Sample records for brakes front wheel

  1. Mechanical front wheel drive tractors: a field performance study

    E-Print Network [OSTI]

    Babacz, William Adam

    1986-01-01T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of 2WD and NFWD Tractors . . . . . . . . . . . . . . . . . . Comparison of NFWD Tractors Operating in FWA and 2WO Modes III TRACTOR PERFORNANCE NONITORING SYSTEM Instrumentation System Rear Axle Torque . Front Axle Driveline Torque Front...-sized tractors and may be operated with the mechanical front wheel drive engaged in a front wheel assist (FWA) mode or disengaged in a two-wheel drive (2WD) mode. The advertised benefits of NFWD are increased traction and reduced fuel consumption. Agricultural...

  2. Integrated vehicle dynamics control via coordination of active front steering and rear braking

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Integrated vehicle dynamics control via coordination of active front steering and rear brakingComputer and Automation Research Institue, Hungarian Academy of Sciences, Kende u. 13-17, H-1111, Budapest, Hungary, Email front steering and rear braking in a driver- assist system for vehicle yaw control. The proposed control

  3. "By the hundred's of thousand's, these unlikely transportation revolutionaries are forgoing the safety of a steel cage with airbags and anti-lock brakes for a wispy two-wheeled exoskeleton as they make their way to work,

    E-Print Network [OSTI]

    Duchowski, Andrew T.

    the safety of a steel cage with airbags and anti-lock brakes for a wispy two-wheeled exoskeleton as they make

  4. Adaptive controller for regenerative and friction braking system

    DOE Patents [OSTI]

    Davis, R.I.

    1990-10-16T23:59:59.000Z

    A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.

  5. Brake blending strategy for a hybrid vehicle

    DOE Patents [OSTI]

    Boberg, Evan S. (Hazel Park, MI)

    2000-12-05T23:59:59.000Z

    A hybrid electric powertrain system is provided including a transmission for driving a pair of wheels of a vehicle and a heat engine and an electric motor/generator coupled to the transmission. A friction brake system is provided for applying a braking torque to said vehicle. A controller unit generates control signals to the electric motor/generator and the friction brake system for controllably braking the vehicle in response to a drivers brake command. The controller unit determines and amount of regenerative torque available and compares this value to a determined amount of brake torque requested for determining the control signals to the electric motor/generator and the friction brake system.

  6. Braking system

    DOE Patents [OSTI]

    Norgren, D.U.

    1982-09-23T23:59:59.000Z

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  7. Electric vehicle regenerative antiskid braking and traction control system

    DOE Patents [OSTI]

    Cikanek, S.R.

    1995-09-12T23:59:59.000Z

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

  8. Electric vehicle regenerative antiskid braking and traction control system

    DOE Patents [OSTI]

    Cikanek, Susan R. (Wixom, MI)

    1995-01-01T23:59:59.000Z

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

  9. On Steady-State Cornering Equilibria for Wheeled Vehicles with Drift Efstathios Velenis, Emilio Frazzoli and Panagiotis Tsiotras

    E-Print Network [OSTI]

    Tsiotras, Panagiotis

    wheel steering controller appeared in [14]. The authors of that work used a single-track vehicle model (independent braking control on all four wheels) [1], active steering [2], [3], and, more recently, via including differential braking, traction control, active steering and sus- pension. Alternative means

  10. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOE Patents [OSTI]

    Cikanek, S.R.

    1994-10-25T23:59:59.000Z

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.

  11. Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

    DOE Patents [OSTI]

    Cikanek, Susan R. (Wixom, MI)

    1994-01-01T23:59:59.000Z

    An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.

  12. Just build it! : a fully functional concept vehicle using robotic wheels

    E-Print Network [OSTI]

    Schmitt, Peter, S.M. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    Interest in electric vehicle drive units is resurging with the proliferation of hybrid and electric vehicles. Currently emerging key-technologies are: in-wheel motors, electric braking, integrated steering activators and ...

  13. Vehicle brake testing system

    DOE Patents [OSTI]

    Stevens, Samuel S. (Harriman, TN); Hodgson, Jeffrey W. (Lenoir City, TN)

    2002-11-19T23:59:59.000Z

    This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.

  14. Preliminary survey report: control technology for brake lining at Northwest Local School District, Cincinnati, Ohio

    SciTech Connect (OSTI)

    Cooper, T.C.; McGlothlin, J.D.; Godbey, F.W.; Sheehy, J.W.; O'Brien, D.M.

    1986-05-01T23:59:59.000Z

    A walk-through survey of control technology for reducing asbestos exposure during maintenance and repair of vehicular brakes was conducted at Northwest Local School District, Cincinnati, Ohio in January, 1986. The primary method for controlling and collecting dust during brake servicing was a wet-washing technique and good work practices, ensuring that exposure to hazardous physical or chemical agents was reduced or eliminated. Also available was an enclosed-type brake assembly cleaner designed to be connected to the shop air and a vacuum system. The brake assembly cleaner did not have a viewing port to examine the area being cleaned. The operator had to remove the unit to inspect the cleaned area potentially exposing himself to any dust remaining on the brake shoes or hub. The unit itself was a potential dust source as it was designed to fit 16-inch wheels and did not form a tight seal on the smaller 15-inch wheels of the newer buses. The authors conclude that the wet wash technique is an excellent method for controlling asbestos emissions during brake maintenance. The vacuum brake-assembly cleaner is inadequate and potentially hazardous. An in-depth survey of the wet technique is recommended.

  15. Grinding Wheel System

    DOE Patents [OSTI]

    Malkin, Stephen (Amherst, MA); Gao, Robert (Amherst, MA); Guo, Changsheng (South Windsor, CT); Varghese, Biju (Worthington, OH); Pathare, Sumukh (Waltham, MA)

    2003-08-05T23:59:59.000Z

    A grinding wheel system includes a grinding wheel with at least one embedded sensor. The system also includes an adapter disk containing electronics that process signals produced by each embedded sensor and that transmits sensor information to a data processing platform for further processing of the transmitted information.

  16. Grinding Wheel System

    DOE Patents [OSTI]

    Malkin, Stephen (Amherst, MA); Gao, Robert (Amherst, MA); Guo, Changsheng (South Windsor, CT); Varghese, Biju (Worthington, OH); Pathare, Sumukh (Waltham, MA)

    2006-01-10T23:59:59.000Z

    A grinding wheel system includes a grinding wheel with at least one embedded sensor. The system also includes an adapter disk containing electronics that process signals produced by each embedded sensor and that transmits sensor information to a data processing platform for further processing of the transmitted information.

  17. A CASTOR WHEEL CONTROLLER FOR DIFFERENTIAL DRIVE WHEELCHAIRS

    E-Print Network [OSTI]

    Bremen, Universität

    on the front axis), and the tire material (rubber), the addi- tional force to change the angle of the castor by the equipped laser scanners and brakes in time if an obstacle is danger- ously close to the wheelchair. During for different grounds and tire materials, but without a projection of these forces to the differential drive

  18. Real-Time Dynamic Brake Assessment Proof of Concept Final Report

    SciTech Connect (OSTI)

    Lascurain, Mary Beth [ORNL; Franzese, Oscar [ORNL; Capps, Gary J [ORNL

    2011-11-01T23:59:59.000Z

    This proof-of-concept research was performed to explore the feasibility of using real-world braking data from commercial motor vehicles to make a diagnosis of brake condition similar to that of the performance-based brake tester (PBBT). This was done by determining the relationship between pressure and brake force (P-BF), compensating for the gross vehicle weight (GVW). The nature of this P-BF relationship (e.g., low braking force for a given brake application pressure) may indicate brake system problems. In order to determine the relationship between brake force and brake application pressure, a few key parameters of duty cycle information were collected. Because braking events are often brief, spanning only a few seconds, a sample rate of 10 Hz was needed. The algorithm under development required brake application pressure and speed (from which deceleration was calculated). Accurate weight estimation was also needed to properly derive the braking force from the deceleration. In order to ensure that braking force was the predominant factor in deceleration for the segments of data used in analysis, the data was screened for grade as well. Also, the analysis needed to be based on pressures above the crack pressure. The crack pressure is the pressure below which the individual brakes are not applied due the nature of the mechanical system. This value, which may vary somewhat from one wheel end to another, is approximately 10 psi. Therefore, only pressures 15 psi and above were used in the analysis. The Department of Energy s Medium Truck Duty Cycle research has indicated that under the real-world circumstances of the test vehicle brake pressures of up to approximately 30 psi can be expected. Several different types of data were collected during the testing task of this project. Constant-pressure stopping tests were conducted at several combinations of brake application pressure (15, 20, 25, and 30 psi), load conditions (moderately and fully laden), and speeds (20 and 30 mph). Data was collected at 10 Hz. Standard and stepped-pressure performance-based brake tests with brake pressure transducers were performed for each loading condition. The stepped-pressure test included the constant-pressure intervals of brake application at 15, 20, 25, and 30 psi. The PBBT data files included 10 Hz streaming data collected during the testing of each axle. Two weeks of real-world duty cycle (driving and braking) data was also collected at 10 Hz. Initial analysis of the data revealed that the data collected in the field (i.e., day-to-day operations) provided the same information as that obtained from the controlled tests. Analysis of the data collected revealed a strong linear relationship between brake application pressure and deceleration for given GVWs. As anticipated, initial speed was not found to be a significant factor in the deceleration-pressure relationship, unlike GVW. The positive results obtained from this proof of concept test point to the need for further research to expand this concept. A second phase should include testing over a wider range of speeds and include medium brake application pressures in addition to the low pressures tested in this research. Testing on multiple vehicles would also be of value. This future phase should involve testing to determine how degradation of braking performance affects the pressure-deceleration relationship.

  19. Combined hydraulic and regenerative braking system

    DOE Patents [OSTI]

    Venkataperumal, Rama R. (Troy, MI); Mericle, Gerald E. (Mount Clemens, MI)

    1981-06-02T23:59:59.000Z

    A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  20. Wheeled hopping robot

    DOE Patents [OSTI]

    Fischer, Gary J. (Albuquerque, NM)

    2010-08-17T23:59:59.000Z

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  1. Speciation of Sb in airborne particulate matter, vehicle brake linings, and brake pad wear residues

    E-Print Network [OSTI]

    Short, Daniel

    Speciation of Sb in airborne particulate matter, vehicle brake linings, and brake pad wear residues: XAS XANES EXAFS Antimony Particulate matter Brake linings a b s t r a c t Insights into the speciation of Sb in samples of brake linings, brake pad wear residues, road dust, and atmospheric particulate

  2. Regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1982-01-12T23:59:59.000Z

    Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

  3. Variable ratio regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15T23:59:59.000Z

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

  4. Finite element analysis of the effect of up-armouring on the off-road braking and sharp-turn performance

    E-Print Network [OSTI]

    Grujicic, Mica

    Finite element analysis of the effect of up-armouring on the off-road braking and sharp-mobility multi-purpose wheeled vehicle, off-road vehicle performance, finite element modelling and simulations revision for publication on 15 June 2009. DOI: 10.1243/09544070JAUTO1187 Abstract: A comprehensive finite

  5. Automatic Mechetronic Wheel Light Device

    DOE Patents [OSTI]

    Khan, Mohammed John Fitzgerald (Silver Spring, MD)

    2004-09-14T23:59:59.000Z

    A wheel lighting device for illuminating a wheel of a vehicle to increase safety and enhance aesthetics. The device produces the appearance of a "ring of light" on a vehicle's wheels as the vehicle moves. The "ring of light" can automatically change in color and/or brightness according to a vehicle's speed, acceleration, jerk, selection of transmission gears, and/or engine speed. The device provides auxiliary indicator lights by producing light in conjunction with a vehicle's turn signals, hazard lights, alarm systems, and etc. The device comprises a combination of mechanical and electronic components and can be placed on the outer or inner surface of a wheel or made integral to a wheel or wheel cover. The device can be configured for all vehicle types, and is electrically powered by a vehicle's electrical system and/or battery.

  6. Commercial Motor Vehicle Brake Assessment Tools

    E-Print Network [OSTI]

    Commercial Motor Vehicle Brake Assessment Tools Commercial Motor Vehicle Roadside Technology to deceleration in g's ­ Passing score: BE43.5 · Enforcement tool for only 3 years. · Based solely on brake Brake Research · CMVRTC research built on these enforcement tools ­ Correlation Study ­ Level-1 / PBBT

  7. Disturbance Control of the Hydraulic Brake in a Wind Turbine

    E-Print Network [OSTI]

    Yang, Zhenyu

    Disturbance Control of the Hydraulic Brake in a Wind Turbine Frank Jepsen, Anders Søborg brake in a wind turbine. Brake torque is determined by friction coefficient and clamp force; the latter brake is one1 of the two independent brake systems in a wind turbine. As a consequence of the gearing

  8. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM)

    1983-01-01T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  9. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1982-01-20T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  10. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-10-11T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

  11. Commercial Motor Vehicle Brake-Related Research

    E-Print Network [OSTI]

    Commercial Motor Vehicle Brake-Related Research Commercial Motor Vehicle Roadside Technology Corridor Safety Technology Showcase October 14, 2010 Commercial Motor Vehicle Roadside Technology Corridor

  12. Rim seal for turbine wheel

    DOE Patents [OSTI]

    Glezer, Boris (Del Mar, CA); Boyd, Gary L. (Alpine, CA); Norton, Paul F. (San Diego, CA)

    1996-01-01T23:59:59.000Z

    A turbine wheel assembly includes a disk having a plurality of blades therearound. A ceramic ring is mounted to the housing of the turbine wheel assembly. A labyrinth rim seal mounted on the disk cooperates with the ceramic ring to seal the hot gases acting on the blades from the disk. The ceramic ring permits a tighter clearance between the labyrinth rim seal and the ceramic ring.

  13. REPORT on the TRUCK BRAKE LINING WORKSHOP and FLEET OPERATORS' SURVEY

    SciTech Connect (OSTI)

    Blau, P.J.

    2003-02-03T23:59:59.000Z

    The report summarizes what transpired during brake linings-related workshop held at the Fall 2003 meeting of the Technology and Maintenance Council (TMC) in Charlotte, NC. The title of the workshop was ''Developing a Useful Friction Material Rating System''. It was organized by a team consisting of Peter Blau (Oak Ridge National Laboratory), Jim Britell (National Highway Traffic Safety Administration), and Jim Lawrence (Motor and Equipment Manufacturers Association). The workshop was held under the auspices of TMC Task Force S6 (Chassis), chaired by Joseph Stianche (Sanderson Farms, Inc.). Six invited speakers during the morning session provided varied perspectives on testing and rating aftermarket automotive and truck brake linings. They were: James R. Clark, Chief Engineer, Foundation Brakes and Wheel Equipment, Dana Corporation, Spicer Heavy Axle and Brake Division; Charles W. Greening, Jr, President, Greening Test Labs; Tim Duncan, General Manager, Link Testing Services;Dennis J. McNichol, President, Dennis NationaLease; Jim Fajerski, Business Manager, OE Sales and Applications Engineering, Federal Mogul Corporation; and Peter J. Blau, Senior Materials Development Engineer, Oak Ridge National Laboratory. The afternoon break-out sessions addressed nine questions concerning such issues as: ''Should the federal government regulate aftermarket lining quality?''; ''How many operators use RP 628, and if so, what's good or bad about it?''; and ''Would there be any value to you of a vocation-specific rating system?'' The opinions of each discussion group, consisting of 7-9 participants, were reported and consolidated in summary findings on each question. Some questions produced a greater degree of agreement than others. In general, the industry seems eager for more information that would allow those who are responsible for maintaining truck brakes to make better, more informed choices on aftermarket linings. A written fleet operator survey was also conducted during the TMC meeting. Twenty-one responses were received, spanning fleet sizes between 12 and 170,000 vehicles. Responses are summarized in a series of tables separated into responses from small (100 or fewer powered vehicles), medium (101-1000 vehicles), and large fleets (>1000 vehicles). The vast majority of fleets do their own brake maintenance, relying primarily on experience and lining manufactures to select aftermarket linings. At least half of the responders are familiar to some extent with TMC Recommended Practice 628 on brake linings, but most do not use this source of test data as the sole criterion to select linings. Significant shortfalls in the applicability of TMC RP 628 to certain types of brake systems were noted.

  14. Throttle And Brake Control Systems For Automatic Vehicle Following

    E-Print Network [OSTI]

    Ioannou, P.; Xu, Z.

    1994-01-01T23:59:59.000Z

    and Brake Control Systems for Automatic Vehicle Following P.and Brake Control Systems for Automatic Vehicle Following *Transit Systems, Proceedings of 1977 Joint Automatic Control

  15. Brake Defect Causation and Abatement Study (BDCAS)

    E-Print Network [OSTI]

    on various lining materials for comparison study #12;Center for Transportation Analysis 2360 CherahalaBrake Defect Causation and Abatement Study (BDCAS) Oak Ridge National Laboratory managed by UT Based Brake Testers (PBBTs) part of the out-of- service criterion for commercial motor vehicles in 2007

  16. TMV Technology Capabilities Brake Stroke Monitor

    E-Print Network [OSTI]

    TMV Technology Capabilities Brake Stroke Monitor Brake monitoring systems are proactive maintenance This technology allows for CMV operators to have knowledge of their steer, drive, and tandem axle group weights setup is required. Current Safety/Enforcement Technologies EOBR (electronic on-board recorder) On

  17. By moving the front wheels in and back wheels out, the rover can

    E-Print Network [OSTI]

    Withers, Paul

    . Solar arrays Provide power for driving the rover, operating the science instruments, heating. The images provided the sci- entists with their first glimpse of their home away from home -- an area they will study for months. Scientists are thrilled with what they have seen. "Home sweet home," says Steve

  18. Contactless magnetic brake for automotive applications

    E-Print Network [OSTI]

    Gay, Sebastien Emmanuel

    2009-05-15T23:59:59.000Z

    consumption due to power assistance, and requirement for anti-lock controls. To solve these problems, a contactless magnetic brake has been developed. This concept includes a novel flux-shunting structure to control the excitation flux generated by permanent...

  19. An engine air-brake integration study

    E-Print Network [OSTI]

    Mulchandani, Hiten

    2011-01-01T23:59:59.000Z

    The feasibility of operating an engine air-brake (EAB) integrated with a pylon duct bifurcation in a realistic aircraft engine environment has been analyzed. The EAB uses variable exit guide vanes downstream of a high ...

  20. Method and apparatus for wind turbine braking

    DOE Patents [OSTI]

    Barbu, Corneliu (Laguna Hills, CA); Teichmann, Ralph (Nishkayuna, NY); Avagliano, Aaron (Houston, TX); Kammer, Leonardo Cesar (Niskayuna, NY); Pierce, Kirk Gee (Simpsonville, SC); Pesetsky, David Samuel (Greenville, SC); Gauchel, Peter (Muenster, DE)

    2009-02-10T23:59:59.000Z

    A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

  1. Constraining the Braking Indices of Magnetars

    E-Print Network [OSTI]

    Gao, Z F; Wang, N; Yuan, J P; Peng, Q H; Du, Y J

    2015-01-01T23:59:59.000Z

    Due to the lack of long term pulsed emission in quiescence and the strong timing noise, it is impossible to directly measure the braking index $n$ of a magnetar. Based on the estimated ages of their potentially associated supernova remnants (SNRs), we estimate the values of $n$ of nine magnetars with SNRs, and find that they cluster in a range of $1\\sim$41. Six magnetars have smaller braking indices of $13$ for other three magnetars are attributed to the decay of external braking torque, which might be caused by magnetic field decay. We estimate the possible wind luminosities for the magnetars with $13$ within the updated magneto-thermal evolution models. We point out that there could be some connections between the magnetar's anti-glitch event and its braking index, and the magnitude of $n$ should be taken into account when explaining the event. Although the constrained range of the magnetars' braking indices is tentative, our method provides an effective way to constrain the magnetars' braking indices if th...

  2. Adaptive controller for regenerative and friction braking system

    DOE Patents [OSTI]

    Davis, Roy I. (Ypsilanti, MI)

    1990-01-01T23:59:59.000Z

    A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.

  3. Aerodynamic Drag Reduction Apparatus For Wheeled Vehicles In Ground Effect

    DOE Patents [OSTI]

    Ortega, Jason M. (Pacifica, CA); Salari, Kambiz (Livermore, CA)

    2005-12-13T23:59:59.000Z

    An apparatus for reducing the aerodynamic drag of a wheeled vehicle in a flowstream, the vehicle having a vehicle body and a wheel assembly supporting the vehicle body. The apparatus includes a baffle assembly adapted to be positioned upstream of the wheel assembly for deflecting airflow away from the wheel assembly so as to reduce the incident pressure on the wheel assembly.

  4. A diagnostic system for air brakes in commercial vehicles 

    E-Print Network [OSTI]

    Coimbatore Subramanian, Shankar Ram

    2007-09-17T23:59:59.000Z

    This dissertation deals with the development of a model-based diagnostic system for air brake systems that are widely used in commercial vehicles, such as trucks, tractor-trailers, buses, etc. The performance of these brake ...

  5. Bradbury Science Museum - Science on Wheels

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

    Bradbury Science Museum - Science on Wheels Our Mission: To stimulate interest in and enthusiasm for science, technology, engineering and mathematics and promote public...

  6. Energy Upgrade California Drives Demand From Behind the Wheel...

    Energy Savers [EERE]

    Upgrade California Drives Demand From Behind the Wheel Energy Upgrade California Drives Demand From Behind the Wheel Photo of a trailer with the Energy Upgrade California logo and...

  7. Neurobiological and Physiological Underpinnings of High Voluntary Wheel Running

    E-Print Network [OSTI]

    Kolb, Erik Mason

    2010-01-01T23:59:59.000Z

    for high voluntary wheel running. Physiol. Behav. 83, 515-for high voluntary wheel-running: effect on skeletal musclefor high endurance running increases hindlimb symmetry.

  8. The effect of friction on drum brakes

    SciTech Connect (OSTI)

    Huang, Y.M.; Shyr, J.S. [National Taiwan Univ. (China)

    1995-12-31T23:59:59.000Z

    The boundary element method (BEM) has been developed for a long period of time. Cruse and Wilson developed an isoparametric quadratic element. Rizzo, Cruse, Rizzo and Shippy, and Swedlow and cruse applied the method to various problems. It shows that the BEM can provide a very good analytical result in the linear problem and it can reduce time in preparation of numerical data. Watson and Newcomb pointed out that the pressure distribution on the contact surface of the brake drum and the lining plate do not vary significantly along the axis. The deflection can be reduced by an appropriate design of the web; therefore, two dimensional analysis with the BEM is used in this analysis. Based on the authors` knowledge, this is the first paper to analyze the drum brake by using the BEM. The assumptions are the brake drum to be a rigid body, perfect interface contact between the drum and the shoe, the constant friction coefficient of the friction material and the thermal effect to be neglected. The two dimensional equations are derived based on the Somigliana`s identity. Since there is no shape function and no need of the Jacobin for the coordinate transform, to integrate numerically is easier and to write a computer code is simpler for the constant value element than the second order element. The linear element is inappropriate to treat the comer problem. Using the linear elements or second order elements creates discontinuous phenomena along the irregular boundary. The common nodal point has different normal vector and boundary conditions. It is necessary to have an extra equation to provide a unique solution for the final linear equation. Using the constant value element can get rid of this problem. The effect of the friction on the pressure distribution at the friction interface is studied. The calculated results of the pressure distribution are compared with the available data. The mathematical model can be used as a design tool to predict the performance of drum brakes.

  9. Balancing a two-wheeled Segway robot

    E-Print Network [OSTI]

    Bageant, Maia R. (Maia Reynolds)

    2011-01-01T23:59:59.000Z

    In this thesis, I designed and constructed hardware for a two-wheeled balancing Segway robot. Because the robot could not be balanced based on a control system derived from the original analytical model, additional system ...

  10. A diagnostic system for air brakes in commercial vehicles

    E-Print Network [OSTI]

    Coimbatore Subramanian, Shankar Ram

    2007-09-17T23:59:59.000Z

    ]. It is appropriate to point out that, in an appraisal of the future needs of the trucking industry [16], the authors, who represent a broad spectrum of the trucking industry, call for the development of improved methods of brake inspections. 6 B. Objectives... States railway industry, air brake systems were initially introduced during the nineteenth century. Before the introduction of the air brake system, railway cars were retarded mainly by mechanical means (for example, by levers, chains and other linkages...

  11. Design, Modeling And Control Of Steering And Braking For An Urban Electric Vehicle

    E-Print Network [OSTI]

    Maciua, Dragos

    1996-01-01T23:59:59.000Z

    Design, Modeling and Control of Steering and Braking for anDesign, Modeling and Control of Steering and Braking for anDesign, Modeling and Control of Steering and Braking for an

  12. Measurement and control of brake pedal feel quality in automobile manufacturing

    E-Print Network [OSTI]

    Cerilles, Jeffrey T. (Jeffrey Thomas)

    2005-01-01T23:59:59.000Z

    Customer perception of brake pedal feel quality, as related to the perception of the brake pedal feeling soft or mushy, depends on both the customer's subjective judgment of quality and the actual build quality of the brake ...

  13. Pneumatic brake control for precision stopping of heavy-duty vehicles

    E-Print Network [OSTI]

    Bu, Fanping; Tan, Han-Shue

    2007-01-01T23:59:59.000Z

    desirable that the automatic brake control system uses thesystems,” IEEE Transactions on Automatic Control, vol. 41,enables automatic control of the pneumatic brake system and

  14. In-line drivetrain and four wheel drive work machine using same

    DOE Patents [OSTI]

    Hoff, Brian (East Peoria, IL)

    2008-08-05T23:59:59.000Z

    A four wheel drive articulated mine loader is powered by a fuel cell and propelled by a single electric motor. The drivetrain has the first axle, second axle, and motor arranged in series on the work machine chassis. Torque is carried from the electric motor to the back differential via a pinion meshed with the ring gear of the back differential. A second pinion oriented in an opposite direction away from the ring gear is coupled to a drive shaft to transfer torque from the ring gear to the differential of the front axle. Thus, the ring gear of the back differential acts both to receive torque from the motor and to transfer torque to the forward axle. The in-line drive configuration includes a single electric motor and a single reduction gear to power the four wheel drive mine loader.

  15. Pulsar Braking Index and Mass Accretion

    E-Print Network [OSTI]

    P. D. Morley

    1993-11-15T23:59:59.000Z

    I show that the braking index, $N$, a fundamental pulsar experimental quantity, naturally differs from the canonical value of 3 by terms which involve mass accretion. Using the measured values of $N$ for PSR1509-58 and PSR0531+21, I determine that for constant density neutron stars their present mass accretion rates are $(3.10\\pm.51)\\times10^{-5}$ M year$^{-1}$ and $(9.946\\pm.089)\\times10^{-5}$ M year$^{-1}$ respectively, where M is the mass of each pulsar. Finally, I demonstrate that mass accretion removes the outstanding problem of the origin of the big glitches of the Vela Pulsar.

  16. Do Si stars undergo any magnetic braking?

    E-Print Network [OSTI]

    P. North

    1998-02-23T23:59:59.000Z

    The old question of rotational braking of Ap Si stars is revisited on the empirical side, taking advantage of the recent Hipparcos results. Field stars with various evolutionary states are considered, and it is shown that the loose correlation between their rotational period and their surface gravity is entirely compatible with conservation of angular momentum. No evidence is found for any loss of angular momentum on the Main Sequence, which confirms earlier results based on less reliable estimates of surface gravity. The importance of reliable, fundamental Teff determinations of Bp and Ap stars is emphasized.

  17. Development of Diagnostic Algorithms for Air Brakes in Trucks

    E-Print Network [OSTI]

    Dhar, Sandeep

    2011-10-21T23:59:59.000Z

    causes a reduction in the steady-state pressure in the brake chamber and an increase in the lag of the braking pressure response thereby increasing the stopping distance of the vehicle. Currently a presence of leak in the system is detected...

  18. Braking system for use with an arbor of a microscope

    DOE Patents [OSTI]

    Norgren, Duane U. (Orinda, CA)

    1984-01-01T23:59:59.000Z

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling device causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  19. Front Burner- Issue 14

    Broader source: Energy.gov [DOE]

    The Cybersecurity Front Burner Issue No. 14 addresses the 2013 National Cybersecurity Awareness Month (NCSAM) Campaign and Phishing Scams.

  20. Front Burner- Issue 15

    Broader source: Energy.gov [DOE]

    The Cybersecurity Front Burner Issue No. 15 addresses the DOE eSCRM Program and Secure Online Shopping.

  1. Reconfigurable wheels : re-inventing the wheel for the next generation of planetary rovers

    E-Print Network [OSTI]

    Baker, Brittany, S.M. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Experiences with Spirit and Opportunity, the twin Mars Exploration Rovers, showed that one of the major issues that needs to be addressed in order to expand the exploration capabilities of planetary rovers is that of wheel ...

  2. New Phase-coherent Measurements of Pulsar Braking Indices

    E-Print Network [OSTI]

    Margaret A. Livingstone; Victoria M. Kaspi; Fotis P. Gavriil; Richard N. Manchester; E. V. Gotthelf; Lucien Kuiper

    2007-02-07T23:59:59.000Z

    Pulsar braking indices offer insight into the physics that underlies pulsar spin-down. Only five braking indices have been measured via phase-coherent timing; all measured values are less than 3, the value expected from magnetic dipole radiation. Here we present new measurements for three of the five pulsar braking indices, obtained with phase-coherent timing for PSRs J1846-0258 (n=2.65+/-0.01), B1509-58 (n=2.839+/-0.001) and B0540-69 (n=2.140+/-0.009). We discuss the implications of these results and possible physical explanations for them.

  3. Applied grinding wheel performance evaluation for optical fabrication

    SciTech Connect (OSTI)

    Piscotty, M.A.; Taylor, J.S.; Blaedel, K.L.

    1996-06-11T23:59:59.000Z

    We are collaborating with the Center for Optics Manufacturing (Rochester NY) to develop fine diamond grinding wheels for spherical grinding of glass optics. A standardized method for evaluating wheel performance includes in-process acoustic emission (AE). This paper includes recent AE measurements taken during the evaluation of several fine diamond grinding wheels and discusses how this new information might relate to the physical performance of the wheels. An interesting observation is also reported on the surface topography of worn bronze wheels using an interferometric profiler.

  4. Regenerative braking on bicycles to power LED safety flashers

    E-Print Network [OSTI]

    Collier, Ian M

    2005-01-01T23:59:59.000Z

    This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

  5. automotive drum brakes: Topics by E-print Network

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

    well-known phenomena of acoustics of friction as the squealing disc brake and the singing wine glass. Oleg N. Kirillov 2007-08-07 130 The Ultra-High Energy Cosmic Ray Spectrum...

  6. Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking

    E-Print Network [OSTI]

    Duffy, Ken

    Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking Selim Solmaz, switching, and tuning (MMST) paradigm [13, 14, 15] for preventing un­tripped rollover in automotive vehicles performance than its fixed robust counterpart. Keywords: Automotive control; Multiple models; Parameter

  7. Investigation of aerodynamic braking devices for wind turbine applications

    SciTech Connect (OSTI)

    Griffin, D.A. [R. Lynette & Associates, Seattle, WA (United States)

    1997-04-01T23:59:59.000Z

    This report documents the selection and preliminary design of a new aerodynamic braking system for use on the stall-regulated AWT-26/27 wind turbines. The goal was to identify and design a configuration that offered improvements over the existing tip brake used by Advanced Wind Turbines, Inc. (AWT). Although the design objectives and approach of this report are specific to aerodynamic braking of AWT-26/27 turbines, many of the issues addressed in this work are applicable to a wider class of turbines. The performance trends and design choices presented in this report should be of general use to wind turbine designers who are considering alternative aerodynamic braking methods. A literature search was combined with preliminary work on device sizing, loads and mechanical design. Candidate configurations were assessed on their potential for benefits in the areas of cost, weight, aerodynamic noise, reliability and performance under icing conditions. As a result, two configurations were identified for further study: the {open_quotes}spoiler-flap{close_quotes} and the {open_quotes}flip-tip.{close_quotes} Wind tunnel experiments were conducted at Wichita State University to evaluate the performance of the candidate aerodynamic brakes on an airfoil section representative of the AWT-26/27 blades. The wind tunnel data were used to predict the braking effectiveness and deployment characteristics of the candidate devices for a wide range of design parameters. The evaluation was iterative, with mechanical design and structural analysis being conducted in parallel with the braking performance studies. The preliminary estimate of the spoiler-flap system cost was $150 less than the production AWT-26/27 tip vanes. This represents a reduction of approximately 5 % in the cost of the aerodynamic braking system. In view of the preliminary nature of the design, it would be prudent to plan for contingencies in both cost and weight.

  8. Asbestos-free brake-lining materials for hydrogenerators

    SciTech Connect (OSTI)

    Lalonde, S.; Lanteigne, J. [Hydro-Quebec, Varennes, Quebec (Canada)

    1995-11-01T23:59:59.000Z

    Three different asbestos-free materials currently considered as new lining materials for hydrogenerator brakes were tested and compared to the original asbestos lining. Results show that these substitutes not only vary greatly from the original material in terms of mechanical properties and physical characteristics but also exhibit significantly different performances in braking tests. Consequently, these new materials are not entirely suitable for the intended application.

  9. Front Burner- Issue 13

    Broader source: Energy.gov [DOE]

    The Cybersecurity Front Burner Issue No. 13 contained a message from the Associate Chief Information Officer (ACIO) for Cybersecurity as well as a listing of recommended cybersecurity practices.

  10. Front Burner- Issue 18

    Broader source: Energy.gov [DOE]

    The Cybersecurity Front Burner Issue No. 18 addresses keeping kids safe on the Internet, cyber crime, and DOE Cyber awareness and training initiatives.

  11. Front Burner- Issue 16

    Broader source: Energy.gov [DOE]

    The Cybersecurity Front Burner Issue No. 16 addresses Malware, the Worst Passwords of 2013, and the Flat Stanley and Stop.Think.Connect. Campaign.

  12. Magnetic braking of T Tauri stars

    E-Print Network [OSTI]

    P. J. Armitage; C. J. Clarke

    1995-12-05T23:59:59.000Z

    We construct models for the rotation rates of T Tauri stars whose spin is regulated by magnetic linkage between the star and a surrounding accretion disc. Our models utilise a time-dependent disc code to follow the accretion process and include the effects of pre-main-sequence stellar evolution. We find that the initial disc mass controls the evolution of the star-disc system. For sufficiently massive discs, a stellar field of $\\sim$ 1 kG is able to regulate the spin rate to the observed values during the classical T Tauri phase. The field then acts to expel the disc and the star spins up at constant angular momentum as a weak-line system. Lower mass discs are ejected at an early epoch and fail to brake the star significantly. We extend the model to close binary systems, and find that the removal of angular momentum from the disc by the secondary significantly prolongs the inner disc lifetime. Such systems should therefore be relatively slow rotators. We also discuss the implications of our model for the spectral energy distributions and variability of T Tauri stars.

  13. A Wavelet-Based Methodology for Grinding Wheel Condition Monitoring

    SciTech Connect (OSTI)

    Liao, T. W. [Louisiana State University; Ting, C.F. [Louisiana State University; Qu, Jun [ORNL; Blau, Peter Julian [ORNL

    2007-01-01T23:59:59.000Z

    Grinding wheel surface condition changes as more material is removed. This paper presents a wavelet-based methodology for grinding wheel condition monitoring based on acoustic emission (AE) signals. Grinding experiments in creep feed mode were conducted to grind alumina specimens with a resinoid-bonded diamond wheel using two different conditions. During the experiments, AE signals were collected when the wheel was 'sharp' and when the wheel was 'dull'. Discriminant features were then extracted from each raw AE signal segment using the discrete wavelet decomposition procedure. An adaptive genetic clustering algorithm was finally applied to the extracted features in order to distinguish different states of grinding wheel condition. The test results indicate that the proposed methodology can achieve 97% clustering accuracy for the high material removal rate condition, 86.7% for the low material removal rate condition, and 76.7% for the combined grinding conditions if the base wavelet, the decomposition level, and the GA parameters are properly selected.

