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Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Assessing the Energy Efficiency of Small Transit Systems; A Case Study of the Miami Metro Bus Service.  

E-Print Network (OSTI)

??In the recent past there has been an emphasis on energy and fuel efficiency in transit systems across the United States. Transit systems continue to… (more)

Kazungu, Conny Sidi

2012-01-01T23:59:59.000Z

2

First-principles transition-metal catalysis : efficient and accurate approaches for studying enzymatic systems  

E-Print Network (OSTI)

(cont.) We apply our approach to several paradigmatic systems: spin state splittings and structural properties of Fe2 and other small molecules as well as the addition-elimination reactions of hydrogen and methane on FeO+ ...

Kulik, Heather J

2009-01-01T23:59:59.000Z

3

Alternative Fuels Data Center: Transportation System Efficiency  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Transportation System Transportation System Efficiency to someone by E-mail Share Alternative Fuels Data Center: Transportation System Efficiency on Facebook Tweet about Alternative Fuels Data Center: Transportation System Efficiency on Twitter Bookmark Alternative Fuels Data Center: Transportation System Efficiency on Google Bookmark Alternative Fuels Data Center: Transportation System Efficiency on Delicious Rank Alternative Fuels Data Center: Transportation System Efficiency on Digg Find More places to share Alternative Fuels Data Center: Transportation System Efficiency on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework

4

Model Energy Conversion Efficiency of Biological Systems  

Science Conference Proceedings (OSTI)

MML Researchers Model Energy Conversion Efficiency of Biological Systems. Novel, highly efficient energy conversion ...

2013-03-15T23:59:59.000Z

5

Pump Systems Optimization: Energy Efficiency  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Pump Systems Pump Systems Optimization: Energy Efficiency and Bottom-Line Savings Host this one-day course to help participants learn how to identify and reduce hidden operation and energy costs. Participants will: * Identify energy savings * Increase profitability * Increase reliability * Earn seven PDH credits Attendees of the "Pump Systems Optimization" one-day course will gain valuable new skills to help them improve centrifugal pump system efficiency to reduce energy and operating costs while earning seven professional development hour (PDH) credits from the Hydraulic Institute. Topics covered include:* * Why Efficient Pump Systems Are Important

6

Pupillary efficient lighting system  

DOE Patents (OSTI)

A lighting system having at least two independent lighting subsystems each with a different ratio of scotopic illumination to photopic illumination. The radiant energy in the visible region of the spectrum of the lighting subsystems can be adjusted relative to each other so that the total scotopic illumination of the combined system and the total photopic illumination of the combined system can be varied independently. The dilation or contraction of the pupil of an eye is controlled by the level of scotopic illumination and because the scotopic and photopic illumination can be separately controlled, the system allows the pupil size to be varied independently of the level of photopic illumination. Hence, the vision process can be improved for a given level of photopic illumination. 5 figs.

Berman, S.M.; Jewett, D.L.

1989-04-14T23:59:59.000Z

7

Pupillary efficient lighting system  

DOE Patents (OSTI)

A lighting system having at least two independent lighting subsystems each with a different ratio of scotopic illumination to photopic illumination. The radiant energy in the visible region of the spectrum of the lighting subsystems can be adjusted relative to each other so that the total scotopic illumination of the combined system and the total photopic illumination of the combined system can be varied independently. The dilation or contraction of the pupil of an eye is controlled by the level of scotopic illumination and because the scotopic and photopic illumination can be separately controlled, the system allows the pupil size to be varied independently of the level of photopic illumination. Hence, the vision process can be improved for a given level of photopic illumination.

Berman, Samuel M. (San Francisco, CA); Jewett, Don L. (Mill Valley, CA)

1991-01-01T23:59:59.000Z

8

PERFORMANCE OF THE AGS TRANSITION JUMP SYSTEM.  

SciTech Connect

The transition jump system has been indispensable to the high intensity proton operation of the AGS complex. Nevertheless, transition crossing remains one of the major hurdles as the accelerator complex intensity is pushed upward. To enhance the performance of the system ''quadrupole pumping'' in the Booster is used to minimize the necessary longitudinal dilution of the beam on the AGS injection porch. During the transition jump sextupole correctors at strategic locations are pulsed to minimize the effects of the chromatic non-linearity of the jump system. The available instrumentation for diagnosing the performance of the system will be described, along with installed hardware to counter the non-linear effects of the transition jump system.

AHRENS,L.A.; BRENNAN,J.M.; GLENN,J.W.; ROSER,T.; VAN ASSELT,W.K.

1999-03-29T23:59:59.000Z

9

ENERGY EFFICIENT SYSTEM DESIGN AND UTILIZATION  

E-Print Network (OSTI)

. This model as- sumes that the decision to transition to low power state can be made in only one state model assumes that a decision to transition into a lower-power state can be made upon each event, the whole system, or some of its components can be transitioned into low-power states using dynamic power

Simunic, Tajana

10

Aruna Ravinagarajan System Energy Efficiency Lab  

E-Print Network (OSTI)

Aruna Ravinagarajan System Energy Efficiency Lab Aruna Ravinagarajan Advisor : Prof. Tajana Simunic of monitoring a structure over time and identifying damage System Energy Efficiency Lab damage A wireless sensor Efficiency Lab #12;SHM ­ How is it done?SHM ­ How is it done? System Energy Efficiency Lab Stuart G Taylor

11

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

resource/24/ ASHRAE handbook – HVAC systems and equipments.Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Efficient Cleanrooms Efficient HVAC Water Systems: Variable-

Xu, Tengfang

2005-01-01T23:59:59.000Z

12

Advanced Energy Efficient Roof System  

SciTech Connect

Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The options considered to date are not ideal. One approach is to insulate between the trusses at the roof plane. The construction process is time consuming and costs more than conventional attic construction. Moreover, the problems of air infiltration and thermal bridges across the insulation remain. Another approach is to use structurally insulated panels (SIPs), but conventional SIPs are unlikely to be the ultimate solution because an additional underlying support structure is required except for short spans. In addition, wood spline and metal locking joints can result in thermal bridges and gaps in the foam. This study undertook a more innovative approach to roof construction. The goal was to design and evaluate a modular energy efficient panelized roof system with the following attributes: (1) a conditioned and clear attic space for HVAC equipment and additional finished area in the attic; (2) manufactured panels that provide structure, insulation, and accommodate a variety of roofing materials; (3) panels that require support only at the ends; (4) optimal energy performance by minimizing thermal bridging and air infiltration; (5) minimal risk of moisture problems; (6) minimum 50-year life; (7) applicable to a range of house styles, climates and conditions; (8) easy erection in the field; (9) the option to incorporate factory-installed solar systems into the panel; and (10) lowest possible cost. A nationwide market study shows there is a defined market opportunity for such a panelized roof system with production and semi-custom builders in the United States. Senior personnel at top builders expressed interest in the performance attributes and indicate long-term opportunity exists if the system can deliver a clear value proposition. Specifically, builders are interested in (1) reducing construction cycle time (cost) and (2) offering increased energy efficiency to the homebuyer. Additional living space under the roof panels is another low-cost asset identified as part of the study. The market potential is enhanced through construction activity levels in target marke

Jane Davidson

2008-09-30T23:59:59.000Z

13

Geographic Information System At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

Geographic Information System At Walker-Lane Transitional Zone Region (Laney, 2005) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal Region Exploration...

14

Geographic Information System At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

Geographic Information System At Walker-Lane Transitional Zone Region (Coolbaugh, Et Al., 2005 - 2) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal...

15

Motor Systems Efficiency Supply Curves  

NLE Websites -- All DOE Office Websites (Extended Search)

expert opinion and available data from the United States, Canada, the European Union, Thailand, Vietnam, and Brazil, bottom-up energy efficiency supply curve models were...

16

Optical Transition Radiation System for ATF2  

SciTech Connect

In this paper we present the first measurements performed during the fall 2010 and early 2011 runs. Software development, simulations and hardware improvements to the Multi-Optical Transition Radiation System installed in the beam diagnostic section of the Extraction line of ATF2 are described. 2D emittance measurements have been performed and the system is being routinely used for coupling correction. Realistic beam simulations have been made and compared with the measurements. A demagnifier lens system to improve the beam finding procedure has been designed and will be implemented in a future run. We also discuss further work planned for the subsequent run periods.

Alabau-Gonzalvo, J.; Gutierrez, C.Blanch; Faus-Golfe, A.; Garcia-Garrigos, J.J.; /Valencia U., IFIC; Cruz, J.; McCormick, D.; White, G.; Woodley, M.; /SLAC

2012-02-14T23:59:59.000Z

17

Metadata Efficiency in Versioning File Systems  

Science Conference Proceedings (OSTI)

Versioning file systems retain earlier versions of modified files, allowing recovery from user mistakes or system corruption. Unfortunately, conventional versioning systems do not efficiently record large numbers of versions. In particular, versioned ...

Craig A. N. Soules; Garth R. Goodson; John D. Strunk; Gregory R. Ganger

2003-03-01T23:59:59.000Z

18

Metadata efficiency in versioning file systems  

Science Conference Proceedings (OSTI)

Versioning file systems retain earlier versions of modified files, allowing recovery from user mistakes or system corruption. Unfortunately, conventional versioning systems do not efficiently record large numbers of versions. In particular, versioned ...

Craig A. N. Soules; Garth R. Goodson; John D. Strunk; Gregory R. Ganger

2003-03-01T23:59:59.000Z

19

Rail Transit Investments, Real Estate Values, and Land Use Change: A Comparative Analysis of Five California Rail Transit Systems  

E-Print Network (OSTI)

Cervero, Robert. 1993. "Rail Transit and Joint Development:the Vancouver Advanced Light Rail Transit System on Single-Strathman. 1993. Light Rail Transit Stations and Property

Landis, John; Guhathakurta, Subhrajit; Huang, William; Zhang, Ming; Fukuji, Bruce

1995-01-01T23:59:59.000Z

20

Renewable and Efficient Electric Power Systems  

E-Print Network (OSTI)

.8.1 Ideal Transformers 37 1.8.2 Magnetization Losses 40 Problems 44 2 Fundamentals of Electric Power 51 2Renewable and Efficient Electric Power Systems Gilbert M. Masters Stanford University A JOHN WILEY & SONS, INC., PUBLICATION #12;#12;Renewable and Efficient Electric Power Systems #12;#12;Renewable

Kammen, Daniel M.

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Capitalization of Transit Investments into Single-Family Home Prices: A Comparative Analysis of Five California Rail Transit Systems  

E-Print Network (OSTI)

of the VancouverAdvancedLight Rail Transit System on Single-Analysis of Five California Rail Transit Systems John Lanchsof Five California Rail Transit Systems John Landis Subhra

Landis, John; Guhathakurta, Subhrajit; Zhang, Ming

1994-01-01T23:59:59.000Z

22

Ohio Transit System Saves With Solar | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ohio Transit System Saves With Solar Ohio Transit System Saves With Solar Ohio Transit System Saves With Solar July 23, 2010 - 3:42pm Addthis METRO Regional Transit Authority of Akron, OH is installing a solar energy system such as this on the central bus barn's roof. | Energy Department Photo | METRO Regional Transit Authority of Akron, OH is installing a solar energy system such as this on the central bus barn's roof. | Energy Department Photo | Joshua DeLung What does this project do? The new PV solar energy system being installed by the METRO Regional Transit Authority of Akron, Ohio on their central bus barn roof is expected to meet 15 percent of the transit system's bus barn energy needs. Akron, OH anticipates $40,000 in annual energy savings once the project is complete. Updated Oct. 13, 2010.

23

Improving Industrial Refrigeration System Efficiency - Actual Applications  

E-Print Network (OSTI)

This paper discusses actual design and modifications for increased system efficiency and includes reduced chilled liquid flow during part load operation, reduced condensing and increased evaporator temperatures for reduced system head, thermosiphon cycle cooling during winter operation, compressor intercooling, direct refrigeration vs. brine cooling, insulation of cold piping to reduce heat gain, multiple screw compressors for improved part load operation, evaporative condensers for reduced system head and pumping energy, and using high efficiency motors.

White, T. L.

1980-01-01T23:59:59.000Z

24

The Multi Optical Transition Radiation System  

SciTech Connect

The determination and monitoring of the transverse phase space in ATF2 is crucial in order to meet their performances specifications. Since the beam sizes at the Interaction Point (IP) depend strongly on the aberrations in the Final Focus System (FFS), accurate measurement upstream of the FFS is required to tune the beam sizes at the IP. The beam sizes as well as the emittance are measured in several locations in the beam diagnostic section of the Extraction Line (EXT line) of ATF2. The vertical beam sizes in the diagnostic section are of the order of 10 {mu}m this means that the devices have to image spot sizes as small as 5 {mu}m, with 10% accuracy a 2 {mu}m resolution device is necessary. The ATF2 EXT line is a beam line with low power and low repetition rate that make usable devices using solid targets. In contrast to a ring machine, where an individual bunch can be measured many times as it passes around the ring, the beam size and the emittance measurement in the LC or in the beam lines have to be performed in a single pass. This requires that the wire scan device types (laser or solid) sample across successive bunches within a train, often with an over-estimation of the beam size due to beam position and intensity jitter, and can take up to half a minute to complete the measurement. Although some of these effects could be corrected, as the jitter effect could be subtracted by using the nearby BPMs signals, this can be avoided by using Optical Transition Radiation (OTR) Monitors. These monitors are based on the transition radiation effect, a light cone emitted when the charged particle crosses a metallic interface. This light is emitted in a specular fashion so it can be focused on to a CCD and produces an image of the beam. OTRs are able to take many fast measurements and therefore to measure the emittance with high statistics, giving a low error and a good understanding of the emittance jitter. In this article, simulations of the expected beam sizes and emittance, along with a technical description of the system, its hardware and software implementation are described. Additionally first measurement of the beam size and emittance of the Multi Optical Transition Radiation System located in the Extraction Line of ATF2 are presented.

Faus-Golfe, A.; Alabau-Gonzalvo, J.; Blanch Gutierrez, C.; /Valencia U., IFIC; McCormick, D.; Cruz, J.; Woodley, M.; White, G.; /SLAC

2012-04-19T23:59:59.000Z

25

System strategies in the management of transit systems towards the end of their life cycle  

E-Print Network (OSTI)

This thesis explores and evaluates essential strategies needed for the transit authority/operator to deal with end of life cycle challenges of Rapid Transit Systems (RTS) systems. RTS systems are elaborate systems consisting ...

Kairon, Ajmer Singh

2007-01-01T23:59:59.000Z

26

Geographic Information System At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geographic Information System At Walker-Lane Transitional Zone Region (Blackwell, Et Al., 2003)...

27

Energy efficiency improvements in Chinese compressed air systems  

E-Print Network (OSTI)

Air Systems, Paper #071 Energy efficiency improvements into increase industrial energy efficiency. As a result, morein use. Over time, energy efficiency decreases and the cost

McKane, Aimee; Li, Li; Li, Yuqi; Taranto, T.

2008-01-01T23:59:59.000Z

28

Quantum phase transitions in Bose-Fermi systems  

SciTech Connect

Research Highlights: > We study quantum phase transitions in a system of N bosons and a single-j fermion. > Classical order parameters and correlation diagrams of quantum levels are determined. > The odd fermion strongly influences the location and nature of the phase transition. > Experimental evidence for the U(5)-SU(3) transition in odd-even nuclei is presented. - Abstract: Quantum phase transitions in a system of N bosons with angular momentum L = 0, 2 (s, d) and a single fermion with angular momentum j are investigated both classically and quantum mechanically. It is shown that the presence of the odd fermion strongly influences the location and nature of the phase transition, especially the critical value of the control parameter at which the phase transition occurs. Experimental evidence for the U(5)-SU(3) (spherical to axially-deformed) transition in odd-even nuclei is presented.

Petrellis, D., E-mail: dimitris.petrellis@yale.edu [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States); Leviatan, A., E-mail: ami@phys.huji.ac.il [Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel); Iachello, F., E-mail: francesco.iachello@yale.edu [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States)

2011-04-15T23:59:59.000Z

29

Leaf seal for transition duct in turbine system  

DOE Patents (OSTI)

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a leaf seal contacting the interface member to provide a seal between the interface member and the turbine section.

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

2013-06-11T23:59:59.000Z

30

Efficient identification of exoplanetary transit candidates from SuperWASP light curves  

E-Print Network (OSTI)

Transiting extrasolar planets constitute only a small fraction of the range of stellar systems found to display periodic, shallow dimmings in wide-field surveys employing small-aperture camera arrays. Here we present an efficient selection strategy for follow-up observations, derived from analysis of the light curves of a sample of 67 SuperWASP targets that passed the selection tests we used in earlier papers, but which have subsequently been identified either as planet hosts or as astrophysical false positives. We determine the system parameters using Markov-chain Monte Carlo analysis of the SuperWASP light curves. We use a constrained optimisation of chi-squared combined with a Bayesian prior based on the main-sequence mass and radius expected from the 2MASS J-H colour. The Bayesian nature of the analysis allows us to quantify both the departure of the host star from the main-sequence mass-radius relation and the probability that the companion radius is less than 1.5 Jupiter radii. When augmented by direct ...

Cameron, A Collier; West, R G; Hebb, L; Wang, X -B; Aigrain, S; Bouchy, F; Christian, D J; Clarkson, W I; Enoch, B; Esposito, M; Günther, E; Haswell, C A; Hébrard, G; Hellier, C; Horne, K; Irwin, J; Kane, S R; Loeillet, B; Lister, T A; Maxted, P; Mayor, M; Moutou, C; Parley, N; Pollacco, D; Pont, F; Queloz, D; Ryans, R; Skillen, I; Street, R A; Udry, S; Wheatley, P J

2007-01-01T23:59:59.000Z

31

Industrial Compressed Air System Energy Efficiency Guidebook.  

DOE Green Energy (OSTI)

Energy efficient design, operation and maintenance of compressed air systems in industrial plants can provide substantial reductions in electric power and other operational costs. This guidebook will help identify cost effective, energy efficiency opportunities in compressed air system design, re-design, operation and maintenance. The guidebook provides: (1) a broad overview of industrial compressed air systems, (2) methods for estimating compressed air consumption and projected air savings, (3) a description of applicable, generic energy conservation measures, and, (4) a review of some compressed air system demonstration projects that have taken place over the last two years. The primary audience for this guidebook includes plant maintenance supervisors, plant engineers, plant managers and others interested in energy management of industrial compressed air systems.

United States. Bonneville Power Administration.

1993-12-01T23:59:59.000Z

32

Energy Transitions: A Systems Approach Including Marcellus Shale Gas Development  

E-Print Network (OSTI)

Energy Transitions: A Systems Approach Including Marcellus Shale Gas Development A Report Transitions: A Systems Approach Including Marcellus Shale Gas Development Executive Summary In the 21st the Marcellus shale In addition to the specific questions identified for the case of Marcellus shale gas in New

Angenent, Lars T.

33

Improving energy efficiency: Strategies for supporting sustained market evolution in developing and transitioning countries  

SciTech Connect

This report presents a framework for considering market-oriented strategies for improving energy efficiency that recognize the conditions of developing and transitioning countries, and the need to strengthen the effectiveness of market forces in delivering greater energy efficiency. It discusses policies that build markets in general, such as economic and energy pricing reforms that encourage competition and increase incentives for market actors to improve the efficiency of their energy use, and measures that reduce the barriers to energy efficiency in specific markets such that improvement evolves in a dynamic, lasting manner. The report emphasizes how different policies and measures support one another and can create a synergy in which the whole is greater than the sum of the parts. In addressing this topic, it draws on the experience with market transformation energy efficiency programs in the US and other industrialized countries.

Meyers, S.

1998-02-01T23:59:59.000Z

34

Demand-Responsive and Efficient Building Systems as a Resource...  

NLE Websites -- All DOE Office Websites (Extended Search)

Demand-Responsive and Efficient Building Systems as a Resource for Electricity Reliability Title Demand-Responsive and Efficient Building Systems as a Resource for Electricity...

35

Building Technologies Office: Highly Energy Efficient Wall Systems...  

NLE Websites -- All DOE Office Websites (Extended Search)

Highly Energy Efficient Wall Systems Research Project to someone by E-mail Share Building Technologies Office: Highly Energy Efficient Wall Systems Research Project on Facebook...

36

Motor System Energy Efficiency Supply Curves: A Methodology for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Motor System Energy Efficiency Supply Curves: A Methodology for Assessing the Energy Efficiency Potential of Industrial Motor Systems Speaker(s): Ali Hasanbeigi Date: February 8,...

37

Exploring Efficient Data Movement Strategies for Exascale Systems...  

NLE Websites -- All DOE Office Websites (Extended Search)

Exploring Efficient Data Movement Strategies for Exascale Systems with Deep Memory Hierarchies Exploring Efficient Data Movement Strategies for Exascale Systems with Deep Memory...

38

Solar ADEPT: Efficient Solar Energy Systems  

DOE Green Energy (OSTI)

Solar ADEPT Project: The 7 projects that make up ARPA-E's Solar ADEPT program, short for 'Solar Agile Delivery of Electrical Power Technology,' aim to improve the performance of photovoltaic (PV) solar energy systems, which convert the sun's rays into electricity. Solar ADEPT projects are integrating advanced electrical components into PV systems to make the process of converting solar energy to electricity more efficient.

None

2011-01-01T23:59:59.000Z

39

Energy Efficient Operation of Ammonia Refrigeration Systems  

SciTech Connect

Ammonia refrigeration systems typically offer many energy efficiency opportunities because of their size and complexity. This paper develops a model for simulating single-stage ammonia refrigeration systems, describes common energy saving opportunities, and uses the model to quantify those opportunities. The simulation model uses data that are typically available during site visits to ammonia refrigeration plants and can be calibrated to actual consumption and performance data if available. Annual electricity consumption for a base-case ammonia refrigeration system is simulated. The model is then used to quantify energy savings for six specific energy efficiency opportunities; reduce refrigeration load, increase suction pressure, employ dual suction, decrease minimum head pressure set-point, increase evaporative condenser capacity, and reclaim heat. Methods and considerations for achieving each saving opportunity are discussed. The model captures synergistic effects that result when more than one component or parameter is changed. This methodology represents an effective method to model and quantify common energy saving opportunities in ammonia refrigeration systems. The results indicate the range of savings that might be expected from common energy efficiency opportunities.

Mohammed, Abdul Qayyum [University of Dayton, Ohio; Wenning, Thomas J [ORNL; Sever, Franc [University of Dayton, Ohio; Kissock, Professor Kelly [University of Dayton, Ohio

2013-01-01T23:59:59.000Z

40

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

LBNL-58636 Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable Efficient Cleanrooms Efficient HVAC Water Systems: Variable-Speed-Drive Chillers Tengfang Xu Contents HVAC.................................................................................................................................... 6 #12;HVAC Water Systems Variable-Speed-Drive Chillers Summary Cleanroom energy benchmarking data

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Transmission System Efficiency Technology and Methodology Assessment  

Science Conference Proceedings (OSTI)

Reducing the carbon footprint of the electric power industry and increasing the role of renewable energy are crucial parts of a strategy for the greening of electric energy supply. This work describes the technological options available to reduce losses in transmission systems. It presents a comprehensive framework that can be applied consistently and uniformly to all energy efficiency demonstration projects to identify and quantify the various types of benefits in a standardized manner. The framework id...

2010-12-15T23:59:59.000Z

42

Efficient identification of exoplanetary transit candidates from SuperWASP light curves  

E-Print Network (OSTI)

Transiting extrasolar planets constitute only a small fraction of the range of stellar systems found to display periodic, shallow dimmings in wide-field surveys employing small-aperture camera arrays. Here we present an efficient selection strategy for follow-up observations, derived from analysis of the light curves of a sample of 67 SuperWASP targets that passed the selection tests we used in earlier papers, but which have subsequently been identified either as planet hosts or as astrophysical false positives. We determine the system parameters using Markov-chain Monte Carlo analysis of the SuperWASP light curves. We use a constrained optimisation of chi-squared combined with a Bayesian prior based on the main-sequence mass and radius expected from the 2MASS J-H colour. The Bayesian nature of the analysis allows us to quantify both the departure of the host star from the main-sequence mass-radius relation and the probability that the companion radius is less than 1.5 Jupiter radii. When augmented by direct light curve analyses that detect binaries with unequal primary and secondary eclipses, and objects with aperture blends that are resolved by SuperWASP, we find that only 13 of the original 67 stars, including the three known planets in the sample, would qualify for follow-up. This suggests that planet discovery "hit rates" better than one-in-five should be achievable. In addition, the stellar binaries that qualify are likely to have astrophysically interesting stellar or sub-stellar secondaries.

A. Collier Cameron; D. M. Wilson; R. G. West; L. Hebb; X. -B. Wang; S. Aigrain; F. Bouchy; D. J. Christian; W. I. Clarkson; B. Enoch; M. Esposito; E. Guenther; C. A. Haswell; G. Hebrard; C. Hellier; K. Horne; J. Irwin; S. R. Kane; B. Loeillet; T. A. Lister; P. Maxted; M. Mayor; C. Moutou; N. Parley; D. Pollacco; F. Pont; D. Queloz; R. Ryans; I. Skillen; R. A. Street; S. Udry; P. J. Wheatley

2007-07-03T23:59:59.000Z

43

Aromaticity and Antiaromaticity in Transition-Metal Systems  

SciTech Connect

Aromaticity is an important concept in chemistry primarily for hydrocarbon compounds, but it has been extended to compounds containing transition-metal atoms. Recent findings of aromaticity and antiaromaticy in all-metal clusters have stimulated further researches in describing the chemical bonding, structures, and stability in transition-metal clusters and compounds on the basis of aromaticity and antiaromaticity, which are reviewed here. The presence of d-orbitals endows much more diverse chemistry, structure, and chemical bonding to transition-metal clusters and compounds. One interesting feature is the existence of a new type of ?-aromaticity, in addition to ?- and ?-aromaticity that are only possible for main group compounds. Another striking characteristic in the chemical bonding of transition-metal systems is the multi-fold nature of aromaticity, antiaromaticity, or even conflicting aromaticity. Separate sets of counting rules have been proposed for cyclic transition-metal systems to account for the three types of ?-, ?-, and ?-aromaticity/antiaromaticity. The diverse transition-metal clusters and compounds reviewed here indicate that multiple aromaticity and antiaromaticity may be much more common in chemistry than one would anticipate. It is hoped that the current review will stimulate interest in further understanding the structure and bonding, on the basis of aromaticity and antiaromaticity, of other known or unknown transition-metal systems, such as the active sites of enzymes or other biomolecules, which contain transition-metal atoms and clusters.

Zubarev, Dmitry Y.; Averkiev, Boris B.; Zhai, Hua Jin; Wang, Lai S.; Boldyrev, Alexander I.

2008-01-14T23:59:59.000Z

44

Geographic Information System At Walker-Lane Transitional Zone Region  

Open Energy Info (EERE)

Walker-Lane Transitional Zone Region Walker-Lane Transitional Zone Region (Blackwell, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geographic Information System At Walker-Lane Transitional Zone Region (Blackwell, Et Al., 2003) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal Region Exploration Technique Geographic Information System Activity Date Usefulness useful DOE-funding Unknown Notes Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dixie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems References D. D. Blackwell, K. W. Wisian, M. C. Richards, Mark Leidig, Richard

45

Advanced Systems of Efficient Use of Electrical Energy SURE ...  

Open Energy Info (EERE)

of Efficient Use of Electrical Energy SURE (Smart Grid Project) Jump to: navigation, search Project Name Advanced Systems of Efficient Use of Electrical Energy SURE Country...

46

Energy efficiency of a dynamic glazing system  

SciTech Connect

The reduction of air-conditioning energy consumptions is one of the main indicators to act on when improving the energy efficiency in buildings. In the case of advanced technological buildings, a meaningful contribution to the thermal loads and the energy consumptions reduction could depend on the correct configuration and management of the envelope systems. In recent years, the architectural trend toward highly transparent all-glass buildings presents a unique challenge and opportunity to advance the market for emerging, smart, dynamic window and dimmable daylighting control technologies (). A prototype dynamic glazing system was developed and tested at ITC-CNR; it is aimed at actively responding to the external environmental loads. Both an experimental campaign and analyses by theoretical models were carried out, aimed at evaluating the possible configurations depending on different weather conditions in several possible places. Therefore, the analytical models of the building-plant system were defined by using a dynamic energy simulation software (EnergyPlus). The variables that determine the system performance, also influenced by the boundary conditions, were analysed, such as U- and g-value; they concern both the morphology of the envelope system, such as dimensions, shading and glazing type, gap airflow thickness, in-gap airflow rate, and management, in terms of control algorithm parameters tuning fan and shading systems, as a function of the weather conditions. The configuration able to provide the best performances was finally identified by also assessing such performances, integrating the dynamic system in several building types and under different weather conditions. The dynamic envelope system prototype has become a commercial product with some applications in facade systems, curtain walls and windows. The paper describes the methodological approach to prototype development and the main results obtained, including simulations of possible applications on real buildings. (author)

Lollini, R. [Institute for Renewable Energy, EURAC Research, Viale Druso 1, I-39100 Bolzano (Italy); Danza, L.; Meroni, I. [ITC-CNR, Construction Technologies Institute - Italian National Research Council, Via Lombardia, 49 - 20098 San Giuliano Milanese (MI) (Italy)

2010-04-15T23:59:59.000Z

47

Agentc: Agent-based system for securing maritime transit  

E-Print Network (OSTI)

Recent rise in maritime piracy prompts the search for novel techniques for addressing the problem. We therefore developed AgentC, a prototype system that demonstrates how agent-based traffic management techniques can be used to improve the security of transit through piracy-affected areas. Combining agent-based modeling and simulation of maritime traffic and novel route planning and vessel scheduling techniques, the system shows the promising potential of agent-based methods for increasing maritime security. Real-world data sources Control and presentation interface (Google Earth) Route planning and scheduling Optimum group transit formation Maritime traffic simulation Maritime environment model Randomized transit routing FSM-based vessel behavior models Optimum transit patrolling Inter-agent communication channels

Michal Jakob; Branislav Bošanský; Michal P?chou?ek

2011-01-01T23:59:59.000Z

48

The Dynamics of Air Transportation System Transition  

E-Print Network (OSTI)

Both U.S. and European Air Transportation Systems face substantial challenges in transforming to meet future demand. This paper uses a feedback model to identify

Mozdzanowska, Aleksandra

49

A Taxonomy and Survey of Energy-Efficient Data Centers and Cloud Computing Systems  

E-Print Network (OSTI)

efficiently · Reduce he transition overhead caused by switching between different power states and VM is independent of clock rates, device usage scenarios and system status, for example, the leakage power, Power Supply... interact with ACPI-compliant OS through AML(ACPI machine Language) · Global states

Lu, Ying

50

Feedback damper system for quadrupole oscillations after transition at RHIC.  

Science Conference Proceedings (OSTI)

The heavy ion beam at RHIC undergoes strong quadrupole oscillations just after it crosses transition, which leads to an increase in bunch length making rebucketing less effective. A feedback system was built to damp these quadrupole oscillations and in this paper the characteristics of the system and the results obtained are presented and discussed.

Abreu,N.; Blaskiewicz, M.; Brennan, J.M.; Schultheiss, C.

2008-06-23T23:59:59.000Z

51

Energy Transitions: A Systems Approach Including Marcellus Shale Gas Development  

E-Print Network (OSTI)

Energy Transitions: A Systems Approach Including Marcellus Shale Gas Development A Report: A Systems Approach Including Marcellus Shale Gas Development Executive Summary In the 21st century new we focused on the case of un- conventional natural gas recovery from the Marcellus shale In addition

Walter, M.Todd

52

Quantum-"classical" correspondence in a nonadiabatic-transition system  

E-Print Network (OSTI)

A nonadiabatic-transition system which exhibits ``quantum chaotic'' behavior [Phys. Rev. E {\\bf 63}, 066221 (2001)] is investigated from quasi-classical aspects. Since such a system does not have a naive classical limit, we take the mapping approach by Stock and Thoss [Phys. Rev. Lett. {\\bf 78}, 578 (1997)] to represent the quasi-classical dynamics of the system. We numerically show that there is a sound correspondence between the quantum chaos and classical chaos for the system.

Fujisaki, H

2004-01-01T23:59:59.000Z

53

Quantum-"classical" correspondence in a nonadiabatic-transition system  

E-Print Network (OSTI)

A nonadiabatic-transition system which exhibits ``quantum chaotic'' behavior [Phys. Rev. E {\\bf 63}, 066221 (2001)] is investigated from quasi-classical aspects. Since such a system does not have a naive classical limit, we take the mapping approach by Stock and Thoss [Phys. Rev. Lett. {\\bf 78}, 578 (1997)] to represent the quasi-classical dynamics of the system. We numerically show that there is a sound correspondence between the quantum chaos and classical chaos for the system.

Hiroshi Fujisaki

2004-01-22T23:59:59.000Z

54

Algorithmic entropy, phase transition, and smart systems  

Science Conference Proceedings (OSTI)

A smart system exhibits the three important properties: (i) interactive, collective, coordinated and parallel operation (ii) self-organization through emergent properties (iii) adaptive and flexible operation. A hierarchy based on metric entropy is suggested ...

E. V. Krishnamurthy

2003-06-01T23:59:59.000Z

55

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

E-Print Network (OSTI)

Comparison of energy efficiency between variable refrigeranttheir superior energy efficiency. The variable refrigerantfew studies reporting the energy efficiency of VRF systems

Hong, Tainzhen

2010-01-01T23:59:59.000Z

56

Transitioning to Biofuels: A System-of-Systems Perspective; Preprint  

DOE Green Energy (OSTI)

Using the existing fuel supply chain infrastructure as a framework, this paper discusses a vision for transitioning to a larger biofuels industry and the challenges associated with a massive market and infrastructure transformation.

Riley, C.; Sandor, D.

2008-06-01T23:59:59.000Z

57

Efficient thermal management for multiprocessor systems  

E-Print Network (OSTI)

2.2.4 Thermal Modeling . . . . . . . .63 Table 4.3: Thermal Hot Spots . . . . . . . . . . . . . .Performance-Efficient Thermal Management . . . . . . . . . .

Co?kun, Ay?e K?v?lc?m

2009-01-01T23:59:59.000Z

58

Geographic Information System At Walker-Lane Transitional Zone Region  

Open Energy Info (EERE)

Geographic Information System At Walker-Lane Geographic Information System At Walker-Lane Transitional Zone Region (Laney, 2005) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal Region Exploration Technique Geographic Information System Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown Notes Regional Assessment of Exploration Potential for Geothermal Systems in The Great Basin Using a Geographic Information System (GIS) - Part II, Coolbaugh, Zehner, Raines, Shevenell, Minor, Sawatzky and Oppliger. The objective is to generate new exploration targets for both conventional and EGS capable geothermal systems by analyzing regional data in a GIS. Digital geothermal data will be made available to industry and researchers on a web site. Relationships among the data will be explored using spatial

59

Efficient Bayesian estimation of Markov model transition matrices with given stationary distribution  

E-Print Network (OSTI)

Direct simulation of biomolecular dynamics in thermal equilibrium is challenging due to the metastable nature of conformation dynamics and the computational cost of molecular dynamics. Biased or enhanced sampling methods may improve the convergence of expectation values of equilibrium probabilities and expectation values of stationary quantities significantly. Unfortunately the convergence of dynamic observables such as correlation functions or timescales of conformational transitions relies on direct equilibrium simulations. Markov state models are well suited to describe both, stationary properties and properties of slow dynamical processes of a molecular system, in terms of a transition matrix for a jump process on a suitable discretiza- tion of continuous conformation space. Here, we introduce statistical estimation methods that allow a priori knowledge of equilibrium probabilities to be incorporated into the estimation of dynamical observables. Both, maximum likelihood methods and an improved Monte Carlo sampling method for reversible transition ma- trices with fixed stationary distribution are given. The sampling approach is applied to a toy example as well as to simulations of the MR121-GSGS-W peptide, and is demonstrated to converge much more rapidly than a previous approach in [F. Noe, J. Chem. Phys. 128, 244103 (2008)

Benjamin Trendelkamp-Schroer; Frank Noe

2013-01-10T23:59:59.000Z

60

Pulp and Paper Mills: Profiting for Efficient Motor System Use...  

NLE Websites -- All DOE Office Websites (Extended Search)

Motor System Use This profile discusses how energy efficienct motor systems can help pulp and paper mills save money. Pulp and Paper Mills: Profiting for Efficient Motor System Use...

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Efficiency of Steam and Hot Water Heat Distribution Systems  

E-Print Network (OSTI)

Efficiency of Steam and Hot Water Heat Distribution Systems Gary Phetteplace September 1995- tion medium (steam or hot water) and temperature for heat distribution systems. The report discusses the efficiency of both steam and hot water heat distribution systems in more detail. The results of several field

62

Energy efficiency strategies in refrigeration systems of large supermarkets  

Science Conference Proceedings (OSTI)

Energy efficiency and its relationship with sustainable development are one of the most important objectives in modern engineering systems. In Industrial Installations that use refrigeration systems that are associated with the food industry, this optimization ... Keywords: energy efficiency, optimizing parameters, refrigeration systems, supermarkets

J. M. Garcia; L. M. R. Coelho

2010-07-01T23:59:59.000Z

63

Increase energy efficiency in systems and buildings and improve...  

NLE Websites -- All DOE Office Websites (Extended Search)

Increase energy efficiency in systems and buildings and improve indoor environment: How to validate comfort and energy reduction Speaker(s): Wouter Borsboom Date: December 8, 2009...

64

Energy Efficiency Labeling System & its Development in China  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Labeling Labeling System & Its Development in China Cheng Jianhong Berkeley, U.S. 6 May, 2011 The Second U.S.-China Energy Efficiency Forum  Initiated in 2005 The issue of Measures for the Administration of Energy Efficiency Labels ([2004] Decree No. 17) by NDRC and AQSIQ marked that energy efficiency labeling system was formally established in China. I. Concept of Energy Efficiency Labels in China Positive externalities of energy conservation management Dissymmetry of energy efficiency information Disclosure of energy efficiency information Supervision over information authenticity Essence of energy efficiency labeling system 10 One of the Tools for Market Transformation Energy Conservation Law Product Quality Law Regulations of the People's Republic of China on Certification

65

Transition to a nuclear/hydrogen energy system.  

DOE Green Energy (OSTI)

The paper explores the motivation for the transition to a nuclear/hydrogen system. For such a transition to be successful the technologies employed must be able to generate enough hydrogen to displace a significant fraction of the petroleum fuels used in the transportation and process heat sectors. This hydrogen must be generated in a manner that is compatible with the environment and independent of foreign fuels. Nuclear energy, along with contributions from wind, solar, and geothermal resources meet the criteria of environmental compatibility and resource independence. However, nuclear energy is the only one of these sources that has a high enough energy density to generate copious quantities of hydrogen. The status of the relevant nuclear and hydrogen technologies are discussed and how they are coupled to bring about a transition to a nuclear/hydrogen system. Should the world adopt such a system then the growth rate of nuclear energy would greatly accelerate. With an accelerated growth for nuclear energy the uranium resources would be depleted in a few decades with the once through fuel cycle currently in use. It is pointed out that deployment of fast breeder reactors would become important in the nearer term.

Walters, L.; Wade, D.; Lewis, D.

2002-08-13T23:59:59.000Z

66

Energy-efficient lighting system for television  

DOE Patents (OSTI)

A light control system for a television camera comprises an artificial light control system which is cooperative with an iris control system. This artificial light control system adjusts the power to lamps illuminating the camera viewing area to provide only sufficient artificial illumination necessary to provide a sufficient video signal when the camera iris is substantially open.

Cawthorne, Duane C. (Amarillo, TX)

1987-07-21T23:59:59.000Z

67

Highly Energy Efficient Wall Systems Research Project | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Highly Energy Efficient Wall Systems Highly Energy Efficient Wall Systems Research Project Highly Energy Efficient Wall Systems Research Project The Department of Energy is currently conducting research into highly energy efficient wall systems. Walls with high R-values are better insulators, and their development can help buildings come closer to having zero net energy consumption. Project Description This project seeks to develop a commercially viable wall system up to R-40 through integration of vacuum technology with the exterior insulated façade system (EIFS). Dow Corning will develop a wall system configuration of expanded polystyrene vacuum isolation panels that can be specified for R-values of 20, 30, and 40. This project also aims to develop a unitized protection system of vacuum isolation panels and to validate current code

68

Klystron "efficiency loop" for the ALS storage ring RF system  

E-Print Network (OSTI)

EFFICIENCY LOOP” FOR THE ALS STORAGE RING RF SYSTEM* S.at the Advanced Light Source (ALS) in order to decrease thethe cavities. 1 INTRODUCTION ALS Storage Ring RF system is

Kwiatkowski, Slawomir; Julian, Jim; Baptiste, Kenneth

2002-01-01T23:59:59.000Z

69

Power-efficient time-sensitive mapping in heterogeneous systems  

Science Conference Proceedings (OSTI)

Heterogeneous systems that contain multiple types of resources, such as CPUs and GPUs, are becoming increasingly popular thanks to the potential of achieving high performance and energy efficiency. In such systems, the problem of data mapping and communication ... Keywords: heterogeneous cpu/gpu multiprocessors, multi-core architectures, power-efficient scheduling

Cong Liu; Jian Li; Wei Huang; Juan Rubio; Evan Speight; Xiaozhu Lin

2012-09-01T23:59:59.000Z

70

AN ENERGY EFFICIENT WINDOW SYSTEM FINAL REPORT.  

E-Print Network (OSTI)

greenhouses, passive solar heating and other non-viewingpassive and active solar heating systems. the fact remainsthe expense of winter solar heating), Life Cycle Costing We

Authors, Various

2011-01-01T23:59:59.000Z

71

Scalable and Energy Efficient Computer Systems - Energy ...  

Technology Marketing Summary Computer engineers have developed a new design to support construction of large computer systems that perform closer to ...

72

Highly Efficient Electric Motor Systems - National Renewable ...  

Electric Motor Systems ... savings. Conical hubs Matching axial field poles. Issued Patents on Motor Geometry. 7 NREL Energy Forum November 2009 www.novatorque.com.

73

Improving Energy Efficiency of Compressed Air System Based on System Audit  

E-Print Network (OSTI)

plan, formulate energy efficiency goals and adopt energyGO-102004-1926 [3] Energy Efficiency and Market Potential ofImproving Energy Efficiency of Compressed Air System Based

Shanghai, Hongbo Qin; McKane, Aimee

2008-01-01T23:59:59.000Z

74

Communication architecture based power management for battery efficient system design  

Science Conference Proceedings (OSTI)

Communication-based power management (CBPM) is a new battery-driven system-level power management methodology in which the system-level communication architecture regulates the execution of various system components, with the aim of improving battery ... Keywords: battery efficiency, communication architectures, embedded systems, low power design, power management

Kanishka Lahiri; Sujit Dey; Anand Raghunathan

2002-06-01T23:59:59.000Z

75

Energy-efficient lighting system for television  

DOE Patents (OSTI)

A light control system for a television camera which adjusts the power to lamps illuminating the camera viewing area to provide only sufficient artificial illumination necessary to keep the camera iris substantially open is described.

Cawthorne, D.C.

1986-01-29T23:59:59.000Z

76

Efficient design methods for embedded communication systems  

Science Conference Proceedings (OSTI)

Nowadays, design of embedded systems is confronted with complex signal processing algorithms and a multitude of computational intensive multimedia applications, while time to product launch has been extremely reduced. Especially in the wireless domain, ...

