCSs but the temperature and moisture variability is large. Composite soundings were constructed and statistics of thermodynamic variability were generated within each sub-region of the MCS. The calculated air vertical velocity helped identify subsaturated downdrafts. We found that lapse rates within the cold pool varied markedly throughout the MCS. Layered wet bulb potential temperature profiles seem to indicate that air within the lowest several km comes from a variety of source regions. We also found that lapse rate transitions across the 0 C level were more common than isothermal, melting layers. We discuss the implications these findings have and how they can be used to validate future high resolution numerical simulations of MCSs.