  14. abrasive grinding wheels: Topics by E-print Network

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

    with the Autonomous Intelligent Systems Group Behnke, Sven 426 ME 4171 --HOMEWORK: LIFE-CYCLE DESIGN WHEEL SYNOPSIS OF ASSIGNMENT Engineering Websites Summary: are Cokes in 12-pack...

  15. How to play a disc brake

    E-Print Network [OSTI]

    Oleg N. Kirillov

    2007-08-22T23:59:59.000Z

    We consider a gyroscopic system under the action of small dissipative and non-conservative positional forces, which has its origin in the models of rotating bodies of revolution being in frictional contact. The spectrum of the unperturbed gyroscopic system forms a "spectral mesh" in the plane "frequency -gyroscopic parameter" with double semi-simple purely imaginary eigenvalues at zero value of the gyroscopic parameter. It is shown that dissipative forces lead to the splitting of the semi-simple eigenvalue with the creation of the so-called "bubble of instability" - a ring in the three-dimensional space of the gyroscopic parameter and real and imaginary parts of eigenvalues, which corresponds to complex eigenvalues. In case of full dissipation with a positive-definite damping matrix the eigenvalues of the ring have negative real parts making the bubble a latent source of instability because it can "emerge" to the region of eigenvalues with positive real parts due to action of both indefinite damping and non-conservative positional forces. In the paper, the instability mechanism is analytically described with the use of the perturbation theory of multiple eigenvalues. As an example stability of a rotating circular string constrained by a stationary load system is studied in detail. The theory developed seems to give a first clear explanation of the mechanism of self-excited vibrations in the rotating structures in frictional contact, that is responsible for such well-known phenomena of acoustics of friction as the squealing disc brake and the singing wine glass.

  16. Tip-up and stabilization of an autonomous four-wheeled vehicle

    E-Print Network [OSTI]

    Lan, Justin T

    2011-01-01T23:59:59.000Z

    An instrumented four-wheeled robot was constructed to investigate steering-induced tip-up and rollover of four-wheeled vehicles, and the possibility of stabilizing and driving while balanced on two wheels. Using an analogy ...

  17. Control Engineering Practice 11 (2003) 163170 A mechatronic conception of a new intelligent braking system

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , residual friction, noise, vibrations, a new brake has been designed according to a modular principle which describes a new intelligent braking system for motor vehicles. A mechatronic approach helped to avoid some

  18. Evaluation of driver braking performance to an unexpected object in the roadway 

    E-Print Network [OSTI]

    Picha, Dale Louis

    1994-01-01T23:59:59.000Z

    components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...

  19. Evaluation of driver braking performance to an unexpected object in the roadway

    E-Print Network [OSTI]

    Picha, Dale Louis

    1994-01-01T23:59:59.000Z

    components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...

  20. Wheeling, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown ofNationwideWTED JumpHills,2732°,WetzelTechnologies IncEnergyWheeling,

  1. Regenerative braking device with rotationally mounted energy storage means

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1982-03-16T23:59:59.000Z

    A regenerative braking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.

  2. Evaluation of Corrosion Failure in Tractor-Trailer Brake System

    SciTech Connect (OSTI)

    Wilson, DF

    2002-10-22T23:59:59.000Z

    As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table/lining interface. The corrosion is non-uniform as is to be expected for plain carbon steel in chloride environments. This initial analysis found no evidence for the chlorides of calcium and magnesium, which are the newly introduced deicing and antiicing compounds and are less soluble in water than the identified chlorides of sodium and potassium, in the scale. The result could be as a result of non-exposure of the examined brake table to calcium and magnesium chloride. The mechanisms for the increased failure rate are postulated as being an increased rate of corrosion due to positive shifts in the corrosion potential, and an increased amount of corrosion due to an increased ''time of wetness'' that results from the presence of hygroscopic salts. Laboratory scale evaluation of the corrosion of plain carbon steel in simulated deicing and anti-icing solutions need to be performed to determine corrosion rates and morphological development of corrosion product, to compare laboratory data to in-service data, and to rank economically feasible replacement materials for low carbon steel. In addition, the mechanical behavior of the lining attached to the brake shoe table needs to be assessed. It is opined that an appropriate adjustment of materials could easily allow for a doubling of a brake table/lining lifetime. Suggestions for additional work, to clarify the mechanisms of rust jacking and to develop possible solutions, are described.

  3. Calibration, Information, and Control Strategies for Braking to Avoid a Collision

    E-Print Network [OSTI]

    effect. A new model is introduced according to which braking is controlled by keeping the perceived idealCalibration, Information, and Control Strategies for Braking to Avoid a Collision Brett R. Fajen Rensselaer Polytechnic Institute This study explored visual control strategies for braking to avoid collision

  4. Airbus A320 Braking as Predicate-Action Peter B. Ladkin

    E-Print Network [OSTI]

    Ladkin, Peter B.

    Airbus A320 Braking as Predicate-Action Diagrams Peter B. Ladkin Universit¨at Bielefeld, Technische of the Airbus A320 braking systems contained in the Flight Crew Operating Manual. This helps identify to interest us and others in the design of the A320 braking system [FI.93a, FI.93b, FI.93c]. This paper

  5. The design process for wheel-robot integration

    E-Print Network [OSTI]

    Carvajal, Michael Angelo

    2009-01-01T23:59:59.000Z

    In this thesis, the design process for wheel-robot integration was documented and reflected on. The project focused on redesigned certain aspects a half-scale wheel-robot to be integrated with a half-scale CityCar prototype ...

  6. WHEELS: A CONVERSATIONAL SYSTEM IN THE AUTOMOBILE CLASSIFIEDS DOMAIN

    E-Print Network [OSTI]

    WHEELS: A CONVERSATIONAL SYSTEM IN THE AUTOMOBILE CLASSIFIEDS DOMAIN Helen Meng, Senis WHEELS is a conversational system which provides access to a database of eletronic automobile classified users to search through a database of 5,000 automobile classifieds. The current end-to-end system can re

  7. Optimal planning and control for hazard avoidance of front-wheel steered ground vehicles

    E-Print Network [OSTI]

    Peters, Steven C. (Steven Conrad)

    2012-01-01T23:59:59.000Z

    Hazard avoidance is an important capability for safe operation of robotic vehicles at high speed. It is also an important consideration for passenger vehicle safety, as thousands are killed each year in passenger vehicle ...

  8. Oxygen-Diffused Titanium as a Candidate Brake Rotor Material

    SciTech Connect (OSTI)

    Qu, Jun [ORNL; Blau, Peter Julian [ORNL; Jolly, Brian C [ORNL

    2009-01-01T23:59:59.000Z

    Titanium alloys are one of several candidate materials for the next generation of truck disk brake rotors. Despite their advantages of lightweight relative to cast iron and good strength and corrosion resistance, titanium alloys are unlikely to be satisfactory brake rotor materials unless their friction and wear behavior can be significantly improved. In this study, a surface engineering process oxygen diffusion was applied to titanium rotors and has shown very encouraging results. The oxygen diffused Ti-6Al-4V (OD-Ti) was tested on a sub-scale brake tester against a flat block of commercial brake lining material and benchmarked against several other Ti-based materials, including untreated Ti-6Al-4V, ceramic particle-reinforced Ti composites (MMCs), and a thermal-spray-coated Ti alloy. With respect to friction, the OD-Ti outperformed all other candidate materials under the imposed test conditions with the friction coefficient remaining within a desirable range of 0.35-0.50, even under the harshest conditions when the disk surface temperature reached nearly 600 ?C. In addition, the OD-Ti showed significantly improved wear-resistance over the non-treated one and was even better than the Ti-based composite materials.

  9. automotive brake materials: Topics by E-print Network

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

    brake materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Multidisciplinary design optimization...

  10. aircraft brake materials: Topics by E-print Network

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

    brake materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 26 REDUCTION OF CADMTUM PLATING ON...

  11. Brake Wear and Performance Test Final December 2009

    E-Print Network [OSTI]

    Brake Wear and Performance Test Final Report December 2009 #12;FOREWORD This study focuses on using with assisting the State of Tennessee in identifying suitable PBBT machines, procuring a PBBT machine, installing the PBBT machine to be used in this research, and training Tennessee Department of Safety (TDOS) Staff

  12. Many applications require brakes, for instance to decelerate or to

    E-Print Network [OSTI]

    an error occurs in the process of a robotic arm. The energy consumption and actuation force of these brakes is very high. A team of TU Delft scientists developed a method to reduce the energy consumption. The energy consumption is high because an actuator has to generate a normal force between two friction

  13. Braking index of isolated pulsars: open questions and ways forward

    E-Print Network [OSTI]

    Hamil, Oliver

    2015-01-01T23:59:59.000Z

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate, the commonly accepted view is that it arises either through emission of magnetic dipole radiation (MDR) from a rotating magnetized body, through emission of a relativistic particle wind, or via higher order magnetic multipole or gravitational quadrupole radiation. The calculated energy loss by a rotating pulsar is model dependent and leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The theoretical value for braking index is $n = 1, 3, 5$ for wind, MDR, quadrupole radiation respectively. The accepted view is that pulsar braking is strongly dominated by MDR. Highly precise observations of isolated pulsars yield braking index values in the range $1 < n < 2.8$ which are consistently less than the value pred...

  14. TOWARDS GLOBAL CHASSIS CONTROL BY INTEGRATING THE BRAKE AND

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . Szab´o*, J. Bokor*, C. Poussot-Vassal**, O. Sename**, L. Dugard** *Computer and Automation Research active suspensions and an active brake is proposed to improve the safety of vehicles. The design is based of the method is demonstrated through a complex simulation example containing vehicle maneuvers. Keywords: LPV

  15. Heavy and Overweight Vehicle Brake Testing: Five-Axle Combination Tractor-Flatbed Final Report

    SciTech Connect (OSTI)

    Lascurain, Mary Beth [ORNL; Capps, Gary J [ORNL; Franzese, Oscar [ORNL

    2013-10-01T23:59:59.000Z

    The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data revealed a linear relationship between brake application pressure and was used to develop an algorithm to normalize stopping data for weight and initial speed.

  16. Characterization of grinding wheels: An annotated Bibliography. Final report

    SciTech Connect (OSTI)

    McClung, R.W.

    1995-12-01T23:59:59.000Z

    The characteristics of grinding wheels, after both fabrication and periods of operation, have a significant effect on the processed surface and the mechanical properties of advanced ceramics. An extensive literature survey and review has been conducted to determine and catalogue the various characterization methods that have been investigated and reported. Although many of the references have addressed the grinding of metals, the historical and technical merit justify their inclusion in this bibliography. For convenience, the references have been subdivided into nine subheadings: Nondestructive examination; elasticity and stiffness; wheel hardness; topography and profilometry; observation of texture of wheel surfaces wheel wear; in process monitoring of grinding, acoustic emission, other; characteristics of ground surfaces; and miscellaneous.

  17. Development of Diagnostic Algorithms for Air Brakes in Trucks 

    E-Print Network [OSTI]

    Dhar, Sandeep

    2011-10-21T23:59:59.000Z

    and the rear brake chamber using the predicted primary circuit pressure : : : : : : : : : : : : : : : : : : : : 54 33 Simulated response of the hybrid system : : : : : : : : : : : : : : : : 64 34 Steady-state estimate of z1 of the pneumatic hybrid system... with massless piston : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 67 xii FIGURE Page 35 Steady-state estimates of z1 and z2 of the pneumatic hybrid system : 70 36 (a) Mechanical hybrid system, (b) non-hybrid counterpart : : : : : : 70 37...

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

    SciTech Connect (OSTI)

    Peter J. Blau

    2000-04-26T23:59:59.000Z

    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.

  19. A mathematical model for air brake systems in the presence of leaks

    E-Print Network [OSTI]

    Ramaratham, Srivatsan

    2008-10-10T23:59:59.000Z

    of the pneumatic subsystem. . . . . . . . . . . . . . . . . . 20 16 Pressure transients at 722 kPa (90 psi) supply pressure with no leak. 22 17 Schematic of the setup for leak corroboration tests. . . . . . . . . . . 27 18 Comparison of measured and predicted mass... of detecting and locating leaks[6]. Most of the performance tests and visual based inspection tests of the air brake system indirectly correlate pressure in the brake chamber with the torque output, brake pad temperature, push rod strokes etc[7], [8]. More...

  20. AB-Net Method of Protection from Projectiles (city, military base, battle-front, etc.)

    E-Print Network [OSTI]

    Alexander Bolonkin

    2008-02-13T23:59:59.000Z

    The author suggests a low cost special AB-Net from artificial fiber, which may protect cities and important objects from rockets, artillery and mortar shells, projectiles, bullets, and strategic weapons. The idea is as follows: The offered AB-Net joins an incoming projectile to a small braking parachute and this incoming projectile loses speed by air braking after a drag distance of 50 - 150 meters. A following interception net after the first may serve to collect the slowed projectiles and their fragments or bomblets so that they do not reach the aimpoint. The author offers the design of AB-Net, a developed theory of snagging with a small braking parachute by AB-Net; and sample computations. These nets may be used for defense of a town, city, military base, battle-front line, road (from terrorists), or any important objects or installations (for example nuclear electric station, government buildings, etc.). Computed projects are: Net to counter small rockets (for example, from Qassam), net to counter artillery projectile (caliber 76 mm), net to counter bullets (caliber 7.6 mm). The offered method is cheaper by thousands of times than protection of a city by current anti-rocket systems. Discussion and results are at the end of the article. Key words: Protection from missile and projectile weapons, mortar, rocket, AB-Net, Qassam defense, incoming defense, armor.

  1. ARM - Front Page

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m DocumentationJanuary 9, 2009 [Events, Feature StoriesgovCampaignsSurfacegovFront Page

  2. From the front

    SciTech Connect (OSTI)

    Price, Stephen [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    The causes of recent dynamic thinning of Greenland's outlet glaciers have been debated. Realistic simulations suggest that changes at the marine fronts of these glaciers are to blame, implying that dynamic thinning will cease once the glaciers retreat to higher ground. For the last decade, many outlet glaciers in Greenland that terminate in the ocean have accelerated, thinned, and retreated. To explain these dynamic changes, two hypotheses have been discussed. Atmospheric warming has increased surface melting and may also have increased the amount of meltwater reaching the glacier bed, increasing lubrication at the base and hence the rate of glacier sliding. Alternatively, a change in the delicate balance of forces where the glacier fronts meet the ocean could trigger the changes. Faezeh Nick and colleagues5 present ice-sheet modeling experiments that mimic the observations on Helheim glacier, East Greenland, and suggest that the dynamic behaviour of outlet glaciers follows from perturbations at their marine fronts. Greenland's ice sheet loses mass partly through surface melting and partly through fast flowing outlet glaciers that connect the vast plateau of inland ice with the ocean. Earlier ice sheet models have failed to reproduce the dynamic variability exhibited by ice sheets over time. It has therefore not been possible to distinguish with confidence between basal lubrication from surface meltwater and changes at the glaciers' marine fronts as causes for the observed changes on Greenland's outlet glaciers. But this distinction bears directly on future sea-level rise, the raison d'etre of much of modern-day glaciology: If the recent dynamic mass loss Greenland's outlet glaciers is linked to changing atmospheric temperatures, it may continue for as long as temperatures continue to increase. On the other hand, if the source of the dynamic mass loss is a perturbation at the ice-ocean boundary, these glaciers will lose contact with that perturbation after a finite amount of thinning and retreat. Therefore, the first hypothesis implies continued retreat of outlet glaciers into the foreseeable future, while the second does not -- provided the bedrock topography prohibits a connection between the retreating glacier and the ocean. Nick and coauthors test the physical mechanisms implied in each hypotbesis in an innovative ice-flow model, and use that model to try to match a time series of observations from Helheim glacier, one of Greenland's three largest outlet glaciers. Along with many observations, the simulations strongly support the contention that the recent retreat of Greenland's outlet glaciers is the result of changes at their marine fronts.Further, the simulations confirm the earlier hypotheses that bedrock topography largely controlled Helheim glacier's rapid acceleration and retreat in 2004 and 2005, and its deceleration and stabilization in 2006. Finally, the current work implies that if requirements of observational data (high-resolution bed topography) and computational resources (fine computational grid resolution) can be met, improved predictive capability for ice-sheet models is attainable. With respect to the concerns raised by the IPCC, this study signals progress.

  3. Vehicle yaw control via coordinated use of steering/braking systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Vehicle yaw control via coordinated use of steering/braking systems M. Doumiati, O. Sename, J.sename@gipsa-lab.grenoble-inp.fr) Computer and Automation Research Institute, Hungarian Academy of Sciences, Kende u. 13-17, H-1111, Budapest with steer- ing/braking coordination task for vehicle yaw control. For steerability enhancement, only active

  4. Modeling the pneumatic subsystem of a S-cam air brake system 

    E-Print Network [OSTI]

    Coimbatore Subramanian, Shankar

    2004-09-30T23:59:59.000Z

    The air brake system is one of the critical components in ensuring the safe operation of any commercial vehicle. This work is directed towards the development of a fault-free model of the pneumatic subsystem of the air brake system. This model can...

  5. Modeling the pneumatic relay valve of an s-cam air brake 

    E-Print Network [OSTI]

    Vilayannur Natarajan, Shankar

    2005-08-29T23:59:59.000Z

    by the driver, when there are no faults or defects in the brake system. This thesis is aimed at modeling and experimentally corroborating a subsystem of an air brake system, namely the pneumatic relay valve. The pneumatic relay valve takes a input signal from...

  6. Fault tolerant control of automatically controlled vehicles in response to brake system failures 

    E-Print Network [OSTI]

    Hsien, Li-Wei

    1998-01-01T23:59:59.000Z

    in the brake system is vital. In this thesis, nonlinear failure detection filters are used for fault detection of sensors and actuators in a class of nonlinear systems. In this thesis, the effects of brake system failures in an AHS where the vehicle steering...

  7. Fault tolerant control of automatically controlled vehicles in response to brake system failures

    E-Print Network [OSTI]

    Hsien, Li-Wei

    1998-01-01T23:59:59.000Z

    in the brake system is vital. In this thesis, nonlinear failure detection filters are used for fault detection of sensors and actuators in a class of nonlinear systems. In this thesis, the effects of brake system failures in an AHS where the vehicle steering...

  8. Emission Factor for Antimony in Brake Abrasion Dusts as One of the

    E-Print Network [OSTI]

    Short, Daniel

    originating from automobiles. Abrasion dusts from commercially available brake pads (nonasbestos organic type factors originating from automobiles were approximately 32 µg Sb/braking/car for PM10 and 22 µg Sb of automobiles to the atmospheric Sb concen- tration. The emission factors of pollutants from automobiles have

  9. Well-to-Wheels Energy Use and Greenhouse Gas Emissions of Plug...

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

    Well-to-Wheels Energy Use and Greenhouse Gas Emissions of Plug-In Hybrid Electric Vehicles Well-to-Wheels Energy Use and Greenhouse Gas Emissions of Plug-In Hybrid Electric...

  10. The Genetic Architecture of High Voluntary Wheel Running in House Mice

    E-Print Network [OSTI]

    Hannon, Robert Michael

    2010-01-01T23:59:59.000Z

    for high voluntary wheel running. J. Exper. Biol. 212, 238-A. , Garland, T. Jr. (2009). Running behavior and its energyfor high voluntary wheel-running. Behav. Genet. 31, 309-316.

  11. Well-to-Wheels Analysis of Advanced Fuel/Vehicle Systems - A...

    Energy Savers [EERE]

    Well-to-Wheels Analysis of Advanced FuelVehicle Systems - A North American Study of Energy Use, Greenhouse Gas Emissions, and Criteria Pollutant Emissions Well-to-Wheels Analysis...

  12. A FINITE ELEMENT APPROACH FOR SIMULATING THE QUENCHING OF LARGE ALUMINIUM COMPRESSOR WHEELS

    E-Print Network [OSTI]

    A FINITE ELEMENT APPROACH FOR SIMULATING THE QUENCHING OF LARGE ALUMINIUM COMPRESSOR WHEELS A FINITE ELEMENT APPROACH FOR SIMULATING THE QUENCHING OF LARGE ALUMINIUM COMPRESSOR WHEELS Dirk Büche Aluminum devices such as compressor wheels are typically heat treated in order to achieve the required

  13. Quasi-Static Analysis of a Leg-Wheel Hybrid Vehicle for Enhancing Stair Climbing Ability

    E-Print Network [OSTI]

    Laksanacharoen, Sathaporn

    Quasi-Static Analysis of a Leg-Wheel Hybrid Vehicle for Enhancing Stair Climbing Ability Pattaramon}@kmutt.ac.th stl@kmitnb.ac.th Abstract - This paper presents quasi-static analysis of a leg- wheel hybrid vehicle. Index Terms - Leg-Wheel hybrid vehicle, Stair climbing ability, Quasi-static analysis I. INTRODUCTION

  14. KINEMATIC CONTROL OF A NONHOLONOMIC WHEELED MOBILE MANIPULATOR A DIFFERENTIAL FLATNESS APPROACH

    E-Print Network [OSTI]

    Krovi, Venkat

    the terminal conditions in the flat output space while control design reduces to a pole-placement problem) electro-mechanical testing. NOMENCLATURE WMR Wheeled Mobile Robot WMM Wheeled Mobile Manipulator ( ),x y Cartesian coordinates of the center of the wheel axle of the WMR Orientation of the WMR with respect

  15. Wind turbine trailing-edge aerodynamic brake design

    SciTech Connect (OSTI)

    Quandt, G.

    1996-01-01T23:59:59.000Z

    This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.

  16. POWER AND CONTROL WHEELPOWER AND CONTROL WHEEL AND THREATS

    E-Print Network [OSTI]

    Su, Xiao

    physical VIOLENCE sexual POWER AND CONTROL WHEELPOWER AND CONTROL WHEEL POWER AND CONTROL COERCION's life and circumstances. The Power & Control diagram is a particularly helpful tool in understanding for abusive behavior. Saying she caused it. ISOLATION: Controlling what she does, who she sees and talks to

  17. Electric Power Controller for Steering Wheel Management in Electric Cars

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Electric Power Controller for Steering Wheel Management in Electric Cars Vicente Milanés, Joshué. An electric car has been equipped with the system designed and tests to prove the behavior of the system transportation systems. Among these topics, the automation of the actuators involved in the management of a car

  18. Hydrodynamic Tesla Wheel Flume for Model and Prototype Testing

    E-Print Network [OSTI]

    Wood, Stephen L.

    The Tesla turbine, U.S. Patent 1,061,206 -- May 6, 1913 was invented by Nikola Tesla as a means to extractHydrodynamic Tesla Wheel Flume for Model and Prototype Testing Spencer Jenkins, Chris Scott, Jacob Engineering department at Florida Institute of Technology (Florida Tech) has developed a Hydrodynamic Tesla

  19. FULL FUEL CYCLE ASSESSMENT WELL TO WHEELS ENERGY INPUTS,

    E-Print Network [OSTI]

    FULL FUEL CYCLE ASSESSMENT WELL TO WHEELS ENERGY INPUTS, EMISSIONS, AND WATER IMPACTS Preparation for the AB 1007 (Pavley) Alternative Transportation Fuels Plan Proceeding Prepared For: California Energy, Project Manager Ray Tuvell, Manager EMERGING FUELS & TECHNOLOGY OFFICE Rosella Shapiro, Deputy Director

  20. Cold Fronts in CDM clusters

    E-Print Network [OSTI]

    Daisuke Nagai; Andrey V. Kravtsov

    2003-01-08T23:59:59.000Z

    Recently, high-resolution Chandra observations revealed the existence of very sharp features in the X-ray surface brightness and temperature maps of several clusters (Vikhlinin et. al., 2001). These features, called ``cold fronts'', are characterized by an increase in surface brightness by a factor >2 over 10-50 kpc, accompanied by a drop in temperature of a similar magnitude. The existence of such sharp gradients can be used to put interesting constraints on the physics of the intracluster medium (ICM), if their mechanism and longevity are well understood. Here, we present results of a search for cold fronts in high-resolution simulations of galaxy clusters in cold dark matter (CDM) models. We show that sharp gradients with properties similar to those of observed cold fronts naturally arise in cluster mergers when the shocks heat gas surrounding the merging sub-cluster, while its dense core remains relatively cold. The compression induced by supersonic motions and shock heating during the merger enhance the amplitude of gas density and temperature gradients across the front. Our results indicate that cold fronts are non-equilibrium transient phenomena and can be observed for a period of less than a billion years. We show that the velocity and density fields of gas surrounding the cold front can be very irregular which would complicate analyses aiming to put constraints on the physical conditions of the intracluster medium in the vicinity of the front.

  1. Innovative grinding wheel design for cost-effective machining of advanced ceramics. Phase I, final report

    SciTech Connect (OSTI)

    Licht, R.H.; Ramanath, S.; Simpson, M.; Lilley, E.

    1996-02-01T23:59:59.000Z

    Norton Company successfully completed the 16-month Phase I technical effort to define requirements, design, develop, and evaluate a next-generation grinding wheel for cost-effective cylindrical grinding of advanced ceramics. This program was a cooperative effort involving three Norton groups representing a superabrasive grinding wheel manufacturer, a diamond film manufacturing division and a ceramic research center. The program was divided into two technical tasks, Task 1, Analysis of Required Grinding Wheel Characteristics, and Task 2, Design and Prototype Development. In Task 1 we performed a parallel path approach with Superabrasive metal-bond development and the higher technical risk, CVD diamond wheel development. For the Superabrasive approach, Task 1 included bond wear and strength tests to engineer bond-wear characteristics. This task culminated in a small-wheel screening test plunge grinding sialon disks. In Task 2, an improved Superabrasive metal-bond specification for low-cost machining of ceramics in external cylindrical grinding mode was identified. The experimental wheel successfully ground three types of advanced ceramics without the need for wheel dressing. The spindle power consumed by this wheel during test grinding of NC-520 sialon is as much as to 30% lower compared to a standard resin bonded wheel with 100 diamond concentration. The wheel wear with this improved metal bond was an order of magnitude lower than the resin-bonded wheel, which would significantly reduce ceramic grinding costs through fewer wheel changes for retruing and replacements. Evaluation of ceramic specimens from both Tasks 1 and 2 tests for all three ceramic materials did not show evidence of unusual grinding damage. The novel CVD-diamond-wheel approach was incorporated in this program as part of Task 1. The important factors affecting the grinding performance of diamond wheels made by CVD coating preforms were determined.

  2. Control of Sideslip and Yaw Rate inControl of Sideslip and Yaw Rate in 44--Wheel Steering CarsWheel Steering Cars

    E-Print Network [OSTI]

    Williamson, John

    ! "!!# Control of Sideslip and Yaw Rate inControl of Sideslip and Yaw Rate in 44--Wheel Steering Abstract A new steering control structure for cars equipped with 4-wheel steering is presented. This control structure is based on a simplified linear model that captures the main features of the lateral

  3. Method for controlling a vehicle with two or more independently steered wheels

    DOE Patents [OSTI]

    Reister, D.B.; Unseren, M.A.

    1995-03-28T23:59:59.000Z

    A method is described for independently controlling each steerable drive wheel of a vehicle with two or more such wheels. An instantaneous center of rotation target and a tangential velocity target are inputs to a wheel target system which sends the velocity target and a steering angle target for each drive wheel to a pseudo-velocity target system. The pseudo-velocity target system determines a pseudo-velocity target which is compared to a current pseudo-velocity to determine a pseudo-velocity error. The steering angle targets and the steering angles are inputs to a steering angle control system which outputs to the steering angle encoders, which measure the steering angles. The pseudo-velocity error, the rate of change of the pseudo-velocity error, and the wheel slip between each pair of drive wheels are used to calculate intermediate control variables which, along with the steering angle targets are used to calculate the torque to be applied at each wheel. The current distance traveled for each wheel is then calculated. The current wheel velocities and steering angle targets are used to calculate the cumulative and instantaneous wheel slip and the current pseudo-velocity. 6 figures.

  4. Shocks and cold fronts in galaxy clusters

    E-Print Network [OSTI]

    Maxim Markevitch; Alexey Vikhlinin

    2007-04-24T23:59:59.000Z

    Table of contents (abridged): COLD FRONTS Origin and evolution of merger cold fronts Cold fronts in cluster cool cores . . . Simulations of gas sloshing. Origin of density discontinuity. . . . Effect of sloshing on cluster mass estimates and cooling flows. Zoology of cold fronts COLD FRONTS AS EXPERIMENTAL TOOL Velocities of gas flows Thermal conduction and diffusion across cold fronts Stability of cold fronts . . . Rayleigh-Taylor instability. Kelvin-Helmholtz instability. Possible future measurements using cold fronts . . . Plasma depletion layer and magnetic field. Effective viscosity of ICM. SHOCK FRONTS AS EXPERIMENTAL TOOL Cluster merger shocks Mach number determination Front width Mach cone and reverse shock? Test of electron-ion equilibrium . . . Comparison with other astrophysical plasmas Shocks and cluster cosmic ray population . . . Shock acceleration. Compression of fossil electrons. . . . Yet another method to measure intracluster magnetic field.

  5. Hydrogen Pathways: Cost, Well-to-Wheels Energy Use, and Emissions...

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

    Well-to-Wheels Energy Use, and Emissions for the Current Technology Status of Seven Hydrogen Production, Delivery, and Distribution Scenarios Hydrogen Pathways: Cost,...

  6. Braking index of isolated uniformly rotating magnetized pulsars

    E-Print Network [OSTI]

    Hamil, Oliver; Urbanec, Martin; Urbancova, Gabriela

    2015-01-01T23:59:59.000Z

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate in detail, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of $\\Omega$. This relation leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The MDR model predicts $n$ exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of $n$, individually accurate to a few percent or better, in the range 1$ <$ n $ < $ 2.8, which is consi...

  7. Preliminary survey report: evaluation of brake-drum service controls at Pennsylvania Bureau of Vehicle Management, Vehicle Maintenance Division, Harrisburg, Pennsylvania

    SciTech Connect (OSTI)

    Van Wagenen, H.D.

    1987-03-01T23:59:59.000Z

    Exposure to asbestos during the servicing of brakes on state-owned vehicles at the Bureau of Vehicle Management Maintenance Division, Harrisburg, Pennsylvania, was investigated as part of a study of control technologies. Brakes had been serviced at this garage facility for the previous year using a BCE-1000 Clayton brake-cleaning unit, sized for cars, vans, and pickups. The brake-cleaning unit consisted of a transparent enclosure hood and a HEPA vacuum filter dust collector, designed to contain and collect all brake-lining dust during vehicular brake maintenance and replacement. The authors conclude that the Clayton BCE-1000 dust-control unit appeared to be effective in containing and collecting brake dust during all vehicular brake maintenance and replacement jobs in this situation.

  8. Design of an Anti-Lock Regenerative Braking System for a ...14 International Journal of Automotive Engineering Vol. 1, Number 2, June 2011

    E-Print Network [OSTI]

    Vaziri, Ashkan

    energy storage system and subsequently used for the propulsion, significantly reducing the vehicle the brake of a vehicle [1]. The total energy dissipated through braking during a typical urban area drive

  9. Coordination and partial decoupling in tracking control for wheeled mobile manipulators

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Coordination and partial decoupling in tracking control for wheeled mobile manipulators V. Padois'Azereix, 65016 Tarbes Cedex Abstract We consider tracking control for mobile manipulators built from a wheeled of manipulation, the user has to control the location (position and orientation) of the tool or the grip of his

  10. Functional test procedure, Fifth Wheel: SS-R42351, Issue D

    SciTech Connect (OSTI)

    NONE

    1994-07-12T23:59:59.000Z

    This report describes the equipment required for initial assembly/maintenance and inspection/resetting of the Fifth Wheel system. It also gives a step-by-step procedure for initial assembly/maintenance inspection and procedures for resetting the system and Eager-Pac installation. The Fifth Wheel system is associated with a tractor-type vehicle used for materials handling.

  11. Magnesium Front End Design and Development

    Broader source: Energy.gov (indexed) [DOE]

    by: Alan A. Luo and R. C. McCune Presented by: James Quinn, General Motors Unibody Architecture 3-piece Mg front end (bodyframe) USAMP AMD 603 - Magnesium Front End Design and...

  12. Ocean fronts trigger high latitude phytoplankton blooms

    E-Print Network [OSTI]

    Taylor, John R.

    Density fronts are ubiquitous features of the upper ocean. Here, numerical simulations show that restratification at fronts inhibits vertical mixing, triggering phytoplankton blooms in low-light conditions. The stability ...

  13. Operations & Maintenance Best Practices Guide: Front Matter

    Broader source: Energy.gov [DOE]

    Guide describes the front matter of the Operations and Maintenance Best Practices: a Guide to Achieving Operational Efficiency.

  14. On The Use of Eddy Current Brakes as Tunable, Fast Turn-On Viscous Dampers For Haptic Rendering

    E-Print Network [OSTI]

    Hayward, Vincent

    On The Use of Eddy Current Brakes as Tunable, Fast Turn-On Viscous Dampers For Haptic Rendering, linear dampers for haptic rendering using a prototype haptic device outfitted with eddy current brakes discuss the results from haptic experiments for rendering viscosity, virtual walls and virtual friction

  15. Initial results using Eddy Current Brakes as Fast Turn-on, Programmable Physical Dampers for Haptic Rendering

    E-Print Network [OSTI]

    Hayward, Vincent

    Initial results using Eddy Current Brakes as Fast Turn-on, Programmable Physical Dampers for Haptic Machines McGill University, Montr´eal, Qu´ebec, Canada ABSTRACT We demonstrate the use of eddy current propose an alternate method to create damping in a haptic interface that uses eddy current brakes. 2 EDDY

  16. Rotor bore and turbine rotor wheel/spacer heat exchange flow circuit

    DOE Patents [OSTI]

    Caruso, Philip M. (Selkirk, NY); Eldrid, Sacheverel Quentin (Saratoga Springs, NY); Ladhani, Azad A. (Niskayuna, NY); DeMania, Alan Richard (Niskayuna, NY); Palmer, Gene David (Clifton Park, NY); Wilson, Ian David (Clifton Park, NY); Rathbun, Lisa Shirley (Scotia, NY); Akin, Robert Craig (Schenectady, NY)

    2002-01-01T23:59:59.000Z

    In a turbine having closed-circuit steam-cooling passages about the rim of the rotor during steady-state operation, compressor discharge air is supplied to the rotor bore for passage radially outwardly into the wheel space cavities between the wheels and spacers. Communicating slots and channels in the spacers and wheels at circumferentially spaced positions enable egress of the compressor discharge air into the hot gas flow path. At turbine startup, cooling air flows through the closed-circuit steam passages to cool the outer rim of the rotor while compressor discharge air pre-warms the wheels and spacers. At steady-state, cooling steam is supplied in the closed-circuit steam-cooling passages and compressor discharge air is supplied through the bore and into the wheel space cavities to cool the rotor.