M. Holzer; B. Knerr; P. Belanovi?; M. Rupp

2006-01-01T23:59:59.000Z

77

EVIDENCE OF POSSIBLE SPIN-ORBIT MISALIGNMENT ALONG THE LINE OF SIGHT IN TRANSITING EXOPLANET SYSTEMS  

SciTech Connect

Of the 26 transiting exoplanet systems with measurements of the Rossiter-McLaughlin (RM) effect, eight have now been found to be significantly spin-orbit misaligned in the plane of the sky (i.e., RM misalignment angle |{lambda}| {approx}> 30{sup 0} and inconsistent with {lambda} = 0{sup 0}). Unfortunately, the RM effect does not constrain the complement misalignment angle between the orbit of the planet and the spin of its host star along the line of sight (LOS). I use a simple model of stellar rotation benchmarked with observational data to statistically identify 10 exoplanet systems from a sample of 75 for which there is likely a significant degree of spin-orbit misalignment along the LOS: HAT-P-7, HAT-P-14, HAT-P-16, HD 17156, Kepler-5, Kepler-7, TrES-4, WASP-1, WASP-12, and WASP-14. All 10 systems have host stellar masses M {sub *} in the range 1.2 M {sub sun} {approx}< M {sub *} {approx}< 1.5 M {sub sun}, and the probability of this occurrence by chance is less than one in ten thousand. In addition, the planets in the candidate-misaligned systems are preferentially massive and eccentric. The coupled distribution of misalignment from the RM effect and from this analysis suggests that transiting exoplanets are more likely to be spin-orbit aligned than expected given predictions for a transiting planet population produced entirely by planet-planet scattering or Kozai cycles and tidal friction. For that reason, there are likely two populations of close-in exoplanet systems: a population of aligned systems and a population of apparently misaligned systems in which the processes that lead to misalignment or to the survival of misaligned systems operate more efficiently in systems with massive stars and planets.

Schlaufman, Kevin C., E-mail: kcs@ucolick.or [Astronomy and Astrophysics Department, University of California, Santa Cruz, CA 95064 (United States)

2010-08-10T23:59:59.000Z

78

Toward green systems for cleanrooms: Energy efficient fan-filter units  

E-Print Network (OSTI)

filter unit (FFU), energy efficiency, green system, electricToward Green Systems for Cleanrooms: Energy Efficient Fan-energy efficient models; Market transformation toward “green”

Jeng, Ming-Shan; Xu, Tengfang; Lan, Chao-Ho

2004-01-01T23:59:59.000Z

79

Energy Efficiency in Compressed Air Systems  

E-Print Network (OSTI)

Energy use in compressed air systems accounts for typically 10% of the total industrial electricity consumption. It also accounts for close to 99% of the CO2 footprint of an air compressor and approximately 80% of the life cycle costs of a compressor, over its lifetime. Considering these facts, it is sometimes surprising to see the lack of attention to compressed air systems in industry. This paper attempts to create awareness as to how a great deal of energy can be saved through a conscious process of selection and use of compressed air systems, bringing substantial benefits in economics and the environment. It also attempts to highlight the relative importance of energy savings over the costs of investments made in energy saving features and processes.

Hingorani, A.; Pavlov, A.

2010-01-01T23:59:59.000Z

80

Secure and Efficient Routable Control Systems  

SciTech Connect

This document provides the methods to secure routable control system communication in the electric sector. The approach of this document yields a long-term vision for a future of secure communication, while also providing near term steps and a roadmap. The requirements for the future secure control system environment were spelled out to provide a final target. Additionally a survey and evaluation of current protocols was used to determine if any existing technology could achieve this goal. In the end a four-step path was described that brought about increasing requirement completion and culminates in the realization of the long term vision.

Edgar, Thomas W.; Hadley, Mark D.; Manz, David O.; Winn, Jennifer D.

2010-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Symmetry Reduction for SAT Representations of Transition Systems Jussi Rintanen  

E-Print Network (OSTI)

the symmetric states at given time points, but to order the sequences of transitions. Tran- sition sequences can be eliminated by order- ing transition sequences, as transition relations that are not symmetric in some states from transition sequences also removes all sym- metry from the sequences of states these sequences

Nebel, Bernhard

82

Implementation and Rejection of Industrial Steam System Energy Efficiency  

NLE Websites -- All DOE Office Websites (Extended Search)

Implementation and Rejection of Industrial Steam System Energy Efficiency Implementation and Rejection of Industrial Steam System Energy Efficiency Measures Title Implementation and Rejection of Industrial Steam System Energy Efficiency Measures Publication Type Journal Article Refereed Designation Unknown LBNL Report Number LBNL-6288E Year of Publication 2013 Authors Therkelsen, Peter L., and Aimee T. McKane Journal Energy Policy Volume 57 Start Page 318 Date Published 06/2013 Publisher Lawrence Berkeley National Laboratory Keywords industrial energy efficiency, industrial energy efficiency barriers, steam system efficiency Abstract Steam systems consume approximately one third of energy applied at U.S. industrial facilities. To reduce energy consumption, steam system energy assessments have been conducted on a wide range of industry types over the course of five years through the Energy Savings Assessment (ESA) program administered by the U.S. Department of Energy (U.S. DOE). ESA energy assessments result in energy efficiency measure recommendations that are given potential energy and energy cost savings and potential implementation cost values. Saving and cost metrics that measure the impact recommended measures will have at facilities, described as percentages of facility baseline energy and energy cost, are developed from ESA data and used in analyses. Developed savings and cost metrics are examined along with implementation and rejection rates of recommended steam system energy efficiency measures. Based on analyses, implementation of steam system energy efficiency measures is driven primarily by cost metrics: payback period and measure implementation cost as a percentage of facility baseline energy cost (implementation cost percentage). Stated reasons for rejecting recommended measures are primarily based upon economic concerns. Additionally, implementation rates of measures are not only functions of savings and cost metrics, but time as well.

83

Energy Efficiency of Distributed Environmental Control Systems  

SciTech Connect

In this report, we present an analytical evaluation of the potential of occupant-regulated distributed environmental control systems (DECS) to enhance individual occupant thermal comfort in an office building with no increase, and possibly even a decrease in annual energy consumption. To this end we developed and applied several analytical models that allowed us to optimize comfort and energy consumption in partitioned office buildings equipped with either conventional central HVAC systems or occupant-regulated DECS. Our approach involved the following interrelated components: 1. Development of a simplified lumped-parameter thermal circuit model to compute the annual energy consumption. This was necessitated by the need to perform tens of thousands of optimization calculations involving different US climatic regions, and different occupant thermal preferences of a population of ~50 office occupants. Yearly transient simulations using TRNSYS, a time-dependent building energy modeling program, were run to determine the robustness of the simplified approach against time-dependent simulations. The simplified model predicts yearly energy consumption within approximately 0.6% of an equivalent transient simulation. Simulations of building energy usage were run for a wide variety of climatic regions and control scenarios, including traditional “one-size-fits-all” (OSFA) control; providing a uniform temperature to the entire building, and occupant-selected “have-it-your-way” (HIYW) control with a thermostat at each workstation. The thermal model shows that, un-optimized, DECS would lead to an increase in building energy consumption between 3-16% compared to the conventional approach depending on the climate regional and personal preferences of building occupants. Variations in building shape had little impact in the relative energy usage. 2. Development of a gradient-based optimization method to minimize energy consumption of DECS while keeping each occupant’s thermal dissatisfaction below a given threshold. The DECS energy usage was calculated using the simplified thermal model. OSFA control; providing a uniform temperature to the entire building, and occupant-selected HIYW control with a thermostat at each workstation were implemented for 3 cities representing 3 different climatic regions and control scenarios. It is shown that optimization allows DECS to deliver a higher level of individual and population thermal comfort while achieving annual energy savings between 14 and 26% compared to OSFA. The optimization model also allowed us to study the influence of the partitions’ thermal resistance and the variability of internal loads at each office. These influences didn’t make significant changes in the optimized energy consumption relative to OSFA. The results show that it is possible to provide thermal comfort for each occupant while saving energy compared to OSFA Furthermore, to simplify the implementation of this approach, a fuzzy logic system has been developed to generalize the overall optimization strategy. Its performance was almost as good as the gradient system. The fuzzy system provided thermal comfort to each occupant and saved energy compared to OSFA. The energy savings of the fuzzy system were not as high as for the gradient-optimized system, but the fuzzy system avoided complete connectivity, and the optimization did not have to be repeated for each population. 3. We employed a detailed CFD model of adjacent occupied cubicles to extend the thermal-circuit model in three significant ways: (a) relax the “office wall” requirement by allowing energy to flow between zones via advection as well as conduction, (b) improve the comfort model to account both for radiation as well as convection heat transfer, and (c) support ventilation systems in which the temperature is stratified, such as in underfloor air distribution systems. Initially, three-dimensional CFD simulations of several cubicle configurations, with an adjoining corridor, were performed both to understand the advection between cubicles and the

Khalifa, H. Ezzat; Isik, Can; Dannenhoffer, John F. III

2011-02-23T23:59:59.000Z

84

HVAC & Building Management Control System Energy Efficiency Replacements  

SciTech Connect

The project objective was the replacement of an aging, un-repairable HVAC system which has grown inefficient and a huge energy consumer with low energy and efficient HVAC units, and installation of energy efficient building control technologies at City's YMCA Community Center.

Hernandez, Adriana

2012-09-21T23:59:59.000Z

85

Energy-efficient deadline scheduling for heterogeneous systems  

Science Conference Proceedings (OSTI)

Energy efficiency is a major concern in modern high performance computing (HPC) systems and a power-aware scheduling approach is a promising way to achieve that. While there are a number of studies in power-aware scheduling by means of dynamic power ... Keywords: Deadline scheduling, Energy efficiency, High performance computing, Pricing scheme

Yan Ma; Bin Gong; Ryo Sugihara; Rajesh Gupta

2012-12-01T23:59:59.000Z

86

INTEGRATED ENERGY EFFICIENT WINDOW-WALL SYSTEMS  

SciTech Connect

The building industry faces the challenge of reducing energy use while simultaneously improving construction methods and marketability. This paper describes the first phase of a project to address these concerns by designing an Integrated Window Wall System (IWWS) that can be commercialized. This work builds on previous research conducted during the 1990's by Lawrence Berkeley national Laboratories (LBNL). During this phase, the objective was to identify appropriate technologies, problems and issues and develop a number of design concepts. Four design concepts were developed into prototypes and preliminary energy analyses were conducted Three of these concepts (the foam wall, steel wall, and stiffened plate designs) showed particular potential for meeting the project objectives and will be continued into a second phase where one or two of the systems will be brought closer to commercialization.

Michael Arney, Ph.D.

2002-12-31T23:59:59.000Z

87

High efficiency stoichiometric internal combustion engine system  

DOE Patents (OSTI)

A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

Winsor, Richard Edward (Waterloo, IA); Chase, Scott Allen (Cedar Falls, IA)

2009-06-02T23:59:59.000Z

88

Metering Air Compressor Systems for Efficiency: A Progress Report  

E-Print Network (OSTI)

Air compressors have energy efficiency quantified as SCFM/BHP. However, this efficiency fluctuates over a broad range based on the loading of the compressor. When multiple compressors operate with varying loads, as in a central plant, the overall system efficiency is totally unknown. With funding from California Energy Commission under the PIER Program, we spent considerable effort over the past few years to develop system efficiency for air compressor central plants. The system efficiency was termed CASE Index, which varies from 0 to about 320, and has the units of SCF/KWH. The procedure we developed, involved metering of input (KWH) and output (SCFM), in and out of the central plant. After the initial beta testing of the procedure, as more and more compressor professionals started to use the procedure and as more metering equipments entered the picture, some metering complications were encountered. These problems were dealt with and the procedure developed under this project can produce reliable data. This paper also presents the system efficiencies we have recorded so far and the opportunities they indicate. The data shows a wide range, from a low 82 to about 250 on a 0 to 320 scale. This confirms our expectations of large energy efficiency improvement potential in compressed air systems.

Joseph, B.

2005-01-01T23:59:59.000Z

89

Precipitation Efficiency of Warm-Season Midwestern Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

The precipitation efficiencies for mesoscale convective systems (MCS) over the central United States are calculated. During July–September 2000 and June–September 2001, 24 MCS for which sufficient data were available occurred over or near ...

Patrick Market; Stacy Allen; Roderick Scofield; Robert Kuligowski; Arnold Gruber

2003-12-01T23:59:59.000Z

90

Motor System Energy Efficiency Supply Curves: A Methodology for Assessing  

NLE Websites -- All DOE Office Websites (Extended Search)

Motor System Energy Efficiency Supply Curves: A Methodology for Assessing Motor System Energy Efficiency Supply Curves: A Methodology for Assessing the Energy Efficiency Potential of Industrial Motor Systems Speaker(s): Ali Hasanbeigi Date: February 8, 2011 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Aimee McKane Motor-driven equipment accounts for approximately 60% of manufacturing final electricity use worldwide. A major barrier to effective policymaking, and to more global acceptance of the energy efficiency potential in industrial motor systems, is the lack of a transparent methodology for quantifying the magnitude and cost-effectiveness of these energy savings. This paper presents the results of groundbreaking analyses conducted for five countries and one region to begin to address this barrier. Using a combination of expert opinion and available data from the United States,

91

Design and global optimization of high-efficiency thermophotovoltaic systems  

E-Print Network (OSTI)

Despite their great promise, small experimental thermophotovoltaic (TPV) systems at 1000 K generally exhibit extremely low power conversion efficiencies (approximately 1%), due to heat losses such as thermal emission of ...

Bermel, Peter A.

92

Mesoscale to Submesoscale Transition in the California Current System. Part III: Energy Balance and Flux  

Science Conference Proceedings (OSTI)

This is the last of a suite of three papers about the transition that occurs in numerical simulations for an idealized equilibrium, subtropical, eastern-boundary upwelling current system similar to the California Current. The transition is mainly ...

X. Capet; J. C. McWilliams; M. J. Molemaker; A. F. Shchepetkin

2008-10-01T23:59:59.000Z

93

Energy efficiency in wireless communication systems  

SciTech Connect

Wireless communication systems and methods utilize one or more remote terminals, one or more base terminals, and a communication channel between the remote terminal(s) and base terminal(s). The remote terminal applies a direct sequence spreading code to a data signal at a spreading factor to provide a direct sequence spread spectrum (DSSS) signal. The DSSS signal is transmitted over the communication channel to the base terminal which can be configured to despread the received DSSS signal by a spreading factor matching the spreading factor utilized to spread the data signal. The remote terminal and base terminal can dynamically vary the matching spreading factors to adjust the data rate based on an estimation of operating quality over time between the remote terminal and base terminal such that the amount of data being transmitted is substantially maximized while providing a specified quality of service.

Caffrey, Michael Paul; Palmer, Joseph McRae

2012-12-11T23:59:59.000Z

94

Efficient Power Profiling for Battery-Driven Embedded System Design  

E-Print Network (OSTI)

The ability to efficiently and accurately estimate battery life under different design choices at the system level is an important aid in designing battery-efficient systems. Recently developed battery models help by estimating battery life under given profiles of the battery discharge current over time. However, existing techniques for energy (or average power) estimation do not provide sufficient information (such as time profiles of system power consumption) to drive battery-life estimation. Techniques that are capable of generating such profiles often lack the efficiency required to support exploration at the system level. In this paper, we describe techniques for efficient generation of system-level power profiles, for use in a battery-life estimation framework. Our power profiling technique allows a designer to experiment with: 1) the mapping of system tasks to a set of architectural components and 2) the mapping of system communications to a specified communication architecture, and efficiently generate system power profiles for each alternative. The resulting profiles can then be analyzed using existing battery models to estimate battery lifetime and capacity. Extensive experiments conducted on an IEEE 802.11 MAC processor design demonstrate that our power profiler offers orders of magnitude improvement in runtimes over state-of-the-art cosimulation-based power estimation techniques, while suffering minimal loss of accuracy (average profiling error was 3.8%).

Kanishka Lahiri; Anand Raghunathan; Senior Member; Sujit Dey

2004-01-01T23:59:59.000Z

95

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

E-Print Network (OSTI)

comparison of VAV and VRF air conditioning systems in anThe variable refrigerant flow (VRF) and ground source heatthe energy efficiency of VRF systems compared with GSHP

Hong, Tainzhen

2010-01-01T23:59:59.000Z

96

Electric motor systems in developing countries: Opportunities for efficiency improvement  

SciTech Connect

This report presents an overview of the current status and efficiency improvement potential of industrial motor systems in developing countries. Better management of electric motor systems is of particular relevance in developing countries, where improved efficiency can lead to increased productivity and slower growth in electricity demand. Motor systems currently consume some 65--80% of the industrial electricity in developing countries. Drawing on studies from Thailand, India, Brazil, China, Pakistan, and Costa Rica, we describe potential efficiency gains in various parts of the motor system, from the electricity delivery system through the motor to the point where useful work is performed. We report evidence of a significant electricity conservation potential. Most of the efficiency improvement methods we examine are very cost-effective from a societal viewpoint, but are generally not implemented due to various barriers that deter their adoption. Drawing on experiences in North America, we discuss a range of policies to overcome these barriers, including education, training, minimum efficiency standards, motor efficiency testing protocols, technical assistance programs, and financial incentives.

Meyers, S.; Monahan, P.; Lewis, P.; Greenberg, S. [Lawrence Berkeley Lab., CA (United States); Nadel, S. [American Council for an Energy-Efficient Economy, Washington, DC (United States)

1993-08-01T23:59:59.000Z

97

Phase transitions in a mechanical system coupled to Glauber spins  

E-Print Network (OSTI)

A harmonic oscillator linearly coupled with a linear chain of Ising spins is investigated. The $N$ spins in the chain interact with their nearest neighbours with a coupling constant proportional to the oscillator position and to $N^{-1/2}$, are in contact with a thermal bath at temperature $T$, and evolve under Glauber dynamics. The oscillator position is a stochastic process due to the oscillator-spin interaction which produces drastic changes in the equilibrium behaviour and the dynamics of the oscillator. Firstly, there is a second order phase transition at a critical temperature $T_c$ whose order parameter is the oscillator stable rest position: this position is zero above $T_c$ and different from zero below $T_c$. This transition appears because the oscillator moves in an effective potential equal to the harmonic term plus the free energy of the spin system at fixed oscillator position. Secondly, assuming fast spin relaxation (compared to the oscillator natural period), the oscillator dynamical behaviour is described by an effective equation containing a nonlinear friction term that drives the oscillator towards the stable equilibrium state of the effective potential. The analytical results are compared with numerical simulation throughout the paper.

A. Prados; L. L. Bonilla; A. Carpio

2010-04-19T23:59:59.000Z

98

Multi Optical Transition Radiation System for ATF2  

SciTech Connect

In this paper we describe the design, installation and first calibration tests of a Multi Optical Transition Radiation System in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. This system will be a valuable tool for measuring beam sizes and emittances coming from the ATF Damping Ring. With an optical resolution of about 2 {micro}m an original OTR design (OTR1X) located after the septum at the entrance of the EXT line demonstrated the ability to measure a 5.5 {micro}m beam size in one beam pulse and to take many fast measurements. This gives the OTR the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter. Furthermore the nearby wire scanners will be a definitive test of the OTR as a beam emittance diagnostic device. The multi-OTR system design proposed here is based on the existing OTR1X.

Alabau-Gonzalvo, Javier; /Valencia U., IFIC; Blanch Gutierrez, Cesar; /Valencia U., IFIC; Civera, Jose Vicente; /Valencia U., IFIC; Faus-Golfe, Angeles; /Valencia U., IFIC; Garcia-Garrigos, Juan; /Valencia U., IFIC; Cruz, Juan; /SLAC; McCormick, Douglas; /SLAC; White, Glen; /SLAC

2012-07-13T23:59:59.000Z

99

CIBO's Energy Efficiency Handbook for Steam Power Systems  

E-Print Network (OSTI)

The Council of Industrial Boiler Owners (CIBO) has developed a handbook to help boiler operators get the best performance from their industrial steam systems. This energy efficiency handbook takes a comprehensive look at the boiler and steam system and addresses opportunities to improve performance every step of the way, including boiler maintenance, optimization, benchmarking, water treatment, and energy efficiency services. The handbook will include a checklist of items that operators should look for to improve their steam system's performance. This IETC paper will introduce the new CIBO handbook and describe its contents. The paper will also explain how the handbook is intended to be used.

Bessette, R. D.

1997-04-01T23:59:59.000Z

100

Efficient simulation of hybrid systems: A hybrid bond graph approach  

Science Conference Proceedings (OSTI)

Accurate and efficient simulations facilitate cost-effective design and analysis of large, complex, embedded systems, whose behaviors are typically hybrid, i.e. continuous behaviors interspersed with discrete mode changes. In this paper we present an ... Keywords: component-oriented modeling, dynamic causal assignment, hybrid bond graphs, modeling and simulation environments, simulation of hybrid systems

Indranil Roychoudhury; Matthew J Daigle; Gautam Biswas; Xenofon Koutsoukos

2011-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Results of a field test of heating system efficiency and thermal distribution system efficiency in a manufactured home  

SciTech Connect

A two-day test using electric coheating was performed on a manufactured home in Watertown, New York. The main objective of the test was to evaluate planned procedures for measuring thermal distribution system efficiency. (Thermal distribution systems are the ductwork or piping used to transport heat or cooling effect from the equipment that produces it to the building spaces in which it is used.) These procedures are under consideration for a standard method of test now being prepared by a special committee of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. The ability of a coheating test to give a credible and repeatable value for the overall heating system efficiency was supported by the test data. Distribution efficiency is derived from system efficiency by correcting for energy losses from the equipment. Alternative means for achieving this were tested and assessed. The best value for system efficiency in the Watertown house was 0.53, while the best value for distribution efficiency was 0.72.

Andrews, J.W.; Krajewski, R.F.; Strasser, J.J. [Brookhaven National Lab., Upton, NY (United States); Kinney, L.; Lewis, G. [Synertech Systems Corp., Syracuse, NY (United States)

1995-05-01T23:59:59.000Z

102

Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems  

SciTech Connect

This paper presents energy and life cycle climate performance (LCCP) analyses of a variety of supermarket refrigeration systems to identify designs that exhibit low environmental impact and high energy efficiency. EnergyPlus was used to model refrigeration systems in a variety of climate zones across the United States. The refrigeration systems that were modeled include the traditional multiplex DX system, cascade systems with secondary loops and the transcritical CO2 system. Furthermore, a variety of refrigerants were investigated, including R-32, R-134a, R-404A, R-1234yf, R-717, and R-744. LCCP analysis was used to determine the direct and indirect carbon dioxide emissions resulting from the operation of the various refrigeration systems over their lifetimes. Our analysis revealed that high-efficiency supermarket refrigeration systems may result in up to 44% less energy consumption and 78% reduced carbon dioxide emissions compared to the baseline multiplex DX system. This is an encouraging result for legislators, policy makers and supermarket owners to select low emission, high-efficiency commercial refrigeration system designs for future retrofit and new projects.

Fricke, Brian A [ORNL; Bansal, Pradeep [ORNL; Zha, Shitong [Hillphoenix

2013-01-01T23:59:59.000Z

103

A High Efficiency PSOFC/ATS-Gas Turbine Power System  

DOE Green Energy (OSTI)

A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.

W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

2001-02-01T23:59:59.000Z

104

Identifying Efficiency Degrading Faults in Split Air Conditioning Systems  

E-Print Network (OSTI)

Studies estimate that as much as 50% of packaged air conditioning systems operate in faulty conditions that degrade system efficiency. Common faults include: under- and over-charged systems (too much or too little refrigerant), faulty expansions valves (stuck valves, valve hunting, poorly tuned valve controllers), and fouled evaporators and condensers. Furthermore, air conditioning systems can often be adjusted to improve efficiency while continuing to meet cooling loads (adjusting system pressures, decreasing superheat setpoints). This study presents the design of a low cost device that can non-invasively measure system operating conditions, diagnose faults, estimate potential energy savings, and provide recommendations on how the system should be adjusted or repaired. Using eight external temperature measurements, the device potentially can detect and diagnose up to ten faults commonly found in HVAC systems. Steady state temperatures are compared to threshold values obtained from literature and HVAC manufacturers to detect and determine the severity of faults and subsequent reductions in coefficient of performance. Preliminary tests reveal the potential for the device to detect and diagnose common efficiency-degrading faults in HVAC systems.

Terrill, T. J.; Brown, M. L.; Cheyne, R. W. Jr.; Cousins, A. J.; Daniels, B. P.; Erb, K. L.; Garcia, P. A.; Leutermann, M. J.; Nel, A. J.; Robert, C. L.; Widger, S. B.; Williams, A. G.; Rasmussen, B. P.

2013-01-01T23:59:59.000Z

105

Energy Efficiency Evaluation of Guangzhou West Tower Façade System  

E-Print Network (OSTI)

Guangzhou West Tower is an extremely tall public building. The energy efficiency evaluation of its façade should be different than that of ordinary public buildings. Based on the national code GB50189-2005, “Design Standard for Energy efficiency of Public Buildings”, typical meteorological yearly data for Guangzhou were used and revised according to architectural character of Guangzhou West Tower. The energy efficiency design of a single skin façade and active airflow curtain wall was analyzed by a dynamic energy simulation tool and modified weather data. The payback period of initial investment in the façade system was evaluated based on simulation results. In addition, the results confirm the façade system scheme of Guangzhou West Tower.

Meng, Q.; Zhang, L.

2006-01-01T23:59:59.000Z

106

Boiler System Efficiency Improves with Effective Water Treatment  

E-Print Network (OSTI)

Water treatment is an important aspect of boiler operation which can affect efficiency or result in damage if neglected. Without effective water treatment, scale can form on boiler tubes, reducing heat transfer, and causing a loss of boiler efficiency and availability. Proper control of boiler blowdown is also important to assure clean boiler surfaces without wasting water, heat, and chemicals. Recovering hot condensate for reuse as boiler feedwater is another means of improving system efficiency. Condensate which is contaminated with corrosion products or process chemicals, however, is ill fit for reuse; and steam which leaks from piping, valves, traps and connections cannot be recovered. Effective chemical treatment, in conjunction with mechanical system improvements, can assure that condensate can be safely returned and valuable energy recovered.

Bloom, D.

1999-05-01T23:59:59.000Z

107

Toward green systems for cleanrooms: Energy efficient fan-filter units  

E-Print Network (OSTI)

Toward Green Systems for Cleanrooms: Energy Efficient Fan-FFU), energy efficiency, green system, electric power use,are challenges and benefits in green designs that integrate

Jeng, Ming-Shan; Xu, Tengfang; Lan, Chao-Ho

2004-01-01T23:59:59.000Z

108

Maximizing efficiency of solar-powered systems by load matching  

Science Conference Proceedings (OSTI)

Solar power is an important source of renewable energy for many low-power systems. Matching the power consumption level with the supply level can make a great difference in the efficiency of power utilization. This paper proposes a source-tracking power ... Keywords: load matching, photovoltaics, power management, power model, solar energy, solar-aware

Dexin Li; Pai H. Chou

2004-08-01T23:59:59.000Z

109

System Effects of High Efficiency Filters in Homes  

NLE Websites -- All DOE Office Websites (Extended Search)

System Effects of High Efficiency Filters in Homes System Effects of High Efficiency Filters in Homes Title System Effects of High Efficiency Filters in Homes Publication Type Conference Paper LBNL Report Number LBNL-6144E Year of Publication 2013 Authors Walker, Iain S., Darryl J. Dickerhoff, David Faulkner, and William J. N. Turner Conference Name ASHRAE Annual Conference Date Published 03/2013 Abstract Occupant concern about indoor air quality (IAQ) issues has led to the increased use of more effective air filters in residential heating and cooling systems. A drawback of improved filtration is that better filters tend to have more flow resistance. This can lead to lower system airflows that reduce heat exchanger efficiency, increase duct pressure that leads to increased air leakage for ducts and, in some case s, increased blower power consumption. There is currently little knowledge on the magnitude of these effects. In this study, the performance of ten central forced air systems was monitored for a year. The systems used either a Permanent Split Capacitor (PSC) or a Brushless Permanent Magnet (BPM) blower. Each system was operated with a range of filter efficiencies ranging from MERV 6 (the lowest currently permitted in ASHRAE Standard 62.2) up to MERV 16. Measurements were recorded every ten seconds for blower power, filter pressure drop, supply and return plenum pressures together with plenum and indoor temperatures. These detailed continuous measurements allowed observation of filter loading effects as well as the initial change in system performance when filters were swapped. The results of the field measurements were used in simulations to examine more general system performance effects for a wider range of climates. The field tests showed that system static pressures were highly influenced by filter selection, filter loading rates varied more from house to house than by MERV rating and overall were quite low in many of the homes. PSC motors showed reduced power and airflow as the filters loaded, but BPM motors attempted to maintain a constant airflow and increased their power to do so. The combined field test and simulation results from this study indicate that for MERV 10-13 filters the effects on energy use are small (5%) and usability. In systems using low MERV filters that are already close to blower performance limits the addition of a MERV 16 filter pushed the blowers to their performance limits.

110

Rail Transit Investments, Real Estate Values, and Land Use Change: A Comparative Analysis of Five California Rail Transit Systems  

E-Print Network (OSTI)

Paswell, Robert E. 1983. "Rail Transit Investment and CBDCervero, Robert. 1993. "Rail Transit and Jsmt Development.Assessing the hpacts of Urban Rail Transit: on Local Real

Landis, John; Guhathakurta, Subhrajit; Huang, William; Zhang, Ming

1995-01-01T23:59:59.000Z

111

High-efficiency multidetector system for tumor scanning  

SciTech Connect

A high-efficiency detector system developed especially for medical imaging has three specially cut Ge(Li) coaxial detectors (total volume 249 cm$sup 3$). At 122 keV, the peak efficiency is 93 percent of that of a 7.6 x 7.6 cm NaI (Tl) detector. Degradation of the paralleled energy resolution is avoided and resolution is improved by 35 percent over that of conventional output-summing techniques by gating the detector outputs. In effect this multiplexes them to a single line output. (auth)

Kirby, J.A.; Phelps, P.L.; Armantrout, G.A.; Sawyer, D.; Beck, R.N.

1975-11-18T23:59:59.000Z

112

Steam Power Partnership: Improving Steam System Efficiency Through Marketplace Partnerships  

E-Print Network (OSTI)

The Alliance to Save Energy, a national nonprofit organization based in Washington DC, and the U.S. Department of Energy are working with energy efficiency suppliers to promote the comprehensive upgrade of industrial steam systems. Like EPA's Green Lights and DOE's Motor Challenge, the Steam Power Partnership program will encourage industrial energy consumers to retrofit their steam plants wherever profitable. The Alliance has organized a "Steam Team" of trade associations, consulting engineering firms, and energy efficiency companies to help develop this public- private initiative.

Jones, T.

1997-04-01T23:59:59.000Z

113

Motor Systems Efficiency Supply Curves | Open Energy Information  

Open Energy Info (EERE)

Motor Systems Efficiency Supply Curves Motor Systems Efficiency Supply Curves Jump to: navigation, search Tool Summary Name: Motor Systems Efficiency Supply Curves Agency/Company /Organization: United Nations Industrial Development Organization Sector: Energy Focus Area: Energy Efficiency, Industry Topics: Technology characterizations Resource Type: Publications, Case studies/examples Website: www.unido.org/fileadmin/user_media/Services/Energy_and_Climate_Change/ Country: United States, Canada, Thailand, Vietnam, Brazil UN Region: South-Eastern Asia, "Latin America and Caribbean" is not in the list of possible values (Eastern Africa, Middle Africa, Northern Africa, Southern Africa, Western Africa, Caribbean, Central America, South America, Northern America, Central Asia, Eastern Asia, Southern Asia, South-Eastern Asia, Western Asia, Eastern Europe, Northern Europe, Southern Europe, Western Europe, Australia and New Zealand, Melanesia, Micronesia, Polynesia, Latin America and the Caribbean) for this property., Northern America, "Western & Eastern Europe" is not in the list of possible values (Eastern Africa, Middle Africa, Northern Africa, Southern Africa, Western Africa, Caribbean, Central America, South America, Northern America, Central Asia, Eastern Asia, Southern Asia, South-Eastern Asia, Western Asia, Eastern Europe, Northern Europe, Southern Europe, Western Europe, Australia and New Zealand, Melanesia, Micronesia, Polynesia, Latin America and the Caribbean) for this property.

114

Increase energy efficiency in systems and buildings and improve indoor  

NLE Websites -- All DOE Office Websites (Extended Search)

Increase energy efficiency in systems and buildings and improve indoor Increase energy efficiency in systems and buildings and improve indoor environment: How to validate comfort and energy reduction Speaker(s): Wouter Borsboom Date: December 8, 2009 - 12:00pm Location: 90-3122 TNO is a research institute which is active in the energy saving and indoor environment. We like to present our research, our goals and discuss the challenges and the opportunities for cooperation. Therefore we like to give a presentation about the following topic and we are also interested in a presentation of LBL and UC Berkeley. An important topic in the building industry is near zero energy buildings. Most countries in Europe implemented programs to advance this goal in one way or another. In near-zero energy buildings, the interaction between building and systems

115

Alternative Fuels Data Center: Mass Transit  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Mass Transit to Mass Transit to someone by E-mail Share Alternative Fuels Data Center: Mass Transit on Facebook Tweet about Alternative Fuels Data Center: Mass Transit on Twitter Bookmark Alternative Fuels Data Center: Mass Transit on Google Bookmark Alternative Fuels Data Center: Mass Transit on Delicious Rank Alternative Fuels Data Center: Mass Transit on Digg Find More places to share Alternative Fuels Data Center: Mass Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework Mass Transit Passenger-Miles per Gallon Passenger-miles per gallon (pmpg) is a metric for comparing mass transit and rideshare with typical passenger vehicle travel. Transportation system

116

Contactless prepaid and bankcards in transit fare collection systems  

E-Print Network (OSTI)

Many public transit agencies are considering direct acceptance of contactless credit and debit cards (collectively contactless bankcards) at gates in rail stations and on board buses. Concerns have been raised about riders ...

Brakewood, Candace Elizabeth

2010-01-01T23:59:59.000Z

117

An Efficient Vein Pattern-based Recognition System  

E-Print Network (OSTI)

This paper presents an efficient human recognition system based on vein pattern from the palma dorsa. A new absorption based technique has been proposed to collect good quality images with the help of a low cost camera and light source. The system automatically detects the region of interest from the image and does the necessary preprocessing to extract features. A Euclidean Distance based matching technique has been used for making the decision. It has been tested on a data set of 1750 image samples collected from 341 individuals. The accuracy of the verification system is found to be 99.26% with false rejection rate (FRR) of 0.03%.

Soni, Mohit; Rao, M S; Gupta, Phalguni

2010-01-01T23:59:59.000Z

118

Energy-Efficient Building HVAC Control Using Hybrid System LBMPC  

E-Print Network (OSTI)

Improving the energy-efficiency of heating, ventilation, and air-conditioning (HVAC) systems has the potential to realize large economic and societal benefits. This paper concerns the system identification of a hybrid system model of a building-wide HVAC system and its subsequent control using a hybrid system formulation of learning-based model predictive control (LBMPC). Here, the learning refers to model updates to the hybrid system model that incorporate the heating effects due to occupancy, solar effects, outside air temperature (OAT), and equipment, in addition to integrator dynamics inherently present in low-level control. Though we make significant modeling simplifications, our corresponding controller that uses this model is able to experimentally achieve a large reduction in energy usage without any degradations in occupant comfort. It is in this way that we justify the modeling simplifications that we have made. We conclude by presenting results from experiments on our building HVAC testbed, which s...

Aswani, Anil; Taneja, Jay; Krioukov, Andrew; Culler, David; Tomlin, Claire

2012-01-01T23:59:59.000Z

119

Electrical Equipment Replacement: Energy Efficiency versus System Compatibility  

E-Print Network (OSTI)

Electrical equipment components are replaced every day because of failure, obsolescence, or upgrade. Because of technological gains, replacement components are typically more energy efficient than older equipment. Life cycle cost analyses encourage end users to select the most energy efficient equipment when replacing motors, motor drives, transformers, lamps, ballasts, etc., given costs associated with energy consumption when compared with installation. The selection of replacement parts that are compatible with existing system components and loads is critical. The purpose of this paper is to discuss fundamental electrical design principles often overlooked when replacing existing equipment with energy efficient models. NOTE: The views expressed in this paper are those of the author and do not necessarily reflect the views of the United States of America, the U. S. Department of Justice, or the Federal Bureau of Prisons.

Massey, G. W.

2005-01-01T23:59:59.000Z

120

Measure it, See it, Manage it: Using Real Time Data to Benchmark, Optimize, and Sustain System Energy Efficiency  

E-Print Network (OSTI)

Compressed Air System Energy Efficiency Study for Del Monteand Sustain System Energy Efficiency Thomas Taranto, Dataindustrial system energy efficiency - providing plant

Taranto, Thomas; McKane, Aimee; Amon, Ricardo; Maulhardt, Michael

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Financing; A Cost Effective Alternative When Upgrading Energy Efficient Systems  

E-Print Network (OSTI)

In the 1990's, many organizations are attempting to do more, faster, with less cost and improved quality. In many cases, this involves improving the efficiency of their systems. Increased competition is creating pressure to continuously improve in order to effectively compete in the marketplace. One obvious method of reducing costs and improving productivity is to upgrade old, antiquated equipment such as lighting to more modern energy efficient systems. Most projects provide a return on investment to the owner in several years, through energy and demand savings, Power Utility rebates, maintenance savings and increased productivity, however, the initial capital expense required is cost prohibitive. Budget constraints, a lengthy and complicated approval process and large up-front capital requirements are only a few "road blocks" to improvement. In order to make an equipment acquisition, every company must consider how they will pay for it! How do companies acquire the equipment they need to be more competitive? One cost effective solution -FINANCING! There are numerous benefits to both the end user customer (Lessee) and the installing contractor from utilizing financing to upgrade or retrofit to energy efficient systems. It is possible to provide design, material, installation, maintenance and soft costs as well as positive cash flow to the end user by structuring financing terms and payments around the energy savings. A wide array of programs and services are offered by many different financial organizations.

Ertle, J. M.

1994-04-01T23:59:59.000Z

122

Efficient Bulk Data Replication for the Earth System Grid  

SciTech Connect

The Earth System Grid (ESG) community faces the difficult challenge of managing the distribution of massive data sets to thousands of scientists around the world. To move data replicas efficiently, the ESG has developed a data transfer management tool called the Bulk Data Mover (BDM). We describe the performance results of the current system and plans towards extending the techniques developed so far for the up- coming project, in which the ESG will employ advanced networks to move multi-TB datasets with the ulti- mate goal of helping researchers understand climate change and its potential impacts on world ecology and society.

Sim, Alex; Gunter, Dan; Natarajan, Vijaya; Shoshani, Arie; Williams, Dean; Long, Jeff; Hick, Jason; Lee, Jason; Dart, Eli

2010-03-10T23:59:59.000Z

123

Pumping systems efficiency improvements flow straight to thebottom line  

SciTech Connect

Industrial electrical motors account for two-thirds of theUS industrial electricity usage. Pumping systems account for an estimated25 percent of this electrical motor consumption, while pumping systems inuse in US chemical facilities consume over 37,000 GWh/year, based on USDepartment of Energy (DOE) data. A study funded by DOE estimatespotential energy savings within the chemical industry alone ofapproximately 20 percent, representing an energy savings of over 7,500GWh/year, through industrial pumping systems optimization using existing,proven techniques and technologies. This energy savings potentialrepresents significant cost savings potential for industrial facilities.Additionally, it has been shown that energy efficiency improvements toindustrial systems usually provide improved reliability, improvedproductivity, and reduced environmental costs.

Tutterow, Vestal; Casada, Don; McKane, Aimee

2002-07-08T23:59:59.000Z

124

Fuel Cell/Turbine Ultra High Efficiency Power System  

DOE Green Energy (OSTI)

FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will be utilized in the design of a 40-MW high efficiency Vision 21 power plant. Additionally, these tests are providing the valuable insight for DFC/Turbine power plant potential for load following, increased reliability, and enhanced operability.

Hossein, Ghezel-Ayagh

2001-11-06T23:59:59.000Z

125

Optimizing the use of public transit system during no-notice evacuation of urban areas  

Science Conference Proceedings (OSTI)

This paper proposes a methodology that can be used to design plans for evacuating transit-dependent citizens during no-notice disasters. A mixed-integer linear program is proposed to model the problem of finding optimal evacuation routes. The objective ... Keywords: Emergency evacuation, Mixed-integer linear programming, No-notice disasters, Public transit system

Fatemeh Sayyady; Sandra D. Eksioglu

2010-11-01T23:59:59.000Z

126

Operator awareness of system status during Fast Flux Test Facility transition to standby  

Science Conference Proceedings (OSTI)

A facility in transition, due to a change in its mission or its operating status, begins to depart from a previously well-defined normal mode of operation. The equipment becomes reconfigured or deactivated. In an environment of transition, the Fast Flux Test Facility (FFTF) has employed methods to enhance operator awareness of system status. These methods are described in this report.

Gibson, J.L.

1994-04-01T23:59:59.000Z

127

Lessons learned on closed cavity thermophotovoltaic system efficiency measurements  

DOE Green Energy (OSTI)

Previous efficiency measurements have highlighted that to accurately measure and predict thermophotovoltaic (TPV) integrated cell or array efficiencies, a thorough understanding of the system is required. This includes knowledge of intrinsic diode and filter characteristics, radiative surface properties of all materials used within the cavity, and an intimate knowledge of the radiator/photon source. As a result of these and other lessons learned, the cavity test fixture used in earlier experiments was redesigned. To reduce radiator temperature gradients, the radiator was oversized and thickened, cavity walls were eliminated, the diode heat sink and shielding material were separated, and the cold side was redesigned to incorporate a steady state heat absorbed measurement technique. This redesigned test fixture provides an isothermal radiator and significantly enhances calorimetry capabilities. This newly designed cavity test fixture, in conjunction with the Monte Carlo Photon Transport code RACER-X, was used to improve and demonstrate the understanding of in-cavity TPV diode/module system efficiency testing. A single TPV diode was tested in this new fixture and yielded good agreement between measurements and predictions.

Gethers, C.K.; Ballinger, C.T.; DePoy, D.M. [Lockheed Martin Corp., Schenectady, NY (United States)

1998-10-01T23:59:59.000Z

128

Alternative Fuels Data Center: Active Transit  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Active Transit to Active Transit to someone by E-mail Share Alternative Fuels Data Center: Active Transit on Facebook Tweet about Alternative Fuels Data Center: Active Transit on Twitter Bookmark Alternative Fuels Data Center: Active Transit on Google Bookmark Alternative Fuels Data Center: Active Transit on Delicious Rank Alternative Fuels Data Center: Active Transit on Digg Find More places to share Alternative Fuels Data Center: Active Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework Active Transit Photo of people riding bikes. Active transit is human-powered transportation such as biking and walking. Active transportation eliminates vehicle miles traveled altogether, so this

129

System and method to determine electric motor efficiency nonintrusively  

Science Conference Proceedings (OSTI)

A system and method for nonintrusively determining electric motor efficiency includes a processor programed to, while the motor is in operation, determine a plurality of stator input currents, electrical input data, a rotor speed, a value of stator resistance, and an efficiency of the motor based on the determined rotor speed, the value of stator resistance, the plurality of stator input currents, and the electrical input data. The determination of the rotor speed is based on one of the input power and the plurality of stator input currents. The determination of the value of the stator resistance is based on at least one of a horsepower rating and a combination of the plurality of stator input currents and the electrical input data. The electrical input data includes at least one of an input power and a plurality of stator input voltages.

Lu, Bin (Kenosha, WI); Habetler, Thomas G. (Snellville, GA); Harley, Ronald G. (Lawrenceville, GA)

2011-08-30T23:59:59.000Z

130

Energy Efficient Steam Trapping of Trace Heating Systems  

E-Print Network (OSTI)

Since as many as 40-60% of a plant's steam traps may be used on steam tracer lines, it is essential to select the correct, properly sized 'traps'; to optimize the efficient removal of condensate while providing maximum heat transfer to maintain desired product temperatures and greatly reduce steam losses. Factors related to achieving uniform product temperatures and maximum heat transfer rates and energy efficiency are: 1.Types and Methods used for Steam Tracing; 2. Systematic heat balance required to achieve economic tracer lengths; 3. Maximum allowable trapping distance for specific applications 4.Data important to determine condensate loads; 5. Trap selection, sizing, good installation practices, and proper maintenance. Using an engineered approach to steam trapping of trace heating systems have resulted in stable tracer line temperatures while reducing steam consumption 10-50% with minimum maintenance.

Krueger, R. G.; Wilt, G. W.

1981-01-01T23:59:59.000Z

131

Integration of High Efficiency Solar Cells on Carriers for Concentrating System Applications .  

E-Print Network (OSTI)

??High efficiency multi-junction (MJ) solar cells were packaged onto receiver systems. The efficiency change of concentrator cells under continuous high intensity illumination was done. Also,… (more)

Chow, Simon Ka Ming

2011-01-01T23:59:59.000Z

132

Spin-Orbit Alignment of the TrES-4 Transiting Planetary System and Possible Additional Radial-Velocity Variation  

E-Print Network (OSTI)

We report new radial velocities of the TrES-4 transiting planetary system, including observations of

Narita, Norio

133

Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems  

Science Conference Proceedings (OSTI)

Industrial manufacturing in the U.S. accounts for roughly one third of the 98 quadrillion Btu total energy consumption. Motor system losses amount to 1.3 quadrillion Btu, which represents the largest proportional loss of any end-use category, while pumps alone represent over 574 trillion BTU (TBTU) of energy loss each year. The efficiency of machines with moving components is a function of the amount of energy lost to heat because of friction between contacting surfaces. The friction between these interfaces also contributes to downtime and the loss of productivity through component wear and subsequent repair. The production of new replacement parts requires additional energy. Among efforts to reduce energy losses, wear-resistant, low-friction coatings on rotating and sliding components offer a promising approach that is fully compatible with existing equipment and processes. In addition to lubrication, one of the most desirable solutions is to apply a protective coating or surface treatment to rotating or sliding components to reduce their friction coefficients, thereby leading to reduced wear. Historically, a number of materials such as diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and tungsten carbide (WC) have been examined as tribological coatings. The primary objective of this project was the development of a variety of thin film nanocoatings, derived from the AlMgB14 system, with a focus on reducing wear and friction in both industrial hydraulics and cutting tool applications. Proof-of-concept studies leading up to this project had shown that the constituent phases, AlMgB14 and TiB2, were capable of producing low-friction coatings by pulsed laser deposition. These coatings combine high hardness with a low friction coefficient, and were shown to substantially reduce wear in laboratory tribology tests. Selection of the two applications was based largely on the concept of improved mechanical interface efficiencies for energy conservation. In mobile hydraulic systems, efficiency gains through low friction would translate into improved fuel economy and fewer greenhouse gas emissions. Stationary hydraulic systems, accordingly, would consume less electrical power. Reduced tooling wear in machining operations would translate to greater operating yields, while lowering the energy consumed during processing. The AlMgB14 nanocoatings technology progressed beyond baseline laboratory tests into measurable energy savings and enhancements to product durability. Three key hydraulic markets were identified over the course of the project that will benefit from implementation: industrial vane pumps, orbiting valve-in-star hydraulic motors, and variable displacement piston pumps. In the vane pump application, the overall product efficiency was improved by as much as 11%. Similar results were observed with the hydraulic motors tested, where efficiency gains of over 10% were noted. For variable displacement piston pumps, overall efficiency was improved by 5%. For cutting tools, the most significant gains in productivity (and, accordingly, the efficiency of the machining process as a whole) were associated with the roughing and finishing of titanium components for aerospace systems. Use of the AlMgB14 nanocoating in customer field tests has shown that the coated tools were able to withstand machining rates as high as 500sfm (limited only by the substrate material), with relatively low flank wear when compared to other industrial offerings. AlMgB14 coated tools exhibited a 60% improvement over similarly applied TiAlN thin films. Furthermore, AlMgB14-based coatings in these particular tests lasted twice as long than their TiAlN counterparts at the 500sfm feed rates. Full implementation of the technology into the industrial hydraulic and cutting tool markets equates to a worldwide energy savings of 46 trillion BTU/year by 2030. U.S.-based GHG emissions associated with the markets identified would fall accordingly, dropping by as much as 50,000 tonnes annually.

Clifton B. Higdon III

2011-01-07T23:59:59.000Z

134

Developing Energy Efficient Roof Systems DEERS | Open Energy Information  

Open Energy Info (EERE)

Roof Systems DEERS Roof Systems DEERS Jump to: navigation, search Name Developing Energy Efficient Roof Systems (DEERS) Place Ripon, California Zip 95366 Sector Solar Product Developer of roof top solar PV projects. Coordinates 43.84582°, -88.837054° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.84582,"lon":-88.837054,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

135

Short-Term Test Results: Transitional Housing Energy Efficiency Retrofit in the Hot-Humid Climate  

SciTech Connect

This project evaluates the renovation of a 5,800 ft2, multi-use facility located in St. Petersburg, on the west coast of central Florida, in the hot humid climate. An optimal package of retrofit measures was designed to deliver 30-40% annual energy cost savings for this building with annual utility bills exceeding $16,000 and high base load consumption. Researchers projected energy cost savings for potential retrofit measures based on pre-retrofit findings and disaggregated, weather normalized utility bills as a basis for simulation true-up. A cost-benefit analysis was conducted for the seven retrofit measures implemented; adding attic insulation and sealing soffits, tinting windows, improving whole building air-tightness, upgrading heating and cooling systems and retrofitting the air distribution system, replacing water heating systems, retrofitting lighting, and replacing laundry equipment. The projected energy cost savings for the full retrofit package based on a post-retrofit audit is 35%. The building's architectural characteristics, vintage, and residential and commercial uses presented challenges for both economic projections and retrofit measure construction.

Sutherland, K.; Martin, E.

2013-02-01T23:59:59.000Z

136

Short-Term Test Results: Transitional Housing Energy Efficiency Retrofit in the Hot-Humid Climate  

SciTech Connect

This project evaluates the renovation of a 5,800 ft2, multi-use facility located in St. Petersburg, on the west coast of central Florida, in the hot humid climate. An optimal package of retrofit measures was designed to deliver 30-40% annual energy cost savings for this building with annual utility bills exceeding $16,000 and high base load consumption. Researchers projected energy cost savings for potential retrofit measures based on pre-retrofit findings and disaggregated, weather normalized utility bills as a basis for simulation true-up. A cost-benefit analysis was conducted for the seven retrofit measures implemented; adding attic insulation and sealing soffits, tinting windows, improving whole building air-tightness, upgrading heating and cooling systems and retrofitting the air distribution system, replacing water heating systems, retrofitting lighting, and replacing laundry equipment. The projected energy cost savings for the full retrofit package based on a post-retrofit audit is 35%. The building's architectural characteristics, vintage, and residential and commercial uses presented challenges for both economic projections and retrofit measure construction.

Sutherland, K.; Martin, E.

2013-02-01T23:59:59.000Z

137

Mesoscale to Submesoscale Transition in the California Current System. Part II: Frontal Processes  

Science Conference Proceedings (OSTI)

This is the second of three papers investigating the regime transition that occurs in numerical simulations for an idealized, equilibrium, subtropical, eastern boundary, upwelling current system similar to the California Current. The emergent ...

X. Capet; J. C. McWilliams; M. J. Molemaker; A. F. Shchepetkin

2008-01-01T23:59:59.000Z

138

Transitions from Hadley to Rossby Flows in Internally Forced Rotating Spherical Systems  

Science Conference Proceedings (OSTI)

The possibility of global-scale transitions between atmospheric Hadley and Rossby regimes is investigated with a highly idealized, nonlinear, vertically continuous, rotating, spherical system. Low-order spectral versions of the model are used ...

R. Wayne Higgins; Hampton N. Shirer

1990-05-01T23:59:59.000Z

139

Method and system for efficiently searching an encoded vector index  

DOE Patents (OSTI)

Method and system aspects for efficiently searching an encoded vector index are provided. The aspects include the translation of a search query into a candidate bitmap, and the mapping of data from the candidate bitmap into a search result bitmap according to entry values in the encoded vector index. Further, the translation includes the setting of a bit in the candidate bitmap for each entry in a symbol table that corresponds to candidate of the search query. Also included in the mapping is the identification of a bit value in the candidate bitmap pointed to by an entry in an encoded vector.

Bui, Thuan Quang (Alameda, CA); Egan, Randy Lynn (Rochester, MN); Kathmann, Kevin James (Rochester, MN)

2001-09-04T23:59:59.000Z

140

Measured Performance of Energy-Efficient Computer Systems  

E-Print Network (OSTI)

The intent of this study is to explore the potential performance of both Energy Star computers/printers and add-on control devices individually, and their expected savings if collectively applied in a typical office building in a hot and humid climate. Recent surveys have shown that the use of personal computer systems in commercial office buildings is expanding rapidly. The energy consumption of such a growing end-use also has a significant impact on the total building power demand. In warmer climates, office equipment energy use has important implications for building cooling loads as well as those directly associated with computing tasks. Recently, the Environmental Protection Agency (EPA) has developed an Energy Star (ES) rating system intended to endorse more efficient equipment. To research the comparative performance of conventional and low-energy computer systems, four Energy Star computer systems and two computer systems equipped with energy saving devices were monitored for power demand. Comparative data on the test results are summarized. In addition, a brief analysis uses the DOE-2.1E computer simulation to examine the impact of the test results and HVAC interactions if generically applied to computer systems in a modern office building in Florida's climate.

Floyd, D. B.; Parker, D. S.

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Rail Transit Investments, Real Estate Values, and Land Use Change: A Comparative Analysis of Five California Rail Transit Systems  

E-Print Network (OSTI)

findings of this research: Proximity to rail mass transit isunderlying this research is whether urban rail transitunderlying this research is whether urban rail transit

Landis, John; Guhathakurta, Subhrajit; Huang, William; Zhang, Ming; Fukuji, Bruce

1995-01-01T23:59:59.000Z

142

Process for preparing high-transition-temperature superconductors in the Nb-Al-Ge system  

DOE Patents (OSTI)

The patent describes a process for preparing superconducting materials in the Nb-Al-Ge system having transition temperatures in excess of 19K. The process comprises premixing powdered constituents, pressing them into a plug, heating the plug to 1,450-1,800C for 30 minutes to an hour under vacuum or an inert atmosphere, and annealing at moderate temperatures for reasonably long times (approximately 50 hours). High transition-temperature superconductors, including those in the Nb3(Al,Ge) system, prepared in accordance with this process exhibit little degradation in the superconducting transition temperature on being ground to -200 mesh powder. (GRA)

Giorgi, A.L.; Szklarz, E.G.

1973-01-30T23:59:59.000Z

143

Surrogater: A Simple Yet Efficient Document Condensation System  

E-Print Network (OSTI)

This paper describes Surrogater, a simple yet efficient document condensation system that is applicable for commercial use. The system consists of two components, a preprocessing component for automatic generation of key terms for a predefined topic, and a condensation component that produces the condensed versions of on-line documents. To evaluate its performance, we compared Surrogater with five other summarization technologies, including Searchable LEAD, a commercial product. Twenty topics across four domains were evaluated, totalling. 30 documents and 1800 summaries. A two-way ANOVA test suggested that Surrogater performed at least equally well, if not better, compared to other commercial or nearly commercial products. More significantly, the empirical comparison did not show any dramatic differences in performance between Surrogater and Searchable LEAD as reported in an earlier study (Brandow et al. 1995) 1.

Joe Zhou

1998-01-01T23:59:59.000Z

144

Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems  

DOE Green Energy (OSTI)

This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials.

Peter J. Blau

2000-04-26T23:59:59.000Z

145

Tandem filters using frequency selective surfaces for enhanced conversion efficiency in a thermophotovoltaic energy conversion system  

DOE Patents (OSTI)

This invention relates to the field of thermophotovoltaic (TPV) direct energy conversion. In particular, TPV systems use filters to minimize parasitic absorption of below bandgap energy. This invention constitutes a novel combination of front surface filters to increase TPV conversion efficiency by reflecting useless below bandgap energy while transmitting a very high percentage of the useful above bandgap energy. In particular, a frequency selective surface is used in combination with an interference filter. The frequency selective surface provides high transmission of above bandgap energy and high reflection of long wavelength below bandgap energy. The interference filter maintains high transmission of above bandgap energy and provides high reflection of short wavelength below bandgap energy and a sharp transition from high transmission to high reflection.

Dziendziel, Randolph J. (Middle Grove, NY); Baldasaro, Paul F. (Clifton Park, NY); DePoy, David M. (Clifton Park, NY)

2010-09-07T23:59:59.000Z

146

Tandem filters using frequency selective surfaces for enhanced conversion efficiency in a thermophotovoltaic energy conversion system  

DOE Patents (OSTI)

This invention relates to the field of thermophotovoltaic (TPV) direct energy conversion. In particular, TPV systems use filters to minimize parasitic absorption of below bandgap energy. This invention constitutes a novel combination of front surface filters to increase TPV conversion efficiency by reflecting useless below bandgap energy while transmitting a very high percentage of the useful above bandgap energy. In particular, a frequency selective surface is used in combination with an interference filter. The frequency selective surface provides high transmission of above bandgap energy and high reflection of long wavelength below bandgap energy. The interference filter maintains high transmission of above bandgap energy and provides high reflection of short wavelength below bandgap energy and a sharp transition from high transmission to high reflection.

Dziendziel, Randolph J. (Middle Grove, NY); DePoy, David Moore (Clifton Park, NY); Baldasaro, Paul Francis (Clifton Park, NY)

2007-01-23T23:59:59.000Z

147

Offshore loading-system design is aimed at higher efficiency  

SciTech Connect

Mobil Shipping and Transporation Co. has completed the design of an offshore loading system aimed at overcoming the limitations of existing terminals. The loading/mooring/storage system (LMS) is a semisubmersible vessel with ship mooring and loading facilities atop a box-shaped crude storage structure, which is well below the water line away from the effect of waves and clear of loading tankers' bows. The storage volume equals or exceeds that of a VLCC. There are 15 dual-purpose cargo/ballast tanks in the lower section with a control tower over the center tank. The loading system is designed to load 800,000 bbl of crude in about 12 hr. Each tank contains a diagonally suspended synthetic rubber diaphragm that will isolate crude from water ballast. Computer simulations based on North Sea weather data indicate that the LMS will allow marine loading efficiencies of at least 95Vertical Bar3< with total storage of a week's production or more. Other advantages of the LMS include the ability to moor shuttle tankers up to 200,000 dwt; self-contained repair and maintenance capabilities; and mobility. Variations of anchoring and riser systems for the LMS are discussed.

1978-05-08T23:59:59.000Z

148

Energy Efficiency Labeling System & its Development in China  

Energy.gov (U.S. Department of Energy (DOE))

Information about the regulations, formats, objectives, and implementation of energy efficiency labeling in China.

149

Energy Transitions/Marcellus White Paper September 22, 2010 version A Systems Research Approach to Regional Energy  

E-Print Network (OSTI)

Energy Transitions/Marcellus White Paper September 22, 2010 version Page 1 A Systems Research Approach to Regional Energy Transitions: The Case of Marcellus Shale Gas Development White Paper A Report/Marcellus White Paper September 22, 2010 version Page 2 A Systems Research Approach to Regional Energy Transitions

Wang, Z. Jane

150

SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Efficiency Thermal Energy High-Efficiency Thermal Energy Storage System for CSP to someone by E-mail Share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Facebook Tweet about SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Twitter Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Google Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Delicious Rank SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Digg Find More places to share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act

151

SunShot Initiative: High-Efficiency Thermal Storage System for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Efficiency Thermal Storage System for Solar Plants to someone by E-mail Share SunShot Initiative: High-Efficiency Thermal Storage System for Solar Plants on Facebook Tweet about...

152

Monitoring System Used to Optimize Compressed Air System Efficiency, Cut Costs  

E-Print Network (OSTI)

In 1994, Thomson Consumer Electronics (RCA), an international manufacturer of electronics equipment purchased a UtillTRACK® Monitoring System for a plant in Indianapolis, Indiana. The system monitored gas and electric meters, substations, main feeders, and major equipment and systems including compressed air. For the compressed air system, monitored data included compressor amps, electrical demand and consumption, pressure and airflow. The resulting UtiliTRACK® reports and graphs showed a significant variation in system efficiency depending upon the demand for air (day of week, time of day, production schedule) and which compressor or compressors were operating. By working with the boiler plant operators and making minor modifications to the existing compressor controls, the operating sequence was modified to maintain high system efficiency under all operating conditions. Monitored data after the changes were made showed a 20% reduction in compressed air system operating costs.

Holmes, W. A.

1998-04-01T23:59:59.000Z

153

COOLING FAN AND SYSTEM PERFORMANCE AND EFFICIENCY IMPROVEMENTS  

Science Conference Proceedings (OSTI)

Upcoming emissions regulations (Tiers 3, 4a and 4b) are imposing significantly higher heat loads on the cooling system than lesser regulated machines. This work was a suite of tasks aimed at reducing the parasitic losses of the cooling system, or improving the design process through six distinct tasks: 1. Develop an axial fan that will provide more airflow, with less input power and less noise. The initial plan was to use Genetic Algorithms to do an automated fan design, incorporating forward sweep for low noise. First and second generation concepts could not meet either performance or sound goals. An experienced turbomachinery designer, using a specialized CFD analysis program has taken over the design and has been able to demonstrate a 5% flow improvement (vs 10% goal) and 10% efficiency improvement (vs 10% goal) using blade twist only. 2. Fan shroud developments, using an 'aeroshroud' concept developed at Michigan State University. Performance testing at Michigan State University showed the design is capable of meeting the goal of a 10% increase in flow, but over a very narrow operating range of fan performance. The goal of 10% increase in fan efficiency was not met. Fan noise was reduced from 0 to 2dB, vs. a goal of 5dB at constant airflow. The narrow range of fan operating conditions affected by the aeroshroud makes this concept unattractive for further development at this time 3. Improved axial fan system modeling is needed to accommodate the numbers of cooling systems to be redesigned to meet lower emissions requirements. A CFD fan system modeling guide has been completed and transferred to design engineers. Current, uncontrolled modeling practices produce flow estimates in some cases within 5% of measured values, and in some cases within 25% of measured values. The techniques in the modeling guide reduced variability to the goal of + 5% for the case under study. 4. Demonstrate the performance and design versatility of a high performance fan. A 'swept blade mixed flow' fan was rapid prototyped from cast aluminum for a performance demonstration on a small construction machine. The fan was mounted directly in place of the conventional fan (relatively close to the engine). The goal was to provide equal airflow at constant fan speed, with 75% of the input power and 5 dB quieter than the conventional fan. The result was a significant loss in flow with the prototype due to its sensitivity to downstream blockage. This sensitivity to downstream blockage affects flow, efficiency, and noise all negatively, and further development was terminated. 5. Develop a high efficiency variable speed fan drive to replace existing slipping clutch style fan drives. The goal for this task was to provide a continuously variable speed fan drive with an efficiency of 95%+ at max speed, and losses no greater than at max speed as the fan speed would vary throughout its entire speed range. The process developed to quantify the fuel savings potential of a variable speed fan drive has produced a simple tool to predict the fuel savings of a variable speed drive, and has sparked significant interest in the use of variable speed fan drive for Tier 3 emissions compliant machines. The proposed dual ratio slipping clutch variable speed fan drive can provide a more efficient system than a conventional single ratio slipping clutch fan drive, but could not meet the established performance goals of this task, so this task was halted in a gate review prior to the start of detailed design. 6. Develop a cooling system air filtration device to allow the use of automotive style high performance heat exchangers currently in off road machines. The goal of this task was to provide a radiator air filtration system that could allow high fin density, louvered radiators to operate in a find dust application with the same resistance to fouling as a current production off-road radiator design. Initial sensitivity testing demonstrated that fan speed has a significant impact on the fouling of radiator cores due to fine dusts, so machines equipped with continuously variabl

Ronald Dupree

2005-07-31T23:59:59.000Z

154

Transit Timing Observations from Kepler: III. Confirmation of 4 Multiple Planet Systems by a Fourier-Domain Study of Anti-correlated Transit Timing Variations  

SciTech Connect

We present a method to confirm the planetary nature of objects in systems with multiple transiting exoplanet candidates. This method involves a Fourier-domain analysis of the deviations in the transit times from a constant period that result from dynamical interactions within the system. The combination of observed anticorrelations in the transit times and mass constraints from dynamical stability allow us to claim the discovery of four planetary systems, Kepler-25, Kepler-26, Kepler-27 and Kepler-28, containing eight planets and one additional planet candidate.

Steffen, Jason H.; /Fermilab; Fabrycky, Daniel C.; /Lick Observ.; Ford, Eric B.; /Florida U.; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Fressin, Francois; /Harvard-Smithsonian Ctr. Astrophys.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Lissauer, Jack J.; /NASA, Ames; Rowe, Jason F.; /SETI Inst., Mtn. View /NASA, Ames; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Welsh, William F.; /Caltech; Borucki, William J.; /NASA, Ames /UC, Santa Barbara

2012-01-01T23:59:59.000Z

155

IMPACTS OF REFRIGERANTLINE LENGTH ON SYSTEM EFFICIENCY IN RESIDENTIAL HEATING AND COOLING SYSTEMS USING REFRIGERANT DISTRIBUTION.  

Science Conference Proceedings (OSTI)

The effects on system efficiency of excess refrigerant line length are calculated for an idealized residential heating and cooling system. By excess line length is meant refrigerant tubing in excess of the 25 R provided for in standard equipment efficiency test methods. The purpose of the calculation is to provide input for a proposed method for evaluating refrigerant distribution system efficiency. A refrigerant distribution system uses refrigerant (instead of ducts or pipes) to carry heat and/or cooling effect from the equipment to the spaces in the building in which it is used. Such systems would include so-called mini-splits as well as more conventional split systems that for one reason or another have the indoor and outdoor coils separated by more than 25 ft. This report performs first-order calculations of the effects on system efficiency, in both the heating and cooling modes, of pressure drops within the refrigerant lines and of heat transfer between the refrigerant lines and the space surrounding them.

ANDREWS, J.W.

2001-04-01T23:59:59.000Z

156

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

sizing ? Cooling tower and condenser optimization ? Controland cooling tower or condenser fans. Figure 1 and Figure 2those with evaporative condensers are more efficient than

Xu, Tengfang

2005-01-01T23:59:59.000Z

157

Solid-solid collapse transition in a two dimensional model molecular system  

E-Print Network (OSTI)

Solid-solid collapse transition in open framework structures is ubiquitous in nature. The real difficulty in understanding detailed microscopic aspects of such transitions in molecular systems arises from the interplay between different energy and length scales involved in molecular systems, often mediated through a solvent. In this work we employ Monte Carlo (MC) simulations to study the collapse transition in a model molecular system interacting via both isotropic as well as anisotropic interactions having different length and energy scales. The model we use is known as Mercedes-Benz (MB) which for a specific set of parameters sustains three solid phases: honeycomb, oblique and triangular. In order to study the temperature induced collapse transition, we start with a metastable honeycomb solid and induce transition by heating. High density oblique solid so formed has two characteristic length scales corresponding to isotropic and anisotropic parts of interaction potential. Contrary to the common believe and classical nucleation theory, interestingly, we find linear strip-like nucleating clusters having significantly different order and average coordination number than the bulk stable phase. In the early stage of growth, the cluster grows as linear strip followed by branched and ring-like strips. The geometry of growing cluster is a consequence of the delicate balance between two types of interactions which enables the dominance of stabilizing energy over the destabilizing surface energy. The nuclei of stable oblique phase are wetted by intermediate order particles which minimizes the surface free energy. We observe different pathways for pressure and temperature induced transitions.

Rakesh S. Singh; Biman Bagchi

2013-04-11T23:59:59.000Z

158

Design and global optimization of high-efficiency solar thermal systems with tungsten cermets  

E-Print Network (OSTI)

Solar thermal, thermoelectric, and thermophotovoltaic (TPV) systems have high maximum theoretical efficiencies; experimental systems fall short because of losses by selective solar absorbers and TPV selective emitters. To ...

Chester, David A.

159

Building bus rapid transit into the existing public transit system : competition and integration of BRT and the Urban Rail Transit in cities in China  

E-Print Network (OSTI)

BRT is a new type of bus transit with high speed and capacity. With its advantages and benefits, BRT is getting popular in the world, including China. Since BRT and urban rail transit (URT) are both rapid public transports, ...

Zhan, Yun, M.C.P. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

160

Transition to cloud computing in healthcare information systems  

E-Print Network (OSTI)

This thesis is a study on the adoption of cloud computing in healthcare information technology industry. It provides a guideline for people who are trying to bring cloud computing into healthcare information systems through ...

Ren, Haiying, S.M. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Width bifurcation and dynamical phase transitions in open quantum systems  

E-Print Network (OSTI)

The states of an open quantum system are coupled via the environment of scattering wavefunctions. The complex coupling coefficients $\\omega$ between system and environment arise from the principal value integral and the residuum. At high level density where the resonance states overlap, the dynamics of the system is determined by exceptional points. At these points, the eigenvalues of two states are equal and the corresponding eigenfunctions are linearly dependent. It is shown in the present paper that Im$(\\omega)$ and Re$(\\omega)$ influence the system properties differently in the surrounding of exceptional points. Controlling the system by a parameter, the eigenvalues avoid crossing in energy near an exceptional point under the influence of Re$(\\omega)$ in a similar manner as it is well known from discrete states. Im$(\\omega)$ however leads to width bifurcation and finally (when the system is coupled to one channel, i.e. to a common continuum of scattering wavefunctions), to a splitting of the system into two parts with different characteristic time scales. Physically, the system is stabilized by this splitting since the lifetimes of most ($N-1$) states are longer than before while that of only one state is shorter. In the cross section the short-lived state appears as a background term in high-resolution experiments. The wavefunctions of the long-lived states are mixed in those of the original ones in a comparably large parameter range. Numerical results for the eigenvalues and eigenfunctions are shown for $N=2, ~4$ and 10 states coupled mostly to 1 channel.

Hichem Eleuch; Ingrid Rotter

2013-03-26T23:59:59.000Z

162

Theory of quantum metal to superconductor transitions in highly conducting systems  

SciTech Connect

We derive the theory of the quantum (zero temperature) superconductor to metal transition in disordered materials when the resistance of the normal metal near criticality is small compared to the quantum of resistivity. This can occur most readily in situations in which 'Anderson's theorem' does not apply. We explicitly study the transition in superconductor-metal composites, in an swave superconducting film in the presence of a magnetic field, and in a low temperature disordered d-wave superconductor. Near the point of the transition, the distribution of the superconducting order parameter is highly inhomogeneous. To describe this situation we employ a procedure which is similar to that introduced by Mott for description of the temperature dependence of the variable range hopping conduction. As the system approaches the point of the transition from the metal to the superconductor, the conductivity of the system diverges, and the Wiedemann-Franz law is violated. In the case of d-wave (or other exotic) superconductors we predict the existence of (at least) two sequential transitions as a function of increasing disorder: a d-wave to s-wave, and then an s-wave to metal transition.

Spivak, B.

2010-04-06T23:59:59.000Z

163

Energy Efficient Pump Control for an Offshore Oil Processing System Yang, Zhenyu; Soleiman, Kian ; Lhndorf, Bo  

E-Print Network (OSTI)

Energy Efficient Pump Control for an Offshore Oil Processing System Yang, Zhenyu; Soleiman, Kian. (2012). Energy Efficient Pump Control for an Offshore Oil Processing System: IFAC Workshop - Automatic of a pump system for an offshore oil processing system is investigated. The seawater is lifted up by a pump

Yang, Zhenyu

164

Using System Dynamics to Model the Transition to Biofuels in the United States: Preprint  

DOE Green Energy (OSTI)

Transitioning to a biofuels industry that is expected to displace about 30% of current U.S. gasoline consumption requires a robust biomass-to-biofuels system-of-systems that operates in concert with the existing markets. This paper discusses employing a system dynamics approach to investigate potential market penetration scenarios for cellulosic ethanol and to help government decision makers focus on areas with greatest potential.

Bush, B.; Duffy, M.; Sandor, D.; Peterson, S.

2008-06-01T23:59:59.000Z

165

System and method to determine electric motor efficiency using an equivalent circuit  

DOE Patents (OSTI)

A system and method for determining electric motor efficiency includes a monitoring system having a processor programmed to determine efficiency of an electric motor under load while the electric motor is online. The determination of motor efficiency is independent of a rotor speed measurement. Further, the efficiency is based on a determination of stator winding resistance, an input voltage, and an input current. The determination of the stator winding resistance occurs while the electric motor under load is online.

Lu, Bin (Kenosha, WI); Habetler, Thomas G. (Snellville, GA)

2011-06-07T23:59:59.000Z

166

Abstract --The transition from a vertically integrated industry to a horizontally integrated open market system changes  

E-Print Network (OSTI)

participants and the volatility of market prices. These additional factors are significant, especially system simulation. I. INTRODUCTION he economic benefits of improved efficiency and lower price also production activities includes public information about market-clearing electricity and fuel prices

Berleant, Daniel

167

Efficient transformations from geodetic to UTM coordinate systems  

Science Conference Proceedings (OSTI)

The problem of efficiently performing transformations from geocentric to geodetic coordinates has been addressed at previous DIS (Distributed Interactive Simulation) workshops. This paper extends the work presented at the 14th DIS Workshop. As a consequence of the new algorithm for geocentric to geodetic coordinate conversion, a subsequent conversion to Universal Transverse Mercator coordinates is made considerably more efficient. No additional trigonometric or square root evaluations are required and accuracy is not degraded.

Toms, R.M.

1996-08-07T23:59:59.000Z

168

A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection  

E-Print Network (OSTI)

A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection a thermal-conscious system-level methodology to make energy-efficient voltage selection (VS) for nanometer), thermal resistance, are integrated and considered in our system models, and their impacts on energy

Wang, Yu

169

Roof-and-attic system delivers year-round efficiency | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

at ORNL improves efficiency using controls for radiation, convection, and insulation, including a passive ventilation system that pulls air from the underbelly of the...

170

Tradeoffs between Costs and Greenhouse Gas Emissions in the Design of Urban Transit Systems  

E-Print Network (OSTI)

Rail, and Diesel Multiple Units." Transportation ResearchRail Transit and Bus Rapid Transit." Transportation Researchrail and bus rapid transit over a radial public transport network." Research

Griswold, Julia Baird

2013-01-01T23:59:59.000Z

171

Energy-Efficient Spectrum Sharing in Relay-Assisted Cognitive Radio Systems  

E-Print Network (OSTI)

Energy-Efficient Spectrum Sharing in Relay-Assisted Cognitive Radio Systems (Invited Paper) Mariem of a relevant spectrum game. Two energy-efficient sources communicating with their respective destination energy-efficient sources. Keywords: resource allocation, cognitive radio, cooperative transmission, Nash

Paris-Sud XI, Université de

172

Small Hydropower Systems: Energy Efficiency and Renewable Energy Clearinghouse  

DOE Green Energy (OSTI)

This fact sheet introduces consumers to small hydropower systems, and includes information on how the systems work and how to assess a stream site for hydropower suitability.

Nachman-Hunt, N.

2001-07-05T23:59:59.000Z

173

Energy efficiency improvements in Chinese compressed air systems  

E-Print Network (OSTI)

air system assessments and energy audits based on a systemaudit. These compressed air system assessments may be conducted by compressor manufacturers/distributors or energy

McKane, Aimee; Li, Li; Li, Yuqi; Taranto, T.

2008-01-01T23:59:59.000Z

174

Transit Timing Observations from Kepler: IV. Confirmation of 4 Multiple Planet Systems by Simple Physical Models  

SciTech Connect

Eighty planetary systems of two or more planets are known to orbit stars other than the Sun. For most, the data can be sufficiently explained by non-interacting Keplerian orbits, so the dynamical interactions of these systems have not been observed. Here we present 4 sets of lightcurves from the Kepler spacecraft, which each show multiple planets transiting the same star. Departure of the timing of these transits from strict periodicity indicates the planets are perturbing each other: the observed timing variations match the forcing frequency of the other planet. This confirms that these objects are in the same system. Next we limit their masses to the planetary regime by requiring the system remain stable for astronomical timescales. Finally, we report dynamical fits to the transit times, yielding possible values for the planets masses and eccentricities. As the timespan of timing data increases, dynamical fits may allow detailed constraints on the systems architectures, even in cases for which high-precision Doppler follow-up is impractical.

Fabrycky, Daniel C.; /UC, Santa Cruz; Ford, Eric B.; /Florida U.; Steffen, Jason H.; /Fermilab; Rowe, Jason F.; /SETI Inst., Mtn. View /NASA, Ames; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Moorhead, Althea V.; /Florida U.; Batalha, Natalie M.; /San Jose State U.; Borucki, William J.; /NASA, Ames; Bryson, Steve; /NASA, Ames; Buchhave, Lars A.; /Bohr Inst. /Copenhagen U.; Christiansen, Jessie L.; /SETI Inst., Mtn. View /NASA, Ames /Caltech

2012-01-01T23:59:59.000Z

175

Implications of Low Particulate Matter Emissions on System Fuel Efficiency for High Efficiency Clean Combustion  

DOE Green Energy (OSTI)

Advanced diesel combustion regimes such as High Efficiency Clean Combustion (HECC) offer the benefits of reduced engine out NOX and particulate matter (PM) emissions. Lower PM emissions during advanced combustion reduce the demand on diesel particulate filters (DPFs) and can, thereby, reduce the fuel penalty associated with DPF regeneration. In this study, a SiC DPF was loaded and regenerated on a 1.7-liter 4-cylinder diesel engine operated in conventional and advanced combustion modes at different speed and load conditions. A diesel oxidation catalyst (DOC) and a lean NOX trap (LNT) were also installed in the exhaust stream. Five steady-state speed and load conditions were weighted to estimate Federal Test Procedure (FTP) fuel efficiency. The DPF was loaded using lean-rich cycling with frequencies that resulted in similar levels of NOX emissions downstream of the LNT. The pressure drop across the DPF was measured at a standard point (1500 rpm, 5.0 bar) before and after loading, and a P rise rate was determined for comparison between conventional and advanced combustion modes. Higher PM emissions in conventional combustion resulted in a higher rate of backpressure rise across the DPF at all of the load points leading to more frequent DPF regenerations and higher fuel penalty. The fuel penalty during conventional combustion was 4.2% compared with 3.1% for a mixture of conventional and advanced modes.

Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL

2009-01-01T23:59:59.000Z

176

PHYSICAL PROPERTIES OF THE 0.94-DAY PERIOD TRANSITING PLANETARY SYSTEM WASP-18  

SciTech Connect

We present high-precision photometry of five consecutive transits of WASP-18, an extrasolar planetary system with one of the shortest orbital periods known. Through the use of telescope defocusing we achieve a photometric precision of 0.47-0.83 mmag per observation over complete transit events. The data are analyzed using the JKTEBOP code and three different sets of stellar evolutionary models. We find the mass and radius of the planet to be M {sub b} = 10.43 +- 0.30 +- 0.24 M {sub Jup} and R {sub b} = 1.165 +- 0.055 +- 0.014 R {sub Jup} (statistical and systematic errors), respectively. The systematic errors in the orbital separation and the stellar and planetary masses, arising from the use of theoretical predictions, are of a similar size to the statistical errors and set a limit on our understanding of the WASP-18 system. We point out that seven of the nine known massive transiting planets (M {sub b} > 3 M {sub Jup}) have eccentric orbits, whereas significant orbital eccentricity has been detected for only four of the 46 less-massive planets. This may indicate that there are two different populations of transiting planets, but could also be explained by observational biases. Further radial velocity observations of low-mass planets will make it possible to choose between these two scenarios.

Southworth, John; Anderson, D. R.; Maxted, P. F. L. [Astrophysics Group, Keele University, Newcastle-under Lyme, ST5 5BG (United Kingdom); Hinse, T. C. [Armagh Observatory, College Hill, Armagh, BT61 9DG (United Kingdom); Dominik, M.; Mathiasen, M.; Browne, P. [SUPA, University of St. Andrews, School of Physics and Astronomy, North Haugh, St. Andrews, KY16 9SS (United Kingdom); Glitrup, M. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, 8000 Aarhus C (Denmark); Joergensen, U. G.; Harpsoee, K. [Niels Bohr Institute and Centre for Star and Planet Formation, University of Copenhagen, Juliane Maries vej 30, 2100 Copenhagen Oe (Denmark); Liebig, C.; Maier, G. [Astronomisches Rechen-Institut, Zentrum fuer Astronomie, Universitaet Heidelberg, Moenchhofstrasse 12-14, 69120 Heidelberg (Germany); Bozza, V.; Calchi Novati, S.; Mancini, L. [Dipartimento di Fisica 'E. R. Caianiello', Universita di Salerno, Baronissi (Italy); Burgdorf, M. [Deutsches SOFIA Institut, NASA Ames Research Center, Mail Stop 211-3, Moffett Field, CA 94035 (United States); Dreizler, S.; Hessman, F.; Hundertmark, M. [Institut fuer Astrophysik, Georg-August-Universitaet Goettingen, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany); Finet, F., E-mail: jkt@astro.keele.ac.u [Institut d'Astrophysique et de Geophysique, Universite de Liege, 4000 Liege (Belgium)

2009-12-10T23:59:59.000Z

177

Improving the Efficiency of Your Process Cooling System  

E-Print Network (OSTI)

Many industries require process cooling to achieve desired outcomes of specific processes. This cooling may come from cooling towers, once-through water, mechanical refrigeration, or cryogenic sources such as liquid nitrogen or dry ice. This paper deals primarily with mechanically-based process cooling. Based on the author's experiences, this category provides the greatest opportunity for energy efficiency improvement.

Baker, R.

2005-01-01T23:59:59.000Z

178

Efficiency of critical incident management systems: Instrument development and validation  

Science Conference Proceedings (OSTI)

There is much literature in the area of emergency response management systems. Even so, there is in general a lacuna of literature that deals with the issue of measuring the effectiveness of such systems. The aim of this study is to develop and validate ... Keywords: Critical incident management system (CIMS), Decision support, Emergency response systems, Instrument, Measurement, Media richness theory, National incident management systems (NIMS), Validation

Jin Ki Kim; Raj Sharman; H. Raghav Rao; Shambhu Upadhyaya

2007-11-01T23:59:59.000Z

179

An energy-efficient communication system for ad hoc wireless and sensor networks  

E-Print Network (OSTI)

Existing ad hoc wireless and sensor network systems often trade off energy against performance. As such, it is hard to find a single deployable system that supports high data rates while maintaining energy-efficient ...

Tetteh, William Nii Adjetey

2007-01-01T23:59:59.000Z

180

Design of control for efficiency of AUV power systems  

E-Print Network (OSTI)

The MIT Rapid Development Group designed and built an internal combustion hybrid recharging system for the REMUS 600 Autonomous Underwater Vehicle (AUV) in collaboration with the MIT Lincoln Laboratory. This power system ...

Ware, Laura M. (Laura Marie)

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Field Measurements of Heating System Efficiency in Nine Electrically-Heated Manufactured Homes.  

Science Conference Proceedings (OSTI)

This report presents the results of field measurements of heating efficiency performed on nine manufactured homes sited in the Pacific Northwest. The testing procedure collects real-time data on heating system energy use and heating zone temperatures, allowing direct calculation of heating system efficiency.

Davis, Bob; Siegel, J.; Palmiter, L.; Baylon, D.

1996-07-01T23:59:59.000Z

182

Evaluation of energy-efficiency in lighting systems using sensor networks  

Science Conference Proceedings (OSTI)

In modern energy aware buildings, lighting control systems are put in place so to maximise the energy-efficiency of the lighting system without effecting the comfort of the occupant. In many cases this involves utilising a set of presence sensors, with ... Keywords: building, decision, efficiency, energy, lighting, network, sensor, support

Declan T. Delaney; Gregory M. P. O'Hare; Antonio G. Ruzzelli

2009-11-01T23:59:59.000Z

183

High Quality Down Lighting Luminaire with 73% Overall System Efficiency  

SciTech Connect

This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion <10%. Two styles of downlights using the LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.

Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison

2010-08-31T23:59:59.000Z

184

High Quality Down Lighting Luminaire with 73% Overall System Efficiency  

Science Conference Proceedings (OSTI)

This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.

Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison

2010-08-31T23:59:59.000Z

185

Efficient optimal design of uncertain discrete time dynamical systems  

Science Conference Proceedings (OSTI)

In this paper we consider the problem of optimal design of an uncertain discrete time nonlinear dynamical system. The problem is formulated using an a-posterori design criterion, which can account for uncertainties generated by the dynamics of the system ... Keywords: Discrete time dynamical systems, Optimal design, Randomized algorithms, Uncertain parameters

Chenxi Lin; Thordur Runolfsson

2012-10-01T23:59:59.000Z

186

POEM: Power-efficient Occupancy-based Energy Management System  

E-Print Network (OSTI)

for optimally controlling HVAC systems in buildings based on actual occupancy levels. POEM is comprised for Heating Ventilation and Air-Conditioning (HVAC) systems. Current HVAC systems only condition based are then fused with an occupancy prediction model us- ing a particle filter in order to determine the most

Cerpa, Alberto E.

187

Evaluation of Hydraulic Efficiency of Disinfection Systems Based on  

E-Print Network (OSTI)

time (TDT) and the rising limb of the residence time distribution (RTD) curve. This evaluation and scalar transport dynamics and subsequent RTD curve. The main objective of this study was to analyze, primarily a pipe loop system, pressurized tank system, and baffled tank system, from their respective RTD

188

The Rossiter-McLaughlin effect and analytic radial velocity curves for transiting extrasolar planetary systems  

E-Print Network (OSTI)

A transiting extrasolar planet sequentially blocks off the light coming from the different parts of the disk of the host star in a time dependent manner. Due to the spin of the star, this produces an asymmetric distortion in the line profiles of the stellar spectrum, leading to an apparent anomaly of the radial velocity curves, known as the Rossiter - McLaughlin effect. Here, we derive approximate but accurate analytic formulae for the anomaly of radial velocity curves taking account of the stellar limb darkening. The formulae are particularly useful in extracting information of the projected angle between the planetary orbit axis and the stellar spin axis, \\lambda, and the projected stellar spin velocity, V sin I_s. We create mock samples for the radial curves for the transiting extrasolar system HD209458, and demonstrate that constraints on the spin parameters (V sin I_s, \\lambda) may be significantly improved by combining our analytic template formulae and the precision velocity curves from high-resolution spectroscopic observations with 8-10 m class telescopes. Thus future observational exploration of transiting systems using the Rossiter - McLaughlin effect is one of the most important probes to better understanding of the origin of extrasolar planetary systems, especially the origin of their angular momentum.