  17. Method for controlling a vehicle with two or more independently steered wheels

    DOE Patents [OSTI]

    Reister, David B. (Oak Ridge, TN); Unseren, Michael A. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A method (10) for independently controlling each steerable drive wheel (W.sub.i) of a vehicle with two or more such wheels (W.sub.i). An instantaneous center of rotation target (ICR) and a tangential velocity target (v.sup.G) are inputs to a wheel target system (30) which sends the velocity target (v.sub.i.sup.G) and a steering angle target (.theta..sub.i.sup.G) for each drive wheel (W.sub.i) to a pseudovelocity target system (32). The pseudovelocity target system (32) determines a pseudovelocity target (v.sub.P.sup.G) which is compared to a current pseudovelocity (v.sub.P.sup.m) to determine a pseudovelocity error (.epsilon.). The steering angle targets (.theta..sup.G) and the steering angles (.theta..sup.m) are inputs to a steering angle control system (34) which outputs to the steering angle encoders (36), which measure the steering angles (.theta..sup.m). The pseudovelocity error (.epsilon.), the rate of change of the pseudovelocity error ( ), and the wheel slip between each pair of drive wheels (W.sub.i) are used to calculate intermediate control variables which, along with the steering angle targets (.theta..sup.G) are used to calculate the torque to be applied at each wheel (W.sub.i). The current distance traveled for each wheel (W.sub.i) is then calculated. The current wheel velocities (v.sup.m) and steering angle targets (.theta..sup.G) are used to calculate the cumulative and instantaneous wheel slip (e, ) and the current pseudovelocity (v.sub.P.sup.m).

  18. Recycled brake linings as partial aggregate substitute in asphalt paving. Construction and final report. Report for July 1992-August 1996

    SciTech Connect (OSTI)

    Miller, P.A.; Sukley, R.

    1996-09-01T23:59:59.000Z

    The purpose of this project was to evaluate the performance of asphalt containing various percentages of brake lining as an aggregate, and compare its performance to that of normal asphalt containing natural aggregate. This project is an effort to explore alternate ways to use waste product. Four test section of FB-2 Modified mix containing brake lining materials were placed in July 1992 along with one control section on SR 3022 in Mercer county. To date all sections are performing satisfactory, and Brake linings should be recommended as a viable partial replacement of aggregate in bituminous materials. This study only considered the performance of only off-spec brake linings, therefore, any performance data or enviromental effects of placement of used brake material should be addressed.

  19. Neutron scattering residual stress measurements on gray cast iron brake discs

    SciTech Connect (OSTI)

    Spooner, S.; Payzant, E.A.; Hubbard, C.R. [and others

    1996-11-01T23:59:59.000Z

    Neutron diffraction was used to investigate the effects of a heat treatment designed to remove internal residual stresses in brake discs. It is believed that residual stresses may change the rate of deformation of the discs during severe braking conditions when the disc temperature is increased significantly. Neutron diffraction was used to map out residual strain distributions in a production disc before and after a stress-relieving heat treatment. Results from these neutron diffraction experiments show that some residual strains were reduced by as much as 400 microstrain by stress relieving. 5 refs., 5 figs., 1 tab.

  20. Classical and quantum Big Brake cosmology for scalar field and tachyonic models

    SciTech Connect (OSTI)

    Kamenshchik, A. Yu. [Dipartimento di Fisica e Astronomia and INFN, Via Irnerio 46, 40126 Bologna (Italy) and L.D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences, Kosygin str. 2, 119334 Moscow (Russian Federation); Manti, S. [Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy)

    2013-02-21T23:59:59.000Z

    We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models based on a tachyon-pseudo-tachyon field . It is shown that the effect of quantum avoidance is absent for the soft singularities of the Big Brake type while it is present for the Big Bang and Big Crunch singularities. Thus, there is some kind of a classical - quantum correspondence, because soft singularities are traversable in classical cosmology, while the strong Big Bang and Big Crunch singularities are not traversable.

  1. Achieving Consistent Maximum Brake Torque with Varied Injection Timing in a DI Diesel Engine

    E-Print Network [OSTI]

    Kroeger, Timothy H

    2013-09-19T23:59:59.000Z

    The brake torque of a direct-injection diesel engine is known to plateau over a range of injection timings. Injection timing affects the engine’s ignition delay and the fractions of fuel which burn in premixed and diffusion modes. Therefore...

  2. Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter Juan for an Electric Vehicle has been simulated. The purpose of this device is to allow higher accelerations, similar in shape and size to a Chevrolet S-10. This vehicle was already converted to an electric car

  3. A study of factors affecting foot movement time in a braking maneuver

    E-Print Network [OSTI]

    Berman, Andrea Helene

    1994-01-01T23:59:59.000Z

    The nature of foot movement time (MT) in an actual braking maneuver and in a stationary vehicle was investigated regarding the effects of age and gender of the driver and nature of the stimulus to which the driver was responding. ANOVAs showed...

  4. Apparatus and methods for aligning holes through wheels and spacers and stacking the wheels and spacers to form a turbine rotor

    DOE Patents [OSTI]

    Berry, Robert Randolph (Greenville, SC); Palmer, Gene David (Clifton Park, NY); Wilson, Ian David (Clifton Park, NY)

    2000-01-01T23:59:59.000Z

    A gas turbine rotor stacking fixture includes upstanding bolts for reception in aligned bolt holes in superposed aft disk, wheels and spacers and upstanding alignment rods received in openings of the disk, wheels and spacers during the rotor stacking assembly. The axially registering openings enable insertion of thin-walled tubes circumferentially about the rim of the rotor, with tight tolerances to the openings to provide supply and return steam for cooling buckets. The alignment rods have radial dimensions substantially less than their dimensions in a circumferential direction to allow for radial opening misalignment due to thermal expansion, tolerance stack-up and wheel-to-spacer mismatch due to rabbet mechanical growth. The circumferential dimension of the alignment rods affords tightly toleranced alignment of the openings through which the cooling tubes are installed.

  5. Numerical Analysis of the Channel Wheel Fresh Air Ventilator Under Frosting Conditions

    E-Print Network [OSTI]

    Gao, B.; Dong, Z.; Cheng, Z.; Luo, E.

    2006-01-01T23:59:59.000Z

    As new equipment, the channel wheel fresh air ventilator has become increasingly popular in recent years. However, when such equipment is operated under low ambient temperature in the freezing area in winter, the formation of frost on the outdoor...

  6. Development of legged, wheeled, and hybrid rover mobility models to facilitate planetary surface exploration mission analysis

    E-Print Network [OSTI]

    McCloskey, Scott H. (Scott Haddon)

    2007-01-01T23:59:59.000Z

    This work discusses the Mars Surface Exploration (MSE) tool and its adaptation to model rovers featuring legged, wheeled, and hybrid mobility. MSE is a MATLAB based systems engineering tool that is capable of rapidly ...

  7. Light-Front Holographic QCD

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; de Teramond, Guy F.; /Costa Rica U.

    2012-02-16T23:59:59.000Z

    The relation between the hadronic short-distance constituent quark and gluon particle limit and the long-range confining domain is yet one of the most challenging aspects of particle physics due to the strong coupling nature of Quantum Chromodynamics, the fundamental theory of the strong interactions. The central question is how one can compute hadronic properties from first principles; i.e., directly from the QCD Lagrangian. The most successful theoretical approach thus far has been to quantize QCD on discrete lattices in Euclidean space-time. Lattice numerical results follow from computation of frame-dependent moments of distributions in Euclidean space and dynamical observables in Minkowski spacetime, such as the time-like hadronic form factors, are not amenable to Euclidean lattice computations. The Dyson-Schwinger methods have led to many important insights, such as the infrared fixed point behavior of the strong coupling constant, but in practice, the analyses are limited to ladder approximation in Landau gauge. Baryon spectroscopy and the excitation dynamics of nucleon resonances encoded in the nucleon transition form factors can provide fundamental insight into the strong-coupling dynamics of QCD. New theoretical tools are thus of primary interest for the interpretation of the results expected at the new mass scale and kinematic regions accessible to the JLab 12 GeV Upgrade Project. The AdS/CFT correspondence between gravity or string theory on a higher-dimensional anti-de Sitter (AdS) space and conformal field theories in physical space-time has led to a semiclassical approximation for strongly-coupled QCD, which provides physical insights into its nonperturbative dynamics. The correspondence is holographic in the sense that it determines a duality between theories in different number of space-time dimensions. This geometric approach leads in fact to a simple analytical and phenomenologically compelling nonperturbative approximation to the full light-front QCD Hamiltonian 'Light-Front Holography'. Light-Front Holography is in fact one of the most remarkable features of the AdS/CFT correspondence. The Hamiltonian equation of motion in the light-front (LF) is frame independent and has a structure similar to eigenmode equations in AdS space. This makes a direct connection of QCD with AdS/CFT methods possible. Remarkably, the AdS equations correspond to the kinetic energy terms of the partons inside a hadron, whereas the interaction terms build confinement and correspond to the truncation of AdS space in an effective dual gravity approximation. One can also study the gauge/gravity duality starting from the bound-state structure of hadrons in QCD quantized in the light-front. The LF Lorentz-invariant Hamiltonian equation for the relativistic bound-state system is P{sub {mu}}P{sup {mu}}|{psi}(P)> = (P{sup +}P{sup -} - P{sub {perpendicular}}{sup 2})|{psi}(P)> = M{sup 2}|{psi}(P)>, P{sup {+-}} = P{sup 0} {+-} P{sup 3}, where the LF time evolution operator P{sup -} is determined canonically from the QCD Lagrangian. To a first semiclassical approximation, where quantum loops and quark masses are not included, this leads to a LF Hamiltonian equation which describes the bound-state dynamics of light hadrons in terms of an invariant impact variable {zeta} which measures the separation of the partons within the hadron at equal light-front time {tau} = x{sup 0} + x{sup 3}. This allows us to identify the holographic variable z in AdS space with an impact variable {zeta}. The resulting Lorentz-invariant Schroedinger equation for general spin incorporates color confinement and is systematically improvable. Light-front holographic methods were originally introduced by matching the electromagnetic current matrix elements in AdS space with the corresponding expression using LF theory in physical space time. It was also shown that one obtains identical holographic mapping using the matrix elements of the energy-momentum tensor by perturbing the AdS metric around its static solution. A gravity dual to QCD is not known, but th

  8. Nonlinear analysis of time series of vibration data from a friction brake: SSA, PCA, and MFDFA

    E-Print Network [OSTI]

    Nikolay K. Vitanov; Norbert P. Hoffmann; Boris Wernitz

    2014-10-23T23:59:59.000Z

    We use the methodology of singular spectrum analysis (SSA), principal component analysis (PCA), and multi-fractal detrended fluctuation analysis (MFDFA), for investigating characteristics of vibration time series data from a friction brake. SSA and PCA are used to study the long time-scale characteristics of the time series. MFDFA is applied for investigating all time scales up to the smallest recorded one. It turns out that the majority of the long time-scale dynamics, that is presumably dominated by the structural dynamics of the brake system, is dominated by very few active dimensions only and can well be understood in terms of low dimensional chaotic attractors. The multi-fractal analysis shows that the fast dynamical processes originating in the friction interface are in turn truly multi-scale in nature.

  9. Modeling the pneumatic relay valve of an s-cam air brake

    E-Print Network [OSTI]

    Vilayannur Natarajan, Shankar

    2005-08-29T23:59:59.000Z

    inspections. For example, defects like chafed hoses do not show pronounced effect in performance based tests. In the past only a few cases of air leak violations have been detected by the conventional performance based testers namely roller dynamometer... detected by the performance based system since they had a pronounced effect on the brake force. Reference [6] emphasizes on the need for a standardized, hand held diagnostic tool for improving the existing inspections. A model based, performance based diag...

  10. Variations in gear fatigue life for different wind turbine braking strategies

    SciTech Connect (OSTI)

    McNiff, B.P. (Second Wind, Inc., Somerville, MA (USA)); Musial, W.D. (Solar Energy Research Inst., Golden, CO (USA)); Errichello, R. (GEARTECH, Albany, CA (USA))

    1991-06-01T23:59:59.000Z

    A large number of gearbox failures have occurred in the wind industry in a relatively short period, many because service loads were underestimated. High-torque transients that occur during starting and stopping are difficult to predict and may be overlooked in specifying gearbox design. Although these events comprise a small portion of total load cycles, they can be the most damaging. The severity of these loads varies dramatically with the specific configuration of the wind turbine. The large number of failures in Danish-designed Micon 65 wind turbines prompted this investigation. The high-speed and low-speed shaft torques were measured on a two-stage helical gearbox of a single Micon 65 turbine. Transient events and normal running loads were combined statistically to obtain a typical annual load spectrum. The pitting and bending fatigue lives of the gear teeth were calculated by using Miner's rule for four different high-speed shaft brake configurations. Each breaking scenario was run for both a high- and a low-turbulence normal operating load spectrum. The analysis showed increases in gear life by up to a factor of 25 when the standard high-speed shaft brake is replaced with a dynamic brake or modified with a damper. 9 refs., 9 figs., 3 tabs.

  11. Pressure transient method for front tracking

    SciTech Connect (OSTI)

    Benson, S.M.; Bodvarsson, G.S.

    1983-08-01T23:59:59.000Z

    A pressure transient technique for tracking the advance of cold water fronts during water flooding and goethermal injection operations has been developed. The technique is based on the concept that the steady state pressure buildup in the reservoir region inside the front can be calculated by a fluid skin factor. By analyzing successive pressure falloff tests, the advance of the front in the reservoir can be monitored. The validity of the methods is demonstrated by application to three numerically simulated data sets, a nonisothermal step-rate injection test, a series of pressure falloffs in a multilayered reservoir, and a series of pressure falloff tests in a water flooded oil reservoir.

  12. Back Cover Front Cover Office of Continuing

    E-Print Network [OSTI]

    Goodman, Robert M.

    Back Cover Front Cover Office of Continuing Professional Education 2012­2013 Professional Landscape of Golf Course Irrigation Systems (p. 13) · Basics of Turf Management (p. 21) · Turfgrass Establishment (p

  13. COLORADO FRONT RANGE SEISMICITY AND SEISMIC HAZARD

    E-Print Network [OSTI]

    Sheehan, Anne F.

    COLORADO FRONT RANGE SEISMICITY AND SEISMIC HAZARD Anne F. Sheehan University of Colorado, seismic, seismicity, crust, fault, hazard ABSTRACT Construction of seismic hazard and risk maps depends upon carefully constrained input parameters including background seismicity, seismic attenuation

  14. Light front Casimir effect at finite temperature

    E-Print Network [OSTI]

    P. L. M. Rodrigues; Silvana Perez; Danilo T. Alves; Van Sérgio Alves; Charles R. Silva

    2015-01-06T23:59:59.000Z

    The correct description of the standard Casimir effect for periodic boundary conditions via light front formalism implies in these conditions imposed at fixed Minkowski times [Almeida {\\it et al.} Phys. Rev. {\\bf D 87}, 065028 (2013); Chabysheva and Hiller, Phys. Rev. {\\bf D 88}, 085006 (2013)] instead of fixed light front times. The unphysical nature of this latter condition is manifested in the vacuum part by no regularization yielding a finite Casimir energy density [Lenz and Steinbacher, Phys. Rev. {\\bf D 67}, 045010 (2003)]. In the present paper, we extend this discussion and analyze the problem of the light front quantization with simultaneous presence of a thermal bath and boundary conditions. Considering both the oblique light front as well as Dirac light front coordinates, we show that the imposition of periodic boundary conditions at fixed Minkowski times recovers the expected behaviors for the energy density and Casimir entropy. We also investigate how the unphysical nature of the periodic boundary conditions imposed at fixed light front times manifests in the thermal part of the energy and entropy, showing that in the classical limit the Casimir entropy decreases linearly with the temperature (not becoming independent of the temperature as expected), and also that the Kirchhoff theorem is not respected.

  15. A unified framework for reactive control of wheeled mobile manipulators V. Padois, J.-Y. Fourquet, P. Chiron

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A unified framework for reactive control of wheeled mobile manipulators V. Padois, J.-Y. Fourquet well suited for reactive control approaches which, in the case of mobile manipulation missions a unified modeling framework for wheeled mobile manipulators (WMM). Where most work in the literature often

  16. Kinematic and dynamic model-based control of wheeled mobile manipulators: a unified framework for reactive approaches

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Kinematic and dynamic model-based control of wheeled mobile manipulators: a unified framework aims at providing a unified modeling framework for the reactive control of wheeled mobile manipulators systems is given. This modeling framework is particularly well suited for reactive control approaches

  17. Optimal Power Flow Formulation in Market of Retail Wheeling Taiyou Yong, Student Member, IEEE Robert Lasseter, Fellow, IEEE

    E-Print Network [OSTI]

    power plants, nuclear power plants etc and selling power to consumers. The suppliers have contractsOptimal Power Flow Formulation in Market of Retail Wheeling Taiyou Yong, Student Member, IEEE at Madison, Madison, Wisconsin, USA Abstract: Power system deregulation along with retail wheeling

  18. Developments on the CENS Structural Health Monitoring Front

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    on the CENS Structural Health Monitoring Front D. Skolnik,Introduction: Structural Health Monitoring (SHM) Systems

  19. Developments on the CENS Structural Health Monitoring Front

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    on the CENS Structural Health Monitoring Front D. Skolnik,Introduction: Structural Health Monitoring (SHM) Systems

  20. Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking

    E-Print Network [OSTI]

    A. Allen; Z. Y. Li; F. H. Shu

    2003-11-17T23:59:59.000Z

    We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can be greatly reduced on the way, by an order of magnitude or more, even when the pre-collapse field strength is substantially below the critical value for dominant cloud support. The efficient magnetic braking is due to the pinched geometry of the magnetic field in the pseudodisk, which strengthens the magnetic field and lengthens the level arm for braking. Both effects enhance the magnetic transport of angular momentum from inside to outside. The excess angular momentum is carried away in a low-speed outflow that has, despite claims made by other workers, little in common with observed bipolar molecular outflows. We discuss the implications of our calculations for the formation of true disks that are supported against gravity by rotation.

  1. Probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)

    SciTech Connect (OSTI)

    Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J. [Univ. of Chicago, IL (United States)]|[Stanford Univ., CA (United States). Hoover Institution

    1998-01-01T23:59:59.000Z

    In its most recent report on the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP), the annual failure rate is calculated to be 1.3E({minus}7)(1/yr), rounded off from 1.32E({minus}7). A calculation by the Environmental Evaluation Group (EEG) produces a result that is about 4% higher, namely 1.37E({minus}7)(1/yr). The difference is due to a minor error in the US Department of Energy (DOE) calculations in the Westinghouse 1996 report. WIPP`s hoist safety relies on a braking system consisting of a number of components including two crucial valves. The failure rate of the system needs to be recalculated periodically to accommodate new information on component failure, changes in maintenance and inspection schedules, occasional incidents such as a hoist traveling out-of-control, either up or down, and changes in the design of the brake system. This report examines DOE`s last two reports on the redesigned waste hoist system. In its calculations, the DOE has accepted one EEG recommendation and is using more current information about the component failures rates, the Nonelectronic Parts Reliability Data (NPRD). However, the DOE calculations fail to include the data uncertainties which are described in detail in the NPRD reports. The US Nuclear Regulatory Commission recommended that a system evaluation include mean estimates of component failure rates and take into account the potential uncertainties that exist so that an estimate can be made on the confidence level to be ascribed to the quantitative results. EEG has made this suggestion previously and the DOE has indicated why it does not accept the NRC recommendation. Hence, this EEG report illustrates the importance of including data uncertainty using a simple statistical example.

  2. Hybrid Braking System for Non-Drive Axles | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEND D e e pShade YourHybirdBraking System for

  3. Solar tracker motor having a fixed caliper and a translating caliper each with an electromagnetic brake system

    DOE Patents [OSTI]

    Rau, Scott James

    2013-01-29T23:59:59.000Z

    Concepts and technologies described herein provide for an accurate and cost-effective method for rotating a solar array disk for tracking the movement of the sun. According to various aspects, a motor includes a fixed caliper and a translating caliper positioned adjacent to one another. Electromagnetically controlled brakes on the translating caliper grip the solar array disk while adjacent, but spaced apart, electromagnets on the fixed caliper and the translating caliper are energized to create an attractive force that pulls the translating caliper with the solar array disk toward the fixed caliper. After reaching the fixed caliper, brakes on the fixed caliper are engaged with the disk, brakes on the translating caliper are released from the disk, and the translating caliper is pushed back to the starting location where the process repeats until the desired rotation is completed.

  4. Cooperation of Heterogeneous, Autonomous Robots: A Case Study of Humanoid and Wheeled Robots

    E-Print Network [OSTI]

    Stryk, Oskar von

    . I. INTRO With the growing importance of autonomous mobile robots in industrial and researchCooperation of Heterogeneous, Autonomous Robots: A Case Study of Humanoid and Wheeled Robots Jutta- ation of a strongly heterogeneous robot team, composed of a highly articulated humanoid robot

  5. Continuous Control Primitive Trajectory Generation and Optimal Motion Splines for All-Wheel Steering Mobile

    E-Print Network [OSTI]

    Kelly, Alonzo

    algorithms based on the Ackermann, differential drive, or omnidirectional steering models. Ackerman with all-wheel steering capability differ from these models in that the velocity vector can be aimed in anyContinuous Control Primitive Trajectory Generation and Optimal Motion Splines for All

  6. Modeling and Simulation of a Two wheeled vehicle with suspensions by using Robotic Formalism

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , France (Philippe.chevrel@emn.fr) Abstract: Models, simulators and control strategies are required tools in various situations (e.g. for control application) as simplified model for 3 or 4 wheeled (tilting) cars. In that way, the dynamic model is easy to implement and the system can be used for control applications

  7. MODELING OF SKID-STEERED WHEELED ROBOTIC VEHICLES ON SLOPED TERRAINS

    E-Print Network [OSTI]

    Collins, Emmanuel

    MODELING OF SKID-STEERED WHEELED ROBOTIC VEHICLES ON SLOPED TERRAINS Camilo Ordonez Center radii. This work presents the analysis and experimental verification of a dynamic model for skid-steered for Intelligent Systems, Controls and Robotics (CISCOR) Department of Mechanical Engineering Florida A

  8. Nonparametric Identification of Linearizations and Uncertainty using Gaussian Process Models Application to Robust Wheel Slip Control

    E-Print Network [OSTI]

    Williamson, John

    models, taking into account their uncertainty. The approach is applied to a simulated wheel slip control task illustrating controller development based on a nonparametric model of the unknown friction of the nonlinear models' derivatives. I. INTRODUCTION Robust control is a fairly mature field, in particular

  9. ENERGY-BASED LIMIT CYCLE COMPENSATION FOR DYNAMICALLY BALANCING WHEELED INVERTED PENDULUM MACHINES

    E-Print Network [OSTI]

    Dollar, Aaron M.

    ENERGY-BASED LIMIT CYCLE COMPENSATION FOR DYNAMICALLY BALANCING WHEELED INVERTED PENDULUM MACHINES are not well known. The effects of these non-linearities can be observed in the energy behavior of IP balancing. While in this paper we use an energy-based observer to detect and correct limit cycles while balancing

  10. Vibrotactile Feedback in Steering Wheel Reduces Navigation Errors during GPS-Guided Car Driving

    E-Print Network [OSTI]

    Basdogan, Cagatay

    vibration motors are mounted onto the steering wheel of a driving simulator and driving experiments-based car navigation system to improve the navigation performance of a driver. In [5], vibration motors were auditory noise and distraction exist in the environment, the navigation errors (making a wrong turn

  11. Just Add Wheels: Leveraging Commodity Laptop Hardware for Robotics and AI Education

    E-Print Network [OSTI]

    Sukhatme, Gaurav S.

    . By adding wheels, motors and a motor control board, a modern laptop can be transformed into a capable robot-rich devices. This trend, driven by consumer demand and enabled by improve- ments in solid-state sensor, by using a student's own laptop as part of a capable robot. With the addition of servo motors, a motor

  12. Mixed Control Moment Gyro and Momentum Wheel Attitude Control C. Eugene Skelton II

    E-Print Network [OSTI]

    Hall, Christopher D.

    , or non-moving devices like magnetic torquers. A momentum wheel is a high inertia flywheel mounted which makes them non-ideal for rapid slewing. A control moment gyro has a flywheel mounted on a motor that spins at a constant relative speed. The flywheel and motor are mounted to a gimbal motor that can rotate

  13. Rediscovering the Wheel. Thermochemical Analysis of Energetics of the Aromatic Diazines

    E-Print Network [OSTI]

    Chickos, James S.

    calorimetry and vapor pressure measurements. The gas and condensed phase enthalpies of formation of the parent not the case for diazabenzenes. The previous comprehensive experimental study of both the condensed and gasRediscovering the Wheel. Thermochemical Analysis of Energetics of the Aromatic Diazines Sergey P

  14. Friction forces on phase transition fronts

    E-Print Network [OSTI]

    Ariel Megevand

    2013-03-31T23:59:59.000Z

    In cosmological first-order phase transitions, the microscopic interaction of the phase transition fronts with non-equilibrium plasma particles manifests itself macroscopically as friction forces. In general, it is a nontrivial problem to compute these forces, and only two limits have been studied, namely, that of very slow walls and, more recently, ultra-relativistic walls which run away. In this paper we consider ultra-relativistic velocities and show that stationary solutions still exist when the parameters allow the existence of runaway walls. Hence, we discuss the necessary and sufficient conditions for the fronts to actually run away. We also propose a phenomenological model for the friction, which interpolates between the non-relativistic and ultra-relativistic values. Thus, the friction depends on two friction coefficients which can be calculated for specific models. We then study the velocity of phase transition fronts as a function of the friction parameters, the thermodynamic parameters, and the amount of supercooling.

  15. Propagating and stationary superfluid turbulent fronts

    SciTech Connect (OSTI)

    Castiglione, J.; Murphy, P.J.; Tough, J.T.; Hayot, F. [Ohio State Univ., Columbus, OH (United States)] [and others

    1995-09-01T23:59:59.000Z

    The authors have observed that the critical heat current for the transition to superfluid turbulence in weakly nonuniform circular channels depends strongly on the flow direction. This observation is particularly surprising since no other property of the turbulence appears to have such a dependence. In a nonuniform channel the critical heat current is associated with a stationary front between the laminar and turbulent flow. The authors propose a new model for super-fluid turbulent fronts which explains the asymmetry of the critical heat currents in a simple way. The model is based on the subcritical nature of the transition, and the generic description of such a bifurcation by the Ginzburg-Landau equation. As a bonus, the model also explains a long-standing problem in superfluid physics-the nature of propagating fronts in uniform channels. The results of this analysis of both the uniform and nonuniform channel data also provide new information about the vortex line drift velocity.

  16. Light-front nuclear shell-model

    SciTech Connect (OSTI)

    Johnson, M.B.

    1990-01-01T23:59:59.000Z

    I examine the effects of nuclear structure on high-energy, high-momentum transfer processes, specifically the EMC effect. For pedagogical reasons, a fictitious but simple two-body system consisting of two equal-mass particles interacting in a harmonic oscillator potential has been chosen. For this toy nucleus, I utilize a widely-used link between instant-form and light-front dynamics, formulating nuclear structure and deep-inelastic scattering consistently in the laboratory system. Binding effects are compared within conventional instant-form and light-front dynamical frameworks, with appreciable differences being found in the two cases. 20 refs.

  17. CityCarControl : an electric vehicle drive-by-wire solution for distributed steering, braking and throttle control

    E-Print Network [OSTI]

    Brown, Thomas B., M. Eng. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    In this paper, we propose CityCarControl, a system to manage the steering, braking, and throttle of a new class of intra-city electric vehicles. These vehicles have a focus on extreme light-weight and a small parking ...

  18. Use of an auditory signal in a rear-end collision warning system: effects on braking force and reaction time

    E-Print Network [OSTI]

    Hopkins, Jennifer Susan

    1995-01-01T23:59:59.000Z

    driving game. Superimposed on the game screen was the image of a car which appeared to the driver to be ahead of him/her. The image enlarged in size, appearing to be a car applying its brakes. The participant was instructed to react as he would in a real...

  19. Uncertainty-Enabled Design of a Rocket Sled Track Switch Drs. Jordan E. Massad and Matthew R. Brake

    E-Print Network [OSTI]

    Uncertainty-Enabled Design of a Rocket Sled Track Switch Drs. Jordan E. Massad and Matthew R. Brake Sandia National Laboratories, New Mexico Rocket sled tracks provide a dynamically rich environment acceleration profile, the switch closes to complete a circuit for instrument activation. Preliminary tests

  20. Hybrid: Braking

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center Home PageStationGreenhouse GasCalifornia State0

  1. Hybrid: Braking

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center Home PageStationGreenhouse GasCalifornia State0Button Stopped button

  2. Hybrid: Braking

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center HomeIdle Reduction WeightRebate -

  3. Integration of a testbed for examining the interaction of Mars rover wheels with a Mars soil simulant

    E-Print Network [OSTI]

    Okafor, Chiedozie A. (Chiedozie Arinze)

    2011-01-01T23:59:59.000Z

    Integration and experimental testing was performed on a testbed for examining the interaction of Mars rover wheels with a Mars soil simulant. The testbed included a horizontal carriage that had a encoder to measure the ...

  4. Front-end electronics and trigger systems - status and challenges

    E-Print Network [OSTI]

    Spieler, Helmuth G

    2008-01-01T23:59:59.000Z

    of the 12th Workshop on Electronics For LHC and Future19-24, 2007 Front-end electronics and trigger systems –about a revolution in front-end electronics for large- scale

  5. Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking

    E-Print Network [OSTI]

    Allen, A; Shu, F H

    2003-01-01T23:59:59.000Z

    We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can b...

  6. Developments on the CENS Structural Health Monitoring Front (SEI 2)

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    on the CENS Structural Health Monitoring Front M. Kohler, J.framework for structural health monitoring (SHM). hea lth

  7. Optimal Three-Material Wheel Assemblage of Conducting and Elastic Composites

    E-Print Network [OSTI]

    Andrej Cherkaev

    2011-05-22T23:59:59.000Z

    We describe a new type of three material microstructures which we call wheel assemblages, that correspond to extremal conductivity and extremal bulk modulus for a composite made of two materials and an ideal material. The exact lower bounds for effective conductivity and matching laminates was found in (Cherkaev, 2009) and for anisotropic composites, in (Cherkaev, Zhang, 2011). Here, we show different optimal structures that generalize the classical Hashin-Shtrikman coated spheres (circles). They consist of circular inclusions which contain a solid central circle (hub) and radial spikes in a surrounding annulus, and (for larger volume fractions of the best material) an annulus filled with it. The same wheel assemblages are optimal for the pair of dual problems of minimal conductivity (resistivity) of a composite made from two materials and an ideal conductor (insulator), in the problem of maximal effective bulk modulus of elastic composites made from two linear elastic material and void, and the dual minimum problem.

  8. Pulse width modulated push-pull driven parallel resonant converter with active free-wheel

    DOE Patents [OSTI]

    Reass, William A.; Schrank, Louis

    2004-06-22T23:59:59.000Z

    An apparatus and method for high frequency alternating power generation to control kilowatts of supplied power in microseconds. The present invention includes a means for energy storage, push-pull switching means, control electronics, transformer means, resonant circuitry and means for excess energy recovery, all in electrical communication. A push-pull circuit works synchronously with a force commutated free-wheel transistor to provide current pulses to a transformer. A change in the conduction angle of the push-pull circuit changes the amount of energy coupled into the transformer's secondary oscillating circuit, thereby altering the induced secondary resonating voltage. At the end of each pulse, the force commutated free-wheel transistor causes residual excess energy in the primary circuit to be transmitted back to the storage capacitor for later use.

  9. Pentan isomers compound flame front structure

    SciTech Connect (OSTI)

    Mansurov, Z.A.; Mironenko, A.W.; Bodikov, D.U.; Rachmetkaliev, K.N. [Kazakh Al-Farabi State National Univ., Almaty (Kazakhstan)

    1995-08-13T23:59:59.000Z

    The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to the side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.

  10. Interaction Dynamics of Singular Wave Fronts

    E-Print Network [OSTI]

    Holm, Darryl D

    2013-01-01T23:59:59.000Z

    Some of the most impressive singular wave fronts seen in Nature are the transbasin oceanic internal waves, which may be observed from the Space Shuttle as they propagate and interact with each other, for example, in the South China Sea. The characteristic feature of these strongly nonlinear wavefronts is that they reconnect when two of them collide transversely. We derive the EPDiff equation, and use it to model this phenomenon as elastic collisions between singular wave fronts (solitons) whose momentum is distributed along curves moving in the plane. Numerical methods for EPDiff based on compatible differencing algorithms (CDAs) are used for simulating these collisions among curves. The numerical results show the same nonlinear behavior of wavefront reconnections as that observed for internal waves in the South China Sea. We generalize the singular solutions of EPDiff for other applications, in computational anatomy and in imaging science, where the singular wavefronts are evolving image outlines, whose mome...

  11. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2014-11-04T23:59:59.000Z

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  12. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John (Menlo Park, CA)

    2012-07-17T23:59:59.000Z

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  13. Light-front chiral effective field theory

    SciTech Connect (OSTI)

    Mathiot, J.-F. [Laboratoire de Physique Corpusculaire (France)] [Laboratoire de Physique Corpusculaire (France); Tsirova, N. A., E-mail: ntsirova@ssu.samara.ru [Samara State University (Russian Federation)

    2013-11-15T23:59:59.000Z

    We propose a general framework to calculate the nonperturbative structure of relativistic bound state systems. The state vector of the bound state is calculated in the covariant formulation of light-front dynamics. In this scheme, the state vector is defined on the light front of general position {omega} {center_dot} x = 0, where {omega} is an arbitrary light-like four-vector. This enables a strict control of any violation of rotational invariance. The state vector is then decomposed in Fock components. Our formalism is applied to the description of the nucleon properties at low energy, in chiral perturbation theory. We also show that the use of a recently proposed regularization scheme, the so-called Taylor-Lagrange regularization scheme, is very adequate in order to treat divergences in this nonperturbative framework.

  14. Colloid Formation at Waste Plume Fronts

    SciTech Connect (OSTI)

    Wan, Jiamin; Tokunaga, Tetsu K.; Saiz, Eduardo; Larsen, Joern T.; Zheng, Zuoping; Couture, Rex A.

    2004-05-22T23:59:59.000Z

    Highly saline and caustic tank waste solutions containing radionuclides and toxic metals have leaked into sediments at U. S. Department of Energy (DOE) facilities such as the Hanford Site (Washington State). Colloid transport is frequently invoked to explain migration of radionuclides and metals in the subsurface. To understand colloid formation during interactions between highly reactive fluids and sediments and its impact on contaminant transport, we simulated tank waste solution (TWS) leakage processes in laboratory columns at ambient and elevated (70 C) temperatures. We found that maximum formation of mobile colloids occurred at the plume fronts (hundreds to thousands times higher than within the plume bodies or during later leaching). Concentrations of suspended solids were as high as 3 mass%, and their particle-sizes ranged from tens of nm to a few {micro}m. Colloid chemical composition and mineralogy depended on temperature. During infiltration of the leaked high Na{sup +} waste solution, rapid and completed Na{sup +} replacement of exchangeable Ca{sup 2+} and Mg{sup 2+} from the sediment caused accumulation of these divalent cations at the moving plume front. Precipitation of supersaturated Ca{sup 2+}/Mg{sup 2+}-bearing minerals caused dramatic pH reduction at the plume front. In turn, the reduced pH caused precipitation of other minerals. This understanding can help predict the behavior of contaminant trace elements carried by the tank waste solutions, and could not have been obtained through conventional batch studies.

  15. Design Principles of a flywheel Regenerative Braking System (f-RBS) for Formula SAE type racecar and system testing on a Virtual Test Rig modeled on MSC ADAMS

    E-Print Network [OSTI]

    Pochiraju, Anirudh

    2012-08-31T23:59:59.000Z

    This thesis presents a flywheel based mechanical regenerative braking system (RBS) concept for a Formula SAE type race car application, to improve the performance and/or efficiency of the racecar. A mechanical system is chosen to eliminate losses...