Yasuhiro Ohta; Atsushi Taruya; Yasushi Suto

2004-10-21T23:59:59.000Z

189

New technology can improve electric power system efficiency and ...  

U.S. Energy Information Administration (EIA)

The term "smart grid" covers a range of devices and systems that leverage recent advances in digital technology and communications to ... Developing methods for ...

190

An efficient multi-channel wireless switching system  

E-Print Network (OSTI)

the scheduling operation in wireless switching systems. Thefor the local operation between a wireless switch port andoperations in interference-rich multi-channel wireless

Shim, Jaewook

2010-01-01T23:59:59.000Z

191

Highly efficient photochemical HCOOH production from CO{sub 2} and water using an inorganic system  

SciTech Connect

We have constructed a system that uses solar energy to react CO{sub 2} with water to generate formic acid (HCOOH) at an energy conversion efficiency of 0.15%. It consists of an AlGaN/GaN anode photoelectrode and indium (In) cathode that are electrically connected outside of the reactor cell. High energy conversion efficiency is realized due to a high quantum efficiency of 28% at 300 nm, attributable to efficient electron-hole separation in the semiconductor's heterostructure. The efficiency is close to that of natural photosynthesis in plants, and what is more, the reaction product (HCOOH) can be used as a renewable energy source.

Yotsuhashi, Satoshi; Hashiba, Hiroshi; Deguchi, Masahiro; Zenitani, Yuji; Hinogami, Reiko; Yamada, Yuka [Advanced Technology Research Laboratory, Panasonic Corporation, Soraku-gun, Kyoto 619-0237 (Japan); Deura, Momoko; Ohkawa, Kazuhiro [Department of Applied Physics, Tokyo University of Science, Shinjuku, Tokyo 162-8601 (Japan)

2012-12-15T23:59:59.000Z

192

Fan System Effects: How Fan Ductwork Design Impacts Overall System Efficiency and What the Approach Should be for Optimization  

E-Print Network (OSTI)

"In order to establish the aerodynamic performance characteristics of a custom fan or even a line of fans, the accepted practice of the industry is to carry out testing on a scale model in a laboratory to develop its fan performance curve. Then by applying affinity laws in conjunction with very specific rules that address scaling issues, the performance characteristics of geometrically similar fans can be predicted. These affinity laws (frequently referred to as fan laws) also allow the performance of fans operating at different speeds or handling gases at different density values to be accurately predicted. However, it is often found that even fans with well defined and pedigreed performance curves are unable to meet their performance expectations once they are installed on the systems for which they have been sold. This is primarily due to the adverse aerodynamic impact of the inlet or outlet connections on the performance capacity of the fan and thus on the overall system efficiency. The general term for design conditions at inlets or outlets of fans that cause deficient aerodynamic performance is ‘system effects’. The characteristics of fan system effects are that they reduce fan capacity and are both velocity and geometry dependent. On the inlet side of a fan, this generally characterizes itself by a flow pattern that is highly non?uniform. On the discharge side, the high and low velocity flow streams leaving the fan may simply be prevented from redeveloping a uniform flow profile and normal static pressure conversion before encountering a disturbance. The term can also apply to system elements such as silencers, elbows and transitions. For these components, the actual pressure drop across them may be significantly higher than their calculated or rated values if the velocity profile of the entering flow is skewed or non?uniform. For either case (fan connection or system component), the result is that additional power will be required to address the flow rate required by the system. In many instances, system designers are simply unfamiliar with the importance of understanding system effects as it pertains to new fan selections and the attendant power requirements. At a minimum, a reasonable approach for new fan projects should be to establish the theoretical system effect of connection designs by using a recognized document such as Air Movement and Control Association Publication 201. The objective should be to first minimize their impact through appropriate connection design modifications in conjunction with potential fan inlet and outlet re?orientation. Once the system effects are minimized, the residual value should be applied to the fan performance specification in order to ensure that the fan is selected for the required aerodynamic capacity. For system components, an approach that has proved to be of significant value is to predict the flow pattern using computation fluid dynamics (CFD) modelling tools and in this process, the design can be tweaked until the designer finds the overall pressure drops of a system are minimized to the greatest practical extent. Similarly, CFD can be used to predict the flow profile at a fan inlet to ensure that it is as uniform as practically possible. This paper reviews the concept of system effects from the perspective of fan power requirements and provides a methodology for approaching system design from the perspective of optimizing fan energy use while achieving the required system capacity."

Martin, V.

2009-05-01T23:59:59.000Z

193

Efficiency Measures  

NLE Websites -- All DOE Office Websites (Extended Search)

recommended steam system energy efficiency measures Based on analyses implementation of steam system energy efficiency measures is driven primarily by cost metrics payback period...

194

Pipelining with common operands for power-efficient linear systems  

Science Conference Proceedings (OSTI)

We propose a systematic pipelining method for a linear system to minimize power and maximize throughput, given a constraint on the number of pipeline stages and a set of resource constraints. Unlike most existing pipelining approaches, our method takes ... Keywords: common operand, linear system, operand sharing, pipelining, power

Daehong Kim; Dongwan Shin; Kiyoung Choi

2005-09-01T23:59:59.000Z

195

POEM: power-efficient occupancy-based energy management system  

Science Conference Proceedings (OSTI)

Buildings account for 40% of US primary energy consumption and 72% of electricity. Of this total, 50% of the energy consumed in buildings is used for Heating Ventilation and Air-Conditioning (HVAC) systems. Current HVAC systems only condition based on ... Keywords: HVAC, energy savings, occupancy, ventilation

Varick L. Erickson; Stefan Achleitner; Alberto E. Cerpa

2013-04-01T23:59:59.000Z

196

An efficient system for collaboration in tele-immersive environments  

Science Conference Proceedings (OSTI)

The paper describes the development of a high-performance system for visualizing complex scientific models in real-time. The architecure of the system is a client/server model, in which the simulator generates lists of 3D graphics objects in parallel ...

N. Jensen; S. Olbrich; H. Pralle; S. Raasch

2002-09-01T23:59:59.000Z

197

Direct Digital Control in Air Conditioning Systems for Energy Efficiency  

E-Print Network (OSTI)

With the rapid development of Intelligent Buildings (IB), the Building Automation System (BAS) has come to control and manage the equipment in the building more and more scientifically, economically and rationally, which can not only raise the function and the level of the building, but also save energy. At present, air-conditioning design in internal commercial buildings is becoming more complex and enormous. The proportion of air conditioning systems in the whole building is getting larger. In order to control and manage the air-conditioning systems effectively and take full use of energy-saving technology, we apply computer control to the system of air automation control. This paper discusses direct digital control (DDC) in the air conditioning system in buildings.

Liu, W.; Ye, A.; Li, D.

2006-01-01T23:59:59.000Z

198

Energy and Spectral Efficiency of Very Large Multiuser MIMO Systems  

E-Print Network (OSTI)

A multiplicity of autonomous terminals simultaneously transmits data streams to a compact array of antennas. The array uses imperfect channel-state information derived from transmitted pilots to extract the individual data streams. The power radiated by the terminals can be made inversely proportional to the square-root of the number of base station antennas with no reduction in performance. In contrast if perfect channel-state information were available the power could be made inversely proportional to the number of antennas. Lower capacity bounds for maximum-ratio combining (MRC), zero-forcing (ZF) and minimum mean-square error (MMSE) detection are derived. A MRC receiver normally performs worse than ZF and MMSE. However as power levels are reduced, the cross-talk introduced by the inferior maximum-ratio receiver eventually falls below the noise level and this simple receiver becomes a viable option. The tradeoff between the energy efficiency (as measured in bits/J) and spectral efficiency (as measured in b...

Ngo, Hien Quoc; Marzetta, Thomas L

2011-01-01T23:59:59.000Z

199

Biological optimization systems for enhancing photosynthetic efficiency and methods of use  

DOE Patents (OSTI)

Biological optimization systems for enhancing photosynthetic efficiency and methods of use. Specifically, methods for enhancing photosynthetic efficiency including applying pulsed light to a photosynthetic organism, using a chlorophyll fluorescence feedback control system to determine one or more photosynthetic efficiency parameters, and adjusting one or more of the photosynthetic efficiency parameters to drive the photosynthesis by the delivery of an amount of light to optimize light absorption of the photosynthetic organism while providing enough dark time between light pulses to prevent oversaturation of the chlorophyll reaction centers are disclosed.

Hunt, Ryan W.; Chinnasamy, Senthil; Das, Keshav C.; de Mattos, Erico Rolim

2012-11-06T23:59:59.000Z

200

Dynamic Phase Transitions In The Spin-2 Ising System Under An Oscillating Magnetic Field Within The Effective-Field Theory  

SciTech Connect

The dynamic phase transitions are studied in the spin-2 Ising model under a time-dependent oscillating magnetic field by using the effective-field theory with correlations. The effective-field dynamic equation is derived by employing the Glauber transition rates and the phases in the system are obtained by solving this dynamic equation. The nature (first- or second-order) of the dynamic phase transition is characterized by investigating the thermal behavior of the dynamic order parameter and the dynamic phase transition temperatures are obtained. The dynamic phase diagrams are presented in (T/zJ, h/zJ) plane.

Ertas, Mehmet; Keskin, Mustafa [Department of Physics, Erciyes University, 38039 Kayseri (Turkey); Deviren, Bayram [Department of Physics, Nevsehir University, 50300 Nevsehir (Turkey)

2010-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Direct address translation for virtual memory in energy-efficient embedded systems  

Science Conference Proceedings (OSTI)

This article presents a methodology for virtual memory support in energy-efficient embedded systems. A holistic approach is proposed, where the combined efforts of compiler, operating system, and hardware architecture achieve a significant system power ... Keywords: Low-power embedded systems, address translation, virtual memory

Xiangrong Zhou; Peter Petrov

2008-12-01T23:59:59.000Z

202

High Efficiency, Ultra-Low Emission, Integrated Process Heater System  

Science Conference Proceedings (OSTI)

The team of TIAX LLC, ExxonMobil Research and Engineering Company, and Callidus Technologies, LLC conducted a six-year program to develop an ultra-low emission process heater burner and an advanced high efficiency heater design. This project addresses the critical need of process heater operators for reliable, economical emission reduction technologies to comply with stringent emission regulations, and for heater design alternatives that reduce process heater energy requirements without significant cost increase. The key project targets were NOx emissions of 10 ppm (@ 3% O2), and a heater thermal efficiency of 95 percent. The ultra low NOx burner was developed through a series of pilot-scale and field tests combined with computational fluid dynamic modeling to arrive at simultaneous low emissions and suitable flame shape and stability. Pilot scale tests were run at TIAX, at the 2 MMBtu/hr scale, and at Callidus at 8 MMBtu/hr. The full scale burner was installed on a 14 burner atmospheric pipestill furnace at an ExxonMobil refinery. A variety of burner configurations, gas tips and flame stabilizers were tested to determine the lowest emissions with acceptable flame shape and stability. The resulting NOx emissions were 22 ppm on average. Starting in 2001, Callidus commercialized the original ultra low NOx burner and made subsequent design improvements in a series of commercial burners evolving from the original concept and/or development. Emissions in the field with the ultra low-NOx burner over a broad spectrum of heater applications have varied from 5 ppm to 30 ppm depending on heater geometry, heater service, fuel and firing capacity. To date, 1550 of the original burners, and 2500 of subsequent generation burners have been sold by Callidus. The advanced heater design was developed by parametric evaluations of a variety of furnace and combustion air preheater configurations and technologies for enhancing convective and radiative heat transfer. The design evolution relied heavily on computational fluid dynamic predictions of design alternatives. The final design features modular separate radiant cells, each with one and two-side fired vertical tubes. The convection section configuration is vertical tube banks enclosed in the radiant channels. Commercial modular plate air preheaters are used. The predicted performance for the integrated advanced heater and Callidus burner is 95 percent efficiency with 9 ppm NOx emissions firing natural gas, and 12 ppm firing refinery gas. The total erected cost is less than a conventional heater with combustion air preheat.

Mason, Howard; Boral, Anindya; Chhotray, San; Martin, Matthew

2006-06-19T23:59:59.000Z

203

Transmission System Efficiency and Utilization Improvement: Summary of R&D Activity and Demonstration Projects  

Science Conference Proceedings (OSTI)

  This report compiles and summarizes the activities, findings, and main conclusions derived from the development of EPRI R&D Program 172 - Efficient Transmission Systems for a Carbon-Constrained World.BackgroundEPRI R&D Program 172, Efficient Transmission Systems for a Carbon-Constrained World, was initiated in 2008 and finalized in 2012. The main objective of the program was to assist utilities to prepare for operating a power-delivery system ...

2012-12-31T23:59:59.000Z

204

Nutrient use efficiency in bioenergy cropping systems: Critical research questions  

E-Print Network (OSTI)

x giganteus. Biomass Bioenergy 12:21-24. Christian, D.G. ,for-biofuels systems. Biomass Bioenergy Gentry, L.E. , F.E.cynosuroides. Biomass Bioenergy 12:419-428. Brejda, J.J.

Brouder, Sylvie; Volenec, Jeffrey J; Turco, Ronald; Smith, Douglas R; Ejeta, Gebisa

2009-01-01T23:59:59.000Z

205

Pulp and Paper Mills: Profiting from Efficient Motor System Use  

NLE Websites -- All DOE Office Websites (Extended Search)

spends 3.6 billion or about 2.6% of its overall operating costs to operate electric motor systems-higher than any other 2- digit manufacturing SIC. Opportunities to effectively...

206

Energy Efficiency and Reliability in Wireless Biomedical Implant Systems  

E-Print Network (OSTI)

The use of wireless implant technology requires correct delivery of the vital physiological signs of the patient along with the energy management in power-constrained devices. Toward these goals, we present an augmentation protocol for the physical layer of the Medical Implant Communications Service (MICS) with focus on the energy efficiency of deployed devices over the MICS frequency band. The present protocol uses the rateless code with the Frequency Shift Keying (FSK) modulation scheme to overcome the reliability and power cost concerns in tiny implantable sensors due to the considerable attenuation of propagated signals across the human body. In addition, the protocol allows a fast start-up time for the transceiver circuitry. The main advantage of using rateless codes is to provide an inherent adaptive duty-cycling for power management, due to the flexibility of the rateless code rate. Analytical results demonstrate that an 80% energy saving is achievable with the proposed protocol when compared to the IE...

Abouei, Jamshid; Plataniotis, Konstantinos N; Pasupathy, Subbarayan

2011-01-01T23:59:59.000Z

207

The Spin-Orbit Alignment of the HD17156 Transiting Eccentric Planetary System  

E-Print Network (OSTI)

We present high precision radial velocity observations of HD17156 during a transit of its eccentric Jovian planet. In these data, we detect the Rossiter-McLaughlin effect, which is an apparent perturbation in the velocity of the star due to the progressive occultation of part of the rotating stellar photosphere by the transiting planet. This system had previously been reported by Narita et al. (2008) to exhibit a lambda = 62 +/- 25 degree misalignment of the projected planetary orbital axis and the stellar rotation axis. We model our data, along with the Narita et al. data, and obtain lambda = 9.4 +/- 9.3 degrees for the combined data set. We thus conclude that the planetary orbital axis is actually very well aligned with the stellar rotation axis.

William D. Cochran; Seth Redfield; Michael Endl; Anita L. Cochran

2008-06-25T23:59:59.000Z

208

High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

April 15. 2013 | Singh April 15. 2013 | Singh * Thermal modeling will be conducted to establish the benefits of using a high thermal conducting graphite foams in conjunction with PCM and to develop a design for a laboratory scale prototype. * Variety of characterizations will be carried out to qualify the materials (PCMs, alloys, coatings) for the prototype construction. * Process to infiltrate selected PCM into the foam will be developed. * Using the appropriate brazing/joining techniques, prototype will be assembled. * Performance testing of the TES system prototype to ensure a full- scale system will meet the SunShot goals. * Complete cost analysis of the proposed TES system * Complete laboratory scale prototype design * Develop SiC coating using polycarbosilanes for graphite

209

Starter systems designed for efficient air/gas comsumption  

Science Conference Proceedings (OSTI)

This paper examines engine starting systems designed by Pow-R-Quik. Pow-R-Quik's most recent product line includes several models that are designed to start most diesel and natural gas engines. Pow-R-Quick also offers air starting systems for a wide range of gas turbine applications. The model DS16, air or gas starter, is designed for engines with a displacement up to 500 cid diesel and up to 1000 cid natural gas. The DS60 model is also an air or gas operated starter with specially designed heavy duty bearings for maximum performance. To prove out starter durability and performance, Pow-R-Quik has installed three fully instrumented diesel engine test cells. The number of starts that can be achieved ranges from zero to 99,000. The system can be set to regulate the air for low or high pressure starts, control the lubricant, etc.

Not Available

1985-05-01T23:59:59.000Z

210

A high-efficiency indirect lighting system utilizing the solar 1000 sulfur lamp  

SciTech Connect

High-lumen light sources represent unique challenges and opportunities for the design of practical and efficient interior lighting systems. High-output sources require a means of large-scale distribution and avoidance of high-luminance glare while providing efficient delivery. An indirect lighting system has been developed for use with a 1,000 Watt sulfur lamp that efficiently utilizes the high-output source to provide quality interior lighting. This paper briefly describes the design and initial testing of this new system.

Siminovitch, M.; Gould, C.; Page, E.

1997-06-01T23:59:59.000Z

211

Highly-efficient noise-assisted energy transport in classical oscillator systems  

E-Print Network (OSTI)

Photosynthesis is a biological process that involves the highly-efficient transport of energy captured from the sun to a reaction center, where conversion into useful biochemical energy takes place. Even though one can always use a quantum perspective to describe any physical process, since everything follows the laws of Quantum Mechanics, is the use of quantum theory imperative to explain this high efficiency? Several theoretical studies suggest that the high efficiency can only be understood as a result of the interplay between the quantum coherent evolution of the photosynthetic system, and noise introduced by its surrounding environment. Notwithstanding, we show here that noise-assisted highly-efficient energy transport can be found as well in purely classical systems; therefore, we might conclude that high efficiency energy transfer in photosynthetic systems could also be anticipated by classical models, without the need to resorting to quantum effects. Strikingly, the wider scope of applicability of the...

León-Montiel, R de J

2013-01-01T23:59:59.000Z

212

Energy Efficient Free Cooling System for Data Centers  

Science Conference Proceedings (OSTI)

A data center is a facility used to keep computer related equipments. It is estimated that heat production rate of the data center is doubled in every two years and hence the inevitability of the cooling system gets increased. In due course power consumption ... Keywords: Performance ratio, Water Economizer, Air Economizer, Energy Consumption, Data Center

Christy Sujatha D.; Satheesh Abimannan

2011-11-01T23:59:59.000Z

213

Open source tool for energy saving and efficient system management  

Science Conference Proceedings (OSTI)

In order to improve power quality (PQ) techniques, efforts are made to develop smart sensors that can report near real-time data. Proprietary software and hardware on dedicated computers or servers processes these data and shows relevant information ... Keywords: arm architecture, embedded systems, energy saving optimization, power quality optimization

Consolación Gil; Pedro Sánchez; Francisco G. Montoya; Antonio L. Márquez

2011-07-01T23:59:59.000Z

214

Mesoscale to Submesoscale Transition in the California Current System. Part I: Flow Structure, Eddy Flux, and Observational Tests  

Science Conference Proceedings (OSTI)

In computational simulations of an idealized subtropical eastern boundary upwelling current system, similar to the California Current, a submesoscale transition occurs in the eddy variability as the horizontal grid scale is reduced to O(1) km. ...

X. Capet; J. C. McWilliams; M. J. Molemaker; A. F. Shchepetkin

2008-01-01T23:59:59.000Z

215

Technology transition in the national air transportation system : market failure and game theoretic analysis with application to ADS-B  

E-Print Network (OSTI)

This research analyzes the problem of technology transition in the national air transportation system, focusing on the implementation of Automatic Dependent Surveillance-Broadcast (ADS-B). ADS-B is a key technology in the ...

Hu, Xiaojie

2008-01-01T23:59:59.000Z

216

The planning and analysis implications of automated data collection systems : rail transit OD matrix inference and path choice modeling examples  

E-Print Network (OSTI)

(cont.) by presenting two case studies both in the context of the Chicago Transit Authority. One study proposes an enhanced method of inferring the rail trip OD matrix from an origin-only AFC system to replace the routine ...

Zhao, Jinhua, 1977-

2004-01-01T23:59:59.000Z

217

Self-Adjustable Trust-Based Energy Efficient Routing for Smart Grid Systems  

Science Conference Proceedings (OSTI)

Smart Grid is the trend of next generation electrical power system which makes the power grid intelligent and energy efficient. It requires high level of network reliability to support two-way communication among electrical services, electrical units ... Keywords: Smart Grid, wireless mesh network, trust-based geographical routing, vulnearabilities and attacks, energy efficiency

Ming Xiang; Quan Bai; William Liu

2012-12-01T23:59:59.000Z

218

Energy Aware Paradigm for Energy Efficient ICT: a Systemic Approach Sergio Ricciardi  

E-Print Network (OSTI)

Energy Aware Paradigm for Energy Efficient ICT: a Systemic Approach Sergio Ricciardi Technical) Jordi Girona 3 08034 Barcelona, Spain +34 93 4016982 pareta@ac.upc.edu ABSTRACT Energy is imposing as the new constraint in the ICT sector and the problem of energy efficient in ICT has consequently arisen

Politècnica de Catalunya, Universitat

219

Efficiency of a hybrid-type plasma-assisted fuel reformation system  

Science Conference Proceedings (OSTI)

The major advantages of a new plasma-assisted fuel reformation system are its cost effectiveness and technical efficiency. Applied Plasma Technologies has proposed its new highly efficient hybrid-type plasma-assisted system for organic fuel combustion and gasification. The system operates as a multimode multipurpose reactor in a wide range of plasma feedstock gases and turndown ratios. This system also has convenient and simultaneous feeding of several reagents in the reaction zone such as liquid fuels, coal, steam, and air. A special methodology has been developed for such a system in terms of heat balance evaluation and optimization. This methodology considers all existing and possible energy streams, which could influence the system's efficiency. The developed hybrid-type plasma system could be suitable for combustion applications, mobile and autonomous small- to mid-size liquid fuel and coal gasification modules, hydrogen-rich gas generators, waste-processing facilities, and plasma chemical reactors.

Matveev, I.B.; Serbin, S.I.; Lux, S.M. [Applied Plasma Technologies, Mclean, VA (USA)

2008-12-15T23:59:59.000Z

220

Commercial high efficiency dehumidification systems using heat pipes  

SciTech Connect

An improved heat pipe design using separately connected two-section one-way flow heat pipes with internal microgrooves instead of wicks is described. This design is now commercially available for use to increase the dehumidification capacity of air conditioning systems. The design also includes a method of introducing fresh air into buildings while recovering heat and controlling the humidity of the incoming air. Included are applications and case studies, load calculations and technical data, and installation, operation, and maintenance information.

1993-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Dynamical systems in nanophotonics: From energy efficient modulators to light forces and optomechanics  

E-Print Network (OSTI)

We demonstrate novel device concepts based on rigorous design of the dynamics of resonant nanophotonic systems, such as dispersionless resonant switches and energy-efficient mo-dulator architectures, slow-light cells, and ...

Kaertner, Franz X.

222

Harnessing waste heat and reducing wasted lighting : three mechanical structures for efficient energy systems  

E-Print Network (OSTI)

This thesis presents three mechanical structures designed for efficient energy systems. In [3], Cooley presents a modification of a fluorescent lamp which allows it to detect nearby occupants and dim itself automatically. ...

Stronger, Brad A

2008-01-01T23:59:59.000Z

223

Transit Timing Observations from Kepler: II. Confirmation of Two Multiplanet Systems via a Non-parametric Correlation Analysis  

SciTech Connect

We present a new method for confirming transiting planets based on the combination of transit timing variations (TTVs) and dynamical stability. Correlated TTVs provide evidence that the pair of bodies are in the same physical system. Orbital stability provides upper limits for the masses of the transiting companions that are in the planetary regime. This paper describes a non-parametric technique for quantifying the statistical significance of TTVs based on the correlation of two TTV data sets. We apply this method to an analysis of the transit timing variations of two stars with multiple transiting planet candidates identified by Kepler. We confirm four transiting planets in two multiple planet systems based on their TTVs and the constraints imposed by dynamical stability. An additional three candidates in these same systems are not confirmed as planets, but are likely to be validated as real planets once further observations and analyses are possible. If all were confirmed, these systems would be near 4:6:9 and 2:4:6:9 period commensurabilities. Our results demonstrate that TTVs provide a powerful tool for confirming transiting planets, including low-mass planets and planets around faint stars for which Doppler follow-up is not practical with existing facilities. Continued Kepler observations will dramatically improve the constraints on the planet masses and orbits and provide sensitivity for detecting additional non-transiting planets. If Kepler observations were extended to eight years, then a similar analysis could likely confirm systems with multiple closely spaced, small transiting planets in or near the habitable zone of solar-type stars.

Ford, Eric B.; /Florida U.; Fabrycky, Daniel C.; /Lick Observ.; Steffen, Jason H.; /Fermilab; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Fressin, Francois; /Harvard-Smithsonian Ctr. Astrophys.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Lissauer, Jack J.; /NASA, Ames; Moorhead, Althea V.; /Florida U.; Morehead, Robert C.; /Florida U.; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Rowe, Jason F.; /NASA, Ames /SETI Inst., Mtn. View /San Diego State U., Astron. Dept.

2012-01-01T23:59:59.000Z

224

ALTERNATE HIGH EFFICIENCY PARTICULATE AIR (HEPA) FILTRATION SYSTEM  

SciTech Connect

In Phase IIA of this project, CeraMem has further developed and scaled up ceramic HEPA filters that are appropriate for use on filtration of vent gas from HLW tanks at DOE sites around the country. This work included procuring recrystallized SiC monoliths, developing membrane and cement materials, and defining a manufacturing process for the production of prototype full sizes HEPA filters. CeraMem has demonstrated that prototype full size filters can be manufactured by producing 9 full size filters that passed DOP aerosol testing at the Oak Ridge Filter Test Facility. One of these filters was supplied to the Savannah River Technical Center (SRTC) for process tests using simulated HLW tank waste. SRTC has reported that the filter was regenerable (with some increase in pressure drop) and that the filter retained its HEPA retention capability. CeraMem has also developed a Regenerable HEPA Filter System (RHFS) design and acceptance test plan that was reviewed by DOE personnel. The design and acceptance test plan form the basis of the system proposal for follow-on work in Phase IIB of this project.

Bruce Bishop; Robert Goldsmith; Karsten Nielsen; Phillip Paquette

2002-08-16T23:59:59.000Z

225

Improving the Water Efficiency of Cooling Production System  

E-Print Network (OSTI)

For most of the time, cooling towers (CTs) of cooling systems operate under partial load conditions and by regulating the air circulation with a variable frequency drive (VFD), significant reduction in the fan power can be achieved. In Kuwait and other counties of Arabian Peninsula, reduced airflow can lead to reduction in water consumption as well, since during the summer season, the dry bulb temperature of the ambient air is higher than the incoming hot water temperature, and the air undergoes sensible cooling. This paper presents the findings of a study conducted in the Avenues mall, Kuwait. Initially, the CTs operated only at high speed, and on a typical summer day nearly one fourth of the make-up water was used for self cooling of air. The study based on measured data revealed that the use of VFD can reduce the water wastage for self-cooling of air by as much as 75% and overall water consumption by 18.6% while keeping the cooling system performance at design level.

Maheshwari, G.; Al-Hadban, Y.; Al-Taqi, H. H.; Alasseri, R.

2010-01-01T23:59:59.000Z

226

The Liquid-Gas Phase Transitions in a Multicomponent Nuclear System with Coulomb and Surface Effects  

E-Print Network (OSTI)

The liquid-gas phase transition is studied in a multi-component nuclear system using a local Skyrme interaction with Coulomb and surface effects. Some features are qualitatively the same as the results of Muller and Serot which uses relativistic mean field without Coulomb and surface effects. Surface tension brings the coexistance binodal surface to lower pressure. The Coulomb interaction makes the binodal surface smaller and cause another pair of binodal points at low pressure and large proton fraction with less protons in liquid phase and more protons in gas phase.

S. J. Lee; A. Z. Mekjian

2000-06-29T23:59:59.000Z

227

Liquid-gas phase transition and Coulomb instability of asymmetric nuclear systems  

E-Print Network (OSTI)

We use a chiral SU(3) quark mean field model to study the properties of nuclear systems at finite temperature. The liquid-gas phase transition of symmetric and asymmetric nuclear matter is discussed. For two formulations of the model the critical temperature, $T_c$, for symmetric nuclear matter is found to be 15.8 MeV and 17.9 MeV. These values are consistent with those derived from recent experiments. The limiting temperatures for finite nuclei are in good agreement with the experimental points.

P. Wang; D. B. Leinweber; A. W. Thomas; A. G. Williams

2004-07-20T23:59:59.000Z

228

Liquid-Gas Phase Transition and Instabilities in Asymmetric Two Component Systems  

E-Print Network (OSTI)

The liquid-gas phase transition and associated instability in two component systems are investigated using a mean field theory. The importance of the role of both the Coulomb force and symmetry energy terms are studied. The addition of the Coulomb terms bring asymmetry into a mean field and thus result in important differences with previous approaches which did not include such terms. The Coulomb effects modify the chemical instability and mechanical instability domains shifting many features away from proton fraction point y=1/2 to a value closer to the valley of \\beta stability. These features are discussed in detail.

S. J. Lee; A. Z. Mekjian

2002-10-12T23:59:59.000Z

229

Using System Dynamics to Model the Transition to Biofuels in the United States  

DOE Green Energy (OSTI)

Today, the U.S. consumes almost 21 million barrels of crude oil per day; approximately 60% of the U.S. demand is supplied by imports. The transportation sector alone accounts for two-thirds of U.S. petroleum use. Biofuels, liquid fuels produced from domestically-grown biomass, have the potential to displace about 30% of current U.S. gasoline consumption. Transitioning to a biofuels industry on this scale will require the creation of a robust biomass-to-biofuels system-of-systems that operates in concert with the existing agriculture, forestry, energy, and transportation markets. The U.S. Department of Energy is employing a system dynamics approach to investigate potential market penetration scenarios for cellulosic ethanol, and to aid decision makers in focusing government actions on the areas with greatest potential to accelerate the deployment of biofuels and ultimately reduce the nationpsilas dependence on imported oil.

Bush, B.; Duffy, M.; Sandor, D.; Peterson, S.

2008-01-01T23:59:59.000Z

230

Helium Recovery in the LHC Cryogenic System following Magnet Resistive Transitions  

E-Print Network (OSTI)

A resistive transition (quench) of the Large Hadron Collider magnets provokes the expulsion of helium from the magnet cryostats to the helium recovery system. A high-volume, vacuum-insulated recovery line connected to several uninsulated medium-pressure gas storage tanks, forms the main constituents of the system. Besides a dedicated hardware configuration, helium recovery also implies specific procedures that should follow a quench, in order to conserve the discharged helium and possibly make use of its refrigeration capability. The amount of energy transferred after a quench from the magnets to the helium leaving the cold mass has been estimated on the basis of experimental data. Based on these data, the helium thermodynamic state in the recovery system is calculated using a lumped parameter approach. The LHC magnet quenches are classified ina parametric way from their cryogenic consequences and procedures that should follow the quench are proposed.

Chorowski, M; Serio, L; Tavian, L; Wagner, U; Van Weelderen, R

1998-01-01T23:59:59.000Z

231

Pulp and Paper Mills: Profiting for Efficient Motor System Use | ENERGY  

NLE Websites -- All DOE Office Websites (Extended Search)

Pulp and Paper Mills: Profiting for Efficient Motor System Use Pulp and Paper Mills: Profiting for Efficient Motor System Use Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In This Section Campaigns Commercial building design Communications resources Energy management guidance Financial resources Portfolio Manager Products and purchasing Recognition Research and reports Service and product provider (SPP) resources

232

Measurement of the Rossiter--McLaughlin Effect in the Transiting Exoplanetary System TrES-1  

E-Print Network (OSTI)

We report a measurement of the Rossiter--McLaughlin effect in the transiting extrasolar planetary system TrES-1, via simultaneous spectroscopic and photometric observations with the Subaru and MAGNUM telescopes. By modeling the radial velocity anomaly that was observed during a transit, we determine the sky-projected angle between the stellar spin axis and the planetary orbital axis to be $\\lambda = 30 \\pm 21$ [deg]. This is the third case for which $\\lambda$ has been measured in a transiting exoplanetary system, and the first demonstration that such measurements are possible for relatively faint host stars ($V \\sim 12$, as compared to $V \\sim 8$ for the other systems). We also derive a time of mid-transit, constraints on the eccentricity of the TrES-1b orbit ($e = 0.048 \\pm 0.025$), and upper limits on the mass of the Trojan companions ($\\lesssim$14 $M_{\\oplus}$) at the 3$\\sigma$ level.

Norio Narita; Keigo Enya; Bun'ei Sato; Yasuhiro Ohta; Joshua N. Winn; Yasushi Suto; Atsushi Taruya; Edwin L. Turner; Wako Aoki; Motohide Tamura; Toru Yamada; Yuzuru Yoshii

2007-02-27T23:59:59.000Z

233

System transition : dynamics of change in the US air transportation system  

E-Print Network (OSTI)

The US Air Transportation System is currently facing a number of challenges including an increasing demand for travel and growing environmental requirements. In order to successfully meet future needs, the system will need ...

Mozdzanowska, Aleksandra L. (Aleksandra Ludmila), 1979-

2008-01-01T23:59:59.000Z

234

Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems  

DOE Green Energy (OSTI)

Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the conversion of hydrocarbons to useful products. The goals of the research are to develop and understand single-site homogeneous catalysts for the conversion of readily available hydrocarbons into useful materials. A detailed understanding of these catalytic reactions could lead to the development of catalysts with improved activity, longevity and selectivity. Such transformations could reduce the environmental impact of hydrocarbon functionalization, conserve energy and valuable fossil resources and provide new technologies for the production of liquid fuels. This project is a collaborative effort that incorporates both experimental and computational studies to understand the details of transition metal catalyzed C-H activation and C-C bond forming reactions with olefins. Accomplishments of the current funding period include: (1) We have completed and published studies of C-H activation and catalytic olefin hydroarylation by TpRu{l_brace}P(pyr){sub 3}{r_brace}(NCMe)R (pyr = N-pyrrolyl) complexes. While these systems efficiently initiate stoichiometric benzene C-H activation, catalytic olefin hydroarylation is hindered by inhibition of olefin coordination, which is a result of the steric bulk of the P(pyr){sub 3} ligand. (2) We have extended our studies of catalytic olefin hydroarylation by TpRu(L)(NCMe)Ph systems to L = P(OCH{sub 2}){sub 3}CEt. Thus, we have now completed detailed mechanistic studies of four systems with L = CO, PMe{sub 3}, P(pyr){sub 3} and P(OCH{sub 2}){sub 3}CEt, which has provided a comprehensive understanding of the impact of steric and electronic parameters of 'L' on the catalytic hydroarylation of olefins. (3) We have completed and published a detailed mechanistic study of stoichiometric aromatic C-H activation by TpRu(L)(NCMe)Ph (L = CO or PMe{sub 3}). These efforts have probed the impact of functionality para to the site of C-H activation for benzene substrates and have allowed us to develop a detailed model of the transition state for the C-H activation process. These results have led us to conclude that the C-H bond cleavage occurs by a {sigma}-bond metathesis process in which the C-H transfer is best viewed as an intramolecular proton transfer. (4) We have completed studies of Ru complexes possessing the N-heterocyclic carbene IMes (IMes = 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene). One of these systems is a unique four-coordinate Ru(II) complex that catalyzes the oxidative hydrophenylation of ethylene (in low yields) to produce styrene and ethane (utilizing ethylene as the hydrogen acceptor) as well as the hydrogenation of olefins, aldehydes and ketones. These results provide a map for the preparation of catalysts that are selective for oxidative olefin hydroarylation. (5) The ability of TpRu(PMe{sub 3})(NCMe)R systems to activate sp{sup 3} C-H bonds has been demonstrated including extension to subsequent C-C bond forming steps. These results open the door to the development of catalysts for the functionalization of more inert C-H bonds. (6) We have discovered that Pt(II) complexes supported by simple nitrogen-based ligands serve as catalysts for the hydroarylation of olefins. Given the extensive studies of Pt-based catalytic C-H activation, we believe these results will provide an entry point into an array of possible catalysts for hydrocarbon functionalization.

T. Brent Gunnoe

2011-02-17T23:59:59.000Z

235

Structural Transitions, Melting, and Intermediate Phases for Stripe and Clump Forming Systems  

E-Print Network (OSTI)

We numerically examine the properties of a two-dimensional system of particles which have competing long range repulsive and short range attractive interactions as a function of density and temperature. For increasing density, there are well defined transitions between a low density clump phase, an intermediate stripe phase, an anticlump phase, and a high density uniform phase. To characterize the transitions between these phases we propose several measures which take into account the different length scales in the system. For increasing temperature, we find an intermediate phase that is liquid-like on the short length scale of interparticle spacing but solid-like on the larger length scale of the clump, stripe, or anticlump pattern. This intermediate phase persists over the widest temperature range in the stripe state when the local particle lattice within an individual stripe melts well below the temperature at which the entire stripe structure breaks down, and is characterized by intra-stripe diffusion of particles without inter-stripe diffusion. This is followed at higher temperatures by the onset of inter-stripe diffusion in an anisotropic diffusion phase, and then by breakup of the stripe structure. We identify the transitions between these regimes through diffusion, specific heat, and energy fluctuation measurements, and find that within the intra-stripe liquid regime, the excess entropy goes into disordering the particle arrangements within the stripe rather than affecting the stripe structure itself. The clump and anticlump phases also show multiple temperature-induced diffusive regimes which are not as pronounced as those of the stripe phase.

C. J. Olson Reichhardt; C. Reichhardt; A. R. Bishop

2010-05-05T23:59:59.000Z

236

Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways  

NLE Websites -- All DOE Office Websites (Extended Search)

Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways to Provide Comfort Indoors Speaker(s): Hui Zhang Date: October 9, 2012 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Rongxin Yin This presentation describes energy efficient approaches to provide comfort in offices by creating non-uniform and transient thermal environments. The presentation will describe 1) distributions and characteristics of thermoreceptors of human body, 2) comfort responses of people exposed to complex thermal environments, 3) concept of "alliesthesia", 4) personal comfort systems developed by CBE, 5) their energy efficiency and demand response potential, and 6) the CBE advanced thermal comfort model. A recording of this seminar is available at: https://vimeo.com/51536661

237

Evaluating Rail Transit Criticism  

E-Print Network (OSTI)

This report evaluates criticism of rail transit systems. It examines claims that rail transit is ineffective at increasing public transit ridership and improving transportation system performance, that rail transit investments are not cost effective, and that transit is an outdated form of transportation. It finds that critics often misrepresent issues and use biased and inaccurate analysis. This is a companion to the report Rail Transit in

Todd Litman

2010-01-01T23:59:59.000Z

238

Nanocoatings for High-Efficiency Industrial and Tooling Systems  

Science Conference Proceedings (OSTI)

This industry-driven project was the result of a successful response by Eaton Corporation to a DOE/ITP Program industry call. It consisted of three phases in which ORNL participated. In addition to Eaton Corporation and ORNL (CRADA), the project team included Ames Laboratory, who developed the underlying concept for aluminum-magnesium-boron based nanocomposite coatings [1], and Greenleaf, a small tooling manufacturer in western Pennsylvania. This report focuses on the portion of this work that was conducted by ORNL in a CRADA with Eaton Corporation. A comprehensive final report for the entire effort, which ended in September 2010, has been prepared by Eaton Corporation. Phase I, “Proof of Concept” ran for one year (September 1, 2006 to September 30, 2007) during which the applicability of AlMgB14 single-phase and nanocomposite coatings on hydraulic material coupons and components as well as on tool inserts was demonstrated.. The coating processes used either plasma laser deposition (PLD) or physical vapor deposition (PVD). During Phase I, ORNL conducted laboratory-scale pin-on-disk and reciprocating pin-on-flat tests of coatings produced by PLD and PVD. Non-coated M2 tool steel was used as a baseline for comparison, and the material for the sliding counterface was Type 52100 bearing steel since it simulated the pump materials. Initial tests were run mainly in a commercial hydraulic fluid named Mobil DTE-24, but some tests were later run in a water-glycol mixture as well. A tribosystem analysis was conducted to define the operating conditions of pump components and to help develop simulative tests in Phase II. Phase II, “Coating Process Scale-up” was intended to use scaled-up process to generate prototype parts. This involved both PLD practices at Ames Lab, and a PVD scale-up study at Eaton using its production capable equipment. There was also a limited scale-up study at Greenleaf for the tooling application. ORNL continued to conduct friction and wear tests on process variants and developed tests to better simulate the applications of interest. ORNL also employed existing lubrication models to better understand hydraulic pump frictional behavior and test results. Phase III, “Functional Testing” focused on finalizing the strategy for commercialization of AlMgB14 coatings for both hydraulic and tooling systems. ORNL continued to provide tribology testing and analysis support for hydraulic pump applications. It included both laboratory-scale coupon testing and the analysis of friction and wear data from full component-level tests performed at Eaton Corp. Laboratory-scale tribology test methods are used to characterize the behavior of nanocomposite coatings prior to running them in full-sized hydraulic pumps. This task also includes developing tribosystems analyses, both to provide a better understanding of the performance of coated surfaces in alternate hydraulic fluids, and to help design useful laboratory protocols. Analysis also includes modeling the lubrication conditions and identifying the physical processes by which wear and friction of the contact interface changes over time. This final report summarizes ORNL’s portion of the nanocomposite coatings development effort and presents both generated data and the analyses that were used in the course of this effort.

Blau, P; Qu, J.; Higdon, C. (Eaton Corporation)

2011-02-01T23:59:59.000Z

239

Bell-CHSH function approach to quantum phase transitions in matrix product systems  

E-Print Network (OSTI)

Recently, nonlocality and Bell inequalities have been used to investigate quantum phase transitions (QPTs) in low-dimensional quantum systems. Nonlocality can be detected by the Bell-CHSH function (BCF). In this work, we extend the study of BCF to the QPTs in matrix product systems (MPSs). In this kind of QPTs, the ground-state energy keeps analytical in the vicinity of the QPT points, and is usually called the MPS-QPTs. For several typical models, our results show that BCF can signal the MPS-QPTs very well. In addition, we find BCF can capture signal of QPTs in unentangled states and classical states, for which other measures of quantum correlation (quantum entanglement and quantum discord) fail. Furthermore, we find that in these MPSs, there exists some kind of quantum correlation which cannot be characterized by entanglement, or by nonlocality.

Zhao-Yu Sun; Hai-Lin Huang; Bo Wang

2013-04-13T23:59:59.000Z

240

STRATEGIC PLAN FOR COORDINATING RURAL INTELLIGENT TRANSPORTATION SYSTEM (ITS) TRANSIT DEVELOPMENT IN THE GREAT SMOKY MOUNTAINS NATIONAL PARK  

NLE Websites -- All DOE Office Websites (Extended Search)

256 256 STRATEGIC PLAN FOR COORDINATING RURAL INTELLIGENT TRANSPORTATION SYSTEM (ITS) TRANSIT DEVELOPMENT IN THE GREAT SMOKY MOUNTAINS NATIONAL PARK L. F. Truett (TRUETTLF@ORNL.GOV) S. M. Chin (CHINS@ORNL.GOV) E. C. P. Chang (ECC2005@ORNL.GOV) November 2002 Prepared for the FEDERAL TRANSIT ADMINISTRATION U.S. DEPARTMENT OF TRANSPORTATION Washington, D.C. 20590 Prepared by the Center for Transportation Analysis OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee 37831-6073 managed by UT-BATTELLE, LLC for the U.S. DEPARTMENT OF ENERGY under Contract No. DE-AC05-00OR22725 Coordination of Transit Concepts in GSMNP page iii, 11/12/02 STRATEGIC PLAN FOR COORDINATING RURAL INTELLIGENT TRANSPORTATION SYSTEM (ITS) TRANSIT DEVELOPMENT IN THE

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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241

Impact of the Variable Refrigerant Volume Air Conditioning System on Building Energy Efficiency  

E-Print Network (OSTI)

The application of the variable refrigerant volume multi-zone air conditioning systems has met with mixed results since the publication of the Design Standard for Energy Efficiency of Public Buildings. This paper analyzes the characteristics of the variable refrigerant volume multi-zone air conditioning system, and discusses the advantages of its application.

Zhu, H.

2006-01-01T23:59:59.000Z

242

Poster: INPRESS: indoor climate prediction and evaluation system for energy efficiency using sensor networks  

Science Conference Proceedings (OSTI)

Modern buildings include an indoor climate control system, installed and operated to maintain a comfortable environment for the building occupants. However, these climate control systems consume a significant amount of energy due to an inefficient control ... Keywords: energy efficiency, indoor climate, sensor network

Jae Yoon Chong; Jinwook Baek; Sukun Kim

2011-11-01T23:59:59.000Z

243

OBSERVE: Occupancy-Based System for Efficient Reduction of HVAC Energy  

E-Print Network (OSTI)

control conditioning strategies. Using strategies based on sensor network occupancy model predictions, weOBSERVE: Occupancy-Based System for Efficient Reduction of HVAC Energy Varick L. Erickson, Miguel Á Descriptors I.6.5 [Simulation and Modeling]: Model Development; J.7 [Computers In Other Systems]: Command

Cerpa, Alberto E.

244

TRANSPORTATION SYSTEMS are the build-ing blocks of modern society. Efficient and  

E-Print Network (OSTI)

TRANSPORTATION SYSTEMS are the build- ing blocks of modern society. Efficient and safe movement. How- ever, transportation systems by their very nature also affect the environment through operations, construction, and maintenance of transportation facilities, and through the travel behaviors they encourage

Wang, Yuhang

245

Decision system based on neural networks to optimize the energy efficiency of a petrochemical plant  

Science Conference Proceedings (OSTI)

The energy efficiency of industrial plants is an important issue in any type of business but particularly in the chemical industry. Not only is it important in order to reduce costs, but also it is necessary even more as a means of reducing the amount ... Keywords: Cost optimization, Crude oil distillation, Data mining, Decision system, Expert system, Neural network, Petrochemical plant

Iñigo Monedero; Félix Biscarri; Carlos León; Juan I. Guerrero; Rocio González; Luis Pérez-Lombard

2012-08-01T23:59:59.000Z

246

Purchasing a New Energy-Efficient Central Heating System | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System October 21, 2008 - 4:00am Addthis John Lippert Energy prices are skyrocketing. According to the Energy Information Administration's October 7, 2008 forecast, heating fuel expenditures for the average household using oil as its primary heating fuel are expected to increase by $449 over last winter. Households using natural gas to heat their homes can expect to pay $155 more this winter, on average, than last year, and those using propane can expect to pay $188 more. Households heating primarily with electricity can expect to pay an average of $89 more. That's a lot of money resulting solely from rising heating expenses. You may long for the "good old days," but when it comes to heating systems,

247

Purchasing a New Energy-Efficient Central Heating System | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System October 21, 2008 - 4:00am Addthis John Lippert Energy prices are skyrocketing. According to the Energy Information Administration's October 7, 2008 forecast, heating fuel expenditures for the average household using oil as its primary heating fuel are expected to increase by $449 over last winter. Households using natural gas to heat their homes can expect to pay $155 more this winter, on average, than last year, and those using propane can expect to pay $188 more. Households heating primarily with electricity can expect to pay an average of $89 more. That's a lot of money resulting solely from rising heating expenses. You may long for the "good old days," but when it comes to heating systems,

248

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

E-Print Network (OSTI)

Performance of ground source heat pump system in a near-zerosimulation tool for ground- source heat pump system designflow systems and ground source heat pump systems Abstract

Hong, Tainzhen

2010-01-01T23:59:59.000Z

249

Efficiency of energy transfer in a light-harvesting system under quantum coherence  

E-Print Network (OSTI)

We investigate the role of quantum coherence in the efficiency of excitation transfer in a ring-hub arrangement of interacting two-level systems, mimicking a light-harvesting antenna connected to a reaction center as it is found in natural photosynthetic systems. By using a quantum jump approach, we demonstrate that in the presence of quantum coherent energy transfer and energetic disorder, the efficiency of excitation transfer from the antenna to the reaction center depends intimately on the quantum superposition properties of the initial state. In particular, we find that efficiency is sensitive to symmetric and asymmetric superposition of states in the basis of localized excitations, indicating that initial state properties can be used as a efficiency control parameter at low temperatures.

Alexandra Olaya-Castro; Chiu Fan Lee; Francesca Fassioli Olsen; Neil F. Johnson

2007-08-08T23:59:59.000Z

250

SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Efficiency Thermal Energy Storage System for CSP High-Efficiency Thermal Energy Storage System for CSP ANL logo Photo of a black and white porous material magnified 50 times by a microscope. Microstructure of the highly thermal conductive foam that will be used for the prototype TES system. Image from ANL Argonne National Laboratory and project partner Ohio Aerospace Institute, under the National Laboratory R&D competitive funding opportunity, will design, develop, and test a prototype high-temperature and high-efficiency thermal energy storage (TES) system with rapid charging and discharging times. By increasing the efficiency of TES systems, this project aims to lower the capital costs of concentrating solar power (CSP) systems. Approach The research team is developing and evaluating a novel approach for TES at temperatures greater than 700˚C for CSP systems. The approach uses high thermal conductivity and high-porosity graphite foams infiltrated with a phase change material (PCM) to provide TES in the form of latent heat.

251

Improving the efficiency of residential air-distribution systems in California, Phase 1  

Science Conference Proceedings (OSTI)

This report describes the results of the first phase of a multiyear research project. The project`s goal is to investigate ways to improve the efficiency of air-distribution systems in detached, single-family residences in California. First-year efforts included: A survey of heating, ventilating, and air conditioning (HVAC) contractors in California. A 31-house field study of distribution-system performance based on diagnostic measurements. Development of an integrated air-flow and thermal-simulation tool for investigating residential air-distribution system performance. Highlights of the field results include the following: Building envelopes for houses built after 1979 appear to be approximately 30% tighter. Duct-system tightness showed no apparent improvement in post-1979 houses. Distribution-fan operation added an average of 0.45 air changes per hour (ACH) to the average measured rate of 0.24 ACH. The simulation tool developed is based on DOE-2 for the thermal simulations and on MOVECOMP, an air-flow network simulation model, for the duct/house leakage and flow interactions. The first complete set of simulations performed (for a ranch house in Sacramento) indicated that the overall heating-season efficiency of the duct systems was approximately 65% to 70% and that the overall cooling-season efficiency was between 60% and 75%. The wide range in cooling-season efficiency reflects the difference between systems with attic return ducts and those with crawl-space return ducts, the former being less efficient. The simulations also indicated that the building envelope`s UA-value, a measurement of thermoconductivity, did not have a significant impact on the overall efficiency of the air-distribution system.

Modera, M.; Dickerhoff, D.; Jansky, R.; Smith, B.

1992-06-01T23:59:59.000Z

252

Sensitivity of forced air distribution system efficiency to climate, duct location, air leakage and insulation  

Science Conference Proceedings (OSTI)

This study was performed in order to find suitable efficiency and leakage specifications for Energy Star duct systems and provide recommendations on duct insulation specifications. This analysis looks at a typical house, with a selection of duct locations, climates, duct insulation (R-value), and duct leakage. A set of calculations were performed with reduced capacity and airflow to look at the effect of variable capacity systems. This was done to address concerns regarding the increased efficiency of multi-capacity equipment due to good part load performance and how these efficiency gains may be offset by increased duct losses. The duct system efficiencies were calculated using the procedures in proposed ASHRAE Standard 152P ''Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems'' (ASHRAE 1999). This proposed ASHRAE Standard can be used to calculate duct efficiency for both design and seasonal weather conditions. In this report, the seasonal efficiencies are used for most of the analysis because they are the most appropriate for estimating energy consumption in buildings. The effects at peak conditions are examined for changing duct insulation in order to provide preliminary estimates of the potential responses to time of use pricing. The study was performed in two parts. The first part focused on duct leakage and the second part on duct insulation. The HVAC systems in the two parts share many attributes, however, they differ in detail and so are treated separately here. All the calculation results are summarized in tables in the Appendix, and specific results are given in the text.

Walker, Iain

2001-09-01T23:59:59.000Z

253

Optimizing the Power Delivery Network in Dynamically Voltage Scaled Systems with Uncertain Power Mode Transition Times  

E-Print Network (OSTI)

, where state transition rates are controlled by actions a A. We consider a cost function which assigns matrix G is defined as an nÃ?n matrix, where an entry s,s' in G is called the transition rate from state s to another state s'. The transition rates may be calculated as follows, , ' '( ) ( ', ) (1/ ( , ')),s

Pedram, Massoud

254

Energy efficient Phase Change Memory based main memory for future high performance systems  

Science Conference Proceedings (OSTI)

Phase Change Memory (PCM) has recently attracted a lot of attention as a scalable alternative to DRAM for main memory systems. As the need for high-density memory increases, DRAM has proven to be less attractive from the point of view of scaling and ... Keywords: DDR3 commodity DRAM memory system, energy efficient phase change memory, main memory, future high performance systems, energy consumption, latency issues, write energy, write endurance, cache, embedded DRAM

R. A. Bheda; Jason A. Poovey; J. G. Beu; T. M. Conte

2011-07-01T23:59:59.000Z

255

A PARALLAX DISTANCE AND MASS ESTIMATE FOR THE TRANSITIONAL MILLISECOND PULSAR SYSTEM J1023+0038  

Science Conference Proceedings (OSTI)

The recently discovered transitional millisecond pulsar system J1023+0038 exposes a crucial evolutionary phase of recycled neutron stars for multiwavelength study. The system, comprising the neutron star itself, its stellar companion, and the surrounding medium, is visible across the electromagnetic spectrum from the radio to X-ray/gamma-ray regimes and offers insight into the recycling phase of millisecond pulsar evolution. Here, we report on multiple-epoch astrometric observations with the Very Long Baseline Array (VLBA) which give a system parallax of 0.731 {+-} 0.022 milliarcseconds (mas) and a proper motion of 17.98 {+-} 0.05 mas yr{sup -1}. By combining our results with previous optical observations, we are able to use the parallax distance of 1368{sup +42}{sub -{sub 39}} pc to estimate the mass of the pulsar to be 1.71 {+-} 0.16 M{sub Sun }, and we are also able to measure the three-dimensional space velocity of the system to be 126 {+-} 5 km s{sup -1}. Despite the precise nature of the VLBA measurements, the remaining {approx}3% distance uncertainty dominates the 0.16 M{sub Sun} error on our mass estimate.

Deller, A. T. [Netherlands Institute for Radio Astronomy (ASTRON), 7990-AA Dwingeloo (Netherlands); Archibald, A. M.; Kaspi, V. M. [Department of Physics, McGill University, 3600 University Street, Montreal, QC H3A 2T8 (Canada); Brisken, W. F. [National Radio Astronomy Observatory, Socorro, NM 87801 (United States); Chatterjee, S. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Janssen, G. H.; Lyne, A. G.; Stappers, B. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Lorimer, D.; McLaughlin, M. A. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Ransom, S. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Stairs, I. H. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)

2012-09-10T23:59:59.000Z

256

On the Contribution of Compressed Air Systems to Energy Efficiency Targets  

NLE Websites -- All DOE Office Websites (Extended Search)

On the Contribution of Compressed Air Systems to Energy Efficiency Targets On the Contribution of Compressed Air Systems to Energy Efficiency Targets - A Function-Based Bottom-Up Approach Speaker(s): Patrick Plötz Date: May 4, 2012 - 2:00pm Location: 90-4133 Seminar Host/Point of Contact: Sanaee Iyama Achieving current EU energy targets as stipulated in the energy service directive and in the energy strategy for 2020 implies substantial efficiency improvements across a variety of industrial end-uses. The achievable saving potential of an end-use depends considerably on the age structure of the existing stock and on the technology definition, i.e. whether a product approach, an extended product approach or a system-approach is used. Within this context, important ErP studies on air compressors are in preparation. In this paper, we address the possible

257

Energy Efficiency Evaluation of Refrigeration Technologies in Combined Cooling, Heating and Power Systems  

E-Print Network (OSTI)

With development of absorption refrigeration technology, the cooling requirement can be met using various optional refrigeration technologies in a CCHP system, including compression refrigeration, steam double-effect absorption refrigeration, steam single-effect absorption refrigeration, flue gas absorption refrigeration and hot water absorption refrigeration, etc. As a universal criterion, the COP coefficient cannot reflect the difference in availability of driving energy for different chillers. Exergy efficiency of optional chillers in CCHP system was analyzed and compared, which can be regarded as an important reference criterion in comparison of energy efficiency. Furthermore, a new index, relative electricity saving ratio, was put forward for evaluating end energy efficiency of all kinds of chillers in a CCHP system, which indicates actual energy or electricity saving ratio for different absorption chillers with various parameters in contrast to the reference electricity-driven refrigeration scheme.

Zuo, Z.; Hu, W.

2006-01-01T23:59:59.000Z

258

Macro-modeling and energy efficiency studies of file management in embedded systems with flash memory  

E-Print Network (OSTI)

Technological advancements in computer hardware and software have made embedded systems highly affordable and widely used. Consumers have ever increasing demands for powerful embedded devices such as cell phones, PDAs and media players. Such complex and feature-rich embedded devices are strictly limited by their battery life- time. Embedded systems typically are diskless and use flash for secondary storage due to their low power, persistent storage and small form factor needs. The energy efficiency of a processor and flash in an embedded system heavily depends on the choice of file system in use. To address this problem, it is necessary to provide sys- tem developers with energy profiles of file system activities and energy efficient file systems. In the first part of the thesis, a macro-model for the CRAMFS file system is established which characterizes the processor and flash energy consumption due to file system calls. This macro-model allows a system developer to estimate the energy consumed by CRAMFS without using an actual power setup. The second part of the thesis examines the effects of using non-volatile memory as a write-behind buffer to improve the energy efficiency of JFFS2. Experimental results show that a 4KB write-behind buffer significantly reduces energy consumption by up to 2-3 times for consecutive small writes. In addition, the write-behind buffer conserves flash space since transient data may never be written to flash.

Goyal, Nitesh

2005-05-01T23:59:59.000Z

259

Energy Savings with Energy-Efficient HVAC Systems in Commercial Buildings of Hong Kong  

E-Print Network (OSTI)

Hong Kong has seen a dramatic increase in energy consumption in recent years, particularly electricity use in commercial buildings. The growth of electricity demand in future years is crucial both economically and environmentally. As over half of the electricity in Hong Kong is consumed by commercial buildings, and heating, ventilation and air-conditioning (HVAC) is the largest end-user in such buildings, improving the efficiency of HVAC systems in commercial buildings, is the key measure to take in Hong Kong for sustainable development. In this study, the major factors influencing the electricity use of HVAC systems are studied with the building energy simulation program EnergyPlus, which include chiller efficiency, space cooling temperature, variable vs. constant air flow, fan efficiency, lighting intensity and building envelope. From the analysis of the simulation results, it can be found that substantial energy-saving potential exists through improving the efficiency of HVAC systems in commercial buildings, and a combination of desirable system parameters for energy efficiency of commercial building is proposed.

Yang, J.; Chan, K.; Wu, X.

2006-01-01T23:59:59.000Z

260

Free-energy functional for freezing transitions: Hard sphere systems freezing into crystalline and amorphous structures  

E-Print Network (OSTI)

A free-energy functional that contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the freezing of a system of hard spheres into crystalline and amorphous structures. The freezing parameters for fluid-crystal transition have been found to be in very good agreement with the results found from simulations. We considered amorphous structures found from the molecular dynamics simulations at packing fractions $\\eta$ lower than the glass close packing fraction $\\eta_{J}$ and investigated their stability compared to that of a homogeneous fluid. The existence of free-energy minimum corresponding to a density distribution of overlapping Gaussians centered around an amorphous lattice depicts the deeply supercooled state with a heterogeneous density profile.

Swarn Lata Singh; Atul S. Bharadwaj; Yashwant Singh

2011-01-31T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Direct probe of Mott-Hubbard to charge-transfer insulator transition and electronic structure evolution in transition-metal systems  

DOE Green Energy (OSTI)

We report the most direct experimental verification of Mott-Hubbard and charge-transfer insulators through x-ray emission spectroscopy in transition-metal (TM) fluorides. The p-d hybridization features in the spectra allow a straightforward energy alignment of the anion-2p and metal-3d valence states, which visually shows the difference between the two types of insulators. Furthermore, in parallel with the theoretical Zaanen-Sawatzky-Allen diagram, a complete experimental systematics of the 3d Coulomb interaction and the 2p-3d charge-transfer energy is reported and could serve as a universal experimental trend for other TM systems including oxides.

Olalde-Velasco, P; Jimenez-Mier, J; Denlinger, JD; Hussain, Z; Yang, WL

2011-07-11T23:59:59.000Z

262

Energy Efficiency Challenges in Heating Supply System of Turkmenistan and Potential Solutions  

E-Print Network (OSTI)

The poor condition and inefficient operation of the existing heat and hot water supply system in Turkmenistan is causing serious economic, social and environmental problems. Yet, the situation may very well change to the worse as increase of energy consumption is projected for near future. The country's commitment to reduce greenhouse gases emissions faces the challenge of ensuring that both the short- and long-term environmental impacts can be minimized while service levels of heat and hot water supply to the population are simultaneously improved. Despite the energy, economic, and environmental benefits of energy efficiency in Turkmenistan, little has been done to eliminate energy waste. Due historic legacy, there is a limited institutional capacity to increase energy efficiency. Achieving energy and environmental goals will require a basic institutional transformation. Gaps in polices and legislation in the area of energy efficiency and the lack capacity and institutional expertise in managing local, regional and national energy efficiency programs have to be addressed.

Zomov, A.; Behnke, R.

2010-01-01T23:59:59.000Z

263

Improving Energy Efficiency of Compressed Air System Based on System Audit  

E-Print Network (OSTI)

can cover the maximum system demand. The similar successfulsized to meet the maximum plant air demand. Few air systems

Shanghai, Hongbo Qin; McKane, Aimee

2008-01-01T23:59:59.000Z

264

Human Capacity Building in Energy Efficiency and Renewable Energy System Maintenance for the Yurok Tribe  

DOE Green Energy (OSTI)

From July 2005 to July 2007, the Schatz Energy Research Center (SERC) assisted the Yurok Tribe in the implementation of a program designed to build the Tribe’s own capacity to improve energy efficiency and maintain and repair renewable energy systems in Tribal homes on the Yurok Reservation. Funding for this effort was provided by the U.S. Department of Energy’s Tribal Program under First Steps grant award #DE-FG36-05GO15166. The program’s centerpiece was a house-by-house needs assessment, in which Tribal staff visited and conducted energy audits at over fifty homes. The visits included assessment of household energy efficiency and condition of existing renewable energy systems. Staff also provided energy education to residents, evaluated potential sites for new household renewable energy systems, and performed minor repairs as needed on renewable energy systems.

Engel, R. A.' Zoellick, J J.

2007-07-31T23:59:59.000Z

265

High Temperature Superconducting Magnets for Efficient Low Energy Beam Transport Systems  

E-Print Network (OSTI)

Modern ion accelerators and ion implantation systems need very short, highly versatile, Low Energy Beam Transport (LEBT) systems. The need for reliable and continuous operation requires LEBT designs to be simple and robust. The energy efficiency of available high temperature superconductors (HTS), with efficient and simple cryocooler refrigeration, is an additional attraction. Innovative, compact LEBT systems based on solenoids designed and built with high-temperature superconductor will be developed using computer models and prototyped. The parameters will be chosen to make this type of LEBT useful in a variety of ion accelerators, ion implantation systems, cancer therapy synchrotrons, and research accelerators, including the ORNL SNS. The benefits of solenoids made with HTS will be evaluated with analytical and numerical calculations for a two-solenoid configuration, as will be used in the SNS prototype LEBT that will replace the electrostatic one at SNS, and a single solenoid configuration, as was proposed...

Popovic, M; Johnson, R P; Nipper, J H

2013-01-01T23:59:59.000Z

266

Energy Efficient Single Stack Exhaust Fan Systems (E3S3F)  

E-Print Network (OSTI)

This paper first investigates the fan energy performance of a constant air volume exhaust system. Two single stack energy efficient exhaust fan systems (E3S3F) are presented. The E3S3F-I has the static pressure sensor located at the inlet of the exhaust fan. It has been found to consume up to 15% less fan power than conventional constant air volume exhaust systems. The E3S3F-II uses a variable speed device to maintain the static pressure at the entrance of the stack. It consumes up to 60% less fan power than conventional constant volume exhaust systems.

Wang, G.; Liu, M.

2001-01-01T23:59:59.000Z

267

Energy Storage: Materials, Systems and Applications  

Science Conference Proceedings (OSTI)

Mar 29, 2011 ... The transition from the fossil economy to a greener, sustainable economy cannot, however, be realized without efficient energy storage systems ...

268

E2WFQ: an energy efficient fair scheduling policy for wireless systems  

Science Conference Proceedings (OSTI)

As embedded systems are being networked, often wirelessly, an increasingly larger share of their total energy budget is due to the communication. This necessitates the development of power management techniques that address communication subsystems, ... Keywords: energy efficient design, fair scheduling, power management, wireless communications

Vijay Raghunathan; Saurabh Ganeriwal; Curt Schurgers; Mani Srivastava

2002-08-01T23:59:59.000Z

269

Computationally efficient algorithms for location area planning in future cellular systems  

Science Conference Proceedings (OSTI)

Efficient resource utilisation in future cellular systems is related to the control of the signalling load imposed by the location update and paging operations. Important means for controlling this load is the ''proper'' planning of location areas. In ... Keywords: Genetic algorithm paradigm, Simulated annealing, Taboo search

P. Demestichas; N. Georgantas; E. Tzifa; V. Demesticha; M. Striki; M. Kilanioti; M. Theologou

2000-07-01T23:59:59.000Z

270

Designing Energy Efficient Communication Runtime Systems for Data Centric Programming Models  

Science Conference Proceedings (OSTI)

The insatiable demand of high performance computing is being driven by the most computationally intensive applications such as computational chemistry, climate modeling, nuclear physics, etc. The last couple of decades have observed a tremendous rise ... Keywords: PGAS, Communication Runtime Systems, Energy Efficiency

Abhinav Vishnu; Shuaiwen Song; Andres Marquez; Kevin Barker; Darren Kerbyson; Kirk Cameron; Pavan Balaji

2010-12-01T23:59:59.000Z

271

Charge Migration Efficiency Optimization in Hybrid Electrical Energy Storage (HEES) Systems  

E-Print Network (OSTI)

. Experimental results for an HEES system comprising of banks of batteries and supercapacitors demonstrate a migration efficiency improvement up to 51.3%, for su- percapacitor to battery and supercapacitor to supercapacitor charge migration. 1. INTRODUCTION Electrical energy usage changes over time due to the types

Pedram, Massoud

272

Proceedings of the Fourth ACM Workshop on Embedded Sensing Systems for Energy-Efficiency in Buildings  

Science Conference Proceedings (OSTI)

On behalf of the Technical Program Committee (TPC), it is our great pleasure to welcome you to the 2012 ACM Workshop on Embedded Systems for Energy Efficiency in Buildings (BuildSys), in Toronto, Canada. We have what we believe is an exceptional technical ...

George J. Pappas

2012-11-01T23:59:59.000Z

273

Designing energy efficient communication runtime systems: a view from PGAS models  

Science Conference Proceedings (OSTI)

As the march to the exascale computing gains momentum, energy consumption of supercomputers has emerged to be the critical roadblock. While architectural innovations are imperative in achieving computing of this scale, it is largely dependent on the ... Keywords: Communication runtime system, DVFS, Energy efficiency, InfiniBand

Abhinav Vishnu; Shuaiwen Song; Andres Marquez; Kevin Barker; Darren Kerbyson; Kirk Cameron; Pavan Balaji

2013-03-01T23:59:59.000Z

274

Absorber and emitter for solar thermo-photovoltaic systems to achieve efficiency  

E-Print Network (OSTI)

Pbs photovoltaic cells," Int. J. Energy Res. 16(6), 481­487 (1992). 7. V. Badescu, "ThermodynamicAbsorber and emitter for solar thermo- photovoltaic systems to achieve efficiency exceeding, provides a sharp emissivity peak at the solar cell band-gap while suppressing emission at lower frequencies

Fan, Shanhui

275

Towards an empirical method of efficiency testing of system parts: A methodological study  

Science Conference Proceedings (OSTI)

Current usability evaluation methods are essentially holistic in nature. However, engineers that apply a component-based software engineering approach might also be interested in understanding the usability of individual parts of an interactive system. ... Keywords: Efficiency, Empirical method, HCI methodology, Log file analysis, Usability evaluation method, Usability testing

Willem-Paul Brinkman; Reinder Haakma; Don G. Bouwhuis

2007-05-01T23:59:59.000Z

276

Designing cost-efficient wireless sensor/actuator networks for building control systems  

Science Conference Proceedings (OSTI)

A modern Building Automation System (BAS) aims to enhance the functionality of interactive control strategies leading towards energy efficiency and enhanced user comfort. Typically, it is cheaper to embed the BAS within a Wireless Sensor/Actuator Network ... Keywords: MPC, building energy, co-design, sensor

Alie El-Din Mady; Gregory Provan; Ning Wei

2012-11-01T23:59:59.000Z

277

Transition to Turbulence and Effect of Initial Conditions on 3D Compressible Mixing in Planar Blast-wave-driven Systems  

Science Conference Proceedings (OSTI)

Perturbations on an interface driven by a strong blast wave grow in time due to a combination of Rayleigh-Taylor, Richtmyer-Meshkov, and decompression effects. In this paper, results from three-dimensional numerical simulations of such a system under drive conditions to be attainable on the National Ignition Facility [E. M. Campbell, Laser Part. Beams, 9(2), 209 (1991)] are presented. Using the multi-physics, adaptive mesh refinement, higher order Godunov Eulerian hydrocode, Raptor [L. H. Howell and J.A. Greenough, J. Comp. Phys. 184, 53 (2003)], the late nonlinear instability evolution, including transition to turbulence, is considered for various multimode perturbation spectra. The 3D post-transition state differs from the 2D result, but the process of transition proceeds similarly in both 2D and 3D. The turbulent mixing transition results in a reduction in the growth rate of the mixing layer relative to its pre-transition value and, in the case of the bubble front, relative to the 2D result. The post-transition spike front velocity is approximately the same in 2D and 3D. Implications for hydrodynamic mixing in core-collapse supernova are discussed.

Miles, A R; Edwards, M J; Greenough, J A

2004-11-08T23:59:59.000Z

278

Test and Evaluation of a High Efficiency Residential Fuel Cell System  

Science Conference Proceedings (OSTI)

A confluence of industry drivers, including the availability of low-cost natural gas, is creating new market opportunities for natural gas-based distributed generation. Solid oxide fuel cell systems (SOFC) are a potentially attractive option because of their high electrical efficiency (50–60% lower heating value (LHV)). This report documents two years of testing and evaluation of a 1.5 kW SOFC residential system provided by Ceramics Fuel Cell Limited. Tests were conducted in collaboration with ...

2013-12-20T23:59:59.000Z

279

Tradeoffs between Costs and Greenhouse Gas Emissions in the Design of Urban Transit Systems.  

E-Print Network (OSTI)

??Public transit is often touted as a "green" transportation option and a way for users to reduce their environmental footprint by avoiding automobile emissions. Many… (more)

Griswold, Julia Baird

2013-01-01T23:59:59.000Z

280

Improving Energy Efficiency of Compressed Air System Based on System Audit  

E-Print Network (OSTI)

50 compressed air system energy audits completed by Shanghai50 compressed air system energy audits completed by Shanghaiof compressed air energy audits conducted by the Shanghai

Shanghai, Hongbo Qin; McKane, Aimee

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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281

Maximal spin and energy conversion efficiency in a symbiotic system of black hole, disk and jet  

E-Print Network (OSTI)

We study the mass and spin evolution in a symbiotic system consisting of a black hole with magnetosphere and jets, surrounded by a steady-state, thin accretion disk. We analyze how the limiting value of the spin parameter and the conversion efficiency of accreted mass into radiation depend on the interplay of electromagnetic radiation reaction, magnetosphere characteristics and jet cross-section. As a main result, we find that the presence of the jets increases the spin limit (basically obstructing the reverse effect of radiation in the innermost region of the accretion disk) and enhances the energy conversion efficiency.

Kovács, Zoltán; Biermann, Peter L

2010-01-01T23:59:59.000Z

282

Hybrid energy storage systems based on compressed air and supercapacitors with maximum efficiency point tracking  

E-Print Network (OSTI)

This paper presents a hybrid energy storage system based on Compressed Air Energy Storage (CAES), where the charging and discharging is done within maximum efficiency conditions. As the maximum efficiency conditions impose the level of converted power, an intermittent time-modulated operation mode is applied to the thermodynamic converter to obtain a variable converted power. A smoothly variable output power is achieved with the help of a supercapacitive auxiliary storage device used as a filter. The paper describes the concept of the system, the power-electronic interface circuits and especially the Maximum Efficiency Point Tracking (MEPT) algorithm and the strategy used to vary the output power. In addition, the paper will present the characteristics of a high efficiency storage device where the pure pneumatic machine is replaced by an oil-hydraulics and pneumatics converter, used under isothermal conditions. Practical results are also presented, recorded from a low-power pneumatic motor coupled to a small DC generator, as well as from a first prototype of the final hydraulic/pneumatic system.

Sylvain Lemofouet; Alfred Rufer

2005-01-01T23:59:59.000Z

283

Improving Energy Efficiency in Pharmaceutical ManufacturingOperations -- Part I: Motors, Drives and Compressed Air Systems  

Science Conference Proceedings (OSTI)

In Part I of this two-part series, we focus on efficient use of motors, drives and pumps, both for process equipment and compressed air systems. Pharmaceutical manufacturing plants in the U.S. spend nearly $1 billion each year for the fuel and electricity they need to keep their facilities running (Figure 1, below). That total that can increase dramatically when fuel supplies tighten and oil prices rise, as they did last year. Improving energy efficiency should be a strategic goal for any plant manager or manufacturing professional working in the drug industry today. Not only can energy efficiency reduce overall manufacturing costs, it usually reduces environmental emissions, establishing a strong foundation for a corporate greenhouse-gas-management program. For most pharmaceutical manufacturing plants, Heating, Ventilation and Air Conditioning (HVAC) is typically the largest consumer of energy, as shown in Table 1 below. This two-part series will examine energy use within pharmaceutical facilities, summarize best practices and examine potential savings and return on investment. In this first article, we will focus on efficient use of motors, drives and pumps, both for process equipment and compressed air systems. Part 2, to be published in May, will focus on overall HVAC systems, building management and boilers.

Galitsky, Christina; Chang, Sheng-chien; Worrell, Ernst; Masanet,Eric

2006-04-01T23:59:59.000Z

284

Highly-efficient noise-assisted energy transport in classical oscillator systems  

E-Print Network (OSTI)

Photosynthesis is a biological process that involves the highly-efficient transport of energy captured from the sun to a reaction center, where conversion into useful biochemical energy takes place. Even though one can always use a quantum perspective to describe any physical process, since everything follows the laws of Quantum Mechanics, is the use of quantum theory imperative to explain this high efficiency? Making use of the quantum-classical correspondence of electronic energy transfer recently introduced by Eisfeld and Briggs [Phys. Rev. E 85, 046118 (2012)], we show here that the highly-efficient noise-assisted energy transport described by Rebentrost et al. [New J. Phys. 11, 033003 (2009)], and Plenio and Huelga [New J. Phys. 10, 113019 (2008)], as the result of the interplay between the quantum coherent evolution of the photosynthetic system and noise introduced by its surrounding environment, it can be found as well in purely classical systems. The wider scope of applicability of the enhancement of energy transfer assisted by noise might open new ways for developing new technologies aimed at enhancing the efficiency of a myriad of energy transfer systems, from information channels in micro-electronic circuits to long-distance high-voltage electrical lines.

R. de J. León-Montiel; Juan P. Torres

2013-01-08T23:59:59.000Z

285

Efficient Motor System Tools Sponsored by the DOE Motor Challenge Program  

E-Print Network (OSTI)

The Department of Energy's (DOE) Motor Challenge program is an industry/government collaborative that is working to increase the market penetration of efficient motor-driven systems. In support of the program's Showcase Demonstrations, a variety of tools, protocols and databases are being developed. These tools will aid industry in the design, implementation, procurement, and validation of the benefits of energy efficient motor-driven systems. DOE's goal is to provide value-added products to industry to facilitate the decision-making process in maintaining and upgrading motor-driven systems and components. Tools will focus not only on energy factors, but also on productivity, reliability, and capital cost reduction. The tools will be flexible enough to be useful and user-friendly to all potential industrial end-users. It is important that the tools complement rather than compete with currently available software products. To facilitate concurrent development and future improvements, the software tools will consist of modular components.

Blazewicz, S.; McCoy, G. A.; Olszewski, M.; Scheihing, P.

1995-04-01T23:59:59.000Z

286

HIGH EFFICIENCY, LOW EMISSIONS, SOLID OXIDE FUEL CELL SYSTEMS FOR MULTIPLE APPLICATIONS  

DOE Green Energy (OSTI)

Technology Management Inc. (TMI), teamed with the Ohio Office of Energy Efficiency and Renewable Energy, has engineered, constructed, and demonstrated a stationary, low power, multi-module solid oxide fuel cell (SOFC) prototype system operating on propane and natural gas. Under Phase I, TMI successfully operated two systems in parallel, in conjunction with a single DC-AC inverter and battery bus, and produced net AC electricity. Phase II testing expanded to include alternative and renewable fuels typically available in rural regions of Ohio. The commercial system is expected to have ultra-low pollution, high efficiency, and low noise. The TMI SOFC uses a solid ceramic electrolyte operating at high temperature (800-1000 C) which electrochemically converts gaseous fuels (hydrogen or mixed gases) and oxygen into electricity. The TMI system design oxidizes fuel primarily via electrochemical reactions and uses no burners (which pollute and consume fuel)--resulting in extremely clean exhaust. The use of proprietary sulfur tolerant materials developed by TMI allows system operation without additional fuel pre-processing or sulfur removal. Further, the combination of high operating temperatures and solid state operation increases the potential for higher reliability and efficiencies compared to other types of fuel cells. Applications for the TMI SOFC system cover a wide range of transportation, building, industrial, and military market sectors. A generic technology, fuel cells have the potential to be embodied into multiple products specific to Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) program areas including: Fuel Cells and Microturbines, School Buildings, Transportation, and Bioenergy. This program focused on low power stationary applications using a multi-module system operating on a range of common fuels. By producing clean electricity more efficiently (thus using less fuel), fuel cells have the triple effect of cleaning up the environment, reducing the amount of fuel consumed and, for energy intensive manufacturers, boosting their profits (by reducing energy expenses). Compared to conventional power generation technologies such as internal combustion engines, gas turbines, and coal plants, fuel cells are extremely clean and more efficient, particularly at smaller scales.

Sara Ward; Michael A. Petrik

2004-07-28T23:59:59.000Z

287

Work plan for transition of SY-101 hydrogen mitigation test project data acquisition and control system (DACS-1)  

DOE Green Energy (OSTI)

The purpose of this effort is to transfer operating and maintenance responsibility for the 241-SY-101 data acquisition and control system (DACS-1) from Los Alamos National Laboratory to Westinghouse Hanford Company. This work plan defines the tasks required for a successful turnover. It identifies DACS-1 transition, deliverables, responsible organizations and individuals, interfaces, cost, and schedule. The transition plan will discuss all required hardware, software, documentation, maintenance, operations, and training for use at Hanford Waste Tank 241-SY-101. The transfer of responsibilities for DACS-1 to WHC is contingent on final approval of applicable Acceptance for Beneficial Use documentation by Waste Tank Operations. The DACS-1 was designed to provide data monitoring, display, and storage for Tank 241-SY-101. The DACS-1 also provides alarm and control of all the hydrogen mitigation testing systems, as well as ancillary systems and equipment (HVAC, UPS, etc.) required to achieve safe and reliable operation of the testing systems in the tank.

McClees, J.; Truitt, R.W.

1994-10-12T23:59:59.000Z

288

Advanced Systems of Efficient Use of Electrical Energy SURE (Smart Grid  

Open Energy Info (EERE)

Efficient Use of Electrical Energy SURE (Smart Grid Efficient Use of Electrical Energy SURE (Smart Grid Project) Jump to: navigation, search Project Name Advanced Systems of Efficient Use of Electrical Energy SURE Country Slovenia Coordinates 46.151241°, 14.995463° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":46.151241,"lon":14.995463,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

289

Energy Efficiency: The New Holy Grail of Data Management Systems Research  

E-Print Network (OSTI)

Energy costs are quickly rising in large-scale data centers and are soon projected to overtake the cost of hardware. As a result, data center operators have recently started turning into using more energy-friendly hardware. Despite the growing body of research in power management techniques, there has been little work to date on energy efficiency from a data management software perspective. In this paper, we argue that hardware-only approaches are only part of the solution, and that data management software will be key in optimizing for energy efficiency. We discuss the problems arising from growing energy use in data centers and the trends that point to an increasing set of opportunities for software-level optimizations. Using two simple experiments, we illustrate the potential of such optimizations, and, motivated by these examples, we discuss general approaches for reducing energy waste. Lastly, we point out existing places within database systems that are promising for energy-efficiency optimizations and ...

Harizopoulos, Stavros; Meza, Justin; Ranganathan, Parthasarathy

2009-01-01T23:59:59.000Z

290

IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 25, NO. 4, NOVEMBER 2010 1865 Impact of Energy Efficiency Incentives  

E-Print Network (OSTI)

IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 25, NO. 4, NOVEMBER 2010 1865 Impact of Energy Efficiency the implementation of energy efficiency poli- cies on the power distribution sector. To assess the outcome different energy efficiency levels required by the regulator. The results reveal that the introduction

Rudnick, Hugh

291

``You need this done by when?``: Increasing your efficiency with the SAS{reg_sign} system  

SciTech Connect

The SAS Institute publication -- SAS Programming Tips: A Guide to Efficient SAS Processing defines efficiency as ``obtaining more results from fewer computer or human resources.`` While this publication contains many very useful tips, it seems to concentrate mostly on computer efficiency. This paper will focus on ways of increasing your efficiency in developing, writing, and debugging SAS programs, i.e. increasing human efficiency. In my job as a consulting statistician, my programs are usually one-run programs. That is, I develop and test a program, then I run them once to get the results I need, and the program is typically never used again. Even for multiple run jobs, the greatest expense by far is the time used to develop a program, and any CPU/hardware ``expense`` is relatively insignificant. I believe that this is true for most SAS system users and that not enough attention has been given to this aspect of ``cost``. While most of these tips and techniques were developed under the PC platform, nearly all are applicable and useful under all SAS supported platforms. Some of the tips the experienced SAS programmer may already be familiar with, but many should be new and useful to both novice and veteran users.

DeHaan, M.S.

1992-08-01T23:59:59.000Z

292

Single Particle Jumps in a Binary Lennard-Jones System Below The Glass Transition  

E-Print Network (OSTI)

We study a binary Lennard-Jones system below the glass transition with molecular dynamics simulations. To investigate the dynamics we focus on events ("jumps") where a particle escapes the cage formed by its neighbors. Using single particle trajectories we define a jump by comparing for each particle its fluctuations with its changes in average position. We find two kinds of jumps: "reversible jumps," where a particle jumps back and forth between two or more average positions, and "irreversible jumps," where a particle does not return to any of its former average positions. For all investigated temperatures both kinds of particles jump and both irreversible and reversible jumps occur. With increasing temperature relaxation is enhanced by an increasing number of jumps, and growing jump lengths in position and potential energy. However, the waiting time between two successive jumps is independent of temperature. This temperature independence might be due to aging, which is present in our system. The ratio of irreversible to reversible jumps is also increasing with increasing temperature, which we interpret as a consequence of the increased likelihood of changes in the cages, i.e. a blocking of the "entrance" back into the previous cage. A comparison of the fluctuations of jumping particles and non-jumping particles indicates that jumping particles are more mobile even when not jumping. The jumps in energy normalized by their fluctuations are decreasing with increasing temperature, which is consistent with relaxation being increasingly driven by thermal fluctuations. In accordance with subdiffusive behavior are the distributions of waiting times and jump lengths in position.

K. Vollmayr-Lee

2003-08-28T23:59:59.000Z

293

Essays on Efficiency of the Farm Credit System and Dynamic Correlations in Fossil Fuel Markets  

E-Print Network (OSTI)

Markets have always changed in response to either exogenous or endogenous shocks. Many large events have occurred in financial and energy markets the last ten years. This dissertation examines market behavior and volatility in agricultural credit and fossil fuel markets under exogenous and endogenous changes in the last ten years. The efficiency of elements within the United States Farm Credit System, a major agricultural lender in the United States, and the dynamic correlation between coal, oil and natural gas prices, the three major fossil fuels, are examined. The Farm Credit system is a key lender in the U.S. agricultural sector, and its performance can influence the performance of the agricultural sector. However, its efficiency in providing credit to the agricultural sector has not been recently examined. The first essay of the dissertation provides assessments on the performance of elements within the Farm Credit System by measuring their relative efficiency using a stochastic frontier model. The second essay addresses the changes in relationship in coal, oil, and natural gas markets with respect to changes and turbulence in the last decade, which has also not been fully addressed in literature. The updated assessment on the relative performance of entities within the Farm Credit System provides information that the Farm Credit Administration and U.S. policy makers can use in their management of and policy toward the Farm Credit System. The measurement of the changes in fossil fuel markets’ relationships provides implications for energy investment, energy portfolio anagement, energy risk management, and energy security. It can also be used as a foundation for structuring forecasting models and other models related to energy markets. The dynamic correlations between coal, oil, and natural gas prices are examined using a dynamic conditional correlation multivariate autoregressive conditional heteroskedasticity (MGARCH DCC) model. The estimated results show that the FCS’s five banks and associations with large assets have more efficiently produced credit to the U.S. agricultural sector than smaller sized associations. Management compensation is found to be positively associated with the system’s efficiency. More capital investment and monitoring along with possible consolidation are implied for smaller sized associations to enhance efficiency. On average, the results show that the efficiency of the associations is increasing over time while the average efficiency of the five large banks is more stable. Overall, the associations exhibit a higher variation of efficiency than the five banks. In terms of energy markets the estimates from the MGARCH DCC model indicate significant and changing dynamic correlations and related volatility between the coal, oil, and natural gas prices. The coal price was found to experience more volatility and become more closely related to oil and natural gas prices in recent periods. The natural gas price was found to become more stable and drift away from its historical relationship with oil.