  16. A Braking Index for the Young, High-Magnetic-Field, Rotation-Powered Pulsar in Kes 75

    E-Print Network [OSTI]

    Margaret A. Livingstone; Victoria M. Kaspi; E. V. Gotthelf; Lucien Kuiper

    2006-04-21T23:59:59.000Z

    We present the first phase-coherent measurement of a braking index for the young, energetic rotation-powered pulsar PSR J1846-0258. This 324 ms pulsar is located at the center of the supernova remnant Kes 75 and has a characteristic age of tau_c = 723 years, a spin-down energy of 8.3x10^{36}erg/s, and inferred magnetic field of 4.9x10^{13} G. Two independent phase-coherent timing solutions are derived which together span 5.5 yr of data obtained with the Rossi X-ray Timing Explorer. In addition, a partially phase-coherent timing analysis confirms the fully phase-coherent result. The measured value of the braking index, n=2.65+/-0.01, is significantly less than 3, the value expected from magnetic dipole radiation, implying another physical process must contribute to the pulsar's rotational evolution. Assuming the braking index has been constant since birth, we place an upper limit on the spin-down age of J1846-0258 of 884 yr, the smallest age estimate of any rotation-powered pulsar.

  17. Nonperturbative calculations in light-front QED

    SciTech Connect (OSTI)

    Chabysheva, Sophia S. [Department of Physics, University of Minnesota-Duluth, Duluth, Minnesota 55812 (United States)

    2010-12-22T23:59:59.000Z

    The methods of light-front quantization and Pauli-Villars regularization are applied to a nonperturbative calculation of the dressed-electron state in quantum electrodynamics. This is intended as a test of the methods in a gauge theory, as a precursor to possible methods for the nonperturbative solution of quantum chromodynamics. The electron state is truncated to include at most two photons and no positrons in the Fock basis, and the wave functions of the dressed state are used to compute the electrons's anomalous magnetic moment. A choice of regularization that preserves the chiral symmetry of the massless limit is critical for the success of the calculation.

  18. Front Range Energy LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJumpGermanFife EnergyFreight Best PracticeFrey| Open EnergyFront

  19. Improved wastewater treatment at Wheeling-Pittsburgh Steel Corporations`s Steubenville East Coke Plant

    SciTech Connect (OSTI)

    Goshe, A.J.; Nodianos, M.J. [Wheeling-Pittsburgh Steel Corp., Follansbee, WV (United States)

    1995-12-01T23:59:59.000Z

    Wheeling-Pittsburgh Steel Corporation recently improved its wastewater treatment at it`s by-products coke plant. This has led to greatly improved effluent quality. Excess ammonia liquor, along with wastewater from the light oil recovery plant, desulfurization facility, and coal pile runoff, must be treated prior to being discharged into the Ohio River. This is accomplished using a biological wastewater treatment plant to remove 99.99% of the organic contaminants and ammonia. Biologically treated, clarified wastewater is now polished in the newly constructed tertiary treatment plant.

  20. Sample survey of traditional water wheels and small water turbines in nepal: a preliminary report

    SciTech Connect (OSTI)

    Joshi, C.B.

    1981-01-01T23:59:59.000Z

    The main purposes of this survey were to study the technical, economical, and social aspects of water wheels and turbines; to assess the possibility of developing these modern and traditional technologies together or improving them separately; to assess the awareness of the local people of the need for improvement on their existing technologies; and to find out the possible role of RECAST for mutual cooperation. This survey is intended to provide planners financiers, researchers, and manufacturers with further information regarding better use of small hydro resources and locally available skills for development.

  1. Identifying Lagrangian fronts with favourable fishery conditions

    E-Print Network [OSTI]

    S. V. Prants; M. V. Budyansky; M. Yu. Uleysky

    2013-06-20T23:59:59.000Z

    Lagrangian fronts (LF) in the ocean delineate boundaries between surface waters with different Lagrangian properties. They can be accurately detected in a given velocity field by computing synoptic maps of the drift of synthetic tracers and other Lagrangian indicators. Using Russian ship's catch and location data for a number of commercial fishery seasons in the region of the northwest Pacific with one of the richest fishery in the world, it is shown statistically that the saury fishing grounds with maximal catches are not randomly distributed over the region but located mainly along those LFs where productive cold waters of the Oyashio Current, warmer waters of the southern branch of the Soya Current, and waters of warm-core Kuroshio rings converge. Computation of those fronts with the altimetric geostrophic velocity fields both in the years with the First and Second Oyashio Intrusions shows that in spite of different oceanographic conditions the LF locations may serve good indicators of potential fishing grounds. Possible reasons for saury aggregation near LFs are discussed. We propose a mechanism of effective export of nutrient rich waters based on stretching of material lines in the vicinity of hyperbolic objects in the ocean. The developed method, based on identifying LFs in any velocity fields, is quite general and may be applied to forecast potential fishing grounds for the other pelagic fishes in different seas and the oceans.

  2. apennine front kreep: Topics by E-print Network

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

    Department of Chemical Engineering References and links 1. J. Warnatz, U. Maas, and R.W. Dibble, Combustion - physical and chemical fundamentals, "Characterization of flame front...

  3. One-way, real time wave front converters

    SciTech Connect (OSTI)

    Kwong, S.; Yariv, A.

    1986-03-03T23:59:59.000Z

    Optical one-way, real time wave front cleanup by means of photorefractively pumped oscillators is reported. A factor of 4000 increase in beam brightness has been achieved.

  4. Front instabilities in evaporatively dewetting nanofluids and U. Thiele

    E-Print Network [OSTI]

    Front instabilities in evaporatively dewetting nanofluids I. Vancea and U. Thiele Department of nanoparticles ­ often called nanofluids ­ have recently been used to produce structured nanoparticle layers

  5. Front lighted optical tooling method and apparatus

    DOE Patents [OSTI]

    Stone, W.J.

    1983-06-30T23:59:59.000Z

    An optical tooling method and apparatus uses a front lighted shadowgraphic technique to enhance visual contrast of reflected light. The apparatus includes an optical assembly including a fiducial mark, such as cross hairs, reflecting polarized light with a first polarization, a polarizing element backing the fiducial mark and a reflective surface backing the polarizing element for reflecting polarized light bypassing the fiducial mark and traveling through the polarizing element. The light reflected by the reflecting surface is directed through a second pass of the polarizing element toward the frontal direction with a polarization differing from the polarization of the light reflected by the fiducial mark. When used as a tooling target, the optical assembly may be mounted directly to a reference surface or may be secured in a mounting, such as a magnetic mounting. The optical assembly may also be mounted in a plane defining structure and used as a spherometer in conjunction with an optical depth measuring instrument.

  6. Flame front configuration of turbulent premixed flames

    SciTech Connect (OSTI)

    Furukawa, Junichi [Tokyo Metropolitan Technical Coll. (Japan). Dept. of Mechanical Engineering] [Tokyo Metropolitan Technical Coll. (Japan). Dept. of Mechanical Engineering; Maruta, Kaoru [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science] [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science; Hirano, Toshisuke [Univ. of Tokyo (Japan). Dept. of Chemical System Engineering] [Univ. of Tokyo (Japan). Dept. of Chemical System Engineering

    1998-02-01T23:59:59.000Z

    The present study is performed to explore dependence of the wrinkle scale of propane-air turbulent premixed flames on the characteristics of turbulence in the nonreacting flow, burner size, and mixture ratio. The wrinkle scales are examined and expressed in the frequency distribution of the radii of flame front curvatures. The average wrinkle scale depends not only on the characteristics of turbulence in the nonreacting flow but also on burner diameter and mixture ratio. The average wrinkle scale of a lean propane-air flame is larger than those of the near stoichiometric and rich flames. The smallest wrinkle scale of turbulent premixed flame is in the range of 0.75--1.0 mm, which is much larger than the Kolmogorov scale of turbulence in the nonreacting flow.

  7. Front instabilities in evaporatively dewetting nanofluids

    E-Print Network [OSTI]

    Vancea, I; Pauliac-Vaujour, E; Stannard, A; Martín, C P; Blunt, M O; Moriarty, P J

    2008-01-01T23:59:59.000Z

    Various experimental settings that involve drying solutions or suspensions of nanoparticles -- often called nanofluids -- have recently been used to produce structured nanoparticle layers. In addition to the formation of polygonal networks and spinodal-like patterns, the occurrence of branched structures has been reported. After reviewing the experimental results we use a modified version of the Monte Carlo model first introduced by Rabani et al. [Nature 426, 271 (2003)] to study structure formation in evaporating films of nanoparticle solutions for the case that all structuring is driven by the interplay of evaporating solvent and diffusing nanoparticles. After introducing the model and its general behavior we focus on receding dewetting fronts which are initially straight but develop a transverse fingering instability. We analyze the dependence of the characteristics of the resulting branching patterns on the driving chemical potential, the mobility and concentration of the nanoparticles, and the interactio...

  8. Front instabilities in evaporatively dewetting nanofluids

    E-Print Network [OSTI]

    I. Vancea; U. Thiele; E. Pauliac-Vaujour; A. Stannard; C. P. Martin; M. O. Blunt; P. J. Moriarty

    2008-06-25T23:59:59.000Z

    Various experimental settings that involve drying solutions or suspensions of nanoparticles -- often called nanofluids -- have recently been used to produce structured nanoparticle layers. In addition to the formation of polygonal networks and spinodal-like patterns, the occurrence of branched structures has been reported. After reviewing the experimental results we use a modified version of the Monte Carlo model first introduced by Rabani et al. [Nature 426, 271 (2003)] to study structure formation in evaporating films of nanoparticle solutions for the case that all structuring is driven by the interplay of evaporating solvent and diffusing nanoparticles. After introducing the model and its general behavior we focus on receding dewetting fronts which are initially straight but develop a transverse fingering instability. We analyze the dependence of the characteristics of the resulting branching patterns on the driving chemical potential, the mobility and concentration of the nanoparticles, and the interaction strength between liquid and nanoparticles. This allows us to understand the underlying instability mechanism.

  9. Front contact solar cell with formed electrically conducting layers on the front side and backside

    DOE Patents [OSTI]

    Cousins, Peter John

    2012-06-26T23:59:59.000Z

    A bipolar solar cell includes a backside junction formed by a silicon substrate and a first doped layer of a first dopant type on the backside of the solar cell. A second doped layer of a second dopant type makes an electrical connection to the substrate from the front side of the solar cell. A first metal contact of a first electrical polarity electrically connects to the first doped layer on the backside of the solar cell, and a second metal contact of a second electrical polarity electrically connects to the second doped layer on the front side of the solar cell. An external electrical circuit may be electrically connected to the first and second metal contacts to be powered by the solar cell.

  10. FLUCTUATIONS OF THE FRONT IN A STOCHASTIC COMBUSTION MODEL

    E-Print Network [OSTI]

    Quastel, Jeremy

    FLUCTUATIONS OF THE FRONT IN A STOCHASTIC COMBUSTION MODEL #1; (FLUCTUATIONS DU FRONT DANS UN MODÈLE DE COMBUSTION) FRANCIS COMETS 1 , JEREMY QUASTEL 2 AND ALEJANDRO F. RAMÍREZ 3 Abstract. We consider an interacting particle system on the one dimensional lattice Z modeling combustion. The process

  11. Combustion fronts in porous media with two layers Steve Schecter

    E-Print Network [OSTI]

    Schecter, Stephen

    Combustion fronts in porous media with two layers layer 1 layer 2 Steve Schecter North Carolina Subject: Propagation of a combustion front through a porous medium with two parallel layers having different properties. · Each layer admits a traveling combustion wave. · The layers are coupled by heat

  12. Investigation of the Brazil Current front variability from altimeter data

    E-Print Network [OSTI]

    Investigation of the Brazil Current front variability from altimeter data Gustavo J. Goni Atlantic, Brazil Abstract. The southwestern Atlantic Ocean is characterized by the confluence of the Brazil in conjunction with a two-layer dynamical ocean scheme to monitor the Brazil Current front and to investigate its

  13. Light-Front Holography: A First Approximation to QCD

    SciTech Connect (OSTI)

    de Teramond, Guy F.; Brodsky, Stanley J.

    2008-10-03T23:59:59.000Z

    Starting from the Hamiltonian equation of motion in QCD, we identify an invariant light-front coordinate {zeta} which allows the separation of the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. This light-front wave equation is equivalent to the equations of motion which describe the propagation of spin-J modes on anti-de Sitter (AdS) space. This allows us to establish formally a gauge/gravity correspondence between an effective gravity theory defined on AdS5 and light front QCD.

  14. Criticality and Big Brake singularities in the tachyonic evolutions of closed Friedmann universes with cold dark matter

    E-Print Network [OSTI]

    Horváth, Zsolt; Kamenshchik, Alexander Yu; Gergely, László Á

    2015-01-01T23:59:59.000Z

    The evolution of a closed Friedmann universe filled by a tachyon scalar field with a trigonometric potential and cold dark matter (CDM) is investigated. A subset of the evolutions consistent to 1$\\sigma $ confidence level with the Union 2.1 supernova data set is identified. The evolutions of the tachyon field are classified. Some of them evolve into a de Sitter attractor, while others proceed through a pseudo-tachyonic regime into a sudden future singularity. Critical evolutions leading to Big Brake singularities in the presence of CDM are found and a new type of cosmological evolution characterized by singularity avoidance in the pseudo-tachyon regime is presented.

  15. A closed-loop quasi-optimal dynamic braking resistor and shunt reactor control strategy for transient stability

    SciTech Connect (OSTI)

    Rahim, A.H.M.A.; Alamgir, D.A.H.

    1988-08-01T23:59:59.000Z

    A control strategy for dynamic braking resistor and shunt reactor is proposed for stabilization of power systems when subject to large disturbances. The time optimal control is derived as a function of synchronous machine power, its rotor angular position and speed deviation. The response for a single machine system with the proposed control has been compared with that from the time optimal solution obtained through the steepest descent method. The strategy has also been tested on two multimachine systems. Results indicate that the proposed strategy provides a simple and effective method of stabilization under transient emergency conditions.

  16. Washboard Road: The Dynamics of Granular Ripples Formed by Rolling Wheels Nicolas Taberlet,1,2,* Stephen W. Morris,3

    E-Print Network [OSTI]

    McElwaine, Jim

    experiments on rippled granular surfaces formed under rolling wheels. Ripples appear above a critical speed surface under tangential stress is reminiscent of other sorts of wind- and water-driven ripples [2 rolled freely on the sand bed as the table rotated at a constant speed. No torque was applied

  17. A Dual Model-Free Control of Underactuated Mechanical Systems, Application to The Inertia Wheel Inverted Pendulum

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    regulation. The main contribution of this paper is to design a new control scheme based on model-free controlA Dual Model-Free Control of Underactuated Mechanical Systems, Application to The Inertia Wheel method allowing recent model-free control technique to deal with underactuated mechanical systems

  18. Abstract--This video submission presents the experimental validation and testing of a leg-wheel hybrid mobile robot

    E-Print Network [OSTI]

    Lin, Pei-Chun

    is installed inside the spoke and its power and control signal are passed through a connector pair, which have separate mechanisms of wheels and legs, this robot is implemented with a transformation mechanism inventions specialized in rolling on the flat ground, whose excellent performance of power efficiency

  19. Biomechanical and psychophysical evaluation of using a two-wheel cart to transport loads over a curb

    E-Print Network [OSTI]

    King, Rebecca Lynn

    1997-01-01T23:59:59.000Z

    The purpose of this study was to evaluate the use of a standard two-wheel cart to transport loads over a curb. This was done through biomechanical (static and dynamic) and psychophysical evaluations of industrial males. The biomechanical study (n=4...

  20. Front lighted optical tooling method and apparatus

    DOE Patents [OSTI]

    Stone, William J. (Kansas City, MO)

    1985-06-18T23:59:59.000Z

    An optical tooling method and apparatus uses a front lighted shadowgraphic technique to enhance visual contrast of reflected light. The apparatus includes an optical assembly including a fiducial mark, such as cross hairs, reflecting polarized light with a first polarization, a polarizing element backing the fiducial mark and a reflective surface backing the polarizing element for reflecting polarized light bypassing the fiducial mark and traveling through the polarizing element. The light reflected by the reflecting surface is directed through a second pass of the polarizing element toward the frontal direction with a polarization differing from the polarization of the light reflected by the fiducial mark. When used as a tooling target, the optical assembly may be mounted directly to a reference surface or may be secured in a mounting, such as a magnetic mounting. The optical assembly may also be mounted in a plane defining structure and used as a spherometer in conjunction with an optical depth measuring instrument. A method of measuring a radius of curvature of an unknown surface includes positioning the spherometer on a surface between the surface and a depth measuring optical instrument. As the spherometer is frontally illuminated, the distance from the depth measuring instrument to the fiducial mark and the underlying surface are alternately measured and the difference in these measurements is used as the sagittal height to calculate a radius of curvature.

  1. Spin-1 Particles with Light-Front Approach

    E-Print Network [OSTI]

    J. P. B. C. de Melo; Anacé N. da Silva; Clayton S. Mello; T. Frederico

    2015-04-27T23:59:59.000Z

    For the vector sector, i.e, mesons with spin-1, the electromagnetic form factors and anothers observables are calculated with the light-front approach. However, the light-front quantum field theory have some problems, for example, the rotational symmetry breaking. We solve that problem added the zero modes contribuition to the matrix elements of the electromagnetic current, besides the valence contribuition. We found that among the four independent matrix elements of the plus component in the light-front helicity basis only the $0\\to 0$ one carries zero mode contributions.

  2. Electron g-2 in Light-front Quantization

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

    Zhao, Xingbo; Honkanen, Heli; Maris, Pieter; Vary, James P.; Brodsky, Stanley J.

    2014-10-01T23:59:59.000Z

    Basis Light-front Quantization has been proposed as a nonperturbative framework for solving quantum field theory. We apply this approach to Quantum Electrodynamics and explicitly solve for the light-front wave function of a physical electron. Based on the resulting light-front wave function, we evaluate the electron anomalous magnetic moment. Nonperturbative mass renormalization is performed. Upon extrapolation to the infinite basis limit our numerical results agree with the Schwinger result obtained in perturbation theory to an accuracy of 0.06%.

  3. Electron g-2 in Light-Front Quantization

    E-Print Network [OSTI]

    Xingbo Zhao; Heli Honkanen; Pieter Maris; James P. Vary; Stanley J. Brodsky

    2014-08-24T23:59:59.000Z

    Basis Light-front Quantization has been proposed as a nonperturbative framework for solving quantum field theory. We apply this approach to Quantum Electrodynamics and explicitly solve for the light-front wave function of a physical electron. Based on the resulting light-front wave function, we evaluate the electron anomalous magnetic moment. Nonperturbative mass renormalization is performed. Upon extrapolation to the infinite basis limit our numerical results agree with the Schwinger result obtained in perturbation theory to an accuracy of 0.06%.

  4. Light front approach to correlations in hot quark matter

    E-Print Network [OSTI]

    S. Strauss; M. Beyer; S. Mattiello

    2006-01-30T23:59:59.000Z

    We investigate two-quark correlations in hot and dense quark matter. To this end we use the light front field theory extended to finite temperature $T$ and chemical potential $\\mu$. Therefore it is necessary to develop quantum statistics formulated on the light front plane. As a test case for light front quantization at finite $T$ and $\\mu$ we consider the NJL model. The solution of the in-medium gap equation leads to a constituent quark mass which depends on $T$ and $\\mu$. Two-quark systems are considered in the pionic and diquark channel. We compute the masses of the two-body system using a $T$-matrix approach.

  5. Muon capture for the front end of a muon collider

    SciTech Connect (OSTI)

    Neuffer, D.; /Fermilab; Yoshikawa, C.; /MUONS Inc., Batavia

    2011-03-01T23:59:59.000Z

    We discuss the design of the muon capture front end for a {mu}{sup +}-{mu}{sup -} Collider. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. The muons are then cooled and accelerated to high energy into a storage ring for high-energy high luminosity collisions. Our initial design is based on the somewhat similar front end of the International Design Study (IDS) neutrino factory.

  6. Biofuels development in Maine: Using trees to oil the wheels of sustainability -Maine news, sports, obituaries, weather -Bangor Daily News http://bangordailynews.com/2013/03/12/opinion/biofuels-development-in-maine-using-trees-to-oil-the-wheels-of-sustain

    E-Print Network [OSTI]

    Thomas, Andrew

    Biofuels development in Maine: Using trees to oil the wheels of sustainability - Maine news, sports, obituaries, weather - Bangor Daily News http://bangordailynews.com/2013/03/12/opinion/biofuels-development-in-maine-using-trees-to-oil-the-wheels-of-sustainability/print/[3/13/2013 1:54:43 PM] Biofuels development

  7. Advanced integrated safeguards using front-end-triggering devices

    SciTech Connect (OSTI)

    Howell, J.A.; Whitty, W.J.

    1995-12-01T23:59:59.000Z

    This report addresses potential uses of front-end-triggering devices for enhanced safeguards. Such systems incorporate video surveillance as well as radiation and other sensors. Also covered in the report are integration issues and analysis techniques.

  8. Speed-up of combustion fronts in shear flows

    E-Print Network [OSTI]

    Hamel, Francois

    2011-01-01T23:59:59.000Z

    This paper is concerned with the analysis of speed-up of reaction-diffusion-advection traveling fronts in infinite cylinders with periodic boundary conditions. The advection is a shear flow with a large amplitude and the reaction is nonnegative, with either positive or zero ignition temperature. The unique or minimal speeds of the traveling fronts are proved to be asymptotically linear in the flow amplitude as the latter goes to infinity, solving an open problem from \\cite{b}. The asymptotic growth rate is characterized explicitly as the unique or minimal speed of traveling fronts for a limiting degenerate problem, and the convergence of the regular traveling fronts to the degenerate ones is proved for positive ignition temperatures under an additional H{\\"{o}}rmander-type condition on the flow.

  9. Helpful Numbers Cougar Place Front Desk (713) 743-

    E-Print Network [OSTI]

    Azevedo, Ricardo

    Helpful Numbers Cougar Place Front Desk (713) 743- 6994 Housing Office (713) 743-6000 RLC Office) 743-7529 Facebook.com/UHCougarPlace Twitter & IG : UHCougarPlace #12;What's Going On? Parents

  10. Home Front as Warfront: African American World War I Drama

    E-Print Network [OSTI]

    Egging, Anna Katherine

    2010-08-31T23:59:59.000Z

    This dissertation recovers little-known African American World War I plays that blur the boundary between the home front and warfront. I argue that with this focus, the plays wage their own war for African American citizenship ...

  11. RF CMOS UWB transmitter and receiver front-end design

    E-Print Network [OSTI]

    Miao, Meng

    2009-05-15T23:59:59.000Z

    The low-cost low-power complementary metal-oxide semiconductor (CMOS) ultra wideband (UWB) transmitter and receiver front-ends based on impulse technology were developed. The CMOS UWB pulse generator with frequency-band tuning capability...

  12. Stability of Propagating Fronts in Damped Hyperbolic Equations

    E-Print Network [OSTI]

    Stability of Propagating Fronts in Damped Hyperbolic Equations Th. Gallay, G. Raugel Analyse Num'erique et EDP CNRS et Universit'e de Paris­Sud F­91405 Orsay Cedex, France Thierry.Gallay

  13. Carbon Emissions from Smouldering Peat in Shallow and Strong Fronts 

    E-Print Network [OSTI]

    Rein, Guillermo; Cohen, Simon; Simeoni, Albert

    2009-01-01T23:59:59.000Z

    A series of experiments of shallow and strong smouldering fronts in boreal peat have been conducted under laboratory conditions to study the CO and CO2 emissions. Peat samples of 100 mm by 100 mm in cross section and 50 ...

  14. Front End Loading (FEL) and Process Engineering Workflow

    E-Print Network [OSTI]

    Spangler, Ryan

    2005-05-20T23:59:59.000Z

    Project development for the oil refining industry is typically performed through a process called Front End Loading (FEL). In recent years, the Process and Industrial Division of Burns and McDonnell has performed several ...

  15. Global optimization of silicon photovoltaic cell front coatings

    E-Print Network [OSTI]

    Ghebrebrhan, Michael

    The front-coating (FC) of a solar cell controls its efficiency, determining admission of light into the absorbing material and potentially trapping light to enhance thin absorbers. Single-layer FC designs are well known, ...

  16. Colorado Front Range Fuel Photo Series Michael A. Battaglia

    E-Print Network [OSTI]

    Fried, Jeremy S.

    Colorado Front Range Fuel Photo Series Michael A. Battaglia Jonathan M. Dodson Wayne D. Shepperd of Agriculture Forest Service Rocky Mountain Research Station June 2005 #12;Battaglia, Michael A.; Dodson

  17. Renormalized Light Front Hamiltonian in the Pauli-Villars Regularization

    E-Print Network [OSTI]

    M. Yu. Malyshev; S. A. Paston; E. V. Prokhvatilov; R. A. Zubov

    2014-09-03T23:59:59.000Z

    We address the problem of nonperturbative calculations on the light front in quantum field theory regularized by Pauli-Villars method. As a preliminary step we construct light front Hamiltonians in (2+1)-dimensional $\\lambda\\phi^4$ model, for the cases without and with spontaneous symmetry breaking. The renormalization of these Hamiltonians in Pauli-Villars regularization is carried out via comparison of all-order perturbation theory, generated by these Hamiltonians, and the corresponding covariant perturbation theory in Lorentz coordinates.

  18. Radio frequency circuits for wireless receiver front-ends

    E-Print Network [OSTI]

    Xin, Chunyu

    2005-11-01T23:59:59.000Z

    . . . . . . . . 69 2. Implementation of the Down-Conversion Mixer . . . . 69 3. Layout Considerations and Simulation Results . . . . 74 4. Experimental Results of the Mixer Within the Receiver 77 IV BLUETOOTH/WI-FI DUAL-STANDARD RECEIVER RF FRONT...-END : : : : : : : : : : : : : : : : : : : : : : : : : : : : 80 A. Direct Conversion Bluetooth/Wi-Fi Dual-Standard Receiver 81 B. RF Front-End Design Considerations . . . . . . . . . . . . 83 C. Circuits Implementations . . . . . . . . . . . . . . . . . . . 86 1. LNA Implementation...

  19. Design and Implementation of a Teleautonomous Hummer Darrin C. Bentivegna, Khaled S. Ali, Ronald C. Arkin and Tucker Balch

    E-Print Network [OSTI]

    for steering, brake, and throttle have been implemented on a commercially available Hummer. Control is provided to feedback sensors for the steering wheel, brake, and forward speed; and a Unix workstation for high control the steering wheel, brake pedal and throttle. A control computer performs low­level computation

  20. Hydraulic Drivetrain and Regenerative Braking Team 13: Andrew Brown, Karan Desai, Andrew McGrath, Hurst Nuckols, Grant Wilson Adviser: Dr. Andrew Jackson

    E-Print Network [OSTI]

    Carpick, Robert W.

    Hydraulic Drivetrain and Regenerative Braking Team 13: Andrew Brown, Karan Desai, Andrew Mc Pressure Reservior Filter Variable Vane Pump Motor/Pump Hydraulic Accumulators Solenoid Valve Relief Valve Suction Line Since their development in 2006, hydraulic drivetrain systems have gained considerable

  1. The role of the cant and lateral position of the steering wheel in the orientation of drivers to the location of the automotive pedals

    E-Print Network [OSTI]

    Sherrod, M. G

    1989-01-01T23:59:59.000Z

    examined the effects of three steering wheel cants and three steering wheel lateral positions on drivers' preferred automotive foot pedal locations and separation distances. The dependent variables were the preferred vertical and horizontal positions... in orienting the driver to the locations of the pedals and should be part of any design recommendations detailing the relationship between the driver and the foot pedals. ACKNOWLEDGEMENTS I would like to thank the chairman of my Advisory Committee, Dr...

  2. An analysis of the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)

    SciTech Connect (OSTI)

    Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J.

    1995-11-01T23:59:59.000Z

    The Environmental Evaluation Group (EEG) previously analyzed the probability of a catastrophic accident in the waste hoist of the Waste Isolation Pilot Plant (WIPP) and published the results in Greenfield (1990; EEG-44) and Greenfield and Sargent (1993; EEG-53). The most significant safety element in the waste hoist is the hydraulic brake system, whose possible failure was identified in these studies as the most important contributor in accident scenarios. Westinghouse Electric Corporation, Waste Isolation Division has calculated the probability of an accident involving the brake system based on studies utilizing extensive fault tree analyses. This analysis conducted for the U.S. Department of Energy (DOE) used point estimates to describe the probability of failure and includes failure rates for the various components comprising the brake system. An additional controlling factor in the DOE calculations is the mode of operation of the brake system. This factor enters for the following reason. The basic failure rate per annum of any individual element is called the Event Probability (EP), and is expressed as the probability of failure per annum. The EP in turn is the product of two factors. One is the {open_quotes}reported{close_quotes} failure rate, usually expressed as the probability of failure per hour and the other is the expected number of hours that the element is in use, called the {open_quotes}mission time{close_quotes}. In many instances the {open_quotes}mission time{close_quotes} will be the number of operating hours of the brake system per annum. However since the operation of the waste hoist system includes regular {open_quotes}reoperational check{close_quotes} tests, the {open_quotes}mission time{close_quotes} for standby components is reduced in accordance with the specifics of the operational time table.

  3. ITS Technologies in Military Wheeled Tactical Vehicles: Status Quo and the Future

    SciTech Connect (OSTI)

    Knee, H.E.

    2001-07-02T23:59:59.000Z

    The U.S. Army operates and maintains the largest trucking fleet in the United States. Its fleet consists of over 246,000 trucks, and it is responsible for buying and developing trucks for all branches of the armed forces. The Army's tactical wheeled vehicle fleet is the logistical backbone of the Army, and annually, the fleet logs about 823 million miles. The fleet consists of a number of types of vehicles. They include eight different families of trucks from the High Mobility Multi-Purpose Wheeled Vehicles to M900 series line haul tractors and special bodies. The average age of all the trucks within the Army fleet is 15 years, and very few have more than traditional driving instrumentation on-board. Over the past decade, the Department of Transportation's (DOT's) Intelligent Transportation Systems (ITS) Program has conducted research and deployment activities in a number of areas including in-vehicle systems, communication and telematics technologies. Many current model passenger vehicles have demonstrated the assimilation of these technologies to enhance safety and trip quality. Commercial vehicles are also demonstrating many new electronic devices that are assisting in making them safer and more efficient. Moreover, a plethora of new technologies are about to be introduced to drivers that promise greater safety, enhanced efficiency, congestion avoidance, fuel usage reduction, and enhanced trip quality. The U.S. Army has special needs with regard to fleet management, logistics, sustainability, reliability, survivability, and fuel consumption that goes beyond similar requirements within the private industry. In order to effectively apply emerging ITS technologies to the special needs of the U.S. Army, planning for the conduct of the Army's Vehicle Intelligence Program (AVIP) has now commenced. The AVIP will be focused on the conduct of research that: (1) will apply ITS technologies to the special needs of the Army, and (2) will conduct research for special needs wi th regard to vehicle control, driver assistance, integration of vehicle intelligence and robotic technologies, managing effectively the information flow to drivers, enhanced logistics capabilities and sustainability of the Army's fleet during battlefield conditions. This paper will highlight the special needs of the Army, briefly describe two programs, which are embracing ITS technologies to a limited extent, will outline the AVIP, and will provide some insight into future Army vehicle intelligence efforts.

  4. Methods for enhancing mapping of thermal fronts in oil recovery

    DOE Patents [OSTI]

    Lee, David O. (Albuquerque, NM); Montoya, Paul C. (Albuquerque, NM); Wayland, Jr., James R. (Albuquerque, NM)

    1987-01-01T23:59:59.000Z

    A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the CSAMT technique is disclosed. This method includes the steps of: (a) preparing a CSAMT-determined topological resistivity map of the production field; (b) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the connate water of the production field; (c) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and (d) mathematically comparing the maps from step (a) and step (c) to determine the location of the thermal front. This method is effective with the steam flood, fire flood and water flood techniques.

  5. Acoustic wave front reversal in a three-phase media

    E-Print Network [OSTI]

    N. I. Pushkina

    2015-03-05T23:59:59.000Z

    Acoustic wave front conjugation is studied in a sandy marine sediment that contains air bubbles in its fluid fraction. The considered phase conjugation is a four-wave nonlinear parametric sound interaction process caused by nonlinear bubble oscillations which are known to be dominant in acoustic nonlinear interactions in three-phase marine sediments. Two various mechanisms of phase conjugation are studied. One of them is based on the stimulated Raman-type sound scattering on resonance bubble oscillations. The second one is associated with sound interactions with bubble oscillations which frequencies are far from resonance bubble frequencies. Nonlinear equations to solve the wave-front conjugation problem are derived, expressions for acoustic wave amplitudes with a reversed wave front are obtained and compared for various frequencies of the excited bubble oscillations.

  6. Acoustic wave front conjugation in a three-phase media

    E-Print Network [OSTI]

    Pushkina, N I

    2015-01-01T23:59:59.000Z

    Acoustic wave front reversal is studied in a sandy marine sediment that contains air bubbles in its fluid fraction. The considered phase conjugation is a four-wave nonlinear parametric sound interaction process caused by nonlinear bubble oscillations which are known to be dominant in acoustic nonlinear interactions in three-phase marine sediments. Two various mechanisms of phase conjugation are studied. One of them is based on the stimulated Raman-type sound scattering on resonance bubble oscillations. The second one is associated with sound interactions with bubble oscillations which frequencies are far from resonance bubble frequencies. Nonlinear equations to solve the wave-front conjugation problem are derived, expressions for acoustic wave amplitudes with a reversed wave front are obtained and compared for various frequencies of the excited bubble oscillations.

  7. Methods for enhancing mapping of thermal fronts in oil recovery

    DOE Patents [OSTI]

    Lee, D.O.; Montoya, P.C.; Wayland, J.R. Jr.

    1984-03-30T23:59:59.000Z

    A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the controlled source audio frequency magnetotelluric (CSAMT) technique is disclosed. This method includes the steps of: (1) preparing a CSAMT-determined topological resistivity map of the production field; (2) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the conate water of the production field; (3) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and (4) mathematically comparing the maps from step (1) and step (3) to determine the location of the thermal front. This method is effective with the steam flood, fire flood and water flood techniques.

  8. Light-front holographic QCD and emerging confinement

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

    Brodsky, Stanley J.; de Téramond, Guy F.; Dosch, Hans Günter; Erlich, Joshua

    2015-07-01T23:59:59.000Z

    In this report we explore the remarkable connections between light-front dynamics, its holographic mapping to gravity in a higher-dimensional anti-de Sitter (AdS) space, and conformal quantum mechanics. This approach provides new insights into the origin of a fundamental mass scale and the physics underlying confinement dynamics in QCD in the limit of massless quarks. The result is a relativistic light-front wave equation for arbitrary spin with an effective confinement potential derived from a conformal action and its embedding in AdS space. This equation allows for the computation of essential features of hadron spectra in terms of a single scale. Themore »light-front holographic methods described here give a precise interpretation of holographic variables and quantities in AdS space in terms of light-front variables and quantum numbers. This leads to a relation between the AdS wave functions and the boost-invariant light-front wave functions describing the internal structure of hadronic bound-states in physical spacetime. The pion is massless in the chiral limit and the excitation spectra of relativistic light-quark meson and baryon bound states lie on linear Regge trajectories with identical slopes in the radial and orbital quantum numbers. In the light-front holographic approach described here currents are expressed as an infinite sum of poles, and form factors as a product of poles. At large q 2 the form factor incorporates the correct power-law fall-off for hard scattering independent of the specific dynamics and is dictated by the twist. At low q 2 the form factor leads to vector dominance. The approach is also extended to include small quark masses. We briefly review in this report other holographic approaches to QCD, in particular top-down and bottom-up models based on chiral symmetry breaking. We also include a discussion of open problems and future applications.« less

  9. Light-Front Holographic QCD and Emerging Confinement

    E-Print Network [OSTI]

    Stanley J. Brodsky; Guy F. de Teramond; Hans Gunter Dosch; Joshua Erlich

    2015-02-13T23:59:59.000Z

    In this report we explore the remarkable connections between light-front dynamics, its holographic mapping to gravity in a higher-dimensional anti-de Sitter (AdS) space, and conformal quantum mechanics. This approach provides new insights into the origin of a fundamental mass scale and the physics underlying confinement dynamics in QCD in the limit of massless quarks. The result is a relativistic light-front wave equation for arbitrary spin with an effective confinement potential derived from a conformal action and its embedding in AdS space. This equation allows for the computation of essential features of hadron spectra in terms of a single scale. The light-front holographic methods described here gives a precise interpretation of holographic variables and quantities in AdS in terms of light-front variables and quantum numbers. This leads to a relation between the AdS wave functions and the boost-invariant light-front wave functions describing the internal structure of hadronic bound states in physical space-time. The pion is massless in the chiral limit and the excitation spectra of relativistic light-quark meson and baryon bound states lie on linear Regge trajectories with identical slopes in the radial and orbital quantum numbers. In the light-front holographic approach described here currents are expressed as an infinite sum of poles, and form factors as a product of poles. At large $q^2$ the form factor incorporates the correct power-law fall-off for hard scattering independent of the specific dynamics and is dictated by the twist. At low $q^2$ the form factor leads to vector dominance. The approach is also extended to include small quark masses. We briefly review in this report other holographic approaches to QCD, in particular top-down and bottom-up models based on chiral symmetry breaking. We also include a discussion of open problems and future applications.

  10. Light-front holographic QCD and emerging confinement

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

    Brodsky, Stanley J. [SLAC National Accelerator Laboratory, Stanford, CA (United States); de Téramond, Guy F. [Universidad de Costa Rica, San José, (Costa Rica); Dosch, Hans Günter [Institut für Theoretische Physik, Heidelberg (Germany); Erlich, Joshua [College of William and Mary, Williamsburg, VA (United States)

    2015-07-01T23:59:59.000Z

    In this report we explore the remarkable connections between light-front dynamics, its holographic mapping to gravity in a higher-dimensional anti-de Sitter (AdS) space, and conformal quantum mechanics. This approach provides new insights into the origin of a fundamental mass scale and the physics underlying confinement dynamics in QCD in the limit of massless quarks. The result is a relativistic light-front wave equation for arbitrary spin with an effective confinement potential derived from a conformal action and its embedding in AdS space. This equation allows for the computation of essential features of hadron spectra in terms of a single scale. The light-front holographic methods described here give a precise interpretation of holographic variables and quantities in AdS space in terms of light-front variables and quantum numbers. This leads to a relation between the AdS wave functions and the boost-invariant light-front wave functions describing the internal structure of hadronic bound-states in physical spacetime. The pion is massless in the chiral limit and the excitation spectra of relativistic light-quark meson and baryon bound states lie on linear Regge trajectories with identical slopes in the radial and orbital quantum numbers. In the light-front holographic approach described here currents are expressed as an infinite sum of poles, and form factors as a product of poles. At large q 2 the form factor incorporates the correct power-law fall-off for hard scattering independent of the specific dynamics and is dictated by the twist. At low q 2 the form factor leads to vector dominance. The approach is also extended to include small quark masses. We briefly review in this report other holographic approaches to QCD, in particular top-down and bottom-up models based on chiral symmetry breaking. We also include a discussion of open problems and future applications.

  11. On the speed of fast and slow rupture fronts along frictional interfaces

    E-Print Network [OSTI]

    Trømborg, Jørgen Kjoshagen; Thøgersen, Kjetil; Scheibert, Julien; Malthe-Sørenssen, Anders

    2015-01-01T23:59:59.000Z

    The transition from stick to slip at a dry frictional interface occurs through the breaking of the junctions between the two contacting surfaces. Typically, interactions between the junctions through the bulk lead to rupture fronts propagating from weak and/or highly stressed regions, whose junctions break first. Experiments find rupture fronts ranging from quasi-static fronts with speeds proportional to external loading rates, via fronts much slower than the Rayleigh wave speed, and fronts that propagate near the Rayleigh wave speed, to fronts that travel faster than the shear wave speed. The mechanisms behind and selection between these fronts are still imperfectly understood. Here we perform simulations in an elastic 2D spring--block model where the frictional interaction between each interfacial block and the substrate arises from a set of junctions modeled explicitly. We find that a proportionality between material slip speed and rupture front speed, previously reported for slow fronts, actually holds ac...

  12. Travel Reimbursement Request Form Submit to: Front Desk

    E-Print Network [OSTI]

    Rose, Michael R.

    Travel Reimbursement Request Form Submit to: Front Desk Department of Pharmaceutial Sciences 147 expenses) If travel time does not include overnight stay (between 7AM - 8PM), the traveler should not claim before 11 AM and arrival after 2 PM; dinner - departure before 5 PM. PM and arrival after 7 PM NOTE

  13. Travel Reimbursement Request Form Submit to: Front Desk

    E-Print Network [OSTI]

    Loudon, Catherine

    Travel Reimbursement Request Form Submit to: Front Desk Department of Pharmaceutical Sciences 147 : Maximum: $71.00 (Itemize meal expenses) If travel time does not include overnight stay (between 7AM - 8PM; lunch - departure before 11 AM and arrival after 2 PM; dinner - departure before 5 PM. PM and arrival

  14. IDENTIFICATION OF MOBILITIES FOR THE BUCKLEYLEVERETT EQUATION BY FRONT TRACKING

    E-Print Network [OSTI]

    IDENTIFICATION OF MOBILITIES FOR THE BUCKLEY­LEVERETT EQUATION BY FRONT TRACKING VIDAR HAUGSE Multi--phase flow in porous media is modelled by Darcy's law. This empirical relation relates is also used to solve the saturation equation in a commercial reservoir simulator [1]. 2. Equations

  15. An Adaptive Front-end Readout System for Radiation Detection

    E-Print Network [OSTI]

    Stanacevic, Milutin

    An Adaptive Front-end Readout System for Radiation Detection Xiao Yun and Milutin Stana to compensate for the variations of the detector and readout circuitry. II. READOUT SYSTEM FOR RADIATION DETECTION Readout circuitry is directly interfaced to the photodiode and produces a voltage signal

  16. Flame front tracking by laser induced fluorescence spectroscopy and advanced

    E-Print Network [OSTI]

    Hamarneh, Ghassan

    surface characteristics in turbulent premixed propane/air combustion," Combustion and Flame 120(4), 407 References and links 1. J. Warnatz, U. Maas, and R.W. Dibble, Combustion - physical and chemical fundamentals, "Characterization of flame front surfaces in turbulent premixed methane/air combustion," Combustion and Flame 101

  17. Front Vehicle Blind Spot Translucentization Based on Augmented Reality

    E-Print Network [OSTI]

    Wang, Yuan-Fang

    Front Vehicle Blind Spot Translucentization Based on Augmented Reality Che-Tsung Lin, Yu-Chen Lin--Recently, WAVE/DSRC has become an attrac- tive technology for vehicular safety applications. Vehicles with WAVE/DSRC devices can communicate with their neighboring vehicles to exchange information to achieve collaborative

  18. Front and backside processed thin film electronic devices

    DOE Patents [OSTI]

    Evans, Paul G. (Madison, WI); Lagally, Max G. (Madison, WI); Ma, Zhenqiang (Middleton, WI); Yuan, Hao-Chih (Lakewood, CO); Wang, Guogong (Madison, WI); Eriksson, Mark A. (Madison, WI)

    2012-01-03T23:59:59.000Z

    This invention provides thin film devices that have been processed on their front- and backside. The devices include an active layer that is sufficiently thin to be mechanically flexible. Examples of the devices include back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

  19. Mechanism of Preferential Adsorption of SO2 into Two Microporous Paddle Wheel Frameworks M(bdc)(ted)(0.5)

    SciTech Connect (OSTI)

    Tan, Kui; Canepa, Pieremanuele; Gong, Qihan; Liu, Jian; Johnson, Daniel H.; Dyevoich, Allison A.; Thallapally, Praveen K.; Thonhauser, Timo; Li, Jing; Chabal, Y. J.

    2013-12-02T23:59:59.000Z

    The adsorption of a corrosive gas, SO¬2, into microporous pillared paddle-wheel frameworks M(bdc)(ted)0.5 [M = Ni, , Zn; bdc = 1,4-benzenedicarboxylate; ted=triethylenediamine] is studied by volumetric adsorption measurements and a combination of in-situ infrared spectroscopy and ab initio density functional theory (DFT) calculations. The uptake of SO2 in M(bdc)(ted)0.5 at room temperature is quite significant, 9.966 mol kg-1(63.8%) at room temperature/1.132 bar, which represents the highest SO2 uptake so far observed. Two different adsorption species are identified by infrared spectroscopy: one is typical physisorbed SO2 species, charac-terized by a modest red shift of S-O stretching bands (36 cm-1 for ?as and 7 cm-1 for ?s); the other characterized by adsorption bands at 1242 and 1105cm-1 and by a much higher (~150?C) temperature to completely remove. Theoretical calculations including van der Waals interactions (based on vdW-DF) indicate that the adsorption geometry of SO2 involves one molecule bonding of its sulfur atom to the oxygen atom of the paddle-wheel building unit and its two oxygen atoms to the C-H groups of the organic linkers by formation of hydrogen bonds. Such a configuration results in a large distortion of benzene rings, which is consistent with the experimentally observed shift of the ring deformation mode. The simulated frequency shift of the SO2 stretching bands by vdW-DF is in excellent agreement with spectroscopically measured value of physisorbed SO2. The IR absorptions at 1242 and 1105 cm-1 also suggest a stronger adsorption configuration, previously observed in SO4-like species involving two oxygen atoms of the paddle wheel building units. The adsorption configurations of SO2 into M(bdc)(ted)0.5 derived by infrared spectroscopy and vdW-DF calculations provide the understanding necessary to develop industrial processes for SO2 removal using microporous paddle-wheel frameworks materials.

  20. A study of certain elastic and plastic strains induced in flexible pavement systems by repetitive wheel loads

    E-Print Network [OSTI]

    Meyer, Kirby Thomas

    1959-01-01T23:59:59.000Z

    Vehicle Magnitude of Hheel Load and Tire Pressure Repetitive Testing The Testing Procedures 50 Effect of Area of Influence of Nheel Load on Data Validity Horisontal extent of pavement depression under load wheel 50 51 Effect of depressed area ou... sites 12, 13, and 14. 25. Illustration of the plate and the placement of the beam probes in a study of extrusion between the tires 26. A comparison of measured deflections on the plate with 28 31 33 39 39 40 43 those on the pavmsent 27. A...

  1. "It's Like Giving Us a Car, Only Without the Wheels": Performance of Latina Students at an Early College High School

    E-Print Network [OSTI]

    Locke, Leslie Ann

    2012-02-14T23:59:59.000Z

    School. (December 2011) Leslie Ann Locke, B.S.; M.L.S, University of Minnesota?Twin Cities Chair of Advisory Committee: Dr. Kathryn McKenzie This dissertation presents the results from an empirical study of the perspectives of Latina students who... ?IT?S LIKE GIVING US A CAR, ONLY WITHOUT THE WHEELS?: PERFORMANCE OF LATINA STUDENTS AT AN EARLY COLLEGE HIGH SCHOOL A Dissertation by LESLIE ANN LOCKE Submitted to the Office of Graduate Studies of Texas A&M University...

  2. Massively Parallel Computation of Sti Propagating Combustion frontsMarc Garbey and Damien Tromeur-Dervout

    E-Print Network [OSTI]

    Garbey, Marc

    In this paper we study the computation of combustion fronts using MIMD archi- tecture. Our applications in gas models of combustion fronts: rst, a classical thermo-di usive model describing the combustion of a gasMassively Parallel Computation of Sti Propagating Combustion frontsMarc Garbey and Damien Tromeur

  3. Physics design of front ends for superconducting ion linacs

    SciTech Connect (OSTI)

    Ostroumov, P.N.; /Argonne; Carneiro, J.P.; /Fermilab

    2009-01-01T23:59:59.000Z

    Superconducting (SC) technology is the only option for CW linacs and is also an attractive option for pulsed linacs. SC cavities are routinely used for proton and H{sup -} beam acceleration above 185 MeV. Successful development of SC cavities covering the lower velocity range (down to 0.03c) is a very strong basis for the application of SC structures in the front ends of high energy linacs. Lattice design and related high-intensity beam physics issues in a {approx}400 MeV linac that uses SC cavities will be presented in this talk. In particular, axially-symmetric focusing by SC solenoids provides strong control of beam space-charge and a compact focusing lattice. As an example, we discuss the SC front-end of the H{sup -} linac for the FNAL Proton Driver.

  4. Physics design of front ends for superconducting ion linacs

    SciTech Connect (OSTI)

    Ostroumov, P.N.; /Argonne; Carneiro, J.-P.; /Fermilab

    2008-09-01T23:59:59.000Z

    Superconducting (SC) technology is the only option for CW linacs and is also an attractive option for pulsed linacs. SC cavities are routinely used for proton and H{sup -} beam acceleration above 185 MeV. Successful development of SC cavities covering the lower velocity range (down to 0.03c) is a very strong basis for the application of SC structures in the front ends of high energy linacs. Lattice design and related high-intensity beam physics issues in a {approx}400 MeV linac that uses SC cavities will be presented in this talk. In particular, axially-symmetric focusing by SC solenoids provides strong control of beam space charge and a compact focusing lattice. As an example, we discuss the SC front end of the H{sup -} linac for the FNAL Proton Driver.

  5. Towards the Light Front Variables for High Energy Production Processes

    E-Print Network [OSTI]

    N. S. Amaglobeli; S. M. Esakia; V. R. Garsevanishvili; G. O. Kuratashvili; N. K. Kutsidi; R. A. Kvatadze; Yu V. Tevzadze; T. P. Topuria

    1997-03-21T23:59:59.000Z

    Scale invariant presentation of inclusive spectra in terms of light front variables is proposed. The variables introduced go over to the well-known scaling variables x_F = 2p_z/sqrt(s) and x_T=2p_T/sqrt{s} in the high p_z and high p_T limits respectively. So Some surface is found in the phase space of produced pi-mesons in the inclusive reaction anti p p -> pi+- X at 22.4 GeV/c, which separates two groups of particles with significantly different characteristics. In one of these regions a naive statistical model seems to be in a good agreement with data, whereas it fails in the second region. Key words: Light front, inclusive, hadron-hadron, electron-positron, relativistic heavy ions, deep inelastic.

  6. Tracking thermal fronts with temperature-sensitive, chemically reactive tracers

    SciTech Connect (OSTI)

    Robinson, B.A.; Birdsell, S.A.

    1987-01-01T23:59:59.000Z

    Los Alamos is developing tracer techniques using reactive chemicals to track thermal fronts in fractured geothermal reservoirs. If a nonadsorbing tracer flowing from the injection to production well chemically reacts, its reaction rate will be a strong function of temperature. Thus the extent of chemical reaction will be greatest early in the lifetime of the system, and less as the thermal front progresses from the injection to production well. Early laboratory experiments identified tracers with chemical kinetics suitable for reservoirs in the temperature range of 75 to 100/sup 0/C. Recent kinetics studies have focused on the kinetics of hydrolysis of derivatives of bromobenzene. This class of reactions can be used in reservoirs ranging in temperature from 150 to 275/sup 0/C, which is of greater interest to the geothermal industry. Future studies will include laboratory adsorption experiments to identify possibly unwanted adsorption on granite, development of sensitive analytical techniques, and a field demonstration of the reactive tracer concept.

  7. Ionization front-driven turbulence in the clumpy interstellar medium

    E-Print Network [OSTI]

    Thomas Peters; Robi Banerjee; Ralf S. Klessen

    2008-08-20T23:59:59.000Z

    We present 3D radiation-gasdynamical simulations of an ionization front running into a dense clump. In our setup, a B0 star irradiates an overdensity which is at a distance of 10 pc and modelled as a supercritical 100 M_sol Bonnor-Ebert sphere. The radiation from the star heats up the gas and creates a shock front that expands into the interstellar medium. The shock compresses the clump material while the ionizing radiation heats it up. The outcome of this "cloud-crushing" process is a fully turbulent gas in the wake of the clump. In the end, the clump entirely dissolves. We propose that this mechanism is very efficient in creating short-living supersonic turbulence in the vicinity of massive stars.

  8. Adaptive two-regime method: Application to front propagation

    SciTech Connect (OSTI)

    Robinson, Martin, E-mail: martin.robinson@maths.ox.ac.uk; Erban, Radek, E-mail: erban@maths.ox.ac.uk [Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG (United Kingdom)] [Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG (United Kingdom); Flegg, Mark, E-mail: mark.flegg@monash.edu [School of Mathematical Sciences, Faculty of Science, Monash University Wellington Road, Clayton, Victoria 3800 (Australia)] [School of Mathematical Sciences, Faculty of Science, Monash University Wellington Road, Clayton, Victoria 3800 (Australia)

    2014-03-28T23:59:59.000Z

    The Adaptive Two-Regime Method (ATRM) is developed for hybrid (multiscale) stochastic simulation of reaction-diffusion problems. It efficiently couples detailed Brownian dynamics simulations with coarser lattice-based models. The ATRM is a generalization of the previously developed Two-Regime Method [Flegg et al., J. R. Soc., Interface 9, 859 (2012)] to multiscale problems which require a dynamic selection of regions where detailed Brownian dynamics simulation is used. Typical applications include a front propagation or spatio-temporal oscillations. In this paper, the ATRM is used for an in-depth study of front propagation in a stochastic reaction-diffusion system which has its mean-field model given in terms of the Fisher equation [R. Fisher, Ann. Eugen. 7, 355 (1937)]. It exhibits a travelling reaction front which is sensitive to stochastic fluctuations at the leading edge of the wavefront. Previous studies into stochastic effects on the Fisher wave propagation speed have focused on lattice-based models, but there has been limited progress using off-lattice (Brownian dynamics) models, which suffer due to their high computational cost, particularly at the high molecular numbers that are necessary to approach the Fisher mean-field model. By modelling only the wavefront itself with the off-lattice model, it is shown that the ATRM leads to the same Fisher wave results as purely off-lattice models, but at a fraction of the computational cost. The error analysis of the ATRM is also presented for a morphogen gradient model.

  9. A Life Cycle Assessment of a Magnesium Automotive Front End

    SciTech Connect (OSTI)

    Das, Sujit [ORNL; Dubreuil, Alain [Natural Resources Canada; Bushi, Lindita [GreenhouseGasMeasurement.com; Tharumarajah, Ambalavanar [CSIRO/CAST-CRC

    2009-01-01T23:59:59.000Z

    The Magnesium Front End Research and Development (MFERD) project under the sponsorship of Canada, China and USA aims to develop key technologies and a knowledge base for increased use of magnesium in automobile. The goal of this life cycle assessment (LCA) study is to compare the energy and potential environmental impacts of advanced magnesium based front end parts of a North America built 2007 GM-Cadillac CTS with the standard carbon steel based design. This LCA uses the 'cradle-to-grave' approach by including primary material production, semi-fabrication production, autoparts manufacturing and assembly, transportation, use phase and end-of-life processing of autoparts. This LCA study was done in compliance with international standards ISO 14040:2006 and ISO 14044:2006. Furthermore, the LCA results for aluminum based front end autopart are presented. While weight savings result in reductions in energy use and carbon dioxide emissions during the use of the car, the impacts of fabrication and recycling of lightweight materials are substantial in regard to steel. Pathways for improving sustainability of magnesium use in automobiles through material management and technology improvements including recycling are also discussed.

  10. Well-to-wheels analysis of fast pyrolysis pathways with the GREET model.

    SciTech Connect (OSTI)

    Han, J.; Elgowainy, A.; Palou-Rivera, I.; Dunn, J.B.; Wang, M.Q. (Energy Systems)

    2011-12-01T23:59:59.000Z

    The pyrolysis of biomass can help produce liquid transportation fuels with properties similar to those of petroleum gasoline and diesel fuel. Argonne National Laboratory conducted a life-cycle (i.e., well-to-wheels [WTW]) analysis of various pyrolysis pathways by expanding and employing the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The WTW energy use and greenhouse gas (GHG) emissions from the pyrolysis pathways were compared with those from the baseline petroleum gasoline and diesel pathways. Various pyrolysis pathway scenarios with a wide variety of possible hydrogen sources, liquid fuel yields, and co-product application and treatment methods were considered. At one extreme, when hydrogen is produced from natural gas and when bio-char is used for process energy needs, the pyrolysis-based liquid fuel yield is high (32% of the dry mass of biomass input). The reductions in WTW fossil energy use and GHG emissions relative to those that occur when baseline petroleum fuels are used, however, is modest, at 50% and 51%, respectively, on a per unit of fuel energy basis. At the other extreme, when hydrogen is produced internally via reforming of pyrolysis oil and when bio-char is sequestered in soil applications, the pyrolysis-based liquid fuel yield is low (15% of the dry mass of biomass input), but the reductions in WTW fossil energy use and GHG emissions are large, at 79% and 96%, respectively, relative to those that occur when baseline petroleum fuels are used. The petroleum energy use in all scenarios was restricted to biomass collection and transportation activities, which resulted in a reduction in WTW petroleum energy use of 92-95% relative to that found when baseline petroleum fuels are used. Internal hydrogen production (i.e., via reforming of pyrolysis oil) significantly reduces fossil fuel use and GHG emissions because the hydrogen from fuel gas or pyrolysis oil (renewable sources) displaces that from fossil fuel natural gas and the amount of fossil natural gas used for hydrogen production is reduced; however, internal hydrogen production also reduces the potential petroleum energy savings (per unit of biomass input basis) because the fuel yield declines dramatically. Typically, a process that has a greater liquid fuel yield results in larger petroleum savings per unit of biomass input but a smaller reduction in life-cycle GHG emissions. Sequestration of the large amount of bio-char co-product (e.g., in soil applications) provides a significant carbon dioxide credit, while electricity generation from bio-char combustion provides a large energy credit. The WTW energy and GHG emissions benefits observed when a pyrolysis oil refinery was integrated with a pyrolysis reactor were small when compared with those that occur when pyrolysis oil is distributed to a distant refinery, since the activities associated with transporting the oil between the pyrolysis reactors and refineries have a smaller energy and emissions footprint than do other activities in the pyrolysis pathway.

  11. Automatic signal processing of front monitor radar for tunneling machines

    SciTech Connect (OSTI)

    Sato, Toru [Kyoto Univ. (Japan). Dept. of Electronics and Communication] [Kyoto Univ. (Japan). Dept. of Electronics and Communication; Takeda, Kenya [NTT Co. Ltd., Chiba (Japan)] [NTT Co. Ltd., Chiba (Japan); Nagamatsu, Takashi [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)] [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan); Wakayama, Toshio [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan)] [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan); Kimura, Iwane [Osaka Inst. of Tech., Hirakata, Osaka (Japan)] [Osaka Inst. of Tech., Hirakata, Osaka (Japan); Shinbo, Tetsuya [Komatsu Co. Ltd., Kanagawa (Japan)] [Komatsu Co. Ltd., Kanagawa (Japan)

    1997-03-01T23:59:59.000Z

    It is planned to install a front monitoring impulse radar on the surface of the rotating drill of tunneling machines in order to detect obstacles such as casing pipes of vertical borings. The conventional aperture synthesis technique can no more be applied to such cases because the radar image of a pipe dies not constituent a hyperbola as is the case for linear scanning radars. The authors have developed a special purpose signal processing algorithm with the aid of the discrete model fitting method, which can be used for any pattern of scanning. The details of the algorithm are presented together with the results of numerical simulations and test site experiments.

  12. Consistent perturbative light front formulation of Yang-Mills theories

    SciTech Connect (OSTI)

    Morara, M.; Soldati, R. [Dipartimento di Fisica 'A. Righi', Universita di Bologna (Italy); McCartor, G. [Department of Physics, SMU, Dallas, Texas (United States)

    1999-11-22T23:59:59.000Z

    It is shown how to obtain the consistent light front form quantization of a non-Abelian pure Yang-Mills theory (gluondynamics) in the framework of the standard perturbative approach. After a short review of the previous attempts in the light cone gauge A{sub -}=0, it is explained how the difficulties can be overcome after turning to the anti light cone gauge A{sub +}=0. In particular, the generating functional of the renormalized Green's functions turns out to be the same as in the conventional instant form approach, leading to the Mandelstam-Leibbrandt prescription for the free gluon propagator.

  13. Instrument Front-Ends at Fermilab During Run II

    SciTech Connect (OSTI)

    Meyer, Thomas; Slimmer, David; Voy, Duane; /Fermilab

    2011-07-13T23:59:59.000Z

    The optimization of an accelerator relies on the ability to monitor the behavior of the beam in an intelligent and timely fashion. The use of processor-driven front-ends allowed for the deployment of smart systems in the field for improved data collection and analysis during Run II. This paper describes the implementation of the two main systems used: National Instruments LabVIEW running on PCs, and WindRiver's VxWorks real-time operating system running in a VME crate processor.

  14. Front surface thermal property measurements of air plasma spray coatings

    SciTech Connect (OSTI)

    Bennett, Ted; Kakuda, Tyler [University of California, Santa Barbara, California 93106-5070 (United States); Kulkarni, Anand [Siemens Energy, Orlando, Florida 32826-2399 (United States)

    2009-04-15T23:59:59.000Z

    A front-surface measurement for determining the thermal properties of thermal barrier coatings has been applied to air plasma spray coatings. The measurement is used to determine all independent thermal properties of the coating simultaneously. Furthermore, with minimal requirements placed on the sample and zero sample preparation, measurements can be made under previously impossible conditions, such as on serviceable engine parts. Previous application of this technique was limited to relatively thin coatings, where a one-dimensional heat transfer model is applied. In this paper, the influence of heat spreading on the measurement of thicker coatings is investigated with the development of a two-dimensional heat transfer model.

  15. BLM Sierra Front Field Office | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia: EnergyAvignon, France: Energy ResourcesBurleyBLM Sierra Front Field

  16. Commissioning of the SNS front-end systems at Berkeley Lab

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    COMMISSIONING OF THE SNS FRONT-END SYSTEMS AT BERKELEY LAB*Details of other MEBT commissioning efforts, especiallywere provided by LANL. Commissioning topics included beam

  17. Pion light-front wave function, parton distribution and the electromagnetic form factor

    E-Print Network [OSTI]

    Thomas Gutsche; Valery E. Lyubovitskij; Ivan Schmidt; Alfredo Vega

    2014-10-23T23:59:59.000Z

    We derive a light-front wave function of the pion, which reproduces its valence parton distribution and a electromagnetic form factor consistent with data.

  18. A. Galip Ulsoy, Mechanical Engineering Department! College of Engineering, University of Michigan at Ann Arbor!

    E-Print Network [OSTI]

    Ulsoy, A. Galip

    subsystem! ·" Role of the Driver! -" Driver state and uncertainty modeling! -" Robust steering assist! ·"Kalman filters! ·"control pressure to wheels for brake-steer! ·"Apple Quadra 800, Dell Pentium, I/O rack ! ·"several Kalman filters! ·"control of pressure to individual rear wheels for brake-steer! A high

  19. Flame front disturbance induced by a weak pressure wave

    SciTech Connect (OSTI)

    Dobashi, Ritsu; Hirano, Toshisuke; Tsuruda, Takashi [Univ. of Tokyo (Japan)

    1994-12-31T23:59:59.000Z

    An experimental study has been conducted on the effect of unburned mixture properties on flame front disturbance induced by acceleration. Experiments were performed using a rectangular combustion chamber of 80 x 80 x 440 mm. The flame front disturbance was observed in two different directions by high-speed schlieren photography. Mixtures used are of three different concentrations (C = 0.8, 1.0, and 1.25) of methane/air and two different concentrations (C = 1.0 and 1.5) of propane/air. For the methane/air mixture of C = 1.0, experiments were performed at three different initial pressures (P{sub i} = 50, 70, and 101 kPa). The observed disturbance was of a very fine structure of circular spikes, which penetrated into the burned gas. The scales of disturbance were measured and indicated to be in the range of 1.7--4.0 mm. The circular spike shape is a typical structure induced by accelerating the flame front where the density changes steeply. However, the shape of the disturbance observed for a rich propane/air mixture was not of circular spikes but of a net of ridges. For the rich propane/air mixture, the effect by preferential diffusion was remarkable and the disturbance of a different structure was generated. For the methane/air mixtures, the scale was the smallest at C = 1.0 and larger at C = 0.8 and 1.25. The scale for the propane/air mixture of C = 1.0 was slightly larger than that in the methane/air mixture of C = 1.0. The scale became larger with the decrease of the initial pressure. The measure scales were compared with the preheat zone thicknesses of corresponding flames. It was shown that the scale is closely related with the flame thickness. The scale of disturbance is found to be about 15 times as large as the preheat zone thickness.

  20. Full Hybrid: Braking

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center HomeIdle Reduction WeightRebate - LADWPPublicE85 RetailNREL

  1. Well-to-Wheels analysis of landfill gas-based pathways and their addition to the GREET model.

    SciTech Connect (OSTI)

    Mintz, M.; Han, J.; Wang, M.; Saricks, C.; Energy Systems

    2010-06-30T23:59:59.000Z

    Today, approximately 300 million standard cubic ft/day (mmscfd) of natural gas and 1600 MW of electricity are produced from the decomposition of organic waste at 519 U.S. landfills (EPA 2010a). Since landfill gas (LFG) is a renewable resource, this energy is considered renewable. When used as a vehicle fuel, compressed natural gas (CNG) produced from LFG consumes up to 185,000 Btu of fossil fuel and generates from 1.5 to 18.4 kg of carbon dioxide-equivalent (CO{sub 2}e) emissions per million Btu of fuel on a 'well-to-wheel' (WTW) basis. This compares with approximately 1.1 million Btu and 78.2 kg of CO{sub 2}e per million Btu for CNG from fossil natural gas and 1.2 million Btu and 97.5 kg of CO{sub 2}e per million Btu for petroleum gasoline. Because of the additional energy required for liquefaction, LFG-based liquefied natural gas (LNG) requires more fossil fuel (222,000-227,000 Btu/million Btu WTW) and generates more GHG emissions (approximately 22 kg CO{sub 2}e /MM Btu WTW) if grid electricity is used for the liquefaction process. However, if some of the LFG is used to generate electricity for gas cleanup and liquefaction (or compression, in the case of CNG), vehicle fuel produced from LFG can have no fossil fuel input and only minimal GHG emissions (1.5-7.7 kg CO{sub 2}e /MM Btu) on a WTW basis. Thus, LFG-based natural gas can be one of the lowest GHG-emitting fuels for light- or heavy-duty vehicles. This report discusses the size and scope of biomethane resources from landfills and the pathways by which those resources can be turned into and utilized as vehicle fuel. It includes characterizations of the LFG stream and the processes used to convert low-Btu LFG into high-Btu renewable natural gas (RNG); documents the conversion efficiencies and losses of those processes, the choice of processes modeled in GREET, and other assumptions used to construct GREET pathways; and presents GREET results by pathway stage. GREET estimates of well-to-pump (WTP), pump-to-wheel (PTW), and WTW energy, fossil fuel, and GHG emissions for each LFG-based pathway are then summarized and compared with similar estimates for fossil natural gas and petroleum pathways.

  2. Status of the warm front end of PXIE

    E-Print Network [OSTI]

    Shemyakin, A; Andrews, R; Baffes, C; Chen, A; Hanna, B; Prost, L; Saewert, G; Scarpine, V; Steimel, J; Sun, D; Li, D; D'Arcy, R

    2015-01-01T23:59:59.000Z

    A CW-compatible, pulsed H- superconducting linac is envisaged as a possible path for upgrading Fermilab's injection complex. To validate the concept of the front- end of such a machine, a test accelerator (a.k.a. PXIE) is under construction. The warm part of this accelerator comprises a 10 mA DC, 30 keV H- ion source, a 2m-long LEBT, a 2.1 MeV CW RFQ, and a 10-m long MEBT that is capable of creating a large variety of bunch structures. The paper will report commissioning results of a partially assembled LEBT, status of RFQ manufacturing, and describe development of the MEBT, in particular, of elements of its chopping system.

  3. Lattice Boltzmann BGK simulation of non-linear sound waves: The development of a shock front

    E-Print Network [OSTI]

    Boyer, Edmond

    Lattice Boltzmann BGK simulation of non-linear sound waves: The development of a shock front J. M Boltzmannsimulationsofthe development of a shock front are performed when a sound wave is emitted from a high amplitude.1088/0305-4470/33/21/305 #12;Lattice Boltzmann BGK simulation of non-linear sound waves 2 1. Introduction The lattice

  4. Fast 3D Brain Segmentation Using Dual-Front Active Contours with Optional User-Interaction

    E-Print Network [OSTI]

    Cohen, Laurent

    Fast 3D Brain Segmentation Using Dual-Front Active Contours with Optional User-Interaction Hua Li1 attributes of 3D brain segmentation algorithms in- clude robustness, accuracy, computational efficiency result. We propose a novel 3D brain cortex segmentation procedure utilizing dual- front active contours

  5. Mineral paragenesis and textures associated with sandstone-hosted roll-front uranium deposits, NW China

    E-Print Network [OSTI]

    Fayek, Mostafa

    Mineral paragenesis and textures associated with sandstone-hosted roll-front uranium deposits, NW Sciences, State Key Laboratory of Mineral Deposit Research, Nanjing University, Nanjing 210093, People, Wuyiyi and Shihongtan sandstone-hosted roll-front uranium deposits, northwest China. The mineralization

  6. The Interruption of Alpine Foehn by a Cold Front. Part I: Observations

    E-Print Network [OSTI]

    Gohm, Alexander

    propagation speed wf 1 m/s Inclination of the frontal surface is wf /uf 1/7.5 8° Freitag (1990 in valleys Interaction with local winds (e.g., foehn) foehn cold front Cold front in complex terrain ? ? #12 in Inn and Wipp Valley Temperature slope profile Doppler wind lidar in Wipp Valley #12;6 of 13 Case study

  7. Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1

    E-Print Network [OSTI]

    Showalter, Kenneth

    Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1 and Kenneth; published 14 February 2005) A wave front interaction model is developed to describe the relationship between excitability and the size and shape of stabilized wave segments in a broad class of weakly excitable media

  8. High-Level Information An Approach for Integrating Front-End and Back-End Compilers

    E-Print Network [OSTI]

    Li, Zhiyuan

    High-Level Information ­ An Approach for Integrating Front-End and Back-End Compilers Sangyeun Cho-end and back-end compilers by passing front-end information to the back-end compiler. Importing this information into an existing back- end leverages the state-of-the-art analysis and transforma- tion

  9. Hierarchical Modelling of Automotive Sensor Front-Ends For Structural Diagnosis of Aging Faults

    E-Print Network [OSTI]

    Wieringa, Roel

    h.g.kerkhoff@utwente.nl Abstract: The semiconductor industry for automotive applications is growingHierarchical Modelling of Automotive Sensor Front-Ends For Structural Diagnosis of Aging Faults, dependability, reliability, aging models, hierarchical interfacing, analogue automotive front-ends. I

  10. Observed low frequency variability of the Brazil Current front Gustavo Jorge Goni,1

    E-Print Network [OSTI]

    of the Brazil Current front. Trends of eddy kinetic energy, sea height anomaly, sea surface temperature and windObserved low frequency variability of the Brazil Current front Gustavo Jorge Goni,1 Francis Bringas; published 29 October 2011. [1] The Brazil Current is a weak western boundary current, the southwest

  11. MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI

    E-Print Network [OSTI]

    Niyogi, Dev

    MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI the shore. Key words: GALE, Coastal front, Atmospheric boundary layer, Gulf Stream, Mesoscale analysis turbulent heat fluxes. These strong gradients in heat fluxes enhance mesoscale circulation

  12. REQUIRED FOR ALL FRONT/BACK UNIVERSITY PUBLICATIONS o University of NebraskaLincoln logo (wordmark)

    E-Print Network [OSTI]

    Farritor, Shane

    REQUIRED FOR ALL FRONT/BACK UNIVERSITY PUBLICATIONS o University of Nebraska­Lincoln logo (wordmark 1 color front cover UNIVERSITY SEAL o Replace with Academic N (icon) SECONDARY LOGO o Not approved (see Toolbox p. 16 for review process) UNIVERSITY OF NEBRASKA­LINCOLN LOGO o "Lincoln" not included

  13. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOE Patents [OSTI]

    Hall, Maclin S. (Marietta, GA); Jackson, Theodore G. (Atlanta, GA); Knerr, Christopher (Lawrenceville, GA)

    1998-02-17T23:59:59.000Z

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web.