Dang, Trang Phuong Th 1977-

2012-12-01T23:59:59.000Z

294

Overview of existing residential energy-efficiency rating systems and measuring tools  

SciTech Connect

Three categories of rating systems/tools were identified: prescriptive, calculational, and performance. Prescriptive systems include rating systems that assign points to various conservation features. Most systems that have been implemented to date have been prescriptive systems. The vast majority of these are investor-owned utility programs affiliated with the National Energy Watch program of the Edison Electric Institute. The calculational category includes computational tools that can be used to estimate energy consumption. This estimate could then be transformed, probably by indexing, into a rating. The available computational tools range from very simple to complex tools requiring use of a main-frame computer. Performance systems refer to residential energy-efficiency ratings that are based on past fuel consumption of a home. There are few of these systems. For each identified system/tool, the name, address, and telephone number of the developer is included. In addition, relevant publications discussing the system/tool are cited. The extent of field validation/verification of individual systems and tools is discussed. In general, there has been little validation/verification done. A bibliography of literature relevant to the use and implementation of a home energy rating system is also included.

Hendrickson, P.L.; Garrett-Price, B.A.; Williams, T.A.

1982-10-01T23:59:59.000Z

295

Dynamic Scheduling of Skippable Periodic Tasks with Energy Efficiency in Weakly Hard Real-Time System  

E-Print Network (OSTI)

Energy consumption is a critical design issue in real-time systems, especially in battery- operated systems. Maintaining high performance, while extending the battery life between charges is an interesting challenge for system designers. Dynamic Voltage Scaling (DVS) allows a processor to dynamically change speed and voltage at run time, thereby saving energy by spreading run cycles into idle time. Knowing when to use full power and when not, requires the cooperation of the operating system scheduler. Usually, higher processor voltage and frequency leads to higher system throughput while energy reduction can be obtained using lower voltage and frequency. Instead of lowering processor voltage and frequency as much as possible, energy efficient real-time scheduling adjusts voltage and frequency according to some optimization criteria, such as low energy consumption or high throughput, while it meets the timing constraints of the real-time tasks. As the quantity and functional complexity of battery powered porta...

Baskaran, Santhi

2010-01-01T23:59:59.000Z

296

Analysis of space heating and domestic hot water systems for energy-efficient residential buildings  

DOE Green Energy (OSTI)

An analysis of the best ways of meeting the space heating and domestic hot water (DHW) needs of new energy-efficient houses with very low requirements for space heat is provided. The DHW load is about equal to the space heating load in such houses in northern climates. The equipment options which should be considered are discussed, including new equipment recently introduced in the market. It is concluded that the first consideration in selecting systems for energy-efficient houses should be identification of the air moving needs of the house for heat distribution, heat storage, ventilation, and ventilative cooling. This is followed, in order, by selection of the most appropriate distribution system, the heating appliances and controls, and the preferred energy source, gas, oil, or electricity.

Dennehy, G

1983-04-01T23:59:59.000Z

297

Alternative fuel transit buses: The Pierce Transit Success Story  

DOE Green Energy (OSTI)

The Pierce transit program for operating mass transit buses on compressed natural gas (CNG) is described. Cost, reliability, fuel efficiency, emission of combustion products, and future trends are discussed.

NONE

1996-10-01T23:59:59.000Z

298

Essays on transition challenges for alternative propulsion vehicles and transportation systems  

E-Print Network (OSTI)

Technology transitions require the formation of a self-sustaining market through alignment of consumers' interests, producers' capabilities, infrastructure development, and regulations. In this research I develop a broad ...

Struben, Jeroen J. R

2006-01-01T23:59:59.000Z

299

The relationship between rail transit ridership and built environment and transportation system  

E-Print Network (OSTI)

Public transportation is an effective tool to tackle many urban transportation problems. Due to its higher capacity and reliability, rail transit often serves as the main means to connect major trip origins and destinations ...

Chen, Szu-han

2013-01-01T23:59:59.000Z

300

Transitional failure of carbon nanotube systems under a combination of tension and torsion  

Science Conference Proceedings (OSTI)

Transitional failure envelopes of single- and double-walled carbon nanotubes under combined tension-torsion are predicted using classical molecular dynamics simulations. The observations reveal that while the tensile failure load decreases with combined ...

Byeong-Woo Jeong

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Implementation of advanced transit traveler information systems in the United States and Canada : practice and prospects  

E-Print Network (OSTI)

Over the past few years, public transit agencies across the United States and Canada have increasingly implemented methods for passengers to access traveler information using new media and personal mobile communications ...

Rizos, Anthony Charles

2010-01-01T23:59:59.000Z

302

Efficient energy transfer in light-harvesting systems, I: optimal temperature, reorganization energy and spatial–temporal correlations  

E-Print Network (OSTI)

Understanding the mechanisms of efficient and robust energy transfer in light-harvesting systems provides new insights for the optimal design of artificial systems. In this paper, we use the Fenna–Matthews–Olson (FMO) ...

Wu, Jianlan

303

Improving Energy Efficiency of Compressed Air System Based on System Audit  

E-Print Network (OSTI)

be a significant source of wasted energy in an industrialto being a source of wasted energy and money, leaks can alsofor about 3.2% of system energy wasted. Figure 5 Excessive

Shanghai, Hongbo Qin; McKane, Aimee

2008-01-01T23:59:59.000Z

304

Cost Effective, High Efficiency Integrated Systems Approach to Auxilliary Electric Motors  

DOE Green Energy (OSTI)

The CARAT program, carried out by Kinetic Art & Technology Corporation (KAT), has been one of the most commercially successful KAT R&D programs to date. Based on previous development of its technology, KAT designed, constructed and tested a highly efficient motor and controller system under this CARAT program with supplemental commercial funding. Throughout this CARAT effort, the technical objectives have been refined and refocused. Some objectives have been greatly expanded, while others have been minimized. The determining factor in all decisions to refocus the objectives was the commercial need, primarily the needs of KAT manufacturing partners. Several companies are employing the resulting CARAT motor and controller designs in prototypes for commercial products. Two of these companies have committed to providing cost share in order to facilitate the development. One of these companies is a major manufacturing company developing a revolutionary new family of products requiring the ultra-high system efficiency achievable by the KAT motor and controller technologies (known as Segmented ElectroMagnetic Array, or SEMA technology). Another company requires the high efficiency, quiet operation, and control characteristics afforded by the same basic motor and controller for an advanced air filtration product. The combined annual production requirement projected by these two companies exceeds one million units by 2005.

Roy Kessinger Jr.; Keith Seymour; Kanchan Angal; Jason Wolf; Steve Brewer; Leonard Schrank

2003-09-26T23:59:59.000Z

305

Energy Efficient Design of Portable Wireless Systems Tajana Simunic Haris Vikalo Peter Glynny Giovanni De Micheli  

E-Print Network (OSTI)

to force the power state transition according to the power management policy. A heuristic power management the transition to a low power state as soon as a com- ponent becomes idle if the predictor estimates, the power manager waits until the time jh where the probability of transition to o state, p(j), is greater

Simunic, Tajana

306

High efficiency vapor-fed AMTEC system for direct conversion. Final report  

DOE Green Energy (OSTI)

The Alkali Metal Thermal to Electric Converter (AMTEC) is a high temperature, high efficiency system for converting thermal to electrical energy, with no moving parts. It is based on the unique properties of {beta}{double_prime}-alumina solid electrolyte (BASE), which is an excellent conductor of sodium ions, but an extremely poor conductor of electrons. When the inside of the BASE is maintained at a higher temperature and pressure, a concentration gradient is created across the BASE. Electrons and sodium atoms cannot pass through the BASE. However, the sodium atoms are ionized, and the sodium ions move through the BASE to the lower potential (temperature) region. The electrons travel externally to the AMTEC cell, providing power. There are a number of potential advantages to a wick-pumped, vapor-fed AMTEC system when compared with other designs. A wick-pumped system uses capillary forces to passively return liquid to the evaporator, and to distribute the liquid in the evaporator. Since the fluid return is self-regulating, multiple BASE tubes can use a single remote condenser, potentially improving efficiency in advanced AMTEC designs. Since the system is vapor-fed, sodium vapor is supplied at a uniform temperature and flux to the BASE tube, even with non-uniform heat fluxes and temperatures at the evaporator. The primary objective of the Phase 2 program was to develop wick-pumped AMTEC cells. During the program, procedures to fabricate wicks with smaller pore sizes were developed, to allow operation of an AMTEC cell at 800 C. A revised design was made for a High-Temperature, Wick-Fed AMTEC cell. In addition to the smaller wick pore size, several other changes were made to increase the cell efficiency: (1) internal artery return of condensate; (2) high temperature electrical feedthrough; and (3) separate heat pipe for providing heat to the BASE.

Anderson, W.G.; Bland, J.J.

1997-05-23T23:59:59.000Z

307

An Efficient LED System-in-Module for General Lighting Applications  

SciTech Connect

The objective of the project was to realize an LED-based lighting technology platform for general illumination, starting with LED chips, and integrating the necessary technologies to make compact, user-friendly, high-efficiency, energy-saving sources of controlled white (or variable-colored) light. The project is to build the system around the LEDs, and not to work on the LEDs themselves, in order that working products can be introduced soon after the LEDs reach suitable efficiency for mass-production of high-power light sources for general illumination. Because the light sources are intended for general illumination, color must be accurately maintained, requiring feedback control in the electronics. The project objective has been realized and screw base demonstrators, based on the technology developed in the project, have been built.

2008-09-14T23:59:59.000Z

308

Energy Efficiency of large Cryogenic Systems: the LHC Case and Beyond  

E-Print Network (OSTI)

Research infrastructures for high-energy and nuclear physics, nuclear fusion and production of high magnetic fields are increasingly based on applied superconductivity and associated cryogenics in their quest for scientific breakthroughs at affordable capital and operation costs, a condition for their acceptance and sustained funding by society. The thermodynamic penalty for operating at low temperature makes energy efficiency a key requirement for their large cryogenic systems, from conceptual design to procurement, construction and operation. Meeting this requirement takes a combined approach on several fronts in parallel: management of heat loads and sizing of cooling duties, distribution of cooling power matching the needs of the superconducting devices, efficient production of refrigeration, optimal control resting on precise instrumentation and diagnostics, as well as a targeted industrial procurement policy. The case of the Large Hadron Collider (LHC) at CERN is presented. Potential improvements for fu...

Claudet, S; Ferlin, G; Lebrun, P; Tavian, L; Wagner, U

2013-01-01T23:59:59.000Z

309

Variational description of Gibbs-non-Gibbs dynamical transitions for spin-flip systems with a Kac-type interaction  

E-Print Network (OSTI)

We continue our study of Gibbs-non-Gibbs dynamical transitions. In the present paper we consider a system of Ising spins on a large discrete torus with a Kac-type interaction subject to an independent spin-flip dynamics (infinite-temperature Glauber dynamics). We show that, in accordance with the program outlined in \\cite{vEFedHoRe10}, in the thermodynamic limit Gibbs-non-Gibbs dynamical transitions are \\emph{equivalent} to bifurcations in the set of global minima of the large-deviation rate function for the trajectories of the empirical density \\emph{conditional} on their endpoint. More precisely, the time-evolved measure is non-Gibbs if and only if this set is not a singleton for \\emph{some} value of the endpoint. A partial description of the possible scenarios of bifurcation is given, leading to a characterization of passages from Gibbs to non-Gibbs and vice versa, with sharp transition times. Our analysis provides a conceptual step-up from our earlier work on Gibbs-non-Gibbs dynamical transitions for the Curie-Weiss model, where the mean-field interaction allowed us to focus on trajectories of the empirical magnetization rather than the empirical density.

Roberto Fernández; Frank den Hollander; Julián Martínez

2013-09-14T23:59:59.000Z

310

Joint System Prognostics For Increased Efficiency And Risk Mitigation In Advanced Nuclear Reactor Instrumentation and Control  

SciTech Connect

The science of prognostics is analogous to a doctor who, based on a set of symptoms and patient tests, assesses a probable cause, the risk to the patient, and a course of action for recovery. While traditional prognostics research has focused on the aspect of hydraulic and mechanical systems and associated failures, this project will take a joint view in focusing not only on the digital I&C aspect of reliability and risk, but also on the risks associated with the human element. Model development will not only include an approximation of the control system physical degradation but also on human performance degradation. Thus the goal of the prognostic system is to evaluate control room operation; to identify and potentially take action when performance degradation reduces plant efficiency, reliability or safety.

Donald D. Dudenhoeffer; Tuan Q. Tran; Ronald L. Boring; Bruce P. Hallbert

2006-08-01T23:59:59.000Z

311

Energy Efficient Building Ventilation Systems: Innovative Building-Integrated Enthalpy Recovery  

Science Conference Proceedings (OSTI)

BEETIT Project: A2 is developing a building moisture and heat exchange technology that leverages a new material and design to create healthy buildings with lower energy use. Commercial building owners/operators are demanding buildings with greater energy efficiency and healthier indoor environments. A2 is developing a membrane-based heat and moisture exchanger that controls humidity by transferring the water vapor in the incoming fresh air to the drier air leaving the building. Unlike conventional systems, A2 locates the heat and moisture exchanger within the depths of the building’s wall to slow down the air flow and increase the surface area that captures humidity, but with less fan power. The system’s integration into the wall reduces the size and demand on the air conditioning equipment and increases liable floor area flexibility.

None

2010-10-15T23:59:59.000Z

312

Truck Essential Power Systems Efficiency Improvements for Medium-Duty Trucks  

DOE Green Energy (OSTI)

With a variety of hybrid vehicles available in the passenger car market, electric technologies and components of that scale are becoming readily available. Commercial vehicle segments have lagged behind passenger car markets, leaving opportunities for component and system development. Escalating fuel prices impact all markets and provide motivation for OEMs, suppliers, customers, and end-users to seek new techniques and technologies to deliver reduced fuel consumption. The research presented here specifically targets the medium-duty (MD), Class 4-7, truck market with technologies aimed at reducing fuel consumption. These technologies could facilitate not only idle, but also parasitic load reductions. The development efforts here build upon the success of the More Electric Truck (MET) demonstration program at Caterpillar Inc. Employing a variety of electric accessories, the MET demonstrated the improvement seen with such technologies on a Class 8 truck. The Truck Essential Power Systems Efficiency Improvements for Medium-Duty Trucks (TEPS) team scaled the concepts and successes of MET to a MD chassis. The team designed an integrated starter/generator (ISG) package and energy storage system (ESS), explored ways to replace belt and gear-driven accessory systems, and developed supervisory control algorithms to direct the usage of the generated electricity and system behavior on the vehicle. All of these systems needed to fit within the footprint of a MD vehicle and be compatible with the existing conventional systems to the largest extent possible. The overall goal of this effort was to demonstrate a reduction in fuel consumption across the drive cycle, including during idle periods, through truck electrification. Furthermore, the team sought to evaluate the benefits of charging the energy storage system during vehicle braking. The vehicle features an array of electric accessories facilitating on-demand, variable actuation. Removal of these accessories from the belt or geartrain of the engine yields efficiency improvements for the engine while freeing those accessories to perform at their individual peak efficiencies to meet instantaneous demand. The net result is a systems approach to fuel usage optimization. Unique control algorithms were specifically developed to capitalize on the flexibility afforded by the TEPS architecture. Moreover, the TEPS truck technology mixture exhibits a means to supplant current accessory power sources such as on-board or trailer-mounted gasoline-powered generators or air compressors. Such functionality further enhances the value of the electric systems beyond the fuel savings alone. To demonstrate the fuel economy improvement wrought via the TEPS components, vehicle fuel economy testing was performed on the nearly stock (baseline) truck and the TEPS truck. Table 1 illustrates the fuel economy gains produced by the TEPS truck electrification. While the fuel economy results shown in Table 1 do reflect specific test conditions, they show that electrification of accessory hardware can yield significant fuel savings. In this case, the savings equated to a 15 percent reduction in fuel consumption during controlled on-road testing. Truck electrification allows engine shutdown during idle conditions as well as independent on-demand actuation of accessory systems. In some cases, independent actuation may even include lack of operation, a feature not always present in mechanically driven components. This combination of attributes allows significant improvements in system efficiency and the fuel economy improvements demonstrated by the TEPS team.

Larry Slone; Jeffery Birkel

2007-12-31T23:59:59.000Z

313

Thermal-Electric Conversion Efficiency of the Dish/AMTEC Solar Thermal Power System in Wind Condition  

Science Conference Proceedings (OSTI)

The dish/AMTEC solar thermal power system is a newly proposed solar energy utilization system that enables the direct thermal-electric conversion. The performance of the solar dish/AMTEC system in wind condition has been theoretically evaluated in addition ... Keywords: dish/AMTEC solar thermal power system, efficiency, thermal-electric conversion, wind condition

Lan Xiao; Shuang-Ying Wu; You-Rong Li

2012-07-01T23:59:59.000Z

314

Minimizing Failures While Maintaining Efficiency of Complex Interactive Networks and Systems: EPRI/DoD Complex Interactive Networks/ Systems Initiative; First Annual Report  

Science Conference Proceedings (OSTI)

This is the first annual report from the EPRI/DOD Complex Interactive Networks/Systems Initiative. The report describes research progress in minimizing failures while maintaining efficiency of complex interactive networks and systems.

2000-05-26T23:59:59.000Z

315

Efficiency Improvement through Reduction in Friction and Wear in Powertrain Systems  

DOE Green Energy (OSTI)

The objective of this project is to improve the efficiency of truck drivelines through reduction of friction and parasitic losses in transmission and drive axles. Known efficiencies for these products exceeded 97 percent, so the task was not trivial. The project relied on a working relationship between modeling and hardware testing. Modeling was to shorten the development cycle by guiding the selection of materials, processes and strategies. Bench top and fixture tests were to validate the models. Modeling was performed at a world class, high academic level, but in the end, modeling did not impact the hardware development as much as intended. Insights leading to the most significant accomplishments came from bench top and fixture tests and full scale dynamometer tests. A key development in the project was the formulation of the implementation strategy. Five technical elements with potential to minimize friction and parasitic losses were identified. These elements included churning, lubrication, surface roughness, coatings and textures. An interesting fact is that both Caterpillar and Eaton independently converged on the same set of technical elements in formulating their implementation strategies. Exploiting technical elements of the implementation strategy had a positive impact on transmission and drive axle efficiencies. During one dynamometer test of an Eaton Best Tech 1 transmission, all three gear ranges tested: Under drive, direct drive and over drive, showed efficiencies greater than 99 percent. Technology boosts to efficiency for transmissions reached 1 percent, while efficiency improvements to drive axle pushed 2 percent. These advancements seem small, but the accomplishment is large considering that these products normally run at greater than 97 percent efficiency. Barriers and risks to implementing these technology elements are clear. Schemes using a low fill sump and spray tubes endanger the gears and bearings by lubricant starvation. Gear coatings have exhibited durability issues, stripping away under conditions less demanding than 750,000 miles in service on the road. Failed coatings compound the problem by contaminating the lubricant with hard particles. Under the most severe conditions, super finished surfaces may polish further, reaching a surface roughness unable to support the critical oil film thickness. Low viscosity and low friction lubricants may not protect the gears and bearings adequately leading to excessive pitting, wear and noise. Additives in low friction oils may not stay in solution or suspended thus settling to the bottom and unavailable when they are needed most. Technical barriers and risks can be overcome through engineering, but two barriers remain formidable: (1) cost of the technology and (2) convincing fleet owners that the technology provides a tangible benefit. Dry sumps lower lubricant operating temperatures so the removal of heat exchangers and hoses and reduced demand on engine cooling systems justify their use. The benefits of surface texturing are varied and remain unproven. Lubricant costs seem manageable, but the cost of super finishing and gear coating are high. These are issues of scale and processing technology. Going across the board with gear super finishing and coating will reduce costs. Pushing the envelope to applications with higher torque and higher power density should drive the adoption of these technologies. Fleet owners are an educated and seasoned lot. Only technology measureable in dollars returned is used on truck fleets. To convince fleet owners of the benefit of these technologies, new precision in measuring fuel efficiency must be introduced. Legislation for a minimum standard in truck miles per gallon would also enable the use of these technologies. Improving the efficiency of truck transmissions and axle will make a noticeable impact on the fuel consumption by heavy vehicles in the United States. However, the greatest benefit will come when all the individual efficiency technologies like hybrid power, aerodynamic fairings, auxiliary power units, super

Michael Killian

2009-09-30T23:59:59.000Z

316

Pilot States Program report: Home energy ratings systems and energy-efficient mortgages  

SciTech Connect

This report covers the accomplishments of the home energy ratings systems/energy-efficient mortgages (HERS/EEMs) pilot states from 1993 through 1998, including such indicators as funding, ratings and EEMs achieved, active raters, and training and marketing activities. A brief description of each HERS program's evolution is included, as well as their directors' views of the programs' future prospects. Finally, an analysis is provided of successful HERS program characteristics and factors that appear to contribute to HERS program success.

Farhar, B.

2000-04-04T23:59:59.000Z

317

An efficient all-optical switch using a lambda atom in a cavity QED system  

E-Print Network (OSTI)

We propose an all-optical switch constructed from a two-mode optical resonator containing a strongly coupled, three-state system. The coupling allows a weak laser drive to incoherently control the transmission of a much stronger signal laser into (and through) the resonator. We demonstrate that in this simple setup the presence of a control drive with one tenth the power of the signal drive can induce near complete reflection of the signal, while its absence allows for near complete transmission. The switch can also be operated as a set-reset relay with two control inputs that efficiently drive the switch into either the reflecting or the transmitting state

Anne E. B. Nielsen; Joseph Kerckhoff

2011-06-12T23:59:59.000Z

318

An efficient all-optical switch using a lambda atom in a cavity QED system  

E-Print Network (OSTI)

We propose an all-optical switch constructed from a two-mode optical resonator containing a strongly coupled, three-state system. The coupling allows a weak laser drive to incoherently control the transmission of a much stronger signal laser into (and through) the resonator. We demonstrate that in this simple setup the presence of a control drive with one tenth the power of the signal drive can induce near complete reflection of the signal, while its absence allows for near complete transmission. The switch can also be operated as a set-reset relay with two control inputs that efficiently drive the switch into either the reflecting or the transmitting state

Nielsen, Anne E B

2011-01-01T23:59:59.000Z

319

The trigger system of the Pierre Auger Surface Detector: operation, efficiency and stability  

E-Print Network (OSTI)

The trigger system of the Surface Detector (SD) of the Pierre Auger Observatory is described, from the identification of candidate showers ($E>1$ EeV) at the level of a single station, among a huge background (mainly single muons), up to the selection of real events and the rejection of random coincidences at a higher central trigger level (including the reconstruction accuracy). Efficiency of a single station trigger is evaluated using real data , and the high performance of event selection hierarchy will be demonstrated.

D. Allard; E. Armengaud; I. Allekotte; P. Allison; J. Aublin; M. Ave; P. Bauleo; J. Beatty; T. Beau; X. Bertou; P. Billoir; C. Bonifazi; A. Chou; J. Chye; S. Dagoret-Campagne; A. Dorofeev; P. L. Ghia; M. Gomez Berisso; A. Gorgi; J. C. Hamilton; J. Harton; R. Knapik; C. Lachaud; I. Lhenry-Yvon; A. Letessier-Selvon; J. Matthews; C. Medina; R. Meyhandan; G. Navarra; D. Nitz; E. Parizot; B. Revenu; Z. Szadkowski; T. Yamamoto

2005-10-11T23:59:59.000Z

320

Improving the Efficiency of Die Casting Machine Hydraulic Systems with the Retrofit of Adjustable Frequency Drives  

E-Print Network (OSTI)

Die casting is a common method of light metal processing which is used to produce accurately dimensioned, sharply defined metal parts. Most die casting machines in use today utilize a complex hydraulic system to perform the necessary work required for the process. The pressure and flow rate demands on the hydraulic system vary significantly throughout the cycle. Many older systems are greatly oversized so that they are able to meet the peak hydraulic demand at any point. These systems operate inefficiently because there is typically no way to limit the hydraulic capacity during periods of low demand. As a result, fluid is throttled to lower pressures and excess fluid flow is routed directly back to the system reservoir, wasting motor energy and increasing the thermal load on the cooling system. One option for improving the efficiency of older die casting machines currently in use is the retrofit of an adjustable frequency drive, or AFD. An AFD allows the speed of the pump motor to be varied, changing the pump output to suit the cycle demands. This minimizes the amount of wasted energy without affecting other process parameters. This paper will discuss the die casting process and examine the energy savings potential of retrofitting die casting machines with adjustable frequency drives.

Ambs, L.; Kosanovic, D.; Edberg, C.

1999-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Injection Timing Effects on Brake Fuel Conversion Efficiency and Engine System's Respones  

E-Print Network (OSTI)

Societal concerns on combustion-based fuel consumption are ever-increasing. With respect to internal combustion engines, this translates to a need to increase brake fuel conversion efficiency (BFCE). Diesel engines are a relatively efficient internal combustion engine to consider for numerous applications, but associated actions to mitigate certain exhaust emissions have generally deteriorated engine efficiency. Conventionally, diesel engine emission control has centered on in-cylinder techniques. Although these continue to hold promise, the industry trend is presently favoring the use of after-treatment devices which create new opportunities to improve the diesel engine's brake fuel conversion efficiency. This study focuses on injection timing effects on the combustion processes, engine efficiency, and the engine system's responses. The engine in the study is a medium duty diesel engine (capable of meeting US EPA Tier III off road emission standards) equipped with common rail direct fuel injection, variable geometry turbo charging, and interfaced with a custom built engine controller. The study found that injection timing greatly affected BFCE by changing the combustion phasing. BFCE would increase up to a maximum then begin to decrease as phasing became less favorable. Combustion phasing would change from being mostly mixing controlled combustion to premixed combustion as injection timing would advance allowing more time for fuel to mix during the ignition delay. Combustion phasing, in turn, would influence many other engine parameters. As injection timing is advanced, in-cylinder temperatures and pressures amplify, and intake and exhaust manifold pressures deteriorate. Rate of heat release and rate of heat transfer increase when injection timing is advanced. Turbocharger speed falls with the advancing injection timing. Torque, however, rose to a maximum then fell off again even though engine speed and fueling rate were held constant between different injection timings. Interestingly, the coefficient of heat transfer changes from a two peak curve to a smooth one peak curve as the injection timing is advanced further. The major conclusion of the study is that injection advance both positively and negatively influences the diesel engine's response which contributes to the brake fuel conversion efficiency.

McLean, James Elliott

2011-08-01T23:59:59.000Z

322

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-Print Network (OSTI)

in thermal energy conversion efficiency over present solarsolar thermal- photovoltaic co-generation scheme could have potentially very high solar-to-electric efficiency.solar-to-electric conversion efficiencies are attained and no thermal

Ho, Tony

2012-01-01T23:59:59.000Z

323

KELT-2Ab: A HOT JUPITER TRANSITING THE BRIGHT (V = 8.77) PRIMARY STAR OF A BINARY SYSTEM  

Science Conference Proceedings (OSTI)

We report the discovery of KELT-2Ab, a hot Jupiter transiting the bright (V = 8.77) primary star of the HD 42176 binary system. The host is a slightly evolved late F-star likely in the very short-lived 'blue-hook' stage of evolution, with T{sub eff} = 6148 {+-} 48 K, log g = 4.030{sup +0.015}{sub -0.026} and [Fe/H] = 0.034 {+-} 0.78. The inferred stellar mass is M{sub *} = 1.314{sup +0.063}{sub -0.060} M{sub Sun} and the star has a relatively large radius of R{sub *} = 1.836{sup +0.066}{sub -0.046} R{sub Sun }. The planet is a typical hot Jupiter with period 4.1137913 {+-} 0.00001 days and a mass of M{sub P} = 1.524 {+-} 0.088 M{sub J} and radius of R{sub P} = 1.290{sup +0.064}{sub -0.050} R{sub J}. This is mildly inflated as compared to models of irradiated giant planets at the {approx}4 Gyr age of the system. KELT-2A is the third brightest star with a transiting planet identified by ground-based transit surveys, and the ninth brightest star overall with a transiting planet. KELT-2Ab's mass and radius are unique among the subset of planets with V McLaughlin measurements, which should have an amplitude of {approx}44 m s{sup -1}.

Beatty, Thomas G.; Gaudi, B. Scott; Gould, Andrew [Department of Astronomy, Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States); Pepper, Joshua; Siverd, Robert J.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Eastman, Jason D.; Fulton, Benjamin J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Bieryla, Allyson; Latham, David W.; Berlind, Perry; Calkins, Michael L.; Esquerdo, Gilbert A.; Furesz, Gabor; Geary, John C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Buchhave, Lars A. [Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 21S00 Copenhagen (Denmark); Jensen, Eric L. N. [Department of Physics and Astronomy, Swarthmore College, Swarthmore, PA 19081 (United States); Manner, Mark [Spot Observatory, Nunnelly, TN 37137 (United States); Collins, Karen [Department of Physics and Astronomy, University of Louisville, Louisville, KY 40292 (United States); DePoy, Darren L. [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); and others

2012-09-10T23:59:59.000Z

324

An energy-efficient differential flip-flop for deeply pipelined systems  

E-Print Network (OSTI)

Abstract — Deeply pipelined systems require flip-flops with low latency and power consumption. Often, the flip-flop must supply both inverted and non-inverted signals to subsequent logic. Generating both outputs at the same time improves performance by equalizing the worst-case delays. In this paper, we present a novel differential flip-flop for deeply pipelined systems. The circuit uses cross-coupled p-transistors as pull-up devices to achieve high energy efficiency. We simulated the design in 90-nm CMOS technology to determine the delay and power consumption. We then repeated the analysis with four other differential flip-flops that produce symmetric outputs. The proposed design achieves the best power-delay product of the five alternatives. I.

Mitchell J. Myjak; José G. Delgado-frias; Seon Kwang Jeon

2006-01-01T23:59:59.000Z

325

Similarity and generalized analysis of efficiencies of thermal energy storage systems  

SciTech Connect

This paper examined the features of three typical thermal storage systems including: (1) direct storage of heat transfer fluid in containers, (2) storage of thermal energy in a packed bed of solid filler material, with energy being carried in/out by a flowing heat transfer fluid which directly contacts the packed bed, and (3) a system in which heat transfer fluid flows through tubes that are imbedded into a thermal storage material which may be solid, liquid, or a mixture of the two. The similarity of the three types of thermal storage systems was discussed, and generalized energy storage governing equations were introduced in both dimensional and dimensionless forms. The temperatures of the heat transfer fluid during energy charge and discharge processes and the overall energy storage efficiencies were studied through solution of the energy storage governing equations. Finally, provided in the paper are a series of generalized charts bearing curves for energy storage effectiveness against four dimensionless parameters grouped up from many of the thermal storage system properties including dimensions, fluid and thermal storage material properties, as well as the operational conditions including mass flow rate of the fluid, and the ratio of energy charge and discharge time periods. Engineers can conveniently look up the charts to design and calibrate the size of thermal storage tanks and operational conditions without doing complicated individual modeling and computations. It is expected that the charts will serve as standard tools for thermal storage system design and calibration.

Peiwen Li; Jon Van Lew; Cholik Chan; Wafaa Karaki; Jake Stephens; J. E. O'Brien

2012-03-01T23:59:59.000Z

326

Ultra Clean 1.1MW High Efficiency Natural Gas Engine Powered System  

Science Conference Proceedings (OSTI)

Dresser, Inc. (GE Energy, Waukesha gas engines) will develop, test, demonstrate, and commercialize a 1.1 Megawatt (MW) natural gas fueled combined heat and power reciprocating engine powered package. This package will feature a total efficiency > 75% and ultra low CARB permitting emissions. Our modular design will cover the 1 – 6 MW size range, and this scalable technology can be used in both smaller and larger engine powered CHP packages. To further advance one of the key advantages of reciprocating engines, the engine, generator and CHP package will be optimized for low initial and operating costs. Dresser, Inc. will leverage the knowledge gained in the DOE - ARES program. Dresser, Inc. will work with commercial, regulatory, and government entities to help break down barriers to wider deployment of CHP. The outcome of this project will be a commercially successful 1.1 MW CHP package with high electrical and total efficiency that will significantly reduce emissions compared to the current central power plant paradigm. Principal objectives by phases for Budget Period 1 include: • Phase 1 – market study to determine optimum system performance, target first cost, lifecycle cost, and creation of a detailed product specification. • Phase 2 – Refinement of the Waukesha CHP system design concepts, identification of critical characteristics, initial evaluation of technical solutions, and risk mitigation plans. Background

Zurlo, James; Lueck, Steve

2011-08-31T23:59:59.000Z

327

Combining compiler and operating system support for energy efficient i/o on embedded platforms  

E-Print Network (OSTI)

Mobile and embedded platforms have experienced dramatic advances in capabilities, largely due to the development of associated peripheral devices for storage and communication. The incorporation of these I/O devices has increased the overall power envelope of these platforms. In fact, system-level power consumption of mobile platforms is often dominated by peripheral devices. Since battery technologies alone have been unable to provide the lifetimes required by many platforms, in order to conserve energy, most devices provide the ability to transition into low power states during idle periods. The resulting energy savings are heavily dependent upon the lengths and number of idle periods experienced by a device. This paper presents an infrastructure designed to take advantage of device low power states by increasing the burstiness of device accesses and idle periods to provide a reduced power profile, and thereby an improvement in battery life. Our approach combines compiler-based source modifications with operating system support to implement a dynamic solution for enhanced energy consumption. We evaluate our infrastructure on an XScale-based embedded platform with a Linux implementation. 1.

Ripal Nathuji

2005-01-01T23:59:59.000Z

328

Interplay between electronic structure and catalytic activity in transition metal oxide model system  

E-Print Network (OSTI)

The efficiency of many energy storage and conversion technologies, such as hydrogen fuel cells, rechargeable metal-air batteries, and hydrogen production from water splitting, is limited by the slow kinetics of the oxygen ...

Suntivich, Jin

2012-01-01T23:59:59.000Z

329

National Renewable Energy Laboratory's Hydrogen Technologies and Systems Center is Helping to Facilitate the Transition to a New Energy Future  

DOE Green Energy (OSTI)

The Hydrogen Technologies and Systems Center (HTSC) at the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) uses a systems engineering and integration approach to hydrogen research and development to help the United States make the transition to a new energy future - a future built on diverse and abundant domestic renewable resources and integrated hydrogen systems. Research focuses on renewable hydrogen production, delivery, and storage; fuel cells and fuel cell manufacturing; technology validation; safety, codes, and standards; analysis; education; and market transformation. Hydrogen can be used in fuel cells to power vehicles and to provide electricity and heat for homes and offices. This flexibility, combined with our increasing demand for energy, opens the door for hydrogen power systems. HTSC collaborates with DOE, other government agencies, industry, communities, universities, national laboratories, and other stakeholders to promote a clean and secure energy future.

Not Available

2011-01-01T23:59:59.000Z

330

High-transition-temperature superconductors in the Nb-Al-Ge system  

DOE Patents (OSTI)

The patent describes superconducting materials of the nominal composition Nb(x)Al(y)Ge(l-y), where x is in the range of 1.9 to 2.8 and y is in the range of 0.5 to 0.9, having transition temperatures in the 19 -20K. range which are readily produced by annealing arc-melted compositions, or cold-pressed, heat-treated compositions at moderate temperatures for reasonably long times (about 50 hours).

Giorgi, A.L.; Szklarz, E.G.

1972-09-26T23:59:59.000Z

331

Improve Motor System Efficiency with MotorMaster+, Software Tools for Industry, Industrial Technologies Program (ITP) (Fact Sheet)  

SciTech Connect

This fact sheet describes how the Industrial Technologies Program MotorMaster+ software tool aids industrial plants with finding energy-efficient motor replacement options and managing motor systems.

Not Available

2008-12-01T23:59:59.000Z

332

Energy-efficient mortgages and home energy rating systems: A report on the nation`s progress  

SciTech Connect

This report summarizes progress throughout the nation in establishing voluntary programs linking home energy rating systems (HERS) and energy-efficient mortgages (EEMs). These programs use methods for rating the energy efficiency of new and existing homes and predicting energy cost savings so lenders can factor in energy cost savings when underwriting mortgages. The programs also encourage lenders to finance cost-effective energy-efficiency improvements to existing homes with low-interest mortgages or other instruments. The money saved on utility bills over the long term can more than offset the cost of such energy-efficiency improvements. The National Collaborative on HERS and EEMs recommended that this report be prepared.

Farhar, B.C.; Eckert, J.

1993-09-01T23:59:59.000Z

333

Rimac: A novel redundancybased hierarchical cache architecture for energy efficient, high performance storage systems  

E-Print Network (OSTI)

Energy efficiency becomes increasingly important in today’s high-performance storage systems. It can be challenging to save energy and improve performance at the same time in conventional (i.e. single-rotation-rate) disk-based storage systems. Most existing solutions compromise performance for energy conservation. In this paper, we propose a redundancy-based, two-level I/O cache architecture called RIMAC to address this problem. The idea of RIMAC is to enable data on the standby disk to be recovered by accessing data in the two-level I/O cache or on currently active/idle disks. At both cache and disk levels, RIMAC dynamically transforms accesses toward standby disks by exploiting parity redundancy in parity-based redundant disk arrays. Because I/O requests that require physical accesses on standby disks involve long waiting time and high power consumption for disk spin-up (tens of seconds for SCSI disks), transforming those requests to accesses in a two-level, collaborative I/O cache or on active disks can significantly improve both energy efficiency and performance. In RIMAC, we developed i) two power-aware read request transformation schemes called Transformable Read in Cache (TRC) and Transformable Read on Disk (TRD), ii) a poweraware write request transformation policy for parity update and (iii) a second-chance parity cache replacement algorithm to improve request transformation rate. We evaluated RI-MAC by augmenting a validated storage system simulator, disksim. For several real-life server traces including HP’s cello99, TPC-D and SPC’s search engine, RIMAC is shown to reduce energy consumption by up to 33 % and simultaneously improve the average response time by up to 30%. 1.

Xiaoyu Yao; Jun Wang

2006-01-01T23:59:59.000Z

334

GUIDE TO CALCULATING TRANSPORT EFFICIENCY OF AEROSOLS IN OCCUPATIONAL AIR SAMPLING SYSTEMS  

SciTech Connect

This report will present hand calculations for transport efficiency based on aspiration efficiency and particle deposition losses. Because the hand calculations become long and tedious, especially for lognormal distributions of aerosols, an R script (R 2011) will be provided for each element examined. Calculations are provided for the most common elements in a remote air sampling system, including a thin-walled probe in ambient air, straight tubing, bends and a sample housing. One popular alternative approach would be to put such calculations in a spreadsheet, a thorough version of which is shared by Paul Baron via the Aerocalc spreadsheet (Baron 2012). To provide greater transparency and to avoid common spreadsheet vulnerabilities to errors (Burns 2012), this report uses R. The particle size is based on the concept of activity median aerodynamic diameter (AMAD). The AMAD is a particle size in an aerosol where fifty percent of the activity in the aerosol is associated with particles of aerodynamic diameter greater than the AMAD. This concept allows for the simplification of transport efficiency calculations where all particles are treated as spheres with the density of water (1 g?cm-3). In reality, particle densities depend on the actual material involved. Particle geometries can be very complicated. Dynamic shape factors are provided by Hinds (Hinds 1999). Some example factors are: 1.00 for a sphere, 1.08 for a cube, 1.68 for a long cylinder (10 times as long as it is wide), 1.05 to 1.11 for bituminous coal, 1.57 for sand and 1.88 for talc. Revision 1 is made to correct an error in the original version of this report. The particle distributions are based on activity weighting of particles rather than based on the number of particles of each size. Therefore, the mass correction made in the original version is removed from the text and the calculations. Results affected by the change are updated.

Hogue, M.; Hadlock, D.; Thompson, M.; Farfan, E.

2013-11-12T23:59:59.000Z

335

Energy-Efficient Power Control in Multipath CDMA Channels via Large System Analysis  

E-Print Network (OSTI)

This paper is focused on the design and analysis of power control procedures for the uplink of multipath code-division-multiple-access (CDMA) channels based on the large system analysis (LSA). Using the tools of LSA, a new decentralized power control algorithm aimed at energy efficiency maximization and requiring very little prior information on the interference background is proposed; moreover, it is also shown that LSA can be used to predict with good accuracy the performance and operational conditions of a large network operating at the equilibrium over a multipath channel, i.e. the power, signal-to-interference-plus-noise ratio (SINR) and utility profiles across users, wherein the utility is defined as the number of bits reliably delivered to the receiver for each energy-unit used for transmission. Additionally, an LSA-based performance comparison among linear receivers is carried out in terms of achieved energy efficiency at the equilibrium. Finally, the problem of the choice of the utility-maximizing tr...

Buzzi, Stefano; Poor, H Vincent

2008-01-01T23:59:59.000Z

336

Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks  

DOE Green Energy (OSTI)

The Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks program (DE-FC26-04NT42189), commonly referred to as the AES program, focused on areas that will primarily benefit fuel economy and improve heat rejection while driving over the road. The AES program objectives were to: (1) Analyze, design, build, and test a cooling system that provided a minimum of 10 percent greater heat rejection in the same frontal area with no increase in parasitic fan load. (2) Realize fuel savings with advanced power management and acceleration assist by utilizing an integrated starter/generator (ISG) and energy storage devices. (3) Quantify the effect of aerodynamic drag due to the frontal shape mandated by the area required for the cooling system. The program effort consisted of modeling and designing components for optimum fuel efficiency, completing fabrication of necessary components, integrating these components into the chassis test bed, completing controls programming, and performance testing the system both on a chassis dynamometer and on the road. Emission control measures for heavy-duty engines have resulted in increased engine heat loads, thus introducing added parasitic engine cooling loads. Truck electrification, in the form of thermal management, offers technological solutions to mitigate or even neutralize the effects of this trend. Thermal control offers opportunities to avoid increases in cooling system frontal area and forestall reduced fuel economy brought about by additional aerodynamic vehicle drag. This project explored such thermal concepts by installing a 2007 engine that is compliant with current regulations and bears additional heat rejection associated with meeting these regulations. This newer engine replaced the 2002 engine from a previous project that generated less heat rejection. Advanced power management, utilizing a continuously optimized and controlled power flow between electric components, can offer additional fuel economy benefits to the heavy-duty trucking industry. Control software for power management brings added value to the power distribution and energy storage architecture on board a truck with electric accessories and an ISG. The research team has built upon a previous truck electrification project, formally, 'Parasitic Energy Loss Reduction and Enabling Technologies for Class 7/8 Trucks', DE-FC04-2000AL6701, where the fundamental concept of electrically-driven accessories replacing belt/gear-driven accessories was demonstrated on a Kenworth T2000 truck chassis. The electrical accessories, shown in Figure 1, were controlled to provide 'flow on demand' variable-speed operation and reduced parasitic engine loads for increased fuel economy. These accessories also provided solutions for main engine idle reduction in long haul trucks. The components and systems of the current project have been integrated into the same Kenworth T2000 truck platform. Reducing parasitic engine loading by decoupling accessory loads from the engine and driving them electrically has been a central concept of this project. Belt or gear-driven engine accessories, such as water pump, air conditioning compressor, or air compressor, are necessarily tied to the engine speed dictated by the current vehicle operating conditions. These conventional accessory pumps are sized to provide adequate flow or pressure at low idle or peak torque speeds, resulting in excess flow or pressure at cruising or rated speeds. The excess flow is diverted through a pressure-minimizing device such as a relief valve thereby expending energy to drive unnecessary and inefficient pump operation. This inefficiency causes an increased parasitic load to the engine, which leads to a loss of usable output power and decreased fuel economy. Controlling variable-speed electric motors to provide only the required flow or pressure of a particular accessory system can yield significant increases in fuel economy for a commercial vehicle. Motor loads at relatively high power levels (1-5 kW, or higher) can be efficiently provided

Larry Slone; Jeffrey Birkel

2007-10-31T23:59:59.000Z

337

Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks  

Science Conference Proceedings (OSTI)

The Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks program (DE-FC26-04NT42189), commonly referred to as the AES program, focused on areas that will primarily benefit fuel economy and improve heat rejection while driving over the road. The AES program objectives were to: (1) Analyze, design, build, and test a cooling system that provided a minimum of 10 percent greater heat rejection in the same frontal area with no increase in parasitic fan load. (2) Realize fuel savings with advanced power management and acceleration assist by utilizing an integrated starter/generator (ISG) and energy storage devices. (3) Quantify the effect of aerodynamic drag due to the frontal shape mandated by the area required for the cooling system. The program effort consisted of modeling and designing components for optimum fuel efficiency, completing fabrication of necessary components, integrating these components into the chassis test bed, completing controls programming, and performance testing the system both on a chassis dynamometer and on the road. Emission control measures for heavy-duty engines have resulted in increased engine heat loads, thus introducing added parasitic engine cooling loads. Truck electrification, in the form of thermal management, offers technological solutions to mitigate or even neutralize the effects of this trend. Thermal control offers opportunities to avoid increases in cooling system frontal area and forestall reduced fuel economy brought about by additional aerodynamic vehicle drag. This project explored such thermal concepts by installing a 2007 engine that is compliant with current regulations and bears additional heat rejection associated with meeting these regulations. This newer engine replaced the 2002 engine from a previous project that generated less heat rejection. Advanced power management, utilizing a continuously optimized and controlled power flow between electric components, can offer additional fuel economy benefits to the heavy-duty trucking industry. Control software for power management brings added value to the power distribution and energy storage architecture on board a truck with electric accessories and an ISG. The research team has built upon a previous truck electrification project, formally, 'Parasitic Energy Loss Reduction and Enabling Technologies for Class 7/8 Trucks', DE-FC04-2000AL6701, where the fundamental concept of electrically-driven accessories replacing belt/gear-driven accessories was demonstrated on a Kenworth T2000 truck chassis. The electrical accessories, shown in Figure 1, were controlled to provide 'flow on demand' variable-speed operation and reduced parasitic engine loads for increased fuel economy. These accessories also provided solutions for main engine idle reduction in long haul trucks. The components and systems of the current project have been integrated into the same Kenworth T2000 truck platform. Reducing parasitic engine loading by decoupling accessory loads from the engine and driving them electrically has been a central concept of this project. Belt or gear-driven engine accessories, such as water pump, air conditioning compressor, or air compressor, are necessarily tied to the engine speed dictated by the current vehicle operating conditions. These conventional accessory pumps are sized to provide adequate flow or pressure at low idle or peak torque speeds, resulting in excess flow or pressure at cruising or rated speeds. The excess flow is diverted through a pressure-minimizing device such as a relief valve thereby expending energy to drive unnecessary and inefficient pump operation. This inefficiency causes an increased parasitic load to the engine, which leads to a loss of usable output power and decreased fuel economy. Controlling variable-speed electric motors to provide only the required flow or pressure of a particular accessory system can yield significant increases in fuel economy for a commercial vehicle. Motor loads at relatively high power levels (1-5 kW, or higher) can be efficiently provided

Larry Slone; Jeffrey Birkel

2007-10-31T23:59:59.000Z

338

Experimental evidence for a liquid-gas phase transition in nuclear systems  

SciTech Connect

At certain combinations of temperature and density, nuclear matter may exist as a liquid-gas mixture exhibiting phase instabilities, a characteristic signature of which may be found in the emission of intermediate-mass fragments in nuclear collisions. The present analysis of fragment distributions from proton-- and heavy-ion--induced reactions, in the framework of a theory of condensation, is suggestive of the occurrence of such phase transitions with a critical exponent kapprox.1.7 and a critical temperature T/sub C/approx.12 MeV.

Panagiotou, A.D.; Curtin, M.W.; Toki, H.; Scott, D.K.; Siemens, P.J.

1984-02-13T23:59:59.000Z

339

Federal Transit Administration-National Transit Database (NTD) | Open  

Open Energy Info (EERE)

Federal Transit Administration-National Transit Database (NTD) Federal Transit Administration-National Transit Database (NTD) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Federal Transit Administration-National Transit Database (NTD) Agency/Company /Organization: Federal Transit Administration Sector: Energy Focus Area: Transportation Resource Type: Dataset User Interface: Website Website: www.ntdprogram.gov/ntdprogram/ Cost: Free Language: English Federal Transit Administration-National Transit Database (NTD) Screenshot References: National Transit Database[1] "The NTD was established by Congress to be the Nation's primary source for information and statistics on the transit systems of the United States. Recipients or beneficiaries of grants from the Federal Transit Administration (FTA) under the Urbanized Area Formula Program (§5307) or

340

Current Building Energy Codes: Using the Process to Advance Energy Efficient Systems  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

12 12 NREL / Build America Stakeholders Meeting Presented by David Karmol, VP, Federal & External Affairs  The purpose of this presentation is to provide information on ICC model codes that impact the design and construction of buildings, and tactics to allow Building America advances to be incorporated into the model code and/or recognized by building code officials  The expected outcome is an ability to expand the reach of Build America innovations, by using available resources to mainstream new energy efficiency systems into building practices nationwide 2 3  Will apply to traditional commercial and high-performance buildings.  Consistent and coordinated with the ICC family of Codes & Standards.  Applicable to the construction of

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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341

Catalytic reactive separation system for energy-efficient production of cumene  

DOE Patents (OSTI)

The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

Buelna, Genoveva (Nuevo Laredo, MX); Nenoff, Tina M. (Albuquerque, NM)

2009-07-28T23:59:59.000Z

342

Evaluating Interventions in the U.S. Electricity System: Assessments of Energy Efficiency, Renewable Energy,  

E-Print Network (OSTI)

of Energy Efficiency, Renewable Energy, and Small-Scale Cogeneration from electricity generation. Renewable energy, energy efficiency, and energy, where performance is measured relative to three objectives: energy production

343

The Transition from the Present Radar Dissemination System to the NEXRAD Information Dissemination Service (NIDS)  

Science Conference Proceedings (OSTI)

The National Weather Service (NWS) will begin replacing its current system of weather radars with Next Generation Weather Radars (NEXRAD) in late 1990. Presented is an overview of previous and current systems, and the replacement NEXRAD ...

Vico E. Baer

1991-01-01T23:59:59.000Z

344

Toward green systems for cleanrooms: Energy efficient fan-filter units  

E-Print Network (OSTI)

information to users and designers to make informed decisions such as selecting more energy efficient models; Market

Jeng, Ming-Shan; Xu, Tengfang; Lan, Chao-Ho

2004-01-01T23:59:59.000Z

345

Efficient model-based leak detection in boiler steam-water systems Xi Sun, Tongwen Chen *, Horacio J. Marquez  

E-Print Network (OSTI)

Efficient model-based leak detection in boiler steam-water systems Xi Sun, Tongwen Chen *, Horacio detection in boiler steam-water systems. The algorithm has been tested using real industrial data from Syncrude Canada, and has proven to be effective in detection of boiler tube or steam leaks; proper

Marquez, Horacio J.

346

PLANET-PLANET ECLIPSE AND THE ROSSITER-McLAUGHLIN EFFECT OF A MULTIPLE TRANSITING SYSTEM: JOINT ANALYSIS OF THE SUBARU SPECTROSCOPY AND THE KEPLER PHOTOMETRY  

Science Conference Proceedings (OSTI)

We report a joint analysis of the Rossiter-McLaughlin (RM) effect with Subaru and the Kepler photometry for the Kepler Object of Interest (KOI) 94 system. The system is comprised of four transiting planet candidates with orbital periods of 22.3 (KOI-94.01), 10.4 (KOI-94.02), 54.3 (KOI-94.03), and 3.7 (KOI-94.04) days from the Kepler photometry. We performed the radial velocity (RV) measurement of the system with the Subaru 8.2 m telescope on UT 2012 August 10, covering a complete transit of KOI-94.01 for {approx}6.7 hr. The resulting RV variation due to the RM effect spectroscopically confirms that KOI-94.01 is indeed the transiting planet and implies that its orbital axis is well aligned with the stellar spin axis; the projected spin-orbit angle {lambda} is estimated as -6{sup +13}{sub -11} deg. This is the first measurement of the RM effect for a multiple transiting system. Remarkably, the archived Kepler light curve around BJD = 2455211.5 (date in UT 2010 January 14/15) indicates a 'double-transit' event of KOI-94.01 and KOI-94.03, in which the two planets transit the stellar disk simultaneously. Moreover, the two planets partially overlap with each other, and exhibit a 'planet-planet eclipse' around the transit center. This provides a rare opportunity to put tight constraints on the configuration of the two transiting planets by joint analysis with our Subaru RM measurement. Indeed, we find that the projected mutual inclination of KOI-94.01 and KOI-94.03 is estimated to be {delta} = -1.{sup 0}15 {+-} 0.{sup 0}55. Implications for the migration model of multiple planet systems are also discussed.

Hirano, Teruyuki; Masuda, Kento; Suto, Yasushi [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Narita, Norio; Takahashi, Yasuhiro H.; Takeda, Yoichi; Aoki, Wako; Tamura, Motohide [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Sato, Bun'ei, E-mail: hirano@utap.phys.s.u-tokyo.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)

2012-11-10T23:59:59.000Z

347

Transition Probabilities in {sup 134}Pr: A Test for Chirality in Nuclear Systems  

SciTech Connect

Exited states in {sup 134}Pr were populated in the fusion-evaporation reaction {sup 119}Sn({sup 19}F,4n){sup 134}Pr. Recoil distance Doppler-shift and Doppler-shift attenuation measurements using the Euroball spectrometer, in conjunction with the inner Bismuth Germanate ball and the Cologne plunger, were performed at beam energies of 87 MeV and 83 MeV, respectively. Reduced transition probabilities in {sup 134}Pr are compared to the predictions of the two quasiparticle+triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in {sup 134}Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in {sup 134}Pr can be supported.

Tonev, D. [Laboratori Nazionali di Legnaro, INFN, I-35020 Legnaro (Italy); Institute for Nuclear Research and Nuclear Energy, BAS, 1784 Sofia (Bulgaria); De Angelis, G.; Gadea, A.; Marginean, N.; Napoli, D.R.; Prete, G. [Laboratori Nazionali di Legnaro, INFN, I-35020 Legnaro (Italy); Petkov, P. [Institute for Nuclear Research and Nuclear Energy, BAS, 1784 Sofia (Bulgaria); Dewald, A.; Pejovic, P.; Fitzler, A.; Moeller, O.; Zell, K.O. [Institut fuer Kernphysik der Universitaet zu Koeln, D-50937 Cologne (Germany); Brant, S. [Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Frauendorf, S. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Balabanski, D.L. [Institute for Nuclear Research and Nuclear Energy, BAS, 1784 Sofia (Bulgaria); Dipartimento di Fisica, Universita di Camerino and INFN Perugia, I-62032 Camerino (Italy); Bazzacco, D.; Lenzi, S.; Lunardi, S. [Dipartimento di Fisica, Universita and INFN Sezione di Padova, I-35131 Padova (Italy); Bednarczyk, P.; Curien, D. [Institut de Recherches Subatomiques, Boite Postale 28 F-67037, Strasbourg (France)] (and others)

2006-02-10T23:59:59.000Z

348

Steam systems in industry: Energy use and energy efficiency improvement potentials  

SciTech Connect

Steam systems are a part of almost every major industrial process today. Thirty-seven percent of the fossil fuel burned in US industry is burned to produce steam. In this paper we will establish baseline energy consumption for steam systems. Based on a detailed analysis of boiler energy use we estimate current energy use in boilers in U.S. industry at 6.1 Quads (6.4 EJ), emitting almost 66 MtC in CO{sub 2} emissions. We will discuss fuels used and boiler size distribution. We also describe potential savings measures, and estimate the economic energy savings potential in U.S. industry (i.e. having payback period of 3 years or less). We estimate the nationwide economic potential, based on the evaluation of 16 individual measures in steam generation and distribution. The analysis excludes the efficient use of steam and increased heat recovery. Based on the analysis we estimate the economic potential at 18-20% of total boiler energy use, resulting in energy savings approximately 1120-1190 TBtu ( 1180-1260 PJ). This results in a reduction of CO{sub 2} emissions equivalent to 12-13 MtC.

Einstein, Dan; Worrell, Ernst; Khrushch, Marta

2001-07-22T23:59:59.000Z

349

Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation  

SciTech Connect

Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.

Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.

2012-05-01T23:59:59.000Z

350

EVALUATION OF TRANSITIONS FOR TESTING AGRICULTURAL VENTILATION FANS WITH THE FAN ASSESSMENT NUMERATION SYSTEM (FANS).  

E-Print Network (OSTI)

??The Fan Assessment Numeration System (FANS) is an improved air velocity traverse method for measuring in situ fan performance. The FANS has been widely used,… (more)

Lopes, Igor Moreira

2012-01-01T23:59:59.000Z

351

Study of Energy and Demand Savings on a High Efficiency Hydraulic Pump System with Infinite Turn Down Technology (ITDT)  

E-Print Network (OSTI)

Detailed field measurement and verification of electrical energy (kWh) and demand (kW) savings is conducted on an injection molding machine used in typical plastic manufacturing facility retrofitted with a high efficiency hydraulic pump system. Significant energy usage and demand savings are verified for the retrofitted injection molding machine. The savings are realized by electronically attenuating the torque of a positive displacement pump irrespective of the volumetric flow required by the cycle. With help of a power analyzer, power quality issues are addressed. Some voltage distortion was observed due to the harmonic currents introduced by the control algorithm of the high efficiency hydraulic system. A comparative study of electrical energy and demand savings between an injection molding machine retrofitted with the high efficiency hydraulic pump system or variable frequency drive will also be presented.

Sfeir, R. A.; Kanungo, A.; Liou, S.

2005-01-01T23:59:59.000Z

352

A study of lead-acid battery efficiency near top-of-charge and the impact on PV system design  

SciTech Connect

Knowledge of the charge efficiency of lead-acid batteries near top-of-charge is important to the design of small photovoltaic systems. In order to know how much energy is required from the photovoltaic array in order to accomplish the task of meeting load, including periodic full battery charge, a detailed knowledge of the battery charging efficiency as a function of state of charge is required, particularly in the high state-of-charge regime, as photovoltaic systems are typically designed to operate in the upper 20 to 30% of battery state-of-charge. This paper presents the results of a process for determining battery charging efficiency near top-of-charge and discusses the impact of these findings on the design of small PV systems.

Stevens, J.W.; Corey, G.P.

1996-07-01T23:59:59.000Z

353

Efficient electric motor systems for industry. Report on roundtable discussions of market problems and ways to overcome them  

Science Conference Proceedings (OSTI)

Improving the efficiency of electric motor systems is one of the best energy-saving opportunities for the United States. The Department of Energy (DOE) Office of Industrial Technologies estimates that by the year 2010 in the industrial sector, the opportunities for savings from improved efficiency in electric motor systems could be roughly as follows: 240 billion kilowatthours per year. $13 billion per year from US industry`s energy bill. Up to 50,000 megawatts in new powerplant capacity avoided. Up to 44 million metric tons of carbon-equivalent emissions mitigated per year, corresponding to 3 percent of present US emissions. Recognizing the benefits of this significant opportunity for energy savings, DOE has targeted improvements in the efficiency of electric motor systems as a key initiative in the effort to promote flexibility and efficiency in the way electricity is produced and used. Efficient electric motor systems will help the United States reach its national goals for energy savings and greenhouse gas emission reductions.

Not Available

1993-11-01T23:59:59.000Z

354

Efficient energy transfer in light-harvesting systems, III: The influence of the eighth bacteriochlorophyll on the dynamics and efficiency in FMO  

E-Print Network (OSTI)

The most recent crystal structure of the Fenna-Matthews-Olson (FMO) protein complex indicates that each subunit contains an additional eighth chromophore. It has been proposed that this extra site functions as a link between the chlorosome antenna complex and the remaining seven chromophores in FMO [Schmidt am Busch et al, J. Phys. Chem. Lett., {\\bf 2}, 93 (2011)]. Here, we investigate the implications of this scenario through numerical calculations with the generalized Bloch-Redfield (GBR) equation and the non-interacting blip approximation (NIBA). Three key insights into the population dynamics and energy transfer efficiency in FMO are provided. First, it is shown that the oscillations that are often observed in the population relaxation of the dimer composed of sites one and two may be completely suppressed in the eight site model. The presence of the coherent oscillations is shown to depend upon the particular initial preparation of the dimer state. Secondly it is demonstrated that while the presence of the eighth chromophore does not cause a dramatic change in the energy transfer efficiency, it does however lead to a dominant energy transfer pathway which can be characterized by an effective three site system arranged in an equally spaced downhill configuration. Such a configuration leads to an optimal value of the site energy of the eighth chromophore which is shown to be near to its suggested value. Finally we confirm that the energy transfer process in the eight site FMO complex remains efficient and robust. The optimal values of the bath parameters are computed and shown to be closer to the experimentally fitted values than those calculated previously for the seven site system.

Jeremy Moix; Jianlan Wu; Pengfei Huo; David Coker; Jianshu Cao

2011-09-14T23:59:59.000Z

355

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-Print Network (OSTI)

energy conversion systems ..on thermal energy conversion systems As energy demandsefficient energy conversion in power systems," in Thermal

Ho, Tony

2012-01-01T23:59:59.000Z

356

Applied fractionalization : quantum phases and phase transitions of strongly interacting systems  

E-Print Network (OSTI)

Strongly correlated systems present interesting challenges in condensed matter physics. On the one hand, the theoretical work in the last two decades suggests that strong interactions may lead to new phases and phase ...

Grover, Tarun, Ph. D. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

357

Automated-Manual Transitions: Human Capabilities and Adaptive Cruise Control  

E-Print Network (OSTI)

TRANSIT AND HIGHWAYS Automated-Manual Transitions: HumanOF CALIFORNIA, BERKELEY Automated-Manual Transitions: HumanSuch systems will supplant manual controls during certain

Barton, Joseph E.; Cohn, Theodore E.; Nguyen, Khoi M.; Nguyen, Tieuvi; Toyofuku, Natsuko

2004-01-01T23:59:59.000Z

358

Generic Mechanism of Optimal Energy Transfer Efficiency: A Scaling Theory of the Mean First Passage Time in Exciton Systems  

E-Print Network (OSTI)

An asymptotic scaling theory is presented using the conceptual basis of trapping-free subspace (i.e., orthogonal subspace) to establish the generic mechanism of optimal efficiency of excitation energy transfer (EET) in light-harvesting systems. Analogous to Kramers' turnover in classical rate theory, the enhanced efficiency in the weak damping limit and the suppressed efficiency in the strong damping limit define two asymptotic scaling regimes, which are interpolated to predict the functional form of optimal efficiency of the trapping-free subspace. In the presence of static disorder, the scaling law of transfer time with respect to dephasing rate changes from linear to square root, suggesting a weaker dependence on the environment. Though formulated in the context of EET, the analysis and conclusions apply in general to open quantum processes, including electron transfer, fluorescence emission, and heat conduction.

Wu, Jianlan; Silbey, Robert J

2013-01-01T23:59:59.000Z

359

Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines  

SciTech Connect

The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to provide experimental combustion data of our target fuels at gas turbine conditions. Based on an initial assessment of premixer design requirements and challenges, the most promising sub-scale premixer concepts were evaluated both experimentally and computationally. After comprehensive screening tests, two best performing concepts were scaled up for further development. High pressure single nozzle tests were performed with the scaled premixer concepts at target gas turbine conditions with opportunity fuels. Single-digit NOx emissions were demonstrated for syngas fuels. Plasma-assisted pilot technology was demonstrated to enhance ignition capability and provide additional flame stability margin to a standard premixing fuel nozzle. However, the impact of plasma on NOx emissions was observed to be unacceptable given the goals of this program and difficult to avoid.

Venkatesan, Krishna

2011-11-30T23:59:59.000Z

360

Reducing Barriers To The Use of High-Efficiency Lighting Systems  

Science Conference Proceedings (OSTI)

With funding from the U.S. Department of Energy (DOE), the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute completed the four-year research project, Reducing Barriers to the Use of High-Efficiency Lighting Systems. The initial objectives were: (1) identifying barriers to widespread penetration of lighting controls in commercial/industrial (C/I) applications that employ fluorescent lamp technologies, and (2) making recommendations to overcome these barriers. The addition of a fourth year expanded the original project objectives to include an examination of the impact on fluorescent lamps from dimming utilizing different lamp electrode heating and dimming ratios. The scope of the project was narrowed to identify barriers to the penetration of lighting controls into commercial-industrial (C/I) applications that employ fluorescent lamp technologies, and to recommend means for overcoming these barriers. Working with lighting manufacturers, specifiers, and installers, the project identified technological and marketing barriers to the widespread use of lighting controls, specifically automatic-off controls, occupancy sensors, photosensors, dimming systems, communication protocols and load-shedding ballasts. The primary barriers identified include cost effectiveness of lighting controls to the building owner, lack of standard communication protocols to allow different part of the control system to communicate effectively, and installation and commissioning issues. Overcoming the identified barriers requires lighting control products on the market to achieve three main goals: (1) Achieve sufficient functionality to meet the key requirements of their main market. (2) Allow significant cost reduction compared to current market standard systems. Cost should consider: hardware capital cost including wiring, design time required by the specifier and the control system manufacturer, installation time required by the electrician, and commissioning time and remedial time required by the electrician and end user. (3) Minimize ongoing perceived overhead costs and inconvenience to the end user, or in other words, systems should be simple to understand and use. In addition, we believe that no lighting controls solution is effective or acceptable unless it contributes to, or does not compromise, the following goals: (1) Productivity--Planning, installation, commissioning, maintenance, and use of controls should not decrease business productivity; (2) Energy savings--Lighting controls should save significant amounts of energy and money in relation to the expense involved in using them (acceptable payback period); and/or (3) Reduced power demand--Society as a whole should benefit from the lowered demand for expensive power and for more natural resources. Discussions of technology barriers and developments are insufficient by themselves to achieve higher penetration of lighting controls in the market place. Technology transfer efforts must play a key role in gaining market acceptance. The LRC developed a technology transfer model to better understand what actions are required and by whom to move any technology toward full market acceptance.

Peter Morante

2005-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Efficient energy transfer in light-harvesting systems, I: optimal temperature, reorganization energy, and spatial-temporal correlations  

E-Print Network (OSTI)

Understanding the mechanisms of efficient and robust energy transfer in light-harvesting systems provides new insights for the optimal design of artificial systems. In this paper, we use the Fenna-Matthews-Olson (FMO) protein complex and phycocyanin 645 (PC 645) to explore the general dependence on physical parameters that help maximize the efficiency and maintain its stability. With the Haken-Strobl model, the maximal energy transfer efficiency (ETE) is achieved under an intermediate optimal value of dephasing rate. Guided by the insight, we use the generalized Bloch-Redfield (GBR) equation approach to correctly describe dissipative exciton dynamics and find that maximal ETE can be achieved under various physical conditions, including temperature, reorganization energy, and spatial-temporal correlations in noise. We also identify regimes of reorganization energy where the ETE changes monotonically with temperature or spatial correlation and therefore cannot be optimized with respect to these two variables.

Wu, Jianlan; Shen, Young; Cao, Jianshu; Silbey, Robert J

2010-01-01T23:59:59.000Z

362

Techno-Economic Feasibility of Highly Efficient Cost-Effective Thermoelectric-SOFC Hybrid Power Generation Systems  

DOE Green Energy (OSTI)

Solid oxide fuel cell (SOFC) systems have the potential to generate exhaust gas streams of high temperature, ranging from 400 to 800 C. These high temperature gas streams can be used for additional power generation with bottoming cycle technologies to achieve higher system power efficiency. One of the potential candidate bottoming cycles is power generation by means of thermoelectric (TE) devices, which have the inherent advantages of low noise, low maintenance and long life. This study was to analyze the feasibility of combining coal gas based SOFC and TE through system performance and cost techno-economic modeling in the context of multi-MW power plants, with 200 kW SOFC-TE module as building blocks. System and component concepts were generated for combining SOFC and TE covering electro-thermo-chemical system integration, power conditioning system (PCS) and component designs. SOFC cost and performance models previously developed at United Technologies Research Center were modified and used in overall system analysis. The TE model was validated and provided by BSST. The optimum system in terms of energy conversion efficiency was found to be a pressurized SOFC-TE, with system efficiency of 65.3% and cost of $390/kW of manufacturing cost. The pressurization ratio was approximately 4 and the assumed ZT of the TE was 2.5. System and component specifications were generated based on the modeling study. The major technology and cost barriers for maturing the system include pressurized SOFC stack using coal gas, the high temperature recycle blowers, and system control design. Finally, a 4-step development roadmap is proposed for future technology development, the first step being a 1 kW proof-of-concept demonstration unit.

Jifeng Zhang; Jean Yamanis

2007-09-30T23:59:59.000Z

363

Creating systems that effectively convert energy, such as efficient solar cells and electrochemical batteries, has been a  

E-Print Network (OSTI)

SEMTE abstract Creating systems that effectively convert energy, such as efficient solar cells stimuli, the solar energy from sunlight, and the mechanical motion is commonplace, indeed fundamental and electrochemical batteries, has been a longstanding scientific pursuit, especially given the global energy

Reisslein, Martin

364

HiPPIS: an online P2P system for efficient lookups on d-dimensional hierarchies  

Science Conference Proceedings (OSTI)

In this paper we describe HiPPIS, a system that enables efficient storage and on-line querying of multidimensional data organized into concept hierarchies and dispersed over a network. Our scheme utilizes an adaptive algorithm that automatically ... Keywords: concept hierarchies, data warehousing, distributed hash table

Katerina Doka; Dimitrios Tsoumakos; Nectarios Koziris

2008-10-01T23:59:59.000Z

365

Threshold jumping and wrap-around scan techniques toward efficient tag identification in high density RFID systems  

Science Conference Proceedings (OSTI)

With the emergence of wireless RFID technologies, the problem of Anti-Collision has been arousing attention and instigated researchers to propose different heuristic algorithms for advancing RFID systems operated in more efficient manner. However, there ... Keywords: Query tree, Tag anti-collision, Threshold jumping, Wrap-around scan

Ching-Hsien Hsu; Han-Chieh Chao; Jong Hyuk Park

2011-09-01T23:59:59.000Z

366

Systems Analyses of Advanced Brayton Cycles For High Efficiency Zero Emission Plants  

Science Conference Proceedings (OSTI)

Table 1 shows that the systems efficiency, coal (HHV) to power, is 35%. Table 2 summarizes the auxiliary power consumption within the plant. Thermoflex was used to simulate the power block and Aspen Plus the balance of plant. The overall block flow diagram is presented in Figure A1.3-1 and the key unit process flow diagrams are shown in subsequent figures. Stream data are given in Table A1.3-1. Equipment function specifications are provided in Tables A1.3-2 through 17. The overall plant scheme consists of a cryogenic air separation unit supplying 95% purity O{sub 2} to GE type high pressure (HP) total quench gasifiers. The raw gas after scrubbing is treated in a sour shift unit to react the CO with H{sub 2}O to form H{sub 2} and CO{sub 2}. The gas is further treated to remove Hg in a sulfided activated carbon bed. The syngas is desulfurized and decarbonized in a Selexol acid gas removal unit and the decarbonized syngas after humidification and preheat is fired in GE 7H type steam cooled gas turbines. Intermediate pressure (IP) N{sub 2} from the ASU is also supplied to the combustors of the gas turbines as additional diluent for NOx control. A portion of the air required by the ASU is extracted from the gas turbines. The plant consists of the following major process units: (1) Air Separation Unit (ASU); (2) Gasification Unit; (3) CO Shift/Low Temperature Gas Cooling (LTGC) Unit; (4) Acid Gas Removal Unit (AGR) Unit; (5) Fuel Gas Humidification Unit; (6) Carbon Dioxide Compression/Dehydration Unit; (7) Claus Sulfur Recovery/Tail Gas Treating Unit (SRU/TGTU); and (8) Power Block.

A. D. Rao; J. Francuz; H. Liao; A. Verma; G. S. Samuelsen

2006-11-01T23:59:59.000Z

367

Negative heat capacities and first order phase transitions in nuclei and other mesoscopic systems  

E-Print Network (OSTI)

The origin of predicted and observed anomalies in caloric curves of nuclei and other mesoscopic systems is investigated. It is shown that a straightforward thermodynamical treatment of an evaporating liquid drop leads to a backbending in the caloric curve and to negative specific heats in the two phase coexistence region. The cause is found not in the generation of additional surface, but in the progressive reduction of the drop's radius, and surface, with evaporation.

L. G. Moretto; J. B. Elliott; L. Phair; G. J. Wozniak

2000-12-11T23:59:59.000Z

368

Study of the design Method of an Efficient Ground Source Heat Pump Thermal Source System in a Cold Area  

E-Print Network (OSTI)

The ground source heat pump (GSHP) system-an energy efficiency and environment friendly system-is becoming popular in many parts of China. However, an imbalance usually exists between the annual heat extracted from and rejected to the ground due to the different heating and cooling load of a building, which will consistently deteriorate the heat pump efficiency leading even to the breakdown of the heat pump. This paper brings forward a design method of adding supplemental heat rejection equipment, a cooling tower, in the system to solve the problem in a cold area. Taking an office building in Beijing as an example, the authors simulate the GSHP system with two different connection methods between the cooling tower and vertical buried-pipe heat exchangers (in series and in parallel) using TRNSYS simulation software, and put forward several design schemes that can ensure the whole system continually operates with high efficiency. This also makes it possible to perform a more detailed economic optimization of the GSHP-based system in the future.

Shu, H.; Duanmu, L.; Hua, R.; Zou, Y.; Du, G.

2006-01-01T23:59:59.000Z

369

Financial analysis of energy-efficient façade systems for application in commercial office developments  

E-Print Network (OSTI)

Advocates for sustainable development have been campaigning for the implementation of green features in developments. New and high-technology energy-efficient technologies, such as photovoltaic cells and double skin fac?ades, ...

Dee, Rocelyn Sy, 1976-

2002-01-01T23:59:59.000Z

370

A systems engineering methodology for fuel efficiency and its application to a tactical wheeled vehicle demonstrator  

E-Print Network (OSTI)

The U.S. Department of Defense faces growing fuel demand, resulting in increasing costs and compromised operational capability. In response to this issue, the Fuel Efficient Ground Vehicle Demonstrator (FED) program was ...

Luskin, Paul (Paul L.)

2010-01-01T23:59:59.000Z

371

ASE/CAGI Meeting about Compressors and Compressed Air System Efficiency  

Energy.gov (U.S. Department of Energy (DOE))

On April 25, 2013, several representatives of energy efficiency advocacy organizations met with staff and members of the Compressed Air and Gas Institute (CAGI) along with some compressed air...

372

Ecological and Economical efficient Heating and Cooling by innovative Gas Motor Heat Pump Systems and Solutions  

E-Print Network (OSTI)

options ·Universal application as an Air-Air System (VRF), Air-Water System or combined as a Mixed System application options · Option 1: Air-Air System (VRF) #12;· Option 2: Air-Air System (HVAC System) Gas Heat

Oak Ridge National Laboratory

373

Development and Demonstration of a New Generation High Efficiency 10kW Stationary Fuel Cell System  

SciTech Connect

The overall project objective is to develop and demonstrate a polymer electrolyte membrane fuel cell combined heat and power (PEMFC CHP) system that provides the foundation for commercial, mass produced units which achieve over 40% electrical efficiency (fuel to electric conversion) from 50-100% load, greater than 70% overall efficiency (fuel to electric energy + usable waste heat energy conversion), have the potential to achieve 40,000 hours durability on all major process components, and can be produced in high volumes at under $400/kW (revised to $750/kW per 2011 DOE estimates) capital cost.

Howell, Thomas Russell

2013-04-30T23:59:59.000Z

374

Integrated system for control and monitoring in real time of efficient electrical and thermal energy production  

Science Conference Proceedings (OSTI)

The integrated monitoring and driving system is made of main distributed components: - first level:_one or two computers placed in the control room which monitors the thermal and electrical processes based on the datas provided by the second level via ... Keywords: cogenerative gas power plant, control of distributed parameter systems, distribution management system, electric power systems, optimization, process control, real time systems, simulation

Ion Miciu; Florin Hartescu

2008-08-01T23:59:59.000Z

375

Phase II Final Project Report SBIR Project: "A High Efficiency PV to Hydrogen Energy System"  

Science Conference Proceedings (OSTI)

The innovative research conducted for this project contributed greatly to the understanding of generating low-cost hydrogen from solar energy. The project’s research identified two highly leveraging and complementary pathways. The first pathway is to dramatically increase the efficiency of converting sunlight into electricity. Improving solar electric conversion efficiency directly increases hydrogen production. This project produced a world record efficiency for silicon solar cells and contributed to another world record efficiency for a solar concentrator module using multijunction solar cells. The project’s literature review identified a second pathway in which wasted heat from the solar concentration process augments the electrolysis process generating hydrogen. One way to do this is to use a “heat mirror” that reflects the heat-producing infrared and transmits the visible spectrum to the solar cells; this also increases solar cell conversion efficiency. An economic analysis of this concept confirms that, if long-term concentrator photovoltaic (CPV) and solid-oxide electrolyzer cost goals can be achieved, hydrogen will be produced from solar energy cheaper than the cost of gasoline. The potential public benefits from this project are significant. The project has identified a potential energy source for the nation’s future electricity and transportation needs that is entirely “home grown” and carbon free. As CPV enter the nation’s utility markets, the opportunity for this approach to be successful is greatly increased. Amonix strongly recommends further exploration of this project’s findings.

Slade, A; Turner, J; Stone, K; McConnell, R

2008-09-02T23:59:59.000Z

376

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-Print Network (OSTI)

reclamation and solar thermal energy," Energy [accepted]. [and M Dennis, "Solar thermal energy systems in Australia,"and M Dennis, "Solar thermal energy systems in Australia,"

Ho, Tony

2012-01-01T23:59:59.000Z

377

You need this done by when '': Increasing your efficiency with the SAS reg sign system  

SciTech Connect

The SAS Institute publication -- SAS Programming Tips: A Guide to Efficient SAS Processing defines efficiency as obtaining more results from fewer computer or human resources.'' While this publication contains many very useful tips, it seems to concentrate mostly on computer efficiency. This paper will focus on ways of increasing your efficiency in developing, writing, and debugging SAS programs, i.e. increasing human efficiency. In my job as a consulting statistician, my programs are usually one-run programs. That is, I develop and test a program, then I run them once to get the results I need, and the program is typically never used again. Even for multiple run jobs, the greatest expense by far is the time used to develop a program, and any CPU/hardware expense'' is relatively insignificant. I believe that this is true for most SAS system users and that not enough attention has been given to this aspect of cost''. While most of these tips and techniques were developed under the PC platform, nearly all are applicable and useful under all SAS supported platforms. Some of the tips the experienced SAS programmer may already be familiar with, but many should be new and useful to both novice and veteran users.

DeHaan, M.S.

1992-01-01T23:59:59.000Z

378

How Does Your Data Center Measure Up? Energy Efficiency Metrics and Benchmarks for Data Center Infrastructure Systems  

SciTech Connect

Data centers are among the most energy intensive types of facilities, and they are growing dramatically in terms of size and intensity [EPA 2007]. As a result, in the last few years there has been increasing interest from stakeholders - ranging from data center managers to policy makers - to improve the energy efficiency of data centers, and there are several industry and government organizations that have developed tools, guidelines, and training programs. There are many opportunities to reduce energy use in data centers and benchmarking studies reveal a wide range of efficiency practices. Data center operators may not be aware of how efficient their facility may be relative to their peers, even for the same levels of service. Benchmarking is an effective way to compare one facility to another, and also to track the performance of a given facility over time. Toward that end, this article presents the key metrics that facility managers can use to assess, track, and manage the efficiency of the infrastructure systems in data centers, and thereby identify potential efficiency actions. Most of the benchmarking data presented in this article are drawn from the data center benchmarking database at Lawrence Berkeley National Laboratory (LBNL). The database was developed from studies commissioned by the California Energy Commission, Pacific Gas and Electric Co., the U.S. Department of Energy and the New York State Energy Research and Development Authority.

Mathew, Paul; Greenberg, Steve; Ganguly, Srirupa; Sartor, Dale; Tschudi, William

2009-04-01T23:59:59.000Z

379

Investigating potential light-duty efficiency improvements through simulation of turbo-compounding and waste-heat recovery systems  

Science Conference Proceedings (OSTI)

Modern diesel engines used in light-duty transportation applications have peak brake thermal efficiencies in the range of 40-42% for high-load operation with substantially lower efficiencies at realistic road-load conditions. Thermodynamic energy and exergy analysis reveals that the largest losses from these engines are due to combustion irreversibility and heat loss to the coolant, through the exhaust, and by direct convection and radiation to the environment. Substantial improvement in overall engine efficiency requires reducing or recovering these losses. Unfortunately, much of the heat transfer either occurs at relatively low temperatures resulting in large entropy generation (such as in the air-charge cooler), is transferred to low-exergy flow streams (such as the oil and engine coolant), or is radiated or convected directly to the environment. While there are significant opportunities for recovery from the exhaust and EGR cooler for heavy-duty applications, achieving similar benefits for light-duty applications is complicated by transient, low-load operation at typical driving conditions and competition with the turbocharger and aftertreatment system for the limited thermal resources. We have developed an organic Rankine cycle model using GT-Suite to investigate the potential for efficiency improvement through waste-heat recovery from the exhaust and EGR cooler of a light-duty diesel engine. The model is used to examine the effects of efficiency-improvement strategies such as cylinder deactivation, use of advanced materials and improved insulation to limit ambient heat loss, and turbo-compounding on the steady-state performance of the ORC system and the availability of thermal energy for downstream aftertreatment systems. Results from transient drive-cycle simulations are also presented, and we discuss strategies to address operational difficulties associated with transient drive cycles and balancing the thermal requirements of waste-heat recovery, turbocharging or turbo-compounding, and exhaust aftertreatment.

Edwards, Kevin Dean [ORNL; Wagner, Robert M [ORNL; Briggs, Thomas E [ORNL

2010-01-01T23:59:59.000Z

380

Clean air program: Design guidelines for bus transit systems using liquefied petroleum gas (LPG) as an alternative fuel. Final report, July 1995-April 1996  

Science Conference Proceedings (OSTI)

The Federal Transit Administration (FTA) has initiated the development of `Design Guidelines for Bus Transit Systems Using Alternative Fuels.` This report provides design guidelines for the safe uses of Liquefied Petroleum Gas (LPG). It forms a part of the series of individual monographs being published by the FTA on (the guidelines for the safe use of) Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquefied Petroleum Gas (LPG) and alcohol fuels (Methanol and Ethanol). Each report in this series describes for the subject fuel the important fuel properties, guidelines for the design and operation of bus fueling, storage and maintenance facilities, issues on personnel training and emergency preparedness.

Raj, P.K.; Hathaway, W.T.; Kangas, R.

1996-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Best Practices for Energy Efficient Cleanrooms: Control of Chilled Water System  

E-Print Network (OSTI)

for cleanrooms and their adjacent spaces. Chillers 39% Cooling Towers 7% Pumps 17% MUAH + RCU Fans 9% Hot Water;chilled water pumps, secondary loop chilled water pumps, condenser water pumps, and cooling towers for water-cooled chillers. While nominal energy efficiency ratings of individual component influence

382

Using information systems to improve energy efficiency: Do smart meters make a difference?  

Science Conference Proceedings (OSTI)

The large-scale generation of electricity is a major contributor to increasing levels of greenhouse gas emissions, putting pressure on the industry to reduce its environmental impacts. Electricity utility companies are looking to two strategies to help ... Keywords: Demand-side management, Energy efficiency, Energy informatics, Green IS, Information processing, Information waste, Smart grid, Sustainability

Jacqueline Corbett

2013-11-01T23:59:59.000Z

383

A national program for energy-efficient mortgages and home energy rating systems: A blueprint for action  

SciTech Connect

This Review Draft reports findings and recommendations of the National Collaborative on Home Energy Rating Systems and Mortgage Incentives for Energy Efficiency. The US Department of Energy, in cooperation with the US Department of Housing and Urban Development, formed this National Collaborative as a National Energy Strategy initiative. Participating in the Collaborative were representatives of the primary and secondary mortgage markets, builder and remodeler organizations, real estate and appraiser associations, the home energy rating system industry, utility associations, consumer and public interest groups, state and local government interest groups, and environmental organizations. The Collaborative's purpose was to develop a voluntary national program encouraging energy efficiency in homes through mortgage incentives linked to home energy ratings.

1992-03-01T23:59:59.000Z

384

A national program for energy-efficient mortgages and home energy rating systems: A blueprint for action. Review draft  

SciTech Connect

This Review Draft reports findings and recommendations of the National Collaborative on Home Energy Rating Systems and Mortgage Incentives for Energy Efficiency. The US Department of Energy, in cooperation with the US Department of Housing and Urban Development, formed this National Collaborative as a National Energy Strategy initiative. Participating in the Collaborative were representatives of the primary and secondary mortgage markets, builder and remodeler organizations, real estate and appraiser associations, the home energy rating system industry, utility associations, consumer and public interest groups, state and local government interest groups, and environmental organizations. The Collaborative`s purpose was to develop a voluntary national program encouraging energy efficiency in homes through mortgage incentives linked to home energy ratings.

1992-03-01T23:59:59.000Z

385

New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results  

DOE Green Energy (OSTI)

This report focuses on the evaluation of compressed natural gas (CNG) and diesel hybrid electric bus propulsion systems in New York City Transit's transit buses.

Chandler, K.; Eberts, E.; Eudy, L.

2006-01-01T23:59:59.000Z

386

Transition to turbulence and effect of initial conditions on three-dimensional compressible mixing in planar blast-wave-driven systems  

Science Conference Proceedings (OSTI)

Perturbations on an interface driven by a strong blast wave grow in time due to a combination of Rayleigh-Taylor, Richtmyer-Meshkov, and decompression effects. In this paper, results from three-dimensional (3D) numerical simulations of such a system under drive conditions to be attainable on the National Ignition Facility [E. M. Campbell, Laser Part. Beams 9, 209 (1991)] are presented. Using the multiphysics, adaptive mesh refinement, higher order Godunov Eulerian hydrocode, Raptor [L. H. Howell and J. A. Greenough, J. Comput. Phys. 184, 53 (2003)], the late nonlinear instability evolution, including transition to turbulence, is considered for various multimode perturbation spectra. The 3D post-transition state differs from the 2D result, but the process of transition proceeds similarly in both 2D and 3D. The turbulent mixing transition results in a reduction in the growth rate of the mixing layer relative to its pretransition value and, in the case of the bubble front, relative to the 2D result. The post-transition spike front velocity is approximately the same in 2D and 3D. Implications for hydrodynamic mixing in core-collapse supernovae are discussed.