  14. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOE Patents [OSTI]

    Hall, M.S.; Jackson, T.G.; Knerr, C.

    1998-02-17T23:59:59.000Z

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web. 37 figs.

  15. SiGe receiver front ends and flip-chip integrated wideband antennas for millimeter-wave passive imaging

    E-Print Network [OSTI]

    Powell, Johnna, 1980-

    2009-01-01T23:59:59.000Z

    SiGe wideband 77-GHz and 94-GHz front end receivers with integrated antennas for passive imaging have been designed and characterized. These front end systems exhibit wideband performance with the highest gain and lowest ...

  16. Optimization Control Strategy for an Air Handling Unit with Dedicated Rotary Desiccant Dehumidification Wheel in Hot and Humid Climate

    E-Print Network [OSTI]

    Watt, J.

    2013-01-01T23:59:59.000Z

    ?Example MATHEMATICAL?MODELING Isopotential lines?(?F1?and?F2) ?1 ? ?2865 ??.??? ? 4.344??.???? ?2 ? ??.??? 6360 ? 1.127??.????? To?account?for?the?wave?front?propagation? through?the?desiccant?matrix.?Howe?[1983]?and? Jurinak [1982].?Two...?potential?functions?(F1,?F2) Ideal?process?of?absorption MATHEMATICAL?MODELING Actual?process?of?desiccant?dehumidificationDesiccant?dehumidification?process?(F1,F2)? The?F1?and?F2?isopotential lines?are?further? modified?for?non?idealities?in?the?system?by? the...

  17. Optimization Control Strategy for an Air Handling Unit with Dedicated Rotary Desiccant Dehumidification Wheel in Hot and Humid Climate 

    E-Print Network [OSTI]

    Watt, J.

    2013-01-01T23:59:59.000Z

    ?Example MATHEMATICAL?MODELING Isopotential lines?(?F1?and?F2) ?1 ? ?2865 ??.??? ? 4.344??.???? ?2 ? ??.??? 6360 ? 1.127??.????? To?account?for?the?wave?front?propagation? through?the?desiccant?matrix.?Howe?[1983]?and? Jurinak [1982].?Two...?potential?functions?(F1,?F2) Ideal?process?of?absorption MATHEMATICAL?MODELING Actual?process?of?desiccant?dehumidificationDesiccant?dehumidification?process?(F1,F2)? The?F1?and?F2?isopotential lines?are?further? modified?for?non?idealities?in?the?system?by? the...

  18. Light-Front Quantization Approach to the Gauge-Gravity Correspondence and Hadron Spectroscopy

    SciTech Connect (OSTI)

    Teramond, Guy F. de [Universidad de Costa Rica, San Jose (Costa Rica); Brodsky, Stanley J. [SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94309 (United States)

    2010-08-05T23:59:59.000Z

    We find a correspondence between semiclassical QCD quantized on the light-front and a dual gravity model in anti--de Sitter (AdS) space, thus providing an initial approximation to QCD in its strongly coupled regime. This correspondence--light-front holography--leads to a light-front Hamiltonian and relativistic bound-state wave equations that are functions of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within hadrons at equal light-front time. The eigenvalues of the resulting light-front Schroedinger and Dirac equations are consistent with the observed light meson and baryon spectrum, and the eigenmodes provide the light-front wavefunctions, the probability amplitudes describing the dynamics of the hadronic constituents. The light-front equations of motion, which are dual to an effective classical gravity theory, possess remarkable algebraic and integrability properties which are dictated by the underlying conformal properties of the theory. We extend the algebraic construction to include a confining potential while preserving the integrability of the mesonic and baryonic bound-state equations.

  19. HIGH-EFFICIENCY BACK-JUNCTION SILICON SOLAR CELL WITH AN IN-LINE EVAPORATED ALUMINUM FRONT GRID

    E-Print Network [OSTI]

    HIGH-EFFICIENCY BACK-JUNCTION SILICON SOLAR CELL WITH AN IN-LINE EVAPORATED ALUMINUM FRONT GRID M-diffused back-junction emitter. The aluminum front side grid is evaporated in an industrial-type in-thick silicon shadow masks for the in-line evaporation of the aluminum front grid. The masks are fabricated

  20. Well-to-wheels analysis of energy use and greenhouse gas emissions of plug-in hybrid electric vehicles.

    SciTech Connect (OSTI)

    Elgowainy, A.; Han, J.; Poch, L.; Wang, M.; Vyas, A.; Mahalik, M.; Rousseau, A.

    2010-06-14T23:59:59.000Z

    Plug-in hybrid electric vehicles (PHEVs) are being developed for mass production by the automotive industry. PHEVs have been touted for their potential to reduce the US transportation sector's dependence on petroleum and cut greenhouse gas (GHG) emissions by (1) using off-peak excess electric generation capacity and (2) increasing vehicles energy efficiency. A well-to-wheels (WTW) analysis - which examines energy use and emissions from primary energy source through vehicle operation - can help researchers better understand the impact of the upstream mix of electricity generation technologies for PHEV recharging, as well as the powertrain technology and fuel sources for PHEVs. For the WTW analysis, Argonne National Laboratory researchers used the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model developed by Argonne to compare the WTW energy use and GHG emissions associated with various transportation technologies to those associated with PHEVs. Argonne researchers estimated the fuel economy and electricity use of PHEVs and alternative fuel/vehicle systems by using the Powertrain System Analysis Toolkit (PSAT) model. They examined two PHEV designs: the power-split configuration and the series configuration. The first is a parallel hybrid configuration in which the engine and the electric motor are connected to a single mechanical transmission that incorporates a power-split device that allows for parallel power paths - mechanical and electrical - from the engine to the wheels, allowing the engine and the electric motor to share the power during acceleration. In the second configuration, the engine powers a generator, which charges a battery that is used by the electric motor to propel the vehicle; thus, the engine never directly powers the vehicle's transmission. The power-split configuration was adopted for PHEVs with a 10- and 20-mile electric range because they require frequent use of the engine for acceleration and to provide energy when the battery is depleted, while the series configuration was adopted for PHEVs with a 30- and 40-mile electric range because they rely mostly on electrical power for propulsion. Argonne researchers calculated the equivalent on-road (real-world) fuel economy on the basis of U.S. Environmental Protection Agency miles per gallon (mpg)-based formulas. The reduction in fuel economy attributable to the on-road adjustment formula was capped at 30% for advanced vehicle systems (e.g., PHEVs, fuel cell vehicles [FCVs], hybrid electric vehicles [HEVs], and battery-powered electric vehicles [BEVs]). Simulations for calendar year 2020 with model year 2015 mid-size vehicles were chosen for this analysis to address the implications of PHEVs within a reasonable timeframe after their likely introduction over the next few years. For the WTW analysis, Argonne assumed a PHEV market penetration of 10% by 2020 in order to examine the impact of significant PHEV loading on the utility power sector. Technological improvement with medium uncertainty for each vehicle was also assumed for the analysis. Argonne employed detailed dispatch models to simulate the electric power systems in four major regions of the US: the New England Independent System Operator, the New York Independent System Operator, the State of Illinois, and the Western Electric Coordinating Council. Argonne also evaluated the US average generation mix and renewable generation of electricity for PHEV and BEV recharging scenarios to show the effects of these generation mixes on PHEV WTW results. Argonne's GREET model was designed to examine the WTW energy use and GHG emissions for PHEVs and BEVs, as well as FCVs, regular HEVs, and conventional gasoline internal combustion engine vehicles (ICEVs). WTW results are reported for charge-depleting (CD) operation of PHEVs under different recharging scenarios. The combined WTW results of CD and charge-sustaining (CS) PHEV operations (using the utility factor method) were also examined and reported. According to the utility factor method, the share of vehicle miles trav

  1. Uranium roll front study in the upper Jackson group, Atascosa County, Texas 

    E-Print Network [OSTI]

    Miller, Michael Eugene

    1979-01-01T23:59:59.000Z

    ) that the ore zone is continually enriched by the constant migra- tion of uranium-bearing groundwater. Although roll-type deposits have sim1lar morphologies, they may form under different conditions. Iron disulfide minerals, producing the reducing... front. The ore body being examined in this study was chosen because 1t is a particularly good exposure of a roll front deposit. A roll front 1s the boundary produced when alkaline, uranium-bear1ng groundwaters encountered reducing condit1ons...

  2. Travelling fronts of the CO oxidation on Pd(111) with coverage-dependent diffusion

    SciTech Connect (OSTI)

    Cisternas, Jaime, E-mail: jecisternas@miuandes.cl [Facultad de Ingeniería y Ciencias Aplicadas, Universidad de los Andes, Monseñor Alvaro del Portillo 12455, Las Condes, Santiago (Chile); Karpitschka, Stefan [Physics of Fluids, University of Twente, Drienerlolaan 5, 7522 NB Enschede (Netherlands); Wehner, Stefan [Institut für Integrierte Naturwissenschaften - Physik, Universität Koblenz-Landau, 56070 Koblenz (Germany)

    2014-10-28T23:59:59.000Z

    In this work, we study a surface reaction on Pd(111) crystals under ultra-high-vacuum conditions that can be modeled by two coupled reaction-diffusion equations. In the bistable regime, the reaction exhibits travelling fronts that can be observed experimentally using photo electron emission microscopy. The spatial profile of the fronts reveals a coverage-dependent diffusivity for one of the species. We propose a method to solve the nonlinear eigenvalue problem and compute the direction and the speed of the fronts based on a geometrical construction in phase-space. This method successfully captures the dependence of the speed on control parameters and diffusivities.

  3. Vehicle Sideslip Estimation Design, implementation, and experimental validation

    E-Print Network [OSTI]

    Johansen, Tor Arne

    the wheel angular velocities, and a linear reference model taking the speed, steering wheel angle, Lars Imsland, Tor A. Johansen, Jens C. Kalkkuhl, and Avshalom Suissa Control systems that help the wheels from locking during hard braking, and they often have an electronic stability control system (ESC

  4. Department of Mechanical Engineering

    E-Print Network [OSTI]

    Srivastava, Kumar Vaibhav

    Explore and understand applicable science Create new materials #12;Indian Railways #12;Wheel Impact Load automated system for On-Line estimation of Wheel Impact Loads and detection of Wheel Flats of running trains Detection System (WILD) #12;Derailment Mechanism Laboratory Tests Lab Brake Mechanism Placement of Sensors

  5. Improved Reliability of PV Modules with Lexan PC Sheet-Front...

    Broader source: Energy.gov (indexed) [DOE]

    sheet application LEXAN(tm) sheet for front sheet application HYDROTHERMAL RESISTANCE OF PET AND NORYL(tm) FILM AS CORE LAYER OF BACKSHEET PET Fluoropolymer (F) PET(P) PE layer (E)...

  6. Soil water content dependent wetting front characteristics in sands T.W.J. Bautersa

    E-Print Network [OSTI]

    Walter, M.Todd

    affects wetting front instability. A series of experiments were conducted where water was infiltrated in a 0.94 cm thick, 30 cm wide, and 55 cm long polycarbonate chamber filled with clean, 20­30 (US sieve

  7. Autonomous detection and anticipation of jam fronts from messages propagated by inter-vehicle communication

    E-Print Network [OSTI]

    Sch"onhof, M; Kesting, A; Helbing, D; Sch\\"onhof, Martin; Treiber, Martin; Kesting, Arne; Helbing, Dirk

    2006-01-01T23:59:59.000Z

    In this paper, a minimalist, completely distributed freeway traffic information system is introduced. It involves an autonomous, vehicle-based jam front detection, the information transmission via inter-vehicle communication, and the forecast of the spatial position of jam fronts by reconstructing the spatiotemporal traffic situation based on the transmitted information. The whole system is simulated with an integrated traffic simulator, that is based on a realistic microscopic traffic model for longitudinal movements and lane changes. The function of its communication module has been explicitly validated by comparing the simulation results with analytical calculations. By means of simulations, we show that the algorithms for a congestion-front recognition, message transmission, and processing predict reliably the existence and position of jam fronts for vehicle equipment rates as low as 3%. A reliable mode of operation already for small market penetrations is crucial for the successful introduction of inter-...

  8. ANL/APS/TB-44, Guidelines for Beamline and Front-End Radiation...

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

    section 4. All designs of beamline and front-end components that fall within the defined envelope will not require specific additional safety review. The designs that fall outside...

  9. Experimental evaluation of the in-plane seismic behavior of store-front window systems

    E-Print Network [OSTI]

    Eva, Charles Almond

    2009-01-01T23:59:59.000Z

    of architectural glass curtain walls under in-plane loadsracking tests of curtain wall glass elements with in-planethat causes glass fallout from curtain wall and store-front

  10. This page does not print. Please use front-and-back

    E-Print Network [OSTI]

    Duchowski, Andrew T.

    This page does not print. Please use front-and-back cover layout at end of file. #12;Craig Mahaffey's astonishing to realize that the same basic knowledge used to conserve a historic submarine can be applied

  11. Detection technique and front-end RF tunable filter for cognitive radio systems

    E-Print Network [OSTI]

    Park, Sanghoon

    2010-01-01T23:59:59.000Z

    dual-mode WiMAX/WLAN direct- conversion receiver,” in Proc.Hamilton, “Aspects of direct conversion receiver design,” inand M. Ismail, “A direct conversion WiMAX RF receiver front-

  12. A survey of front end modularity as an automotive architecture and its ability to deliver value

    E-Print Network [OSTI]

    Mahé, Vincent R. (Vincent Robert)

    2008-01-01T23:59:59.000Z

    The partitioning of a system can and will dictate the creative space for a designer or engineer. This thesis will analyze how using a new automotive architecture known as a Front End Module (FEM) can affect a limited ...

  13. Vehicle Technologies Office Merit Review 2015: Magnesium-Intensive Front End Sub-Structure Development

    Broader source: Energy.gov [DOE]

    Presentation given by USAMP at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about magnesium-intensive front end sub...

  14. Hydrogen Pathways: Updated Cost, Well-to-Wheels Energy Use, and Emissions for the Current Technology Status of Ten Hydrogen Production, Delivery, and Distribution Scenarios

    SciTech Connect (OSTI)

    Ramsden, T.; Ruth, M.; Diakov, V.; Laffen, M.; Timbario, T. A.

    2013-03-01T23:59:59.000Z

    This report describes a life-cycle assessment conducted by the National Renewable Energy Laboratory (NREL) of 10 hydrogen production, delivery, dispensing, and use pathways that were evaluated for cost, energy use, and greenhouse gas (GHG) emissions. This evaluation updates and expands on a previous assessment of seven pathways conducted in 2009. This study summarizes key results, parameters, and sensitivities to those parameters for the 10 hydrogen pathways, reporting on the levelized cost of hydrogen in 2007 U.S. dollars as well as life-cycle well-to-wheels energy use and GHG emissions associated with the pathways.

  15. Non-Adiabatic Effects on Combustion Front Propagation in Porous Media: Multiplicity of Steady States

    SciTech Connect (OSTI)

    Akkutlu, I. Yucel; Yortsos, Yanis C.

    2002-03-11T23:59:59.000Z

    The sustained propagation of combustion fronts in porous media is a necessary condition for the success of an in situ combustion project for oil recovery. Compared to other recovery methods, in situ combustion involves the added complexity of exothermic reactions and temperature-dependent chemical kinetics. In the presence of heat losses, the possibility of ignition and extinction (quenching) exists. In this report, we address the properties of combustion fronts propagating at a constant velocity in the presence of heat losses.

  16. The Communist revolution in Republican China: the conceptual development of the second united front.

    E-Print Network [OSTI]

    Hope, Brian Lannes

    1974-01-01T23:59:59.000Z

    THE COMMUNIS( RE'JOLUT ION IN REPUBL ICAN CHINA: THE CONCEPTUAL DEVELOPMENT OF THE SECOND UNITED FRONT A Thesis by BRIAN LANNES HOPE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement... for the degree oi MASTER OF ARTS December, 1974 Major Subject: Political Science THE COMMUNIST REVOLUTION IN REPUBLICAN CHINA: THE CONCEPTUAL DEVELOPMENT OF THE SECOND UNITED FRONT A Thesis by BRIAN LANNES HOPE Approved as to style and content by: +~9...

  17. Light-Front Quantization Approach to the Gauge Gravity Correspondence and Hadron Spectroscopy

    SciTech Connect (OSTI)

    de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC

    2010-05-26T23:59:59.000Z

    We find a correspondence between semiclassical QCD quantized on the light-front and a dual gravity model in anti-de Sitter (AdS) space, thus providing an initial approximation to QCD in its strongly coupled regime. This correspondence - light-front holography - leads to a light-front Hamiltonian and relativistic bound-state wave equations that are functions of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within hadrons at equal lightfront time. The eigenvalues of the resulting light-front Schrodinger and Dirac equations are consistent with the observed light meson and baryon spectrum, and the eigenmodes provide the light-front wavefunctions, the probability amplitudes describing the dynamics of the hadronic constituents. The light-front equations of motion, which are dual to an effective classical gravity theory, possess remarkable algebraic and integrability properties which are dictated by the underlying conformal properties of the theory. We extend the algebraic construction to include a confining potential while preserving the integrability of the mesonic and baryonic bound-state equations.

  18. The Wheel Turns 

    E-Print Network [OSTI]

    Piacentini, Valerie

    1977-01-01T23:59:59.000Z

    in the street. IIJim, corne herso I wBnt to telk to yoU.'I Kirk cems over and knelt 8t Spock's feet, resting hL.;) erms on th(:) Vul can IS knee-3 9 end looking up anxiously into his feee. "What is it, Spack? Have I done something '"rang?" "Of course not...

  19. The Wheel Turns

    E-Print Network [OSTI]

    Piacentini, Valerie

    1977-01-01T23:59:59.000Z

    in the street. IIJim, corne herso I wBnt to telk to yoU.'I Kirk cems over and knelt 8t Spock's feet, resting hL.;) erms on th(:) Vul can IS knee-3 9 end looking up anxiously into his feee. "What is it, Spack? Have I done something '"rang?" "Of course not...

  20. The Wheel of Fate

    E-Print Network [OSTI]

    Piacentini, Valerie, with poetry by Sheila Clark

    1980-01-01T23:59:59.000Z

    .r relati.onshi.p had altered. Spock found it came naturally to think of 'Jim'. He spoke the name aloud, and it fell eas,ily from his lips, a name he rarely used in normal circumstances. Now he was in command; on Spock alone rested the responsibility... courage faltered. Then his customary cool logiC reasserted itself. It must be done, therefore it would be done; Jim's safety depended on it, and he would not permit himself to fail. He began to plan. 'l'hey must leave this house soon. It had pr...

  1. Of Wings and Wheels 

    E-Print Network [OSTI]

    Wood, Alice

    2007-01-01T23:59:59.000Z

    . Cherubim are intimately connected with the manifestation of Yahweh and have an apotropaic function in relation to sacred space. They are envisaged with one face and one set of wings. Ps 18:11 = 2 Sam 22:11 suggests that they are quadrupedal...

  2. Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

    DOE Patents [OSTI]

    Battiste, Richard L

    2013-12-31T23:59:59.000Z

    Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into th emold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with a fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a termperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into th emold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

  3. Localized structures and front propagation in the Lengyel-Epstein model

    SciTech Connect (OSTI)

    Jensen, O.; Pannbacker, V.O.; Mosekilde, E.; Dewel, G.; Borckmans, P. (Physics Department, Technical University of Denmark, 2800 Lyngby (Denmark) Service de Chimie-Physique, Code Postal 231 Universite Libre de Bruxelles, 1050 Brussels (Belgium))

    1994-08-01T23:59:59.000Z

    Pattern selection, localized structure formation, and front propagation are analyzed within the framework of a model for the chlorine dioxide--iodine--malonic acid reaction that represents a key to understanding recently obtained Turing structures. This model is distinguished from previously studied, simple reaction-diffusion models by producing a strongly subcritical transition to stripes. The wave number for the modes of maximum linear gain is calculated and compared with the dominant wave number for the finally selected, stationary structures grown from the homogeneous steady state or developed behind a traveling front. The speed of propagation for a front between the homogeneous steady state and a one-dimensional (1D) Turing structure is obtained. This velocity shows a characteristic change in behavior at the crossover between the subcritical and supercritical regimes for the Turing bifurcation. In the subcritical regime there is an interval where the front velocity vanishes as a result of a pinning of the front to the underlying structure. In 2D, two different nucleation mechanisms for hexagonal structures are illustrated on the Lengyel-Epstein and the Brusselator model. Finally, the observation of 1D and 2D spirals with Turing-induced cores is reported.

  4. Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

    DOE Patents [OSTI]

    Battiste, Richard L. (Oak Ridge, TN)

    2007-12-25T23:59:59.000Z

    Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

  5. Gauge/Gravity Duality and Strongly Coupled Light-Front Dynamics

    SciTech Connect (OSTI)

    de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins

    2011-08-12T23:59:59.000Z

    We find a correspondence between semiclassical gauge theories quantized on the light-front and a dual gravity model in anti-de Sitter (AdS) space, thus providing an initial approximation to QCD in its strongly coupled regime. This correspondence - light-front holography - leads to a light-front Hamiltonian and relativistic bound-state wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. Light-front holography also allows a precise mapping of transition amplitudes from AdS to physical space-time. In contrast with the usual AdS/QCD framework, the internal structure of hadrons is explicitly introduced in the gauge/gravity correspondence and the angular momentum of the constituents plays a key role. We also discuss how to introduce higher Fock-states in the correspondence as well as their relevance for describing the detailed structure of space and time-like form factors.

  6. Deep Chandra observation and numerical studies of the nearest cluster cold front in the sky

    E-Print Network [OSTI]

    Werner, N; Zhuravleva, I; Ichinohe, Y; Simionescu, A; Allen, S W; Markevitch, M; Fabian, A C; Keshet, U; Roediger, E; Ruszkowski, M; Sanders, J S

    2015-01-01T23:59:59.000Z

    We present the results of a very deep (500 ks) Chandra observation, along with tailored numerical simulations, of the nearest, best resolved cluster cold front in the sky, which lies 90 kpc (19 arcmin) to the northwest of M 87. The northern part of the front appears the sharpest, with a width smaller than 2.5 kpc (1.5 Coulomb mean free paths; at 99 per cent confidence). Everywhere along the front, the temperature discontinuity is narrower than 4-8 kpc and the metallicity gradient is narrower than 6 kpc, indicating that diffusion, conduction and mixing are suppressed across the interface. Such transport processes can be naturally suppressed by magnetic fields aligned with the cold front. However, the northwestern part of the cold front is observed to have a nonzero width. The broadening is consistent with the presence of Kelvin-Helmholtz instabilities (KHI) on length scales of a few kpc. Based on comparison with simulations, the presence of KHI would imply that the effective viscosity of the intra-cluster medi...

  7. Well-to-wheels energy use and greenhouse gas emissions analysis of plug-in hybrid electric vehicles.

    SciTech Connect (OSTI)

    Elgowainy, A.; Burnham, A.; Wang, M.; Molburg, J.; Rousseau, A.; Energy Systems

    2009-03-31T23:59:59.000Z

    Researchers at Argonne National Laboratory expanded the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model and incorporated the fuel economy and electricity use of alternative fuel/vehicle systems simulated by the Powertrain System Analysis Toolkit (PSAT) to conduct a well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW results were separately calculated for the blended charge-depleting (CD) and charge-sustaining (CS) modes of PHEV operation and then combined by using a weighting factor that represented the CD vehicle-miles-traveled (VMT) share. As indicated by PSAT simulations of the CD operation, grid electricity accounted for a share of the vehicle's total energy use, ranging from 6% for a PHEV 10 to 24% for a PHEV 40, based on CD VMT shares of 23% and 63%, respectively. In addition to the PHEV's fuel economy and type of on-board fuel, the marginal electricity generation mix used to charge the vehicle impacted the WTW results, especially GHG emissions. Three North American Electric Reliability Corporation regions (4, 6, and 13) were selected for this analysis, because they encompassed large metropolitan areas (Illinois, New York, and California, respectively) and provided a significant variation of marginal generation mixes. The WTW results were also reported for the U.S. generation mix and renewable electricity to examine cases of average and clean mixes, respectively. For an all-electric range (AER) between 10 mi and 40 mi, PHEVs that employed petroleum fuels (gasoline and diesel), a blend of 85% ethanol and 15% gasoline (E85), and hydrogen were shown to offer a 40-60%, 70-90%, and more than 90% reduction in petroleum energy use and a 30-60%, 40-80%, and 10-100% reduction in GHG emissions, respectively, relative to an internal combustion engine vehicle that used gasoline. The spread of WTW GHG emissions among the different fuel production technologies and grid generation mixes was wider than the spread of petroleum energy use, mainly due to the diverse fuel production technologies and feedstock sources for the fuels considered in this analysis. The PHEVs offered reductions in petroleum energy use as compared with regular hybrid electric vehicles (HEVs). More petroleum energy savings were realized as the AER increased, except when the marginal grid mix was dominated by oil-fired power generation. Similarly, more GHG emissions reductions were realized at higher AERs, except when the marginal grid generation mix was dominated by oil or coal. Electricity from renewable sources realized the largest reductions in petroleum energy use and GHG emissions for all PHEVs as the AER increased. The PHEVs that employ biomass-based fuels (e.g., biomass-E85 and -hydrogen) may not realize GHG emissions benefits over regular HEVs if the marginal generation mix is dominated by fossil sources. Uncertainties are associated with the adopted PHEV fuel consumption and marginal generation mix simulation results, which impact the WTW results and require further research. More disaggregate marginal generation data within control areas (where the actual dispatching occurs) and an improved dispatch modeling are needed to accurately assess the impact of PHEV electrification. The market penetration of the PHEVs, their total electric load, and their role as complements rather than replacements of regular HEVs are also uncertain. The effects of the number of daily charges, the time of charging, and the charging capacity have not been evaluated in this study. A more robust analysis of the VMT share of the CD operation is also needed.

  8. Front-flash thermal imaging characterization of continuous fiber ceramic composites.

    SciTech Connect (OSTI)

    Deemer, C.

    1999-04-23T23:59:59.000Z

    Infrared thermal imaging has become increasingly popular as a nondestructive evaluation method for characterizing materials and detecting defects. One technique, which was utilized in this study, is front-flash thermal imaging. We have developed a thermal imaging system that uses this technique to characterize advanced material systems, including continuous fiber ceramic composite (CFCC) components. In a front-flash test, pulsed heat energy is applied to the surface of a sample, and decay of the surface temperature is then measured by the thermal imaging system. CFCC samples with drilled flat-bottom holes at the back surface (to serve as ''flaws'') were examined. The surface-temperature/time relationship was analyzed to determine the depths of the flaws from the front surface of the CFCC material. Experimental results on carbon/carbon and CFCC samples are presented and discussed.

  9. Front-end Electronics Test for the LHCb Muon Wire Chambers

    E-Print Network [OSTI]

    Nobrega, R; Carboni, G; Massafferri, A; Santovetti, E

    2007-01-01T23:59:59.000Z

    This document describes the apparatus and procedures implemented to test Multi Wire Proportional Chambers (MWPC) after front-end assembly for the LHCb Muon Detector. Results of measurements of key noise parameters are also described. Given a fully equipped chamber, this system is able to diagnose every channel performing an analysis of front-end output drivers’ response and noise rate versus threshold. Besides, it allows to assess if the noise rate at the experiment threshold region is within appropriate limits. Aiming at an automatic, fast and user-friendly system for mass production tests of MWPC, the project has foreseen as well electronic identification of every chamber and front-end board, and data archiving in such a way to make it available to the Experiment Control System (ECS) while in operation.

  10. Report on the value engineering workshop on APS beamline front ends

    SciTech Connect (OSTI)

    Kuzay, T.

    1993-01-01T23:59:59.000Z

    A formal value engineering evaluation process was developed to address the front end components of the beamlines for the Advanced Photon Source (APS). This process (described in Section 2) involved an information phase, a creative phase, a judgment phase, a development phase, and a recommendation phase. Technical experts from other national laboratories and industry were invited to a two-day Value Engineering Workshop on November 5-6, 1992. The results of this Workshop are described in Section 4. Following the Workshop, various actions by the APS staff led to the redesign of the front end components, which are presented in Sections 5 and 6. The cost benefit analysis is presented in Section 7. It is important of realize that an added benefit of the Workshop was to obtain numerous design evaluations and enhancements of the front end components by experts in the field. As the design work proceeds to Title II completion, the APS staff is including many of these suggestions.

  11. The Wave-Front Correction System for the Sunrise Balloon-Borne Solar Observatory

    E-Print Network [OSTI]

    Berkefeld, T; Soltau, D; Bell, A; Doerr, H P; Feger, B; Friedlein, R; Gerber, K; Heidecke, F; Kentischer, T; Lühe, O v d; Sigwarth, M; Wälde, E; Barthol, P; Deutsch, W; Gandorfer, A; Germerott, D; Grauf, B; Meller, R; Alvarez-Herrero, A; Knölker, M; Pillet, V Martinez; Solanki, S K; Title, A M

    2010-01-01T23:59:59.000Z

    This paper describes the wave-front correction system developed for the Sunrise balloon telescope, and provides information about its in-flight performance. For the correction of low-order aberrations, a Correlating Wave-Front Sensor (CWS) was used. It consisted of a six-element Shack-Hartmann wave-front sensor (WFS), a fast tip-tilt mirror for the compensation of image motion, and an active telescope secondary mirror for focus correction. The CWS delivered a stabilized image with a precision of 0.04 arcsec (rms), whenever the coarse pointing was better than 90 arcsec peak-to-peak. The automatic focus adjustment maintained a focus stability of 0.01 waves in the focal plane of the CWS. During the 5.5 day flight, good image quality and stability was achieved during 33 hours, containing 45 sequences that lasted between 10 and 45 minutes.

  12. Apparatus and method for phase fronts based on superluminal polarization current

    DOE Patents [OSTI]

    Singleton, John (Los Alamos, NM); Ardavan, Houshang (Cambridge, GB); Ardavan, Arzhang (Cambridge, GB)

    2012-02-28T23:59:59.000Z

    An apparatus and method for a radiation source involving phase fronts emanating from an accelerated, oscillating polarization current whose distribution pattern moves superluminally (that is, faster than light in vacuo). Theoretical predictions and experimental measurements using an existing prototype superluminal source show that the phase fronts from such a source can be made to be very complex. Consequently, it will be very difficult for an aircraft imaged by such a radiation to detect where this radiation has come from. Moreover, the complexity of the phase fronts makes it almost impossible for electronics on an aircraft to synthesize a rogue reflection. A simple directional antenna and timing system should, on the other hand, be sufficient for the radar operators to locate the aircraft, given knowledge of their own source's speed and modulation pattern.

  13. Light-front representation of chiral dynamics in peripheral transverse densities

    E-Print Network [OSTI]

    Granados, C

    2015-01-01T23:59:59.000Z

    The nucleon's electromagnetic form factors are expressed in terms of the transverse densities of charge and magnetization at fixed light-front time. At peripheral transverse distances $b = O(M_\\pi^{-1})$ the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). We represent the leading-order chiral EFT results for the peripheral transverse densities as overlap integrals of chiral light-front wave functions, describing the transition of the initial nucleon to soft pion-nucleon intermediate states and back. The new representation (a) explains the parametric order of the peripheral transverse densities; (b) establishes an inequality between the spin-independent and -dependent densities; (c) exposes the role of pion orbital angular momentum in chiral dynamics; (d) reveals a large left-right asymmetry of the current in a transversely polarized nucleon and suggests a simple interpretation. The light-front representation enables a first-quantiz...

  14. Dynamical model for longitudinal wave functions in light-front holographic QCD

    SciTech Connect (OSTI)

    Chabysheva, Sophia S.; Hiller, John R., E-mail: jhiller@d.umn.edu

    2013-10-15T23:59:59.000Z

    We construct a Schrödinger-like equation for the longitudinal wave function of a meson in the valence qq{sup -bar} sector, based on the ’t Hooft model for large-N two-dimensional QCD, and combine this with the usual transverse equation from light-front holographic QCD, to obtain a model for mesons with massive quarks. The computed wave functions are compared with the wave function ansatz of Brodsky and de Téramond and used to compute decay constants and parton distribution functions. The basis functions used to solve the longitudinal equation may be useful for more general calculations of meson states in QCD. -- Highlights: •Provide relativistic quark model based on light-front holographic QCD. •Incorporate dependence on quark mass. •Consistent with the Brodsky–de Téramond quark-wave-function ansatz. •Compute meson decay constants and parton distribution functions. •Illustrate use of basis functions that could be convenient for more general numerical calculations in light-front QCD.

  15. Light-Front Dynamic Analysis of Bound States in Scalar Field Model

    E-Print Network [OSTI]

    Chueng-Ryong Ji; Yukihisa Tokunaga

    2012-05-16T23:59:59.000Z

    The light-front dynamics (LFD) of the scalar field model theory is analyzed to solve the two-body bound-state problem. The light-front two-body bound-state equation is extended to the full LFD kernel including the ladder, cross-ladder, stretched-box, and particle-antiparticle creation/annihilation effects to study the contributions of higher Fock-states. The light-front two-body equation is also modified by the term corresponding to the self-energy corrections and counter-terms. Using the variational principle, we obtain the numerical result of the binding energy B versus the coupling constant \\alpha\\ for various mass ratios of the constituent particles including the cases of non-zero exchange particle mass. We also discuss the correlation between the mass spectrum and the corresponding bound-state wavefunction.

  16. Measures of the Environmental Footprint of the Front End of the Nuclear Fuel Cycle

    SciTech Connect (OSTI)

    Brett Carlsen; Emily Tavrides; Erich Schneider

    2010-08-01T23:59:59.000Z

    Previous estimates of environmental impacts associated with the front end of the nuclear fuel cycle have focused primarily on energy consumption and CO2 emissions. Results have varied widely. Section 2 of this report provides a summary of historical estimates. This study revises existing empirical correlations and their underlying assumptions to fit to a more complete set of existing data. This study also addresses land transformation, water withdrawals, and occupational and public health impacts associated with the processes of the front end of the once-through nuclear fuel cycle. These processes include uranium mining, milling, refining, conversion, enrichment, and fuel fabrication. Metrics are developed to allow environmental impacts to be summed across the full set of front end processes, including transportation and disposition of the resulting depleted uranium.

  17. CW Room Temperature Re-Buncher for the Project X Front End

    SciTech Connect (OSTI)

    Romanov, Gennady; Awida, Mohamed H.; Chen, Meiyu; Gonin, Ivan V.; Kazakov, Sergey; Kostin, Roman; Lebedev, Valeri; Solyak, Nikolay; Yakovlev, Vyacheslav P.; /Fermilab

    2012-05-09T23:59:59.000Z

    At Fermilab there is a plan to construct the Project X Injector Experiment (PXIE) facility - a prototype of the front end of the Project X, a multi-MW proton source based on superconducting linac. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The room temperature front end of the linac contains an ion source, an RFQ accelerator and a Medium Energy Beam Transport (MEBT) section comprising a high bandwidth bunch selective chopper. The MEBT length is about 10 m, so three re-bunching CW cavities are used to support the beam longitudinal dynamics. The paper reports a RF design of the re-bunchers along with preliminary beam dynamic and thermal analysis of the cavities.

  18. Comparison of quantum field perturbation theory for the light front with the theory in lorentz coordinates

    E-Print Network [OSTI]

    S. A. Paston; V. A. Franke

    1999-01-22T23:59:59.000Z

    The relationship between the perturbation theory in light-front coordinates and Lorentz-covariant perturbation theory is investigated. A method for finding the difference between separate terms of the corresponding series without their explicit evaluation is proposed. A procedure of constructing additional counter-terms to the canonical Hamiltonian that compensate this difference at any finite order is proposed. For the Yukawa model, the light-front Hamiltonian with all of these counter-terms is obtained in a closed form. Possible application of this approach to gauge theories is discussed.

  19. Eddy conductivity in and near dry cold fronts in the layer, 70 to 1270 feet 

    E-Print Network [OSTI]

    Conlan, Edward Francis

    1965-01-01T23:59:59.000Z

    EDDY CONDUCTIVITY IN AND NEAR DRY COLD FRONTS IN THE LAYER, 70 TO 1270 FEET A Thesis By EDWARD FRANCIS CONLAN Captain, USAF Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE January 1965 Major Subject: METEOROLOGY EDDY CONDUCTIVITY IN AND NEAR DRY COLD FRONTS IN THE LAYER) 70 TO 1270 FEET A Thesis By EDWARD FRANCIS CONLAN Captain, USAF Approved as to style and content by: i J 8~. . c6~h arrmanf o...

  20. Upper and lower limits on the Crab pulsar's astrophysical parameters set from gravitational wave observations by LIGO: braking index and energy considerations

    E-Print Network [OSTI]

    Giovanni Santostasi

    2008-07-16T23:59:59.000Z

    The Laser Interferometer Gravitational Observatory (LIGO) has recently reached the end of its fifth science run (S5), having collected more than a year worth of data. Analysis of the data is still ongoing but a positive detection of gravitational waves, while possible, is not realistically expected for most likely sources. This is particularly true for what concerns gravitational waves from known pulsars. In fact, even under the most optimistic (and not very realistic) assumption that all the pulsar's observed spin-down is due to gravitational waves, the gravitational wave strain at earth from all the known isolated pulsars (with the only notable exception of the Crab pulsar) would not be strong enough to be detectable by existing detectors. By August 2006, LIGO had produced enough data for a coherent integration capable to extract signal from noise that was weaker than the one expected from the Crab pulsar's spin-down limit. No signal was detected, but beating the spin-down limit is a considerable achievement for the LIGO Scientific Collaboration (LSC). It is customary to translate the upper limit on strain from a pulsar into a more astrophysically significant upper limit on ellipticity. Once the spin-down limit has been beaten, it is possible to release the constraint that all the spin-down is due to gravitational wave emission. A more complete model with diverse braking mechanisms can be used to set limits on several astrophysical parameters of the pulsar. This paper shows possible values of such parameters for the Crab pulsar given the current limit on gravitational waves from this neutron star.

  1. Cost of Ownership and Well-to-Wheels Carbon Emissions/Oil Use of Alternative Fuels and Advanced Light-Duty Vehicle Technologies

    SciTech Connect (OSTI)

    Elgowainy, Mr. Amgad [Argonne National Laboratory (ANL); Rousseau, Mr. Aymeric [Argonne National Laboratory (ANL); Wang, Mr. Michael [Argonne National Laboratory (ANL); Ruth, Mr. Mark [National Renewable Energy Laboratory (NREL); Andress, Mr. David [David Andress & Associates, Inc.; Ward, Jacob [U.S. Department of Energy; Joseck, Fred [U.S. Department of Energy; Nguyen, Tien [U.S. Department of Energy; Das, Sujit [ORNL

    2013-01-01T23:59:59.000Z

    The U.S. Department of Energy (DOE), Argonne National Laboratory (Argonne), and the National Renewable Energy Laboratory (NREL) updated their analysis of the well-to-wheels (WTW) greenhouse gases (GHG) emissions, petroleum use, and the cost of ownership (excluding insurance, maintenance, and miscellaneous fees) of vehicle technologies that have the potential to significantly reduce GHG emissions and petroleum consumption. The analyses focused on advanced light-duty vehicle (LDV) technologies such as plug-in hybrid, battery electric, and fuel cell electric vehicles. Besides gasoline and diesel, alternative fuels considered include natural gas, advanced biofuels, electricity, and hydrogen. The Argonne Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) and Autonomie models were used along with the Argonne and NREL H2A models.

  2. A 65nm CMOS Ultra Low Power and Low Noise 131M Front-End Transimpedance Amplifier

    E-Print Network [OSTI]

    Ayers, Joseph

    A 65nm CMOS Ultra Low Power and Low Noise 131M Front-End Transimpedance Amplifier Jiaping Hu and simulation of a high-transimpedance gain, ultra low-power dissipation and low-noise CMOS front- end control [3]. However, it introduces design challenges in the form of trade-offs between noise, power

  3. Design of a Very Low-power, Low-cost 60 GHz Receiver Front-End Implemented

    E-Print Network [OSTI]

    Boyer, Edmond

    Design of a Very Low-power, Low-cost 60 GHz Receiver Front-End Implemented in 65 nm CMOS Technology- noise amplifier (LNA), mixer, a voltage controlled oscillator (VCO), a local oscillator (LO) buffer, France The research on the design of receiver front-ends for very high data-rate communication in the 60

  4. December 1, 2000 / Vol. 25, No. 23 / OPTICS LETTERS 1687 Hybrid curvature and gradient wave-front sensor

    E-Print Network [OSTI]

    Dainty, Chris

    Received July 26, 2000 A new wave-front sensor for adaptive optics that gives signals for the curvatureDecember 1, 2000 / Vol. 25, No. 23 / OPTICS LETTERS 1687 Hybrid curvature and gradient wave-front sensor C. Paterson and J. C. Dainty The Blackett Laboratory, Imperial College, London, SW7 2BZ, UK

  5. Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG AND FUQING ZHANG

    E-Print Network [OSTI]

    Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG of mesoscale gravity waves to the baroclinicity of the background jet-front systems by simulating different life cycles of baroclinic waves with a high-resolution mesoscale model. Four simulations are made

  6. Rapid uplift of nonmethane hydrocarbons in a cold front over central Europe

    E-Print Network [OSTI]

    Hoskins, Brian

    Rapid uplift of nonmethane hydrocarbons in a cold front over central Europe R. M. Purvis,1 A. C of 21 C2­C7 nonmethane hydrocarbons (NMHCs) has been determined in planetary boundary layer (PBL between the PBL and FT was observed for all short and medium lifetime hydrocarbons (e.g., average iso

  7. Sensitivity of mesoscale gravity waves to the baroclinicity of jet-front systems 

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12T23:59:59.000Z

    To investigate the generation of mesoscale gravity waves from upper-tropospheric jet-front systems, five different life cycles of baroclinic waves are simulated with a high-resolution mesoscale model (MM5 with 10-km grid spacing). The baroclinicity...

  8. Crawling Along the Pareto Front: Tales From the Practice Martina Hasenjager

    E-Print Network [OSTI]

    Coello, Carlos A. Coello

    Crawling Along the Pareto Front: Tales From the Practice Martina Hasenj¨ager Honda Research Institute Europe GmbH Carl-Legien-Str. 30 63073 Offenbach, Germany martina.hasenjaeger@honda-ri.de Bernhard Sendhoff Honda Research Institute Europe GmbH Carl-Legien-Str. 30 63073 Offenbach, Germany bs@honda

  9. adaptive optics wave-front: Topics by E-print Network

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

    adaptive optics wave-front First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Laboratory adaptive optics...

  10. Fluid Dynamics Research 33 (2003) 173189 The distortion of weak fronts by mesoscale orography

    E-Print Network [OSTI]

    Hunt, Julian

    University of Technology, Delft, NL c Environment Centre, University of Leeds, Leeds LS2 9JT, UK d Department the surface of the orography, that a narrow portion of the front eventually overturns, leading to enhanced and the localised overturning process is examined within an analytical framework. c 2003 Published by The Japan

  11. Green radio despite "Dirty RF" front-end Myriam Ariaudo*1

    E-Print Network [OSTI]

    Fijalkow, Inbar

    Green radio despite "Dirty RF" front-end Myriam Ariaudo*1 , Inbar Fijalkow1 , Jean-Luc Gautier1 in order to contribute in a Green radio development. In fact, the effects of typical RF imperfections, like algorithms are applied. Such algorithms enable Green applications (e.g., Orthogonal Frequency Division

  12. A FREEWARE PROGRAM FOR PRECISE OPTICAL ANALYSIS OF THE FRONT SURFACE OF A SOLAR CELL

    E-Print Network [OSTI]

    A FREEWARE PROGRAM FOR PRECISE OPTICAL ANALYSIS OF THE FRONT SURFACE OF A SOLAR CELL Simeon C. Baker-Finch and Keith R. McIntosh Centre for Sustainable Energy Systems, Australian National University, Canberra, ACT 0200, AUSTRALIA Tel: +61-2-6125-8966, Fax: +61-2-6125-8873, Email: simeon

  13. CURB APPEAL: The importance of the "front porch" Universities, including SMU, hope athletic success influences application

    E-Print Network [OSTI]

    Slatton, Clint

    CURB APPEAL: The importance of the "front porch" Universities, including SMU, hope athletic success influences application numbers and campus culture Chris Dell, Sports Editor, cdell@smu.edu Issue date: 5 and wealthy donors pump millions each year into important athletic programs. SMU's donors raised Gerald J

  14. Electronics of the 1.5m fiber echelle front-end module A. Tokovinin

    E-Print Network [OSTI]

    Tokovinin, Andrei A.

    Electronics cabinet Relays Motorcontroller DB9DB9 Buffer Front-end module Lamps ThAr & Q. Fiber On/Off LED TV inside the FEM. · Powering the Th-Ar comparison lamp during comparison-spectra exposures. This hollow-cathode lamp needs a high voltage (200 V) and a current of 10 ma (max. current 20 ma). As the lamp lifetime

  15. Stability of planar reactive fronts in external fields Arkady B. Rovinsky,* Anatol M. Zhabotinsky,

    E-Print Network [OSTI]

    Epstein, Irving R.

    in reactive systems due to external fields such as electric fields or pressure gradients, may significantlyStability of planar reactive fronts in external fields Arkady B. Rovinsky,* Anatol M. Zhabotinsky arise naturally in systems sub- jected to external fields, such as electric fields or pressure gradients

  16. Hartmut Sadrozinski RD50 5/06/04 Development of Radiation-hard Front Electronics

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    -hard, low power, ideal for pixels Bipolar : power-noise advantages for large capacitances and fast shapingGe Bipolar vs. CMOS Power required for a front-end amplifier designed with a 20ns shaping time (ATLAS SCT/3 of the power of the CMOS version for the same noise performance. For shorter shaping times, the advantage would

  17. 2 Bainitic Ferrite The growth of pearlite occurs at a common transformation front with the

    E-Print Network [OSTI]

    Cambridge, University of

    2 Bainitic Ferrite The growth of pearlite occurs at a common transformation front with the austenite. The growth of the ferrite and cementite phases is coupled and their compositions are complementary since the carbon which cannot be accommodated by the ferrite is incorporated into the cementite

  18. Zero modes in the light-front coupled-cluster method

    SciTech Connect (OSTI)

    Chabysheva, Sophia S.; Hiller, John R., E-mail: jhiller@d.umn.edu

    2014-01-15T23:59:59.000Z

    The light-front coupled-cluster (LFCC) method is a technique for solving Hamiltonian eigenvalue problems in light-front-quantized field theories. Its primary purpose is to provide a systematic sequence of solvable approximations to the original eigenvalue problem without the truncation of Fock space. Here we discuss the incorporation of zero modes, modes of zero longitudinal momentum, into the formalism of the method. Without zero modes, the light-front vacuum is trivial, and the vacuum expectation value of the field is always zero. The LFCC method with zero modes provides for vacuum structure, in the form of a generalized coherent state of zero modes, as is illustrated here in two-dimensional model field theories. -- Highlights: •Extends the light-front coupled-cluster method to include zero modes. •Illustrates with an analysis of vacuum structure for phi-3, phi-4, and Wick–Cutkosky model field theories. •Demonstrates the applicability of the LFCC method to theories with spontaneous symmetry breaking.

  19. Export of Asian pollution during two cold front episodes of the TRACE-P experiment

    E-Print Network [OSTI]

    Palmer, Paul

    Export of Asian pollution during two cold front episodes of the TRACE-P experiment C. Mari how these cyclonic systems have impacted the export of pollution out of the Asian continent. We of pollution are met during flight 13 (i.e., the occurrences of the warm conveyor belt near the source regions

  20. Low-Frequency Variability in the Midlatitude Baroclinic Atmosphere Induced by an Oceanic Thermal Front

    E-Print Network [OSTI]

    Ghil, Michael

    oscillatory modes dominate. As the two layers become nearly equal, antisymmetric oscillatory modes become of the atmospheric marine boundary layer (AMBL) to oceanic fronts has been studied in observations, as well's dynamics depends on the layer-depth ratio. When the model is nearly equivalent-barotropic, symmetric

  1. Scaling Variables and Stability of Hyperbolic Fronts Th. Gallay and G. Raugel

    E-Print Network [OSTI]

    Scaling Variables and Stability of Hyperbolic Fronts Th. Gallay and G. Raugel CNRS et Universit'e de Paris­Sud URA 760, Analyse Num'erique et EDP Bâ??atiment 425 F­91405 Orsay Cedex, France Thierry.Gallay

  2. Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland

    E-Print Network [OSTI]

    Tsai, Victor C.

    Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland Ian Glaciers, Greenland, from 2001 to 2006, a period in which they retreated and sped up. These data show and retreat in less than a century indicates that tidewater glaciers in Greenland can advance rapidly

  3. LIDAR OBSERVATIONS AND COMPARISON WITH NUMERICAL SIMULATION OF A LAKE MICHIGAN LAND BREEZE FRONT

    E-Print Network [OSTI]

    Eloranta, Edwin W.

    of the Lake-Induced Convection Experiments (Lake-ICE), on December 21, 1997 the University of Wisconsin VolumeLIDAR OBSERVATIONS AND COMPARISON WITH NUMERICAL SIMULATION OF A LAKE MICHIGAN LAND BREEZE FRONT G circulation over Lake Michigan. Backscatter returns revealed a steady offshore flow extending 1.5 to 4 km

  4. Numerical study of the diapycnal flow through a tidal front with passive tracers

    E-Print Network [OSTI]

    Dong, Changming "Charles"

    . This qualitatively agrees with a recent field experiment using a dye tracer on Georges Bank. Additional experiments are performed to investigate the sensitivity of the tracer dispersion to the tidal phase and the location, the previous studies indicated Eulerian cross-front mean circu- lation maybe is in a multiple-cell structure

  5. PROPAGATION OF AN INTER-FACIAL CRACK FRONT IN AN HETEROGENEOUS MEDIUM

    E-Print Network [OSTI]

    Schmittbuhl, Jean

    are described as an interface growth process. The dynamical exponent of a Family-Vicsek scaling is measured to the elastic coupling is small, the dynamics is controlled by in- dividual instabilities. On the contrary for strong elastic coupling, the dynamics is controlled by the whole front. Moreover during asperity de

  6. Sensitivity of mesoscale gravity waves to the baroclinicity of jet-front systems

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12T23:59:59.000Z

    To investigate the generation of mesoscale gravity waves from upper-tropospheric jet-front systems, five different life cycles of baroclinic waves are simulated with a high-resolution mesoscale model (MM5 with 10-km grid spacing). The baroclinicity...

  7. A front-tracking algorithm for accurate representation of surface tension

    E-Print Network [OSTI]

    Frey, Pascal

    A front-tracking algorithm for accurate representation of surface tension Stephane Popinet particularly, we focus our attention on obtaining an accurate description of the surface-tension terms and the associated pressure jump. We consider the stationary Laplace solution for a bub- ble with surface tension

  8. A discontinuous Galerkin front tracking method for two-phase flows with surface tension

    E-Print Network [OSTI]

    Peraire, Jaime

    A discontinuous Galerkin front tracking method for two-phase flows with surface tension Vinh with surface tension. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Interfaces separating regions tension. In this case, the interface separates two different fluids and the effect of surface tension re

  9. Development of Novel Front Contract Pastes for Crystalline Silicon Solar Cells

    SciTech Connect (OSTI)

    Duty, C.; Jellison, D. G.E. P.; Joshi, P.

    2012-04-05T23:59:59.000Z

    In order to improve the efficiencies of silicon solar cells, paste to silicon contact formation mechanisms must be more thoroughly understood as a function of paste chemistry, wafer properties and firing conditions. Ferro Corporation has been involved in paste development for over 30 years and has extensive expertise in glass and paste formulations. This project has focused on the characterization of the interface between the top contact material (silver paste) and the underlying silicon wafer. It is believed that the interface between the front contact silver and the silicon wafer plays a dominant role in the electrical performance of the solar cell. Development of an improved front contact microstructure depends on the paste chemistry, paste interaction with the SiNx, and silicon (“Si”) substrate, silicon sheet resistivity, and the firing profile. Typical front contact ink contains silver metal powders and flakes, glass powder and other inorganic additives suspended in an organic medium of resin and solvent. During fast firing cycles glass melts, wets, corrodes the SiNx layer, and then interacts with underlying Si. Glass chemistry is also a critical factor in the development of an optimum front contact microstructure. Over the course of this project, several fundamental characteristics of the Ag/Si interface were documented, including a higher-than-expected distribution of voids along the interface, which could significantly impact electrical conductivity. Several techniques were also investigated for the interfacial analysis, including STEM, EDS, FIB, EBSD, and ellipsometry.

  10. Light-Front Quantization and AdS/QCD: An Overview

    SciTech Connect (OSTI)

    de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC /Stanford U., Phys. Dept.

    2011-08-19T23:59:59.000Z

    We give an overview of the light-front holographic approach to strongly coupled QCD, whereby a confining gauge theory, quantized on the light front, is mapped to a higher-dimensional anti de Sitter (AdS) space. The framework is guided by the AdS/CFT correspondence incorporating a gravitational background asymptotic to AdS space which encodes the salient properties of QCD, such as the ultraviolet conformal limit at the AdS boundary at z {yields} 0, as well as modifications of the geometry in the large z infrared region to describe confinement and linear Regge behavior. There are two equivalent procedures for deriving the AdS/QCD equations of motion: one can start from the Hamiltonian equation of motion in physical space time by studying the off-shell dynamics of the bound state wavefunctions as a function of the invariant mass of the constituents. To a first semiclassical approximation, where quantum loops and quark masses are not included, this leads to a light-front Hamiltonian equation which describes the bound state dynamics of light hadrons in terms of an invariant impact variable {zeta} which measures the separation of the partons within the hadron at equal light-front time. Alternatively, one can start from the gravity side by studying the propagation of hadronic modes in a fixed effective gravitational background. Both approaches are equivalent in the semiclassical approximation. This allows us to identify the holographic variable z in AdS space with the impact variable {zeta}. Light-front holography thus allows a precise mapping of transition amplitudes from AdS to physical space-time. The internal structure of hadrons is explicitly introduced and the angular momentum of the constituents plays a key role.

  11. October 1999 1999, Elsevier Science Inc., 1040-6190/99/$see front matter PII S1040-6190(99)00074-3 77 Transmission Rights and

    E-Print Network [OSTI]

    Kammen, Daniel M.

    October 1999 © 1999, Elsevier Science Inc., 1040-6190/99/$­see front matter PII S1040., 1040-6190/99/$­see front matter PII S1040-6190(99)00074-3 The Electricity Journal Much

  12. 1359-6446/02/$ see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: DDT Vol. 7, No. 18 (Suppl.), 2002

    E-Print Network [OSTI]

    Sabatini, David M.

    1359-6446/02/$ ­ see front matter ©2002 Elsevier Science Ltd. All rights reserved. PII: DDT Vol. 7

  13. High-power, low-lateral divergence broad area quantum cascade lasers with a tilted front facet

    SciTech Connect (OSTI)

    Ahn, Sangil, E-mail: sangil.ahn@tuwien.ac.at; Schwarzer, Clemens; Zederbauer, Tobias; MacFarland, Donald C.; Detz, Hermann; Andrews, Aaron M.; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics, Vienna University of Technology, 1040 Vienna (Austria)

    2014-02-03T23:59:59.000Z

    We introduce a simple technique to improve the beam quality of broad area quantum cascade lasers. Moderately tilted front facets of the laser provide suppression of higher order lateral waveguide modes. A device with a width of 60??m and a front facet angle of 17° shows a nearly diffraction limited beam profile. In addition, the peak output power and the slope efficiency of the device are increased since most of the light inside the cavity is emitted through the tilted front facet by an asymmetric light intensity distribution along the cavity.

  14. FIELD TEST OF THE WATER-WHEEL IR (WIR) SPECTROMETER ON EVAPORATIVE SALT DEPOSITS AT TIBETAN PLATEAU. P. Sobron, J. J. Freeman, Alian Wang, Dept Earth and Planetary Sciences

    E-Print Network [OSTI]

    "contact survey", i.e., to install a WIR unit inside of a well set into the middle wheel of a pla- netary of WIR has a size of 10x7.5x6.5cm, mass of 450 grams, power consump- tion of 4W, and output data through transformed into a rugged, field portable NIR reflectance spectrometer that is able to operate in tough field

  15. Engineering Spectral Control Using Front Surface Filters for Maximum TPV Energy Conversion System Performance

    SciTech Connect (OSTI)

    TD Rahmlaw, Jr; JE Lazo-Wasem; EJ Gratrix; JJ Azarkevich; EJ Brown; DM DePoy; DR Eno; PM Fourspring; JR Parrington; RG Mahorter; B Wernsman

    2004-08-04T23:59:59.000Z

    Energy conversion efficiencies of better than 23% have been demonstrated for small scale tests of a few thermophotovoltaic (TPV) cells using front surface, tandem filters [1,2]. The engineering challenge is to build this level of efficiency into arrays of cells that provide useful levels of energy. Variations in cell and filter performance will degrade TPV array performance. Repeated fabrication runs of several filters each provide an initial quantification of the fabrication variation for front surface, tandem filters for TPV spectral control. For three performance statistics, within-run variation was measured to be 0.7-1.4 percent, and run-to-run variation was measured to be 0.5-3.2 percent. Fabrication runs using a mask have been shown to reduce variation across interference filters from as high 8-10 percent to less than 1.5 percent. Finally, several system design and assembly approaches are described to further reduce variation.

  16. Engineering Spectral Control Using Front Surface Filters for Maximum TPV Energy Conversion System Performance

    SciTech Connect (OSTI)

    T Rahmlow, Jr; J Lazo-Wasem, E Gratrix; J Azarkevich; E Brown; D DePoy; D Eno; P Fourspring; J Parrington; R Mahorter; B Wernsman

    2004-10-14T23:59:59.000Z

    Energy conversion efficiencies of better than 23% have been demonstrated for small scale tests of a few thermophotovoltaic (TPV) cells using front surface, tandem filters [1, 2]. The engineering challenge is to build this level of efficiency into arrays of cells that provide useful levels of energy. Variations in cell and filter performance will degrade TPV array performance. Repeated fabrication runs of several filters each provide an initial quantification of the fabrication variation for front surface, tandem filters for TPV spectral control. For three performance statistics, within-run variation was measured to be 0.7-1.4 percent, and run-to-run variation was measured to be 0.5-3.2 percent. Fabrication runs using a mask have been shown to reduce variation across interference filters from as high as 8-10 percent to less than 1.5 percent. Finally, several system design and assembly approaches are described to further reduce variation.

  17. Wave fronts, pulses and wave trains in photoexcited superlattices behaving as excitable or oscillatory media

    E-Print Network [OSTI]

    Arana, J I; Grahn, H T

    2011-01-01T23:59:59.000Z

    Undoped and strongly photoexcited semiconductor superlattices with field-dependent recombination behave as excitable or oscillatory media with spatially discrete nonlinear convection and diffusion. Infinitely long, dc-current-biased superlattices behaving as excitable media exhibit wave fronts with increasing or decreasing profiles, whose velocities can be calculated by means of asymptotic methods. These superlattices can also support pulses of the electric field. Pulses moving downstream with the flux of electrons can be constructed from their component wave fronts, whereas pulses advancing upstream do so slowly and experience saltatory motion: they change slowly in long intervals of time separated by fast transitions during which the pulses jump to the previous superlattice period. Photoexcited superlattices can also behave as oscillatory media and exhibit wave trains.

  18. Wave fronts, pulses and wave trains in photoexcited superlattices behaving as excitable or oscillatory media

    E-Print Network [OSTI]

    J. I. Arana; L. L. Bonilla; H. T. Grahn

    2011-09-30T23:59:59.000Z

    Undoped and strongly photoexcited semiconductor superlattices with field-dependent recombination behave as excitable or oscillatory media with spatially discrete nonlinear convection and diffusion. Infinitely long, dc-current-biased superlattices behaving as excitable media exhibit wave fronts with increasing or decreasing profiles, whose velocities can be calculated by means of asymptotic methods. These superlattices can also support pulses of the electric field. Pulses moving downstream with the flux of electrons can be constructed from their component wave fronts, whereas pulses advancing upstream do so slowly and experience saltatory motion: they change slowly in long intervals of time separated by fast transitions during which the pulses jump to the previous superlattice period. Photoexcited superlattices can also behave as oscillatory media and exhibit wave trains.

  19. Method of fabricating conductive electrodes on the front and backside of a thin film structure

    DOE Patents [OSTI]

    Tabada, Phillipe J. (Roseville, CA); Tabada, legal representative, Melody (Roseville, CA); Pannu, Satinderpall S. (Pleasanton, CA)

    2011-05-22T23:59:59.000Z

    A method of fabricating a thin film device having conductive front and backside electrodes or contacts. Top-side cavities are first formed on a first dielectric layer, followed by the deposition of a metal layer on the first dielectric layer to fill the cavities. Defined metal structures are etched from the metal layer to include the cavity-filled metal, followed by depositing a second dielectric layer over the metal structures. Additional levels of defined metal structures may be formed in a similar manner with vias connecting metal structures between levels. After a final dielectric layer is deposited, a top surface of a metal structure of an uppermost metal layer is exposed through the final dielectric layer to form a front-side electrode, and a bottom surface of a cavity-filled portion of a metal structure of a lowermost metal layer is also exposed through the first dielectric layer to form a back-side electrode.

  20. On relation between rest frame and light-front descriptions of quarkonium

    E-Print Network [OSTI]

    Kopeliovich, B Z; Schmidt, Ivan; Siddikov, M

    2015-01-01T23:59:59.000Z

    In this paper we study the relation between the light-front (infinite momentum) and rest-frame descriptions of quarkonia. While the former is more convenient for high-energy production, the latter is usually used for the evaluation of charmonium properties. In particular, we discuss the dynamics of a relativistically moving system with nonrelativistic internal motion and give relations between rest frame and light-front potentials used for the description of quarkonium states. We consider two approximations, first the small coupling regime, and next the nonperturbative small binding energy approximation. In both cases we get consistent results. Our results could be relevant for the description of final state interactions in a wide class of processes, including quarkonium production on nuclei and plasma. Moreover, they can be extended to the description of final state interactions in the production of weakly bound systems, such as for example the deuteron.

  1. On relation between rest frame and light-front descriptions of quarkonium

    E-Print Network [OSTI]

    B. Z. Kopeliovich; E. Levin; Ivan Schmidt; M. Siddikov

    2015-01-07T23:59:59.000Z

    In this paper we study the relation between the light-front (infinite momentum) and rest-frame descriptions of quarkonia. While the former is more convenient for high-energy production, the latter is usually used for the evaluation of charmonium properties. In particular, we discuss the dynamics of a relativistically moving system with nonrelativistic internal motion and give relations between rest frame and light-front potentials used for the description of quarkonium states. We consider two approximations, first the small coupling regime, and next the nonperturbative small binding energy approximation. In both cases we get consistent results. Our results could be relevant for the description of final state interactions in a wide class of processes, including quarkonium production on nuclei and plasma. Moreover, they can be extended to the description of final state interactions in the production of weakly bound systems, such as for example the deuteron.

  2. Light-Front Holography and Gauge/Gravity Duality: The Light Meson and Baryon Spectra

    SciTech Connect (OSTI)

    de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC

    2009-12-09T23:59:59.000Z

    Starting from the bound state Hamiltonian equation of motion in QCD, we derive relativistic light-front wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. These equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti-de Sitter (AdS) space. Its eigenvalues give the hadronic spectrum, and its eigenmodes represent the probability amplitudes of the hadronic constituents at a given scale. An effective classical gravity description in a positive-sign dilaton background exp(+{kappa}{sup 2}z{sup 2}) is given for the phenomenologically successful soft-wall model which naturally encodes the internal structure of hadrons and their orbital angular momentum. Applications to the light meson and baryon spectrum are presented.

  3. report 2013 Front cover image: Greenough River Solar Farm, Western Australia.

    E-Print Network [OSTI]

    Green, Donna

    R heAtinG 59 WinD PoWeR 65 appendiCes 65 APPenDiX 1: toP 10 SolAR PoStCoDeS by StAte 68 APPenDiX 2 #12. From jobs and investment in regional areas to solar panels, solar hot water and high efficiencyClean energy australia report 2013 #12;Front cover image: Greenough River Solar Farm, Western

  4. AdS/QCD, LIight-Front Holography, and the Non-perturbative Running Coupling

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC; de Teramond, Guy; /Costa Rica U.; Deur, Alexandre; /Jefferson Lab

    2010-04-29T23:59:59.000Z

    The combination of Anti-de Sitter space (AdS) methods with light-front (LF) holography provides a remarkably accurate first approximation for the spectra and wavefunctions of meson and baryon light-quark bound states. The resulting bound-state Hamiltonian equation of motion in QCD leads to relativistic light-front wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. These equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti-de Sitter (AdS) space. The eigenvalues give the hadronic spectrum, and the eigenmodes represent the probability distributions of the hadronic constituents at a given scale. A positive-sign confining dilaton background modifying AdS space gives a very good account of meson and baryon spectroscopy and form factors. The light-front holographic mapping of this model also leads to a non-perturbative effective coupling {alpha}{sub s}{sup Ads} (Q{sup 2}) which agrees with the effective charge defined by the Bjorken sum rule and lattice simulations. It displays a transition from perturbative to nonperturbative conformal regimes at a momentum scale {approx} 1 GeV. The resulting {beta}-function appears to capture the essential characteristics of the full {beta}-function of QCD, thus giving further support to the application of the gauge/gravity duality to the confining dynamics of strongly coupled QCD.

  5. AdS/CFT and Light-Front Holography: A Theory of Strong Interactions

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC; Teramond, Guy F.de; /Costa Rica U.

    2009-02-23T23:59:59.000Z

    Recent developments in the theory of strong interactions are discussed in the framework of the AdS/CFT duality between string theories of gravity in a higher dimension Anti-de Sitter space and conformal quantum field theories in physical space-time. This novel theoretical approach, combined with 'light-front holography', leads to new insights into the quark and gluon structure of hadrons and a viable first approximation to quantum chromodynamics, the fundamental theory of the strong and nuclear interactions.

  6. Method and apparatus for generating radiation utilizing DC to AC conversion with a conductive front

    DOE Patents [OSTI]

    Dawson, J.M.; Mori, W.B.; Lai, C.H.; Katsouleas, T.C.

    1998-07-14T23:59:59.000Z

    Method and apparatus ar disclosed for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing. 4 figs.

  7. Method and apparatus for generating radiation utilizing DC to AC conversion with a conductive front

    DOE Patents [OSTI]

    Dawson, John M. (Pacific Palisades, CA); Mori, Warren B. (Hermosa Beach, CA); Lai, Chih-Hsiang (So. Pasadena, CA); Katsouleas, Thomas C. (Malibu, CA)

    1998-01-01T23:59:59.000Z

    Method and apparatus for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing.

  8. Svendborg Brakes | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDITCalifornia Sector:Shrenik IndustriesState of

  9. H-Morph: An indirect approach to advancing front hex meshing

    SciTech Connect (OSTI)

    OWEN,STEVEN J.; SAIGAL,SUNIL

    2000-05-30T23:59:59.000Z

    H-Morph is a new automatic algorithm for the generation of a hexahedral-dominant finite element mesh for arbitrary volumes. The H-Morph method starts with an initial tetrahedral mesh and systematically transforms and combines tetrahedral into hexahedra. It uses an advancing front technique where the initial front consists of a set of prescribed quadrilateral surface facets. Fronts are individually processed by recovering each of the six quadrilateral faces of a hexahedron from the tetrahedral mesh. Recovery techniques similar to those used in boundary constrained Delaunay mesh generation are used. Tetrahedral internal to the six hexahedral faces are then removed and a hexahedron is formed. At any time during the H-Morph procedure a valid mixed hexahedral-tetrahedral mesh is in existence within the volume. The procedure continues until no tetrahedral remain within the volume, or tetrahedral remain which cannot be transformed or combined into valid hexahedral elements. Any remaining tetrahedral are typically towards the interior of the volume, generally a less critical region for analysis. Transition from tetrahedral to hexahedra in the final mesh is accomplished through pyramid shaped elements. Advantages of the proposed method include its ability to conform to an existing quadrilateral surface mesh, its ability to mesh without the need to decompose or recognize special classes of geometry, and its characteristic well-aligned layers of elements parallel to the boundary. Example test cases are presented on a variety of models.

  10. Delayed muons in extensive air showers and double-front showers

    SciTech Connect (OSTI)

    Beisembaev, R. U.; Vavilov, Yu. N., E-mail: yuvavil@mail.ru; Vildanov, N. G.; Kruglov, A. V.; Stepanov, A. V. [Russian Academy of Sciences, Lebedev Institute of Physics (Russian Federation); Takibaev, J. S. [Al-Farabi Kazakh National University (Kazakhstan)

    2009-11-15T23:59:59.000Z

    The results of a long-term experiment performed in the period between 1995 and 2006 with the aid of the MUON-T underground (20 mwe) scintillation facility arranged at the Tien Shan mountain research station at an altitude of 3340 m above sea level are presented. The time distribution of delayed muons with an energy in excess of 5 GeV in extensive air showers of energy not lower than 106 GeV with respect to the shower front was obtained with a high statistical significance in the delay interval between 30 and 150 ns. An effect of the geomagnetic field in detecting delayed muons in extensive air showers was discovered. This effect leads to the asymmetry of their appearance with respect to the north-south direction. The connection between delayed muons and extensive air showers featuring two fronts separated by a time interval of several tens of to two hundred nanoseconds is discussed. This connection gives sufficient grounds to assume that delayed muons originate from the decays of pions and kaons produced in the second, delayed, front of extensive air showers.

  11. FBI Fingerprint Image Capture System High-Speed-Front-End throughput modeling

    SciTech Connect (OSTI)

    Rathke, P.M.

    1993-09-01T23:59:59.000Z

    The Federal Bureau of Investigation (FBI) has undertaken a major modernization effort called the Integrated Automated Fingerprint Identification System (IAFISS). This system will provide centralized identification services using automated fingerprint, subject descriptor, mugshot, and document processing. A high-speed Fingerprint Image Capture System (FICS) is under development as part of the IAFIS program. The FICS will capture digital and microfilm images of FBI fingerprint cards for input into a central database. One FICS design supports two front-end scanning subsystems, known as the High-Speed-Front-End (HSFE) and Low-Speed-Front-End, to supply image data to a common data processing subsystem. The production rate of the HSFE is critical to meeting the FBI`s fingerprint card processing schedule. A model of the HSFE has been developed to help identify the issues driving the production rate, assist in the development of component specifications, and guide the evolution of an operations plan. A description of the model development is given, the assumptions are presented, and some HSFE throughput analysis is performed.

  12. Resource intensities of the front end of the nuclear fuel cycle

    SciTech Connect (OSTI)

    Schneider, E.; Phathanapirom, U. [The University of Texas at Austin, 1 University Station C2200, Austin TX 78712 (United States); Eggert, R.; Collins, J. [Colorado School of Mines, 1500 Illinois St., Golden CO 80401 (United States)

    2013-07-01T23:59:59.000Z

    This paper presents resource intensities, including direct and embodied energy consumption, land and water use, associated with the processes comprising the front end of the nuclear fuel cycle. These processes include uranium extraction, conversion, enrichment, fuel fabrication and depleted uranium de-conversion. To the extent feasible, these impacts are calculated based on data reported by operating facilities, with preference given to more recent data based on current technologies and regulations. All impacts are normalized per GWh of electricity produced. Uranium extraction is seen to be the most resource intensive front end process. Combined, the energy consumed by all front end processes is equal to less than 1% of the electricity produced by the uranium in a nuclear reactor. Land transformation and water withdrawals are calculated at 8.07 m{sup 2} /GWh(e) and 1.37x10{sup 5} l/GWh(e), respectively. Both are dominated by the requirements of uranium extraction, which accounts for over 70% of land use and nearly 90% of water use.

  13. FPI (Islamic Defenders' Front): the Making of a Violent Islamist Movement in the New Democracy of Indonesia

    E-Print Network [OSTI]

    Munajat

    2012-07-16T23:59:59.000Z

    The current study is aimed at investigating the puzzle of why FPI (Islamic Defenders' Front) has chosen to adopt violent strategies within the democratic context of Indonesia. Much of literature on social movements suggests that democracy...

  14. Recursion relations for multi-gluon off-shell amplitudes on the light-front and Wilson lines

    E-Print Network [OSTI]

    C. Cruz-Santiago; P. Kotko; A. Stasto

    2015-03-06T23:59:59.000Z

    We analyze the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that the previously derived recursion relation between tree level off-shell amplitudes in this formalism actually resums whole classes of graphs into a Wilson line. More precisely, we establish a correspondence between the light-front methods for the computation of the off-shell amplitudes and the approach which makes use of the matrix elements of straight infinite Wilson lines, which are manifestly gauge invariant objects. Furthermore, since it is needed to explicitly verify the gauge invariance of light-front amplitudes, it is demonstrated that the Ward identities in this framework need additional instantaneous terms in the light-front graphs.

  15. Recursion relations for multi-gluon off-shell amplitudes on the light-front and Wilson lines

    E-Print Network [OSTI]

    Cruz-Santiago, C; Stasto, A

    2015-01-01T23:59:59.000Z

    We analyze the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that the previously derived recursion relation between tree level off-shell amplitudes in this formalism actually resums whole classes of graphs into a Wilson line. More precisely, we establish a correspondence between the light-front methods for the computation of the off-shell amplitudes and the approach which makes use of the matrix elements of straight infinite Wilson lines, which are manifestly gauge invariant objects. Furthermore, since it is needed to explicitly verify the gauge invariance of light-front amplitudes, it is demonstrated that the Ward identities in this framework need additional instantaneous terms in the light-front graphs.

  16. Broadband RF Front-End Design for Multi-Standard Receiver with High-Linearity and Low-Noise Techniques

    E-Print Network [OSTI]

    Kim, Ju Sung

    2012-02-14T23:59:59.000Z

    Future wireless communication devices must support multiple standards and features on a single-chip. The trend towards software-defined radio requires flexible and efficient RF building blocks which justifies the adoption of broadband receiver front...

  17. Wilson Bull., 110(3), 1998, pp. 352-361 VOCALIZATIONS OF THE BLUE-FRONTED AMAZON

    E-Print Network [OSTI]

    Fernández-Juricic, Esteban

    of increasing interactions between individuals. The frequency containing the greatest amount of energy-fronted Amazon (Amazona aes- tiva) is a parrot whose distribution extends over northeastern Brazil, Bolivia

  18. Complex Embedded Automotive Control Systems DaimlerChrysler

    E-Print Network [OSTI]

    Duffy, Ken

    progressed along several lines of inquiry, it appears to be the case that almost no effort has been devoted equipped with active systems (4-wheel- steering, active suspension, active brakes, etc.) may, in principle and rear steer-by-wire, brake-by-wire and active suspensions. An integrated chassis controller would com

  19. The Central American cold surge: an observational analysis of the deep southward penetration of North American cold fronts

    E-Print Network [OSTI]

    Reding, Philip John

    1992-01-01T23:59:59.000Z

    THE CENTRAL AMERICAN COLD SURGE: AN OBSERVATIONAL ANALYSIS OF THE DEEP SOUTHWARD PENETRATION OF NORTH AMERICAN COLD FRONTS A Thesis by PHILIP JOHN REDING Submitted to the Office of Graduate Studies of Texas A &M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Meteorology THE CENTRAL AMERICAN COLD SURGE: AN OBSERVATIONAL ANALYSIS OF THE DEEP SOUTHWARD PENETRATION OF NORTH AMERICAN COLD FRONTS A Thesis by PHILIP...

  20. front cover

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, , ., December 8,JohnResolving Modeling9 OnPower

  1. front cover

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, , ., December 8,JohnResolving Modeling9

  2. front cover

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, , ., December 8,JohnResolving Modeling9Preferred

  3. Front cover

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613 122 40CoalLease(Billion2,12803 Table A1.GasYear Jan FebCubic(Million CubicINVESTMENT IN

  4. Section: Front

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz is Taking OverEvaluating ' M M t .9Target-atomP.

  5. Front-End Board with Cyclone V as a Test High-Resolution Platform for the Auger-Beyond-2015 Front End Electronics

    E-Print Network [OSTI]

    Zbigniew Szadkowski

    2014-06-07T23:59:59.000Z

    The surface detector (SD) array of the Pierre Auger Observatory containing at present 1680 water Cherenkov detectors spread over an area of 3000 km^2 started to operate since 2004. The currently used Front-End Boards are equipped with no-more produced ACEX and obsolete Cyclone FPGA (40 MSps/15-bit of dynamic range). Huge progress in electronics and new challenges from physics impose a significant upgrade of the SD electronics either to improve a quality of measurements (much higher sampling and much wider dynamic range) or pick-up from a background extremely rare events (new FPGA algorithms based on sophisticated approaches like e.g. spectral triggers or neural networks). Much higher SD sensitivity is necessary to confirm or reject hypotheses critical for a modern astrophysics. The paper presents the Front-End Board (FEB) with the biggest Cyclone V E FPGA 5CEFA9F31I7N, supporting 8 channels sampled with max. 250 MSps @ 14-bit resolution. Considered sampling for the SD is 120 MSps, however, the FEB has been developed with external anti-aliasing filters to keep a maximal flexibility. Six channels are targeted to the SD, two the rest for other experiments like: Auger Engineering Radio Array and additional muon counters. The FEB is an intermediate design pluged-in the actually used Unified Board communicating with micro-controller at 40 MHz, however providing even 250 MSPs sampling with 20-bit dynamic range, equipped in a virtual NIOS processor and supporting 256 MB of SDRAM as well as with an implemented spectral trigger based on the Discrete Cosine Transform for a detection of very inclined "old" showers. The FEB can also support a neural network developing for a detection of "young" showers, potentially generated by neutrinos.

  6. Influence of physical parameters and operating conditions for structural integrity of mechanical system subjected to squeal noise

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for the static load and circular wave front lines for the ramp loading. Introduction Disc brake systems-linear vibrations, acoustic radiation, brake squeal, friction Abstract. This work proposes to study the effects of physical parameters and loading conditions on both dynamic and acoustic responses of a brake system

  7. A Vehicle-to-Vehicle Communication Protocol for Cooperative Collision Warning

    E-Print Network [OSTI]

    Liu, Jie

    safer than B due to the following two reasons: ¤ Line-of-sight limitation of brake light: Typically by Vodafone-U.S. Foundation Graduate Fellowship. and £ , travel in the same lane. When ¡ suddenly brakes, a driver can only see the brake light from the vehicle di- rectly in front1 . Thus, very likely vehicle

  8. Quantum feedback cooling of a single trapped ion in front of a mirror

    E-Print Network [OSTI]

    V. Steixner; P. Rabl; P. Zoller

    2005-06-22T23:59:59.000Z

    We develop a theory of quantum feedback cooling of a single ion trapped in front of a mirror. By monitoring the motional sidebands of the light emitted into the mirror mode we infer the position of the ion, and act back with an appropriate force to cool the ion. We derive a feedback master equation along the lines of the quantum feedback theory developed by Wiseman and Milburn, which provides us with cooling times and final temperatures as a function of feedback gain and various system parameters.

  9. A dynamical model for longitudinal wave functions in light-front holographic QCD

    E-Print Network [OSTI]

    S. S. Chabysheva; J. R. Hiller

    2013-07-14T23:59:59.000Z

    We construct a Schrodinger-like equation for the longitudinal wave function of a meson in the valence qq-bar sector, based on the 't Hooft model for large-N two-dimensional QCD, and combine this with the usual transverse equation from light-front holographic QCD, to obtain a model for mesons with massive quarks. The computed wave functions are compared with the wave function ansatz of Brodsky and De Teramond and used to compute decay constants and parton distribution functions. The basis functions used to solve the longitudinal equation may be useful for more general calculations of meson states in QCD.

  10. Performance of the Fully Digital FPGA-based Front-End Electronics for the GALILEO Array

    E-Print Network [OSTI]

    D. Barrientos; M. Bellato; D. Bazzacco; D. Bortolato; P. Cocconi; A. Gadea; V. González; M. Gulmini; R. Isocrate; D. Mengoni; A. Pullia; F. Recchia; D. Rosso; E. Sanchis; N. Toniolo; C. A. Ur; J. J. Valiente-Dobón

    2014-06-16T23:59:59.000Z

    In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53 per mil at an energy of 1.33 MeV.

  11. Transient nature of salt movement with wetting front in an unsaturated soil

    E-Print Network [OSTI]

    Soman, Vishwas Vinayak

    1992-01-01T23:59:59.000Z

    from unit area of soil (me/sq. m), () is moisture content of the soil layer at time of extraction for salt (cc/cc), Co is initial average salt concentration in the soil solution at moisture content 8 (me/liter) and C1 is average concentration...TRANSIENT NATURE OF SALT MOVEMENT WITH WETTING FRONT IN AN UNSATURATED SOIL A Thesis bY VISHWAS VINAYAK SOMAN Submitted to the Office of Graduate Studies of Texas A&M UniversitY in partial fulfillment of the requirements for the degree...

  12. On the ion front of a plasma expanding into a vacuum

    SciTech Connect (OSTI)

    Allen, J. E. [OCIAM, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom) [OCIAM, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); University College, Oxford, Oxford OX1 4BH (United Kingdom); Perego, M. [Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306 (United States)] [Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306 (United States)

    2014-03-15T23:59:59.000Z

    Calculations are reported on the expansion of a plasma into a vacuum, using a model of cold ions and Boltzmann electrons. The initial distribution of the ions at the edge of the plasma greatly affects the subsequent expansion. An initial abrupt drop of ion density leads to an expansion in which the abrupt drop is maintained. A finite slope, however, leads to the formation of a peak of ion density at the ion front. The subsequent behaviour may lead to wave breaking and the formation of multi-valued ion velocity distributions.

  13. Meso and microscale features of the lower portion of cold fronts

    E-Print Network [OSTI]

    Beniura, Hideo

    1962-01-01T23:59:59.000Z

    of the friction head on density surges in stratified fluids (Schmidt, 1910; Prandtl, 1952; Ippen and Harleman, 1952) by means of modified Froude numbers. Figure 3, after PrandtL shows an idealized picture of an undercutting flow of cold air with a dip behind... the friction head. The dashed lines represent the flow relative to the ground. It will be noted that a nose exists on the surge front such as described previously. Berson's observations were inadequate to prove or disprove the occurrence of the overhanging...

  14. Superconducting magnets for SCRF cryomodules at front end of linear accelerators

    SciTech Connect (OSTI)

    Kashikhin, V.S.; Andreev, N.; Orlov, Y.; Orris, D.F.; Tartaglia, M.A.; /Fermilab

    2010-05-01T23:59:59.000Z

    Linear accelerators based on a superconducting technology need various superconducting magnets mounted inside SCRF Cryomodules. Relatively weak iron-dominated magnets are installed at the front end of linear accelerators. The focusing quadrupoles have integrated gradients in the range of 1-4 T, and apertures in the range 35-90 mm. Superconducting dipole correctors and quadrupoles were designed at Fermilab for various projects. In this paper these magnet designs, and test results of a fabricated dipole corrector, are presented. Also briefly discussed are magnetic and mechanical designs, quench protection, cooling, fabrication, and assembly into cryomodule.

  15. Dynamical Expansion of Ionization and Dissociation Front around a Massive Star. I. A Mode of Triggered Star Formation

    E-Print Network [OSTI]

    Takashi Hosokawa; Shu-ichiro Inutsuka

    2005-01-08T23:59:59.000Z

    We analyze the dynamical expansion of the HII region and outer photodissociation region (PDR) around a massive star by solving the UV and FUV radiation transfer and the thermal and chemical processes in a time-dependent hydrodynamics code. We focus on the physical structure of the shell swept up by the shock front (SF) preceding the ionization front (IF). After the IF reaches the initial Stromgren radius, the SF emerges in front of the IF and the geometrically thin shell bounded with the IF and the SF is formed. The gas density inside the shell is about 10-100 times as high as the ambient gas density. Initially the dissociation fronts expands faster than IF and the PDR is formed outside the HII region. Thereafter the IF and SF gradually overtakes the proceeding dissociation fronts (DFs), and eventually DFs are taken in the shell. The chemical composition within the shell is initially atomic, but hydrogen and carbon monoxide molecules are gradually formed. This is partly because the IF and SF overtake DFs and SF enters the molecular region, and partly because the reformation timescales of the molecules become shorter than the dynamical timescale. The gas shell becomes dominated by the molecular gas by the time of gravitational fragmentation, which agrees with some recent observations. A simple estimation of star formation rate in the shell can provide a significant star formation rate in our galaxy.

  16. Novel Approach for Selective Emitter Formation and Front Side Metallization of Crystalline Silicon Solar Cells

    SciTech Connect (OSTI)

    Baomin Xu

    2010-07-28T23:59:59.000Z

    In this project we will explore the possibility of forming the front side metallization and selective emitter layer for the crystalline silicon solar cells through using selective laser ablation to create contact openings on the front surface and a screen printer to make connections with conductive paste. Using this novel approach we expect to reduce the specific contact resistance of the silver gridlines by about one order of magnitude compared to the state-of-art industrial crystalline silicon solar cells to below 1 m??cm2, and use lightly doped n+ emitter layer with sheet resistance of not smaller than 100 ?/?. This represents an enabling improvement on crystalline silicon solar cell performance and can increase the absolute efficiency of the solar cell by about 1%. In this scientific report we first present our result on the selective laser ablation of the nitride layer to make contact openings. Then we report our work on the solar cell fabrication by using the laser ablated contact openings with self-doping paste. Through various electrical property characterization and SIMS analysis, the factors limiting the cell performance have been discussed. While through this proof-of-concept project we could not reach the target on cell efficiency improvement, the process to fabricate 125mm full-sized silicon solar cells using laser ablation and self-doping paste has been developed, and a much better understanding of technical challenges has been achieved. Future direction to realize the potential of the new technology has been clearly defined.

  17. Status and specifications of a Project X front-end accelerator test facility at Fermilab

    SciTech Connect (OSTI)

    Steimel, J.; Webber, R.; Madrak, R.; Wildman, D.; Pasquinelli, R.; Evans-Peoples, E.; /Fermilab

    2011-03-01T23:59:59.000Z

    This paper describes the construction and operational status of an accelerator test facility for Project X. The purpose of this facility is for Project X component development activities that benefit from beam tests and any development activities that require 325 MHz or 650 MHz RF power. It presently includes an H- beam line, a 325 MHz superconducting cavity test facility, a 325 MHz (pulsed) RF power source, and a 650 MHz (CW) RF power source. The paper also discusses some specific Project X components that will be tested in the facility. Fermilab's future involves new facilities to advance the intensity frontier. In the early 2000's, the vision was a pulsed, superconducting, 8 GeV linac capable of injecting directly into the Fermilab Main Injector. Prototyping the front-end of such a machine started in 2005 under a program named the High Intensity Neutrino Source (HINS). While the HINS test facility was being constructed, the concept of a new, more versatile accelerator for the intensity frontier, now called Project X, was forming. This accelerator comprises a 3 GeV CW superconducting linac with an associated experimental program, followed by a pulsed 8 GeV superconducting linac to feed the Main Injector synchrotron. The CW Project X design is now the model for Fermilab's future intensity frontier program. Although CW operation is incompatible with the original HINS front-end design, the installation remains useful for development and testing many Project X components.

  18. Uranium and its relationship to host rock mineralogy in an unoxidized roll front in the Jackson group, South Texas

    E-Print Network [OSTI]

    Prasse, Eric Martin

    1978-01-01T23:59:59.000Z

    of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject: Geology URANIUM AND ITS RELATIONSHIP TO HOST ROCK MINERALOGY IN AN UNOXIDIZED ROLL FRONT IN THE JACKSON GROUP, SOUTH TEXAS A Thesis by ERIC MARTIN PRASSE Approved as to style... and content by: Chairman of Committee r Head of Department Member Member December 1978 :& ~'8% 055 ABSTRACT Uranium and its Relat1onship to Host Rock Mineralogy in an Unox1dized Roll Front in the Jackson Group, South Texas (December, 1978) Eric...

  19. Scour of simulated Gulf Coast sand beaches due to wave action in front of sea walls and dune barriers

    E-Print Network [OSTI]

    Chesnutt, Charles Burgess

    1971-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE May 1971 Ma)or Sub)ect: Civil Engineering SCOUR OF SIM(JLATED GULF COAST SAND BEACHES DUE TO WAVE ACTION IN FRONT OF SEA WALLS AND DUNE BARRIERS Q m Q F z A Thesis z m Q C by CHARLES BURGESS CHESNUTT L' m ) m... angle 53 LIST OF FIGURES (CONTINUED) Figure Page 15 Scour depth at the sea wall versus beach slope for constant wave steepness and varying sea wall angle 54 INTRODUCTION The problem of scour in front of sea walls has plagued coastal engineers...

  20. Generalizing the flash technique in the front-face configuration to measure the thermal diffusivity of semitransparent solids

    SciTech Connect (OSTI)

    Pech-May, Nelson Wilbur [Departamento de Física Aplicada I, Escuela Técnica Superior de Ingeniería, Universidad del País Vasco UPV/EHU, Alameda Urquijo s/n, 48013 Bilbao (Spain); Department of Applied Physics, CINVESTAV Unidad Mérida, carretera Antigua a Progreso km6, A.P. 73 Cordemex, Mérida Yucatán 97310, México (Mexico); Mendioroz, Arantza; Salazar, Agustín, E-mail: agustin.salazar@ehu.es [Departamento de Física Aplicada I, Escuela Técnica Superior de Ingeniería, Universidad del País Vasco UPV/EHU, Alameda Urquijo s/n, 48013 Bilbao (Spain)

    2014-10-15T23:59:59.000Z

    In this work, we have extended the front-face flash method to retrieve simultaneously the thermal diffusivity and the optical absorption coefficient of semitransparent plates. A complete theoretical model that allows calculating the front surface temperature rise of the sample has been developed. It takes into consideration additional effects, such as multiple reflections of the heating light beam inside the sample, heat losses by convection and radiation, transparency of the sample to infrared wavelengths, and heating pulse duration. Measurements performed on calibrated solids, covering a wide range of absorption coefficients (from transparent to opaque) and thermal diffusivities, validate the proposed method.

  1. Design and construction of the front-end electronics data acquisition for the SLD CRID

    SciTech Connect (OSTI)

    Hoeflich, J.; McShurley, D.; Marshall, D.; Oxoby, G.; Shapiro, S.; Stiles, P. (Stanford Linear Accelerator Center, Menlo Park, CA (United States)); Spencer, E. (California Univ., Santa Cruz, CA (United States). Inst. for Particle Physics)

    1991-04-01T23:59:59.000Z

    This paper describes the front-end electronics for the Cherenkov Ring Imaging Detector (CRID) of the SLD at the Stanford Linear Accelerator Center. The design philosophy and implementation are discussed with emphasis on the low-noise hybrid amplifiers, signal processing and data acquisition electronics. The system receives signals from a highly efficient single-photo electron detector. These signals are shaped and amplified before being stored in an analog memory and processed by a digitizing system. The data from several ADCs are multiplexed and transmitted via fiber optics to the SLD FASTBUS system. The authors highlight the technologies used, as well as the space, power dissipation, and environmental constraints imposed on the system.

  2. Evaluation of a front-end ASIC for the readout of PMTs in large dynamic range

    E-Print Network [OSTI]

    Wu, Weihao; Liang, Yu; Yu, Li; Liu, Jianfeng; Liu, Shubin; An, Qi

    2015-01-01T23:59:59.000Z

    The Large High Altitude Air Shower Observatory (LHAASO) project has been proposed for the survey and study of cosmic rays. In the LHAASO project, the Water Cherenkov Detector Array (WCDA) is one of major detectors for searching gamma ray sources. A Charge-to-Time Convertor (QTC) ASIC (Application Specification Integrated Circuit) fabricated in Global Foundry 0.35 {\\mu}m CMOS technology, has been developed for readout of Photomultiplier Tubes (PMTs) in the WCDA. This paper focuses on the evaluation of this front-end readout ASIC performance. Test results indicate that the time resolution is better than 400 ps and the charge resolution is better than 1% with large input signals and remains better than 15% @ 1 Photo Electron (P.E.), both beyond the application requirement. Moreover, this ASIC has a weak ambient temperature dependence, low input rate dependence and high channel-to-channel isolation.

  3. Evaluation of a front-end ASIC for the readout of PMTs in large dynamic range

    E-Print Network [OSTI]

    Weihao Wu; Lei Zhao; Yu Liang; Li Yu; Jianfeng Liu; Shubin Liu; Qi An

    2015-02-05T23:59:59.000Z

    The Large High Altitude Air Shower Observatory (LHAASO) project has been proposed for the survey and study of cosmic rays. In the LHAASO project, the Water Cherenkov Detector Array (WCDA) is one of major detectors for searching gamma ray sources. A Charge-to-Time Convertor (QTC) ASIC (Application Specification Integrated Circuit) fabricated in Global Foundry 0.35 {\\mu}m CMOS technology, has been developed for readout of Photomultiplier Tubes (PMTs) in the WCDA. This paper focuses on the evaluation of this front-end readout ASIC performance. Test results indicate that the time resolution is better than 400 ps and the charge resolution is better than 1% with large input signals and remains better than 15% @ 1 Photo Electron (P.E.), both beyond the application requirement. Moreover, this ASIC has a weak ambient temperature dependence, low input rate dependence and high channel-to-channel isolation.

  4. Local stress-induced effects on AlGaAs/AlOx oxidation front shape

    SciTech Connect (OSTI)

    Chouchane, F.; Almuneau, G., E-mail: almuneau@laas.fr; Arnoult, A.; Lacoste, G.; Fontaine, C. [CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse (France); Univ de Toulouse, UPS, LAAS, F-31400 Toulouse (France); Cherkashin, N. [Univ de Toulouse, UPS, LAAS, F-31400 Toulouse (France); CNRS, CEMES, 29 Rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France)

    2014-07-28T23:59:59.000Z

    The lateral oxidation of thick AlGaAs layers (>500?nm) is studied. An uncommon shape of the oxide tip is evidenced and attributed to the embedded stress distribution, inherent to the oxidation reaction. Experimental and numerical studies of the internal strain in oxidized Al{sub x}Ga{sub 1?x}As/GaAs structures were carried out by dark-field electron holography and finite element methods. A mapping of the strain distribution around the AlGaAs/oxide interface demonstrates the main role of internal stress on the shaping of the oxide front. These results demonstrate the high relevance of strain in oxide-confined III-V devices, in particular, with over-500-nm thick AlOx confinement layers.

  5. The Analog Front-end Prototype Electronics Designed for LHAASO WCDA

    E-Print Network [OSTI]

    Ma, Cong; Guo, Yu-Xiang; Liu, Jian-Feng; Liu, Shu-Bin; An, Qi

    2015-01-01T23:59:59.000Z

    In the readout electronics of the Water Cerenkov Detector Array (WCDA) in the Large High Altitude Air Shower Observatory (LHAASO) experiment, both high-resolution charge and time measurement are required over a dynamic range from 1 photoelectron (P.E.) to 4000 P.E. The Analog Front-end (AFE) circuit is one of the crucial parts in the whole readout electronics. We designed and optimized a prototype of the AFE through parameter calculation and circuit simulation, and conducted initial electronics tests on this prototype to evaluate its performance. Test results indicate that the charge resolution is better than 1% @ 4000 P.E. and remains better than 10% @ 1 P.E., and the time resolution is better than 0.5 ns RMS, which is better than application requirement.

  6. Development of front-end readout electronics for silicon strip detectors

    E-Print Network [OSTI]

    Yi Qian; Hong Su; Jie Kong; Cheng-Fu Dong; Xiao-Li Ma; Xiao-Gang Li

    2011-06-10T23:59:59.000Z

    A front-end readout electronics system has been developed for silicon strip detectors. The system uses an application specific integrated circuit (ASIC) ATHED to realize multi-channel E&T measurement. The slow control of ASIC chips is achieved by parallel port and the timing control signals of ASIC chips are provided by the CPLD. The data acquisition is implemented with a PXI-DAQ card. The system software has a user-friendly GUI which uses LabWindows/CVI in Windows XP operating system. Test results showed that the energy resolution is about 1.22 % for alphas at 5.48 MeV and the maximum channel crosstalk of system is 4.6%. The performance of the system is very reliable and suitable for nuclear physics experiments.

  7. PDP-11 front-end for a VAX-11/780

    SciTech Connect (OSTI)

    Browne, M.J.; Granieri, C.; Sherden, D.J.; Weaver, L.J.

    1980-01-01T23:59:59.000Z

    An unpublicized feature of the VAX-11/780 is the provision for attaching a PDP-11 to the VAX UNIBUS Adapter. Doing this can give significantly improved I/O performance for applications which are limited by overhead in the VAX I/O driver rather than by the transfer speed of the UNIBUS itself. Such a system was implemented by using a PDP-11/04 as a front-end to a CAMAC data acquisition system. Both the PDP and the VAX have full access to the UNIBUS. That portion of the PDP address space that does not have UNIBUS memory can be mapped to buffers in the VAX memory; this approach allows the PDP to access VAX memory and to initiate DMA transfers directly to the VAX. The VAX also has full access to the PDP memory; a convenient means for developing and downloading the PDP software is thus provided. 5 figures.

  8. Review of input stages used in front end electronics for particle detectors

    E-Print Network [OSTI]

    Kaplon, J

    2015-01-01T23:59:59.000Z

    In this paper we present noise analysis of the input stages most commonly used in front end electronics for particle detectors. Analysis shows the calculation of the input referenced noise related to the active devices. It identifies the type, parallel or series, of the equivalent noise sources related to the input transistors, which is the important input for the further choice of the signal processing method. Moreover we calculate the input impedance of amplifiers employed in applications where the particle detector is connected to readout electronics by means of transmission line. We present schematics, small signal models,a complete set of equations, and results of the major steps of calculations for all discussed circuits.

  9. An electron front end for the Fermilab multi-species 8 GeV SCRF linac

    SciTech Connect (OSTI)

    Philippe R.-G. Piot; G W Foster

    2004-07-08T23:59:59.000Z

    Fermilab is considering a 8 GeV superconducting linac whose primary mission is to serve as an intense H{sup -} injector for the main injector. This accelerator is also planned to be used for accelerating various other species (e.g. electrons, protons and muons). In the present paper we investigate the possibility of such a linac to accelerate high-brightness electron beam up to {approx} 7 GeV. We propose a design for the electron front end based on a photoinjector and consider the electron beam dynamics along the linac. Start-to-end simulations of the full accelerator for electrons are presented. Finally the potential applications of such an electron beam are outlined.

  10. Gauge/Gravity Duality and Hadron Physics at the Light-Front

    SciTech Connect (OSTI)

    Teramond, Guy F. de [Universidad de Costa Rica, San Jose (Costa Rica); Brodsky, Stanley J. [SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309, USA and CP3-Origins, University of Southern Denmark, Odense, 5230 M (Denmark)

    2010-11-12T23:59:59.000Z

    We discuss some remarkable features of the light-front holographic mapping of classical gravity in anti-de Sitter space modified by a confining dilaton background. In particular, we show that a positive-sign dilaton solution exp(+{kappa}{sup 2}z{sup 2}) has better chances to describe the correct hadronic phenomenology than the negative solution exp(-{kappa}{sup 2}z{sup 2}) extensively studied in the literature. We also show that the use of twist-scaling dimensions, instead of canonical dimensions, is required to give a good description of the spectrum and form factors of hadrons. Another key element is the explicit connection of AdS modes of total angular momentum J with the internal structure of hadrons and the proper identification of the orbital angular momentum of the constituents.

  11. Influence of the bonding front propagation on the wafer stack curvature

    SciTech Connect (OSTI)

    Navarro, E. [SOITEC—Parc Technologique des Fontaines, 38190 Bernin (France); SIMaP—Grenoble-INP, 1340 rue de la Piscine, 38402 St. Martin d'Hères (France); Bréchet, Y. [SIMaP—Grenoble-INP, 1340 rue de la Piscine, 38402 St. Martin d'Hères (France); Barthelemy, A.; Radu, I. [SOITEC—Parc Technologique des Fontaines, 38190 Bernin (France); Pardoen, T. [Institute of Mechanics, Materials and Civil Engineering (iMMC), Université catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Raskin, J.-P. [Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Université catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium)

    2014-08-11T23:59:59.000Z

    The influence of the dynamics of the direct wafer bonding process on the curvature of the final wafer stack is investigated. An analytical model for the final curvature of the bonded wafers is developed, as a function of the different load components acting during the bonding front propagation, using thin plate theory and considering a strain discontinuity locked at the bonding interface. Experimental profiles are measured for different bonding conditions and wafer thicknesses. A very good agreement with the model prediction is obtained and the influence of the thin air layer trapped in-between the two wafers is demonstrated. The proposed model contributes to further improvement of the bonding process, in particular, for the stacking of layers of electronic devices, which requires a high accuracy of wafer-to-wafer alignment and a very low distortion level.

  12. GYROSURFING ACCELERATION OF IONS IN FRONT OF EARTH's QUASI-PARALLEL BOW SHOCK

    SciTech Connect (OSTI)

    Kis, Arpad; Lemperger, Istvan; Wesztergom, Viktor [Research Centre for Astronomy and Earth Sciences, Geodetic and Geophysical Institute, Sopron (Hungary); Agapitov, Oleksiy; Krasnoselskikh, Vladimir [LPC2E/CNRS, F-45071 Orleans (France); Khotyaintsev, Yuri V. [Swedish Institute of Space Physics, SE- 751 21 Uppsala (Sweden); Dandouras, Iannis, E-mail: akis@ggki.hu, E-mail: Kis.Arpad@csfk.mta.hu [CESR, F-31028 Toulouse (France)

    2013-07-01T23:59:59.000Z

    It is well known that shocks in space plasmas can accelerate particles to high energies. However, many details of the shock acceleration mechanism are still unknown. A critical element of shock acceleration is the injection problem; i.e., the presence of the so called seed particle population that is needed for the acceleration to work efficiently. In our case study, we present for the first time observational evidence of gyroresonant surfing acceleration in front of Earth's quasi-parallel bow shock resulting in the appearance of the long-suspected seed particle population. For our analysis, we use simultaneous multi-spacecraft measurements provided by the Cluster spacecraft ion (CIS), magnetic (FGM), and electric field and wave instrument (EFW) during a time period of large inter-spacecraft separation distance. The spacecraft were moving toward the bow shock and were situated in the foreshock region. The results show that the gyroresonance surfing acceleration takes place as a consequence of interaction between circularly polarized monochromatic (or quasi-monochromatic) transversal electromagnetic plasma waves and short large amplitude magnetic structures (SLAMSs). The magnetic mirror force of the SLAMS provides the resonant conditions for the ions trapped by the waves and results in the acceleration of ions. Since wave packets with circular polarization and different kinds of magnetic structures are very commonly observed in front of Earth's quasi-parallel bow shock, the gyroresonant surfing acceleration proves to be an important particle injection mechanism. We also show that seed ions are accelerated directly from the solar wind ion population.

  13. Scintillation counter and wire chamber front end modules for high energy physics experiments

    SciTech Connect (OSTI)

    Baldin, Boris; DalMonte, Lou; /Fermilab

    2011-01-01T23:59:59.000Z

    This document describes two front-end modules developed for the proposed MIPP upgrade (P-960) experiment at Fermilab. The scintillation counter module was developed for the Plastic Ball detector time and charge measurements. The module has eight LEMO 00 input connectors terminated with 50 ohms and accepts negative photomultiplier signals in the range 0.25...1000 pC with the maximum input voltage of 4.0 V. Each input has a passive splitter with integration and differentiation times of {approx}20 ns. The integrated portion of the signal is digitized at 26.55 MHz by Analog Devices AD9229 12-bit pipelined 4-channel ADC. The differentiated signal is discriminated for time measurement and sent to one of the four TMC304 inputs. The 4-channel TMC304 chip allows high precision time measurement of rising and falling edges with {approx}100 ps resolution and has internal digital pipeline. The ADC data is also pipelined which allows deadtime-less operation with trigger decision times of {approx}4 {micro}s. The wire chamber module was developed for MIPP EMCal detector charge measurements. The 32-channel digitizer accepts differential analog signals from four 8-channel integrating wire amplifiers. The connection between wire amplifier and digitizer is provided via 26-wire twist-n-flat cable. The wire amplifier integrates input wire current and has sensitivity of 275 mV/pC and the noise level of {approx}0.013 pC. The digitizer uses the same 12-bit AD9229 ADC chip as the scintillator counter module. The wire amplifier has a built-in test pulser with a mask register to provide testing of the individual channels. Both modules are implemented as a 6Ux220 mm VME size board with 48-pin power connector. A custom europack (VME) 21-slot crate is developed for housing these front-end modules.

  14. Undrilled shallow giant trap in Denver basin, Colorado: mountain-front thrust

    SciTech Connect (OSTI)

    Jacob, A.F.

    1983-03-01T23:59:59.000Z

    Along the southwestern margin of the Denver basin, Precambrian rocks have been upthrusted at least 15,000 ft (4600 m) in the Front Range and 8000 to 10,000 ft (2400 to 3000 m) or more in the Wet Mountains. Below the Precambrian, the precise configuration of the strata and the faults is unknown because there are no available seismic or drilling data, but reasonable interpretations can be made by analogy with other similar areas. Important reservoirs in the basin are the Permian Lyons Sandstone, the Lower Cretaceous J and D sandstones, and the Upper Cretaceous Codell Sandstone, Niobrara Formation, and Pierre Shale. Directly overlying the J are the major hydrocarbon-source rocks in the basin. Black shale is