Miles, A.R.; Blue, B.; Edwards, M.J.; Greenough, J.A.; Hansen, J.F.; Robey, H.F.; Drake, R.P.; Kuranz, C.; Leibrandt, D.R. [Lawrence Livermore National Laboratory, L-021, 7000 East Avenue, P.O. Box 808, Livermore, California 94551 (United States); University of Michigan, 2455 Hayward Street, Ann Arbor, Michigan 48109 (United States)

2005-05-15T23:59:59.000Z

387

Performance Evaluation of Hot Water Efficiency Plumbing System Using Thermal Valve  

E-Print Network (OSTI)

In Korea two popular water distribution systems—the branch type and the separate type systems—have serious drawbacks. The branch type suffers from temperature instability while the separate type suffers from excessive piping. Neither of them re-circulates water. The system proposed in this paper utilizes a water-conserving piping system with a thermostat valve. This paper compares the proposed system with that of the separate type. Our findings show that the proposed system wastes less water. After re-circulating for 78-87 seconds, water is available at set point temperature (40°C). Also, when multiple water taps are in use, the average temperature deviation is less than 0.6°C. Moreover, the proposed system has 50% less flow rate than the separate type system.

Cha, K. S.; Park, M. S.; Seo, H. Y.

2010-08-01T23:59:59.000Z

388

Efficiencies of adiabatic transfer in a multistate system R. M. Godun, C. L. Webb, M. K. Oberthaler, G. S. Summy, and K. Burnett  

E-Print Network (OSTI)

of the efficiency of adiabatic transfer between the Zeeman substates of the cesium ground level, using the D1 F 44- erally been confined to systems where atoms are trans- ferred between two Zeeman ground states for adiabatic transfer efficiency in a multistate system, the cesium ground level F 4. A sys- tem with a higher

Summy, Gil

389

Intelligent e-learning systems for evaluation of user's knowledge and skills with efficient information processing  

Science Conference Proceedings (OSTI)

This paper presents a new concept of an e-learning system with intelligent two-way speech communication between the system and its users. Computational intelligence methods allow for analysis, evaluation and assessment of user's knowledge and skills ... Keywords: artificial intelligence, cybernetics, e-learning system, mobile technology, speech interface, user-computer interaction

Wojciech Kacalak; Maciej Majewski; Jacek M. Zurada

2010-06-01T23:59:59.000Z

390

USE OF A DIESEL FUEL PROCESSOR FOR RAPID AND EFFICIENT REGENERATION OF SINGLE LEG NOX ADSORBER SYSTEMS  

DOE Green Energy (OSTI)

Lean NOx adsorber systems are one of the primary candidate technologies for the control of NOx from diesel engines to meet the 2007-2010 US emissions regulations, which require a 90% reduction of NOx from the 2004 regulations. Several of the technical challenges facing this technology are regeneration at low exhaust temperatures and the efficient use of diesel fuel to minimize fuel penalty. A diesel processor system has been developed and tested in a single leg NOx adsorber configuration on a diesel engine test stand. During NOx adsorber regeneration, this fuel processor system performs reduces the exhaust O2 level to zero and efficiently processes the diesel fuel to H2 and CO. Combined with a Nox adsorber catalyst, this system has demonstrated NOx reduction above 90%, regeneration of the NOx adsorber H2/CO pulses as short as 1 second and fuel penalties in the 3 to 4% range at 50% load. This fuel processor system can also be used to provide the desulfation cycle required with sulfur containing fuels as well as providing thermal management for PM filter regeneration.

Betta, R; Cizeron, J; Sheridan, D; Davis, T

2003-08-24T23:59:59.000Z

391

Quality assurance assessment of new efficient lighting systems for naval ships. Final report. Revision  

SciTech Connect

Ballasts and lamps, which have been selected to replace existing lamp/ballast systems based on improved performance, were tested to determine if they meet standard Naval MIL specifications. Fifty ballasts manufactured by Advance Transformer Corporation and Universal Manufacturing Corporation and 100 lamps manufactured by GTE were tested to determine their quality assurance and durability. These components met all of the MIL specifications that lamp/ballast systems in use must meet. These new systems have an improved system efficacy, 62 lumens per watt, and lower third harmonics, which will reduce the need for generating capacity for lighting on ships. An addendum to the original study describes the assessment of the performance of the advanced ballast system with a new F-17 fluorescent lamp. The results indicate the system performs reliably and shows increased efficacy. This new lamp/ballast system reduces the harmonic content to within Navy limits, and improves the power factor, resulting in a 50% reduction in line current.

Verderber, R.R.; Morse, O.; Dumm, C.

1984-12-01T23:59:59.000Z

392

Measure it, See it, Manage it: Using Real Time Data to Benchmark,Optimize, and Sustain System Energy Efficiency  

SciTech Connect

Even after years of training and awareness building at thestate and national level, industrial cross-cutting systems (motor-driven,steam, process heating) continue to offer significant opportunities forenergy savings. The US Department of Energy estimates these remainingsavings at more than 7 percent of all industrial energy use. This paperpresents a different approach to promoting industrial system energyefficiency -- providing plant personnel with ready access to data uponwhich to base energy management decisions.In 2005, a Del Monte Foodsfruit processing plant in Modesto, California worked with LawrenceBerkeley National Laboratory (LBNL)to specify and purchase permanentinstrumentation for monitoring their compressed air system. This work,completed as part of a demonstration project under a State TechnologiesAdvancement Collaborative (STAC) grant, was designed to demonstrate theeffectiveness of enterprise energy management (EEM), which is predicatedon the assumption that the energy efficiency of existing, cross-cuttingindustrial systems (motor-driven, steam) can be improved by providingmanagement and operating personnel with real-time data on energy use. Theinitial STAC grant provided for the installation and some initialanalyses, but did not address the larger issue of integrating these newdata into an ongoing energy management program for the compressed airsystem.The California Energy Commission (CEC) decided to support furtheranalysis to identify potential for air system optimization. Through theCEC's Energy in Agriculture Program, a compressed air system audit wasperformed by Tom Taranto to: Measure and document the system's baselineand CASE Index of present operation; Establish methods to sustain anongoing CASE Index measure of performance; Use AIRMaster+ to analyzesupply side performance as compared to the CASE Index; Identify demandside opportunities for efficiency and performance improvement; Assesssupply / demand balance and energy reduction opportunities; Evaluate thepresent air compressor control strategy and potential improvement, andCollect data to benchmark parameters for compressed air systems atsimilar facilities.This paper addresses the benefits and limitations ofboth continuous and targeted measurement in benchmarking, optimizing, andsustaining an efficient compressed air system. Included are methods usedin applying both of these measurements to a complex industrial system.Further, this paper will describe the results of these additionalanalyses and the plant response to them.

Taranto, Thomas; McKane, Aimee; Amon, Ricardo; Maulhardt, Michael

2007-07-02T23:59:59.000Z

393

Measure it, See it, Manage it: Using Real Time Data to Benchmark,Optimize, and Sustain System Energy Efficiency  

SciTech Connect

Even after years of training and awareness building at thestate and national level, industrial cross-cutting systems (motor-driven,steam, process heating) continue to offer significant opportunities forenergy savings. The US Department of Energy estimates these remainingsavings at more than 7 percent of all industrial energy use. This paperpresents a different approach to promoting industrial system energyefficiency -- providing plant personnel with ready access to data uponwhich to base energy management decisions.In 2005, a Del Monte Foodsfruit processing plant in Modesto, California worked with LawrenceBerkeley National Laboratory (LBNL)to specify and purchase permanentinstrumentation for monitoring their compressed air system. This work,completed as part of a demonstration project under a State TechnologiesAdvancement Collaborative (STAC) grant, was designed to demonstrate theeffectiveness of enterprise energy management (EEM), which is predicatedon the assumption that the energy efficiency of existing, cross-cuttingindustrial systems (motor-driven, steam) can be improved by providingmanagement and operating personnel with real-time data on energy use. Theinitial STAC grant provided for the installation and some initialanalyses, but did not address the larger issue of integrating these newdata into an ongoing energy management program for the compressed airsystem.The California Energy Commission (CEC) decided to support furtheranalysis to identify potential for air system optimization. Through theCEC's Energy in Agriculture Program, a compressed air system audit wasperformed by Tom Taranto to: Measure and document the system's baselineand CASE Index of present operation; Establish methods to sustain anongoing CASE Index measure of performance; Use AIRMaster+ to analyzesupply side performance as compared to the CASE Index; Identify demandside opportunities for efficiency and performance improvement; Assesssupply / demand balance and energy reduction opportunities; Evaluate thepresent air compressor control strategy and potential improvement, andCollect data to benchmark parameters for compressed air systems atsimilar facilities.This paper addresses the benefits and limitations ofboth continuous and targeted measurement in benchmarking, optimizing, andsustaining an efficient compressed air system. Included are methods usedin applying both of these measurements to a complex industrial system.Further, this paper will describe the results of these additionalanalyses and the plant response to them.

Taranto, Thomas; McKane, Aimee; Amon, Ricardo; Maulhardt, Michael

2007-07-02T23:59:59.000Z

394

Measure it, See it, Manage it: Using Real Time Data to Benchmark, Optimize, and Sustain System Energy Efficiency  

E-Print Network (OSTI)

is crucial to achieving sustainable energy efficiency in anoperation and sustainable energy efficiency. Targetednecessary to achieve sustainable energy savings. A

Taranto, Thomas; McKane, Aimee; Amon, Ricardo; Maulhardt, Michael

2008-01-01T23:59:59.000Z

395

Efficient energy transfer in light-harvesting systems, I: optimal temperature, reorganization energy, and spatial-temporal correlations  

E-Print Network (OSTI)

Understanding the mechanisms of efficient and robust energy transfer in light-harvesting systems provides new insights for the optimal design of artificial systems. In this paper, we use the Fenna-Matthews-Olson (FMO) protein complex and phycocyanin 645 (PC 645) to explore the general dependence on physical parameters that help maximize the efficiency and maintain its stability. With the Haken-Strobl model, the maximal energy transfer efficiency (ETE) is achieved under an intermediate optimal value of dephasing rate. To avoid the infinite temperature assumption in the Haken-Strobl model and the failure of the Redfield equation in predicting the Forster rate behavior, we use the generalized Bloch-Redfield (GBR) equation approach to correctly describe dissipative exciton dynamics and find that maximal ETE can be achieved under various physical conditions, including temperature, reorganization energy, and spatial-temporal correlations in noise. We also identify regimes of reorganization energy where the ETE changes monotonically with temperature or spatial correlation and therefore cannot be optimized with respect to these two variables.

Jianlan Wu; Fan Liu; Young Shen; Jianshu Cao; Robert J. Silbey

2010-08-13T23:59:59.000Z

396

REDESIGN OF HVAC SYSTEM TO IMPROVE ENERGY EFFICIENCY OF EDUCATIONAL BUILDING.  

E-Print Network (OSTI)

??An energy modeling software was used to analyze the current building configuration and simulations were performed in an attempt to redesign the current HVAC system… (more)

Hagene, Brian Matthew

2012-01-01T23:59:59.000Z

397

Field Measurements of Efficiency and Duct Effectiveness in Residential Forced Air Distributions Systems  

E-Print Network (OSTI)

sealing and insulating the duct system. ABSTRACT Forced airair conditioning, gas furnaces, electric furnaces and heat pumps. The retrofits consisted of sealing

Jump, D.A.

2011-01-01T23:59:59.000Z

398

Continuous flow microwave heating : evaluation of system efficiency and enzyme inactivation kinetics.  

E-Print Network (OSTI)

??A continuous flow microwave heating system was set up by using one domestic microwave oven (1000W nominal output at 2450MHz). Water was run through the… (more)

Lin, Man Guang, 1966-

2004-01-01T23:59:59.000Z

399

EFFICIENT PARALLELIZATION OF STOCHASTIC SIMULATION ALGORITHM FOR CHEMICALLY REACTING SYSTEMS ON THE GRAPHICS PROCESSING UNIT  

E-Print Network (OSTI)

REACTING SYSTEMS ON THE GRAPHICS PROCESSING UNIT H. Li ? L.The current generation of graphics processing units (GPU) issystems on the low cost graphics processing unit (GPU)

Li, Hong; Petzold, Linda

2009-01-01T23:59:59.000Z

400

Tools to Boost Steam System Efficiency, Software Tools for Industry, Industrial Technologies Program (ITP) (Fact Sheet)  

SciTech Connect

This fact sheet describes how the Industrial Technologies Program steam software tools can help industrial plants identify steam system improvements to save energy and money.

Not Available

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Evaluation of Thermal Efficiency and Energy Conservation of an Extraction / Condensing Cogeneration System.  

E-Print Network (OSTI)

??The extraction-condensing cogeneration system is a popular technology for heat and power integration which can be used by petrochemical process. To compare with back pressure… (more)

Ko, Yi-tsung

2004-01-01T23:59:59.000Z

402

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-Print Network (OSTI)

large tanks of hot molten salt are stored in containments soreceiver and the liquid molten salt coolant being heated;system; for example, high molten salt temperatures increases

Ho, Tony

2012-01-01T23:59:59.000Z

403

Quality assurance assessment of new efficient lighting systems for Naval ships. Final report  

SciTech Connect

Ballasts and lamps, which have been selected to replace existing lamp/ballast systems based on improved performance, were tested to determine if they meet standard Naval MIL specifications. Fifty ballasts manufactured by Advance Transformer Corporation and Universal Manufacturing Corp., and 100 lamps manufactured by GTE were tested to determine their quality assurance and durability. These components met all of the MIL specifications that lamp/ballast systems in use must meet. In addition, these new systems have an improved system efficacy, 62 lumens per watt, and lower third harmonics, which will reduce the need for generating capacity for lighting on ships.

Verderber, R.

1984-08-01T23:59:59.000Z

404

Systems Analyses of Advanced Brayton Cycles For High Efficiency Zero Emission Plants  

SciTech Connect

The ultimate goal of this program is to identify the power block cycle conditions and/or configurations which could increase the overall thermal efficiency of the Baseline IGCC by about 8% on a relative basis (i.e., 8% on a heat rate basis). This document presents the cycle conditions and/or the configurations for evaluation in an initial screening analysis. These cycle conditions and/or configurations for investigation in the screening analysis are identified by literature searches and brain storming sessions. The screening analysis in turn narrows down the number of promising cases for detailed analysis.

A. D. Rao; J. Francuz; A. Verma; G. S. Samuelsen

2006-10-30T23:59:59.000Z

405

The Human Side of Efficiency: The Value of Training in Plant Systems Optimization  

E-Print Network (OSTI)

Is the best way to improve industrial plant energy efficiency through a technical overhaul or management structure? The answer is that neither is effective without the other. Unfortunately, many operators concentrate their energies on technical improvements, ignoring the tremendous savings that can arise through low-risk, low-tech solutions such as training for proper maintenance and operation. This paper outlines the issues managers face in implementing an effective training program, the benefits that result from training, and further explains key areas where training is especially effective in reducing energy waste and increasing plant profitability.

Madan, R.

2002-04-01T23:59:59.000Z

406

Energy Efficiency | Open Energy Information  

Open Energy Info (EERE)

Efficiency Jump to: navigation, search Energy Efficiency refers to products or systems using less energy to do the same or better job than conventional products or systems. Energy...

407

The Australian domain name registration system : a more efficient system for the promotion of liberalisation, consumer protection and growth.  

E-Print Network (OSTI)

??This thesis is about the Australian domain name system and, in particular, the principles governing the registration of domain names in the '.au' country code… (more)

Ng, Jenny Swee Gaik

2009-01-01T23:59:59.000Z

408

Efficient reasoning  

Science Conference Proceedings (OSTI)

Many tasks require “reasoning”—i.e., deriving conclusions from a corpus of explicitly stored information—to solve their range of problems. An ideal reasoning system would produce all-and-only the correct answers ... Keywords: efficiency trade-offs, soundness/completeness/expressibility

Russell Greiner; Christian Darken; N. Iwan Santoso

2001-03-01T23:59:59.000Z

409

Evolutionary and adaptive strategies for efficient search across whole system engineering design hierarchies  

Science Conference Proceedings (OSTI)

Evolutionary and Adaptive strategies (ES & AS) for diverse multilevel search across a preliminary, whole-system design hierarchy defined by discrete and continuous variable parameters are described. Such strategies provide high-level decision support ... Keywords: Adaptive Search, Design Hierarchies, Genetic Algorithms, Whole System Design

I. C. Parmee

1998-11-01T23:59:59.000Z

410

Context and profile based cascade classifier for efficient people detection and safety care system  

Science Conference Proceedings (OSTI)

This study propose a system of extracting and tracking objects for a multimedia system and addresses how to extract the head feature from an object area. It is observed in images taken from real-time records like a video, there is always a variance in ... Keywords: Context-awareness, Feature selection, Human detection, Tracking

Kang-Dae Lee; Mi Young Nam; Kyung-Yong Chung; Young-Ho Lee; Un-Gu Kang

2013-03-01T23:59:59.000Z

411

Cogeneration and beyond: The need and opportunity for high efficiency, renewable community energy systems  

SciTech Connect

The justification, strategies, and technology options for implementing advanced district heating and cooling systems in the United States are presented. The need for such systems is discussed in terms of global warming, ozone depletion, and the need for a sustainable energy policy. Strategies for implementation are presented in the context of the Public Utilities Regulatory Policies Act and proposed new institutional arrangements. Technology opportunities are highlighted in the areas of advanced block-scale cogeneration, CFC-free chiller technologies, and renewable sources of heating and cooling that are particularly applicable to district systems.

Gleason, T.C.J.

1992-06-01T23:59:59.000Z

412

Towards a Secure and Efficient System for End-to-End Provenance  

E-Print Network (OSTI)

Work on the End-to-End Provenance System (EEPS) began in the late summer of 2009. The EEPS effort seeks to explore the three central questions in provenance systems: (1) “Where and how do I design secure hostlevel provenance collecting instruments (called provenance monitors)?”; (2) “How do I extend completeness and accuracy guarantees to distributed systems and computations?”; and (3) “What are the costs associated with provenance collection? ” This position paper discusses our initial exploration into these issues and posits several challenges to the realization of the EEPS vision.

Patrick Mcdaniel; Kevin Butler; Steve Mclaughlin; Radu Sion; Erez Zadok; Marianne Winslett

2010-01-01T23:59:59.000Z

413

Enhancing Efficiency and Robustness of a Photovoltaic Power System under Partial Shading  

E-Print Network (OSTI)

construct a HEES system with high-power- capacity EES arrays (supercapacitor arrays) together with by the supercapacitor arrays. A PV module exhibits highly non-linear current-voltage (I-V) characteristics and mandates

Pedram, Massoud

414

Fundamental performance limits and efficient polices for Transportation-On-Demand systems  

E-Print Network (OSTI)

Transportation-On-Demand (TOD) systems, where users generate requests for transportation from a pick-up point to a delivery point, are already very popular and are expected to increase in usage dramatically as the inconvenience ...

Pavone, Marco

415

Energy-Efficient Delay-Constrained Transmission and Sensing for Cognitive Radio Systems  

E-Print Network (OSTI)

In this work we study energy-efficient transmission for Cognitive Radio (CR) which opportunistically operates on Primary User's (PU's) channel through spectrum sensing. Spectrum sensing and compulsory idling (for incumbent protection) introduce energy-overheads for Secondary User's (SU's) operations, and thus an appropriate balance between energy consumption in data transmission and energy-overheads is required. We formulate this problem as a discrete-time Markov Decision Process (MDP) in which the SU aims at minimizing its average cost (including both energy consumption and delay cost) to finish a target traffic payload through an appropriate rate allocation. Based on Certainty Equivalent Control, we propose a low-complexity rate-adaptation policy that achieves comparable performance as the optimal policy. With the low-complexity policy, we quantify the impact of energy-overheads (including the power consumption for spectrum sensing and compulsory idling) on the SU transmission strategy. Specifically, the SU...

Wu, Yuan; Tsang, Danny H K; Qian, Liping

2012-01-01T23:59:59.000Z

416

Chapter 4, Small Commercial and Residential Unitary and Split System HVAC Cooling Equipment-Efficiency Upgrade Evaluation Protocol: The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

4: Small Commercial 4: Small Commercial and Residential Unitary and Split System HVAC Cooling Equipment-Efficiency Upgrade Evaluation Protocol David Jacobson, Jacobson Energy Research Subcontract Report NREL/SR-7A30-53827 April 2013 The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures 4 - 1 Chapter 4 - Table of Contents 1 Measure Description .............................................................................................................. 2 2 Application Conditions of Protocol ....................................................................................... 3 2.1 Programs with Enhanced Measures ................................................................................. 5 3 Savings Calculations .............................................................................................................. 6

417

Advanced Building Efficiency Testbed Initiative/Intelligent Workplace Energy Supply System; ABETI/IWESS  

DOE Green Energy (OSTI)

ABETI/IWESS is a project carried out by Carnegie Mellon's Center for Building Performance and Diagnostics, the CBPD, supported by the U.S. Department of Energy/EERE, to design, procure, install, operate, and evaluate an energy supply system, an ESS, that will provide power, cooling, heating and ventilation for CBPD's Intelligent Workplace, the IW. The energy sources for this system, the IWESS, are solar radiation and bioDiesel fuel. The components of this overall system are: (1) a solar driven cooling and heating system for the IW comprising solar receivers, an absorption chiller, heat recovery exchanger, and circulation pump; (2) a bioDiesel fueled engine generator with heat recovery exchangers, one on the exhaust to provide steam and the other on the engine coolant to provide heated water; (3) a ventilation system including an enthalpy recovery wheel, an air based heat pump, an active desiccant wheel, and an air circulation fan; and (4) various convective and radiant cooling/heating units and ventilation air diffusers distributed throughout the IW. The goal of the ABETI/IWESS project is to demonstrate an energy supply system for a building space that will provide a healthy, comfortable environment for the occupants and that will reduce the quantity of energy consumed in the operation of a building space by a factor of 2 less than that of a conventional energy supply for power, cooling, heating, and ventilation based on utility power and natural gas fuel for heating.

David Archer; Frederik Betz; Yun Gu; Rong Li; Flore Marion; Sophie Masson; Ming Qu; Viraj Srivastava; Hongxi Yin; Chaoqin Zhai; Rui Zhang; Elisabeth Aslanian; Berangere Lartigue

2008-05-31T23:59:59.000Z

418

Event Indexing Systems for Efficient Selection and Analysis of HERA Data  

E-Print Network (OSTI)

The design and implementation of two software systems introduced to improve the eciency of oine analysis of event data taken with the ZEUS Detector at the HERA electron-proton collider at DESY are presented. Two dierent approaches were made, one using a set of event directories and the other using a tag database based on a commercial object-oriented database management system. These are described and compared. Both systems provide quick direct access to individual collision events in a sequential data store of several terabytes, and they both considerably improve the event analysis eciency. In particular the tag database provides a very exible selection mechanism and can dramatically reduce the computing time needed to extract small subsamples from the total event sample. Gains as large as a factor 20 have been obtained. now at Fermi National Accelerator Laboratory, Batavia, USA y on leave at Stanford Linear Accelerator Laboratory, Stanford, USA z now at NIKHEF, Amsterdam, The Netherlands 1

L. A. T. Bauerdick; Adrian Fox-murphy; Tobias Haas; Stefan Stonjek; Enrico Tassi

2001-01-01T23:59:59.000Z

419

Field Testing of Energy-Efficient Flood-Damage-Resistant Residential Envelope Systems Summary Report  

SciTech Connect

The primary purpose of the project was to identify materials and methods that will make the envelope of a house flood damage resistant. Flood damage resistant materials and systems are intended to be used to repair houses subsequent to flooding. This project was also intended to develop methods of restoring the envelopes of houses that have been flooded but are repairable and may be subject to future flooding. Then if the house floods again, damage will not be as extensive as in previous flood events and restoration costs and efforts will be minimized. The purpose of the first pair of field tests was to establish a baseline for typical current residential construction practice. The first test modules used materials and systems that were commonly found in residential envelopes throughout the U.S. The purpose of the second pair of field tests was to begin evaluating potential residential envelope materials and systems that were projected to be more flood-damage resistant and restorable than the conventional materials and systems tested in the first pair of tests. The purpose of testing the third slab-on-grade module was to attempt to dry flood proof the module (no floodwater within the structure). If the module could be sealed well enough to prevent water from entering, then this would be an effective method of making the interior materials and systems flood damage resistant. The third crawl space module was tested in the same manner as the previous modules and provided an opportunity to do flood tests of additional residential materials and systems. Another purpose of the project was to develop the methodology to collect representative, measured, reproducible (i.e. scientific) data on how various residential materials and systems respond to flooding conditions so that future recommendations for repairing flood damaged houses could be based on scientific data. An additional benefit of collecting this data is that it will be used in the development of a standard test procedure which could lead to the certification of building materials and systems as flood damage resistant.

Aglan, H.

2005-08-04T23:59:59.000Z

420

Direct electrochemical conversion of carbon: systems for efficient conversion of fossil fuels to electricity  

DOE Green Energy (OSTI)

The direct electrochemical conversion of carbon involves discharge of suspensions of reactive carbon particles in a molten salt electrolyte against an oxygen (air) cathode. (Figure 1). The free energy and the enthalpy of the oxidation reaction are nearly identical. This allows theoretical efficiencies ({Delta}G(T)/{Delta}H) to approach 100% at temperatures from 500 to 800 C. Entropy heat losses are therefore negligible. The activities of the elemental carbon and of the carbon dioxide product are uniform throughout the fuel cell and constant over discharge time. This stabilizes cell EMF and allows full utilization of the carbon fuel in a single pass. Finally, the energy cost for pyrolysis of hydrocarbons is generally very low compared with that of steam reforming or water gas reactions. Direct electrochemical conversion of carbon might be compared with molten carbonate fuel cell using carbon rather than hydrogen. However, there are important differences. There is no hydrogen involved (except from trace water contamination). The mixture of molten carbonate and carbon is not highly flammable. The carbon is introduced in as a particulate, rather than as a high volume flow of hydrogen. At the relatively low rates of discharge (about 1 kA/m{sup 2}), the stoichiometric requirements for carbon dioxide by the cathodic reaction may be met by diffusion across the thin electrolyte gap. We report recent experimental work at LLNL using melt slurries of reactive carbons produced by the thermal decomposition of hydrocarbons. We have found that anodic reactivity of carbon in mixed carbonate melts depends strongly on form, structure and nano-scale disorder of the materials, which are fixed by the hydrocarbon starting material and the conditions of pyrolysis. Thus otherwise chemically pure carbons made by hydrocarbon pyrolysis show rates at fixed potentials that span an order of magnitude, while this range lies 1-2 orders of magnitude higher than the current density of graphite plate electrodes. One carbon materials was identified which delivered anode current densities of 1 kA/m{sup 2} at 0.8 V (i.e., 80% efficiency, based on the standard enthalpy of carbon/oxygen reaction, and assuming full conversion), which we believe to be sufficiently great to allow practical application in fuel cell arrays. Since the hydrocarbon starting materials are ''ash free,'' entrainment of ash into the melt is not limiting. Finally, the use of fine carbon particulates in slurries avoids cost and logistics of carbon electrode manufacture and distribution.

Cooper, J F; Cherepy, N; Krueger, R

2000-08-10T23:59:59.000Z

Note: This page contains sample records for the topic "transit systems efficient" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

An enhanced dynamic voltage scaling scheme for energy-efficient embedded real-time control systems  

Science Conference Proceedings (OSTI)

Real-Time Dynamic Voltage Scaling (RT-DVS) has been one of the most important techniques for energy savings in battery-powered embedded systems. However, pure RT-DVS approaches rarely take into account the actual performance requirements of the target ...

Feng Xia; Youxian Sun

2006-05-01T23:59:59.000Z

422

High efficiency vapor-fed AMTEC system for direct conversion. Appendices for final report  

DOE Green Energy (OSTI)

This report consists of four appendices for the final report. They are: Appendix A: 700 C Vapor-Fed AMTEC Cell Calculations; Appendix B: 700 C Vapor-Fed AMTEC Cell Parts Drawings; Appendix C: 800 C Vapor-Fed AMTEC Cell Calculations; and Appendix D: 800 C Wick-Pumped AMTEC Cell System Design.

Anderson, W.G.; Bland, J.J.

1997-05-23T23:59:59.000Z

423

OBSERVE: Occupancy-Based System for Efficient Reduction of HVAC Energy  

E-Print Network (OSTI)

office build- ings [9]. This type of system is often used since it is able to heat and cool areas while - Merced {verickson,mcarreira-perpinan,acerpa}@ucmerced.edu ABSTRACT Heating, cooling and ventilation uncomfortable [13]. If not properly calibrated, these sensors can also be inaccurate [13]. Electrical loads have

Carreira-Perpiñán, Miguel Á.

424

A Hamiltonian approach to compute an energy efficient trajectory for a servomotor system  

Science Conference Proceedings (OSTI)

This paper considers a nonlinear constrained optimal control problem (NCOCP) originated from energy optimal trajectory planning of servomotor systems. Solving the exact optimal solution is challenging because of the nonlinear and switching cost function, ... Keywords: Constraints, Optimal trajectory, Servomotors, Switching functions

Yebin Wang, Koichiro Ueda, Scott A. Bortoff

2013-12-01T23:59:59.000Z

425

Flexible on-chip power delivery for energy efficient heterogeneous systems  

Science Conference Proceedings (OSTI)

Heterogeneous systems-on-chip pose a challenge for power delivery given the variety of needs for different components. In this paper, we describe recent work that leverages power switches and conventional EDA toolflows to implement a set of power delivery ... Keywords: PDVS, dynamic voltage scaling, leakage, low power design, variable weighted headers

Benton H. Calhoun, Kyle Craig

2013-05-01T23:59:59.000Z

426

Improving schedulability and energy efficiency for real-time systems with (m,k)-guarantee  

Science Conference Proceedings (OSTI)

In this paper, we explore improving the schedulability and energy performance for real-time systems with (m, k)-constraints, which require that at least m out of any k consecutive jobs of a task meet their deadlines. The preliminary ...

Linwei Niu, Kuai Xu

2013-07-01T23:59:59.000Z

427

Simulation and analysis of high efficiency absorption systems for solar cooling  

DOE Green Energy (OSTI)

A flexible modular computer code was developed for simulation of absorption systems. The code is capable to investigate, on a comparable basis, various cycles configurations with a variety of working fluids. In Phase 1 of the program, two open cycle absorption systems for solar energy were successfully simulated. Modifications which were applied to the code in Phase 2, allowed the analysis of systems with volatile absorbents, as used in advanced, high COP, absorption systems such as the GAX cycle. Ammonia-water database was developed into equation form and introduced to the code. That eliminated discontinuities in evaluating differentials used in the solver. Properties calculated with these equations fit well the tabulated data. This and other modifications allowed to model absorption cycles using ammonia-water. Single effect cycles converged in most ranges. Direct analysis of the code to advanced cycles, such as GAX, still encountered some convergence problems. It was, however, possible to analyze the GAX cycle in groups. The results show that high COP's are obtainable and are compatible with those reached by LBL. The properties of two additional pairs, that were developed in BG Univ., are reported. 27 refs., 13 figs., 13 tabs.

Shavit, A.; Haim, I. (Technion-Israel Inst. of Tech., Haifa (Israel). Faculty of Mechanical Engineering); Borde, I.; Jelinek, M. (Ben-Gurion Univ. of the Negev, Beersheba (Israel). Applied Research Inst.)

1989-05-31T23:59:59.000Z

428

IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 1 EPPA: An Efficient and Privacy-Preserving  

E-Print Network (OSTI)

to smart grid operation center, data aggregation is performed directly on ciphertext at local gateways be matched by the power supply and transmission capacity in the electric power grid. While swift advances electricity distribution. Modernizing the aging power system is currently a strategic plan in many countries

Shen, Xuemin "Sherman"

429

North American Electricity Infrastructure: System Security, Quality, Reliability, Availability, and Efficiency  

E-Print Network (OSTI)

1 North American Electricity Infrastructure: System Security, Quality, Reliability, Availability for reliable and disturbance-free electricity. The massive power outages in the United States, Canada, UK and Italy in 2003 underscored electricity infrastructure's vulnerabilities [1-11]. This vital yet complex

Amin, S. Massoud

430

Modelling societal transitions with agent transformation  

Science Conference Proceedings (OSTI)

Transition models explain long-term and large-scale processes fundamentally changing the structure of a societal system. Our concern is that most transition models are too static. Although they capture a move of focus from static equilibria to transitions ... Keywords: Agent-based modelling, Integrated sustainability assessment, Societal transitions

Michel Schilperoord; Jan Rotmans; Noam Bergman

2008-12-01T23:59:59.000Z

431

Small Hydropower Systems: Energy Efficiency and Renewable Energy Clearinghouse (EREC) Fact Sheet  

NLE Websites -- All DOE Office Websites (Extended Search)

you're considering building a small you're considering building a small hydropower system on water flowing through your property, you have a long tradition from which to draw your inspi- ration. Two thousand years ago, the Greeks learned to harness the power of running water to turn the massive wheels that rotated the shafts of their wheat flour grinders. And in the hydropower heyday of the 18th century, thousands of towns and cities worldwide were located around small hydropower sites. Today, small hydropower projects offer emissions-free power solutions for many remote communities throughout the world-such as those in Nepal, India, China, and Peru-as well as for highly industrialized countries, like the United States. This fact sheet will help you determine whether a small hydropower system will

432

Power-Efficient Data Management for a Wireless Structural Monitoring System  

E-Print Network (OSTI)

A low-cost wireless sensing unit for installation in structural monitoring systems is proposed. To eliminate the high cost of installing cables widely used in conventional systems, each wireless sensing unit includes wireless radios for reliable communication of response measurements. With wireless radios consuming large amounts of power, battery preservation can be achieved by limiting the use of the wireless channel. This study explores two approaches to reducing the power demands of the wireless sensing unit. First, embedded engineering analyses are carried out by the sensing unit’s computational core to avoid transmission of long time-history records. Various engineering algorithms are encoded and executed using structural response data to illustrate the power saved in local data interrogation. Second, lossless data compression using Huffman coding is employed to reduce the size of data packets wirelessly transmitted.

J. P. Lynch; A. Sundararajan; K. H. Law; A. S. Kiremidjian; E. Carryer

2003-01-01T23:59:59.000Z

433

Supersonic Technology for CO2 Capture: A High Efficiency Inertial CO2 Extraction System  

Science Conference Proceedings (OSTI)

IMPACCT Project: Researchers at ATK and ACENT Laboratories are developing a device that relies on aerospace wind-tunnel technologies to turn CO2 into a condensed solid for collection and capture. ATK’s design incorporates a special nozzle that converges and diverges to expand flue gas, thereby cooling it off and turning the CO2 into solid particles which are removed from the system by a cyclonic separator. This technology is mechanically simple, contains no moving parts and generates no chemical waste, making it inexpensive to construct and operate, readily scalable, and easily integrated into existing facilities. The increase in the cost to coal-fired power plants associated with introduction of this system would be 50% less than current technologies.

None

2010-07-01T23:59:59.000Z

434

Energy efficiency lighting on board naval ships: Phase 2 (The T-8 lamp system)  

SciTech Connect

This report describes the development and performance of the T-8 fluorescent lamp-ballast system. Similar to the Phase I effort, the cooperation of the lamp and ballast companies (GTE, North American Philips Lighting, and IOTA Engineering) were required for the successful result. The above companies submitted prototype lamps and ballasts to the Lawrence Berkeley Laboratory Lighting Group to evaluate. The lamp designs were modified as required and the optimum system selected. Two-lamp designs and one ballast were chosen and tested to determine if they met the Navy specifications. The second section describes the lamp-ballast specifications. This section includes the measured thermal performance from an ambient of 10/degree/C to 60/degree/C. 1 ref., 8 figs., 11 tabs.

Verderber, R.R.

1987-01-31T23:59:59.000Z

435

Efficiency calculations for the direct energy conversion system of the Cadarache neutral beam injectors  

DOE Green Energy (OSTI)

A prototype energy conversion system is presently in operation at Cadarache, France. Such a device is planned for installation on each six neutral beam injectors for use in the Tore Supra experiment in 1989. We present calculations of beam performance that may influence design considerations. The calculations are performed with the DART charged particle beam code. We investigate the effects of cold plasma, direct energy conversion and neutral beam production. 4 refs., 6 figs., 4 tabs.

White, R.C.

1988-06-08T23:59:59.000Z

436

Energy-efficiency and storage flexibility in the blue file system  

E-Print Network (OSTI)

A fundamental vision driving pervasive computing research is access to personal and shared data anywhere at anytime. In many ways, this vision is close to being realized. Wireless networks such as 802.11 offer connectivity to small, mobile devices. Portable storage, such as mobile disks and USB keychains, let users carry several gigabytes of data in their pockets. Yet, at least three substantial barriers to pervasive data access remain. First, power-hungry network and storage devices tax the limited battery capacity of mobile computers. Second, the danger of viewing stale data or making inconsistent updates grows as objects are replicated across more computers and portable storage devices. Third, mobile data access performance can suffer due to variable storage access times caused by dynamic power management, mobility, and use of heterogeneous storage devices. To overcome these barriers, we have built a new distributed file system called BlueFS. Compared to the Coda file system, BlueFS reduces file system energy usage by up to 55% and provides up to 3 times faster access to data replicated on portable storage. 1

Edmund B. Nightingale; Jason Flinn

2004-01-01T23:59:59.000Z

437

Clean air program: Design guidelines for bus transit systems using hydrogen as an alternative fuel. Final report, September 1997--May 1998  

SciTech Connect

Alternative fuels such as Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquified Petroleum Gas (LPG), and alcohol fuels (methanol and ethanol) are already being used in commercial vehicles and transit buses in revenue service. Hydrogen, which has better air quality characteristics as a vehicle fuel, is being used in research demonstration projects in fuel cell powered buses, as well as in internal combustion engines in automobiles and small trucks. At present, there are no facility guidelines to assist transit agencies (and others) contemplating the use of hydrogen as an alternative fuel. This document addresses the various issues involved. Hydrogen fuel properties, potential hazards, fuel requirements for specified levels of bus service, applicable codes and standards, ventilation, and electrical classification are indicated in this document. These guidelines also present various facility and bus design issues that need to be considered by a transit agency to ensure safe operations when using hydrogen as an alternative fuel. Fueling facility, garaging facility, maintenance facility requirements and safety practices are discussed. Critical fuel-related safety issues in the design of the related system on the bus are also identified. A system safety assessment and hazard resolution process is also presented. This approach may be used to select design strategies which are economical, yet ensure a specified level of safety.

Raj, P.K.; Hathaway, W.T.; Kangas, R.A.

1998-10-01T23:59:59.000Z

438

Control Scheme Modifications Increase Efficiency of Steam Generation System at ExxonMobil Gas Plant. Office of Industrial Technologies (OIT) Chemicals BestPractices Project Case Study  

Science Conference Proceedings (OSTI)

This case study highlights control scheme modifications made to the steam system at ExxonMobil's Mary Ann Gas Plant in Mobile, Alabama, which improved steam flow efficiency and reduced energy costs.

Not Available

2002-01-01T23:59:59.000Z

439

Novel High Efficiency Photovoltaic Devices Based on the III-N Material System: Final Technical Report, 7 December 2005 - 29 August 2008  

DOE Green Energy (OSTI)

The research shows that InGaN material system can be used to realize high-efficiency solar cells, making contributions to growth, modeling, understanding of loss mechanisms, and process optimization.

Hornsberg, C.; Doolittle, W. A.; Ferguson, I.

2008-10-01T23:59:59.000Z

440

Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district  

E-Print Network (OSTI)

Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district heating system ­ and makes a proposal for a technical and economic improvement. Monitoring of water quality in district heating systems is necessary

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441

HybridStore: A Cost-Efficient, High-Performance Storage System Combining SSDs and HDDs  

SciTech Connect

Unlike the use of DRAM for caching or buffering, certain idiosyncrasies of NAND Flash-based solid-state drives (SSDs) make their integration into existing systems non-trivial. Flash memory suffers from limits on its reliability, is an order of magnitude more expensive than the magnetic hard disk drives (HDDs), and can sometimes be as slow as the HDD (due to excessive garbage collection (GC) induced by high intensity of random writes). Given these trade-offs between HDDs and SSDs in terms of cost, performance, and lifetime, the current consensus among several storage experts is to view SSDs not as a replacement for HDD but rather as a complementary device within the high-performance storage hierarchy. We design and evaluate such a hybrid system called HybridStore to provide: (a) HybridPlan: improved capacity planning technique to administrators with the overall goal of operating within cost-budgets and (b) HybridDyn: improved performance/lifetime guarantees during episodes of deviations from expected workloads through two novel mechanisms: write-regulation and fragmentation busting. As an illustrative example of HybridStore s ef cacy, HybridPlan is able to nd the most cost-effective storage con guration for a large scale workload of Microsoft Research and suggest one MLC SSD with ten 7.2K RPM HDDs instead of fourteen 7.2K RPM HDDs only. HybridDyn is able to reduce the average response time for an enterprise scale random-write dominant workload by about 71% as compared to a HDD-based system.

Kim, Youngjae [ORNL; Gupta, Aayush [Pennsylvania State University, University Park, PA; Urgaonkar, Bhuvan [Pennsylvania State University; Piotr, Berman [Pennsylvania State University, University Park, PA; Sivasubramaniam, Anand [Pennsylvania State University

2011-01-01T23:59:59.000Z

442

Efficient System Design and Sustainable Finance for China's Village Electrification Program: Preprint  

DOE Green Energy (OSTI)

This paper describes a joint effort of the Institute for Electrical Engineering of the Chinese Academy of Sciences (IEE), and the U.S. National Renewable Energy Laboratory (NREL) to support China's rural electrification program. This project developed a design tool that provides guidelines both for off-grid renewable energy system designs and for cost-based tariff and finance schemes to support them. This tool was developed to capitalize on lessons learned from the Township Electrification Program that preceded the Village Electrification Program. We describe the methods used to develop the analysis, some indicative results, and the planned use of the tool in the Village Electrification Program.

Ma, S.; Yin, H.; Kline, D. M.

2006-08-01T23:59:59.000Z

443

Utilization of Advanced Conductors to Improve Transmission System Utilization and Efficiency  

Science Conference Proceedings (OSTI)

Entergy has recently carried out a project on utilization of an advanced conductor to solve a reliability issue related to components overloading at N-1 conditions. The 230-kV Line 195 (Hartburg Inland Orange McLewis Helbig) in Entergy's system is one of the primary sources into the Beaumont/Port Arthur area. The single contingency loss of 500-kV Line 547 (Cypress Hartburg) causes thermal overloads of this line. To prevent conditions from overloading and potential cascading effects, the power transmitted...

2011-12-23T23:59:59.000Z

444

Efficient System Design and Sustainable Finance for China's Village Electrification Program: Preprint  

SciTech Connect

This paper describes a joint effort of the Institute for Electrical Engineering of the Chinese Academy of Sciences (IEE), and the U.S. National Renewable Energy Laboratory (NREL) to support China's rural electrification program. This project developed a design tool that provides guidelines both for off-grid renewable energy system designs and for cost-based tariff and finance schemes to support them. This tool was developed to capitalize on lessons learned from the Township Electrification Program that preceded the Village Electrification Program. We describe the methods used to develop the analysis, some indicative results, and the planned use of the tool in the Village Electrification Program.

Ma, S.; Yin, H.; Kline, D. M.

2006-08-01T23:59:59.000Z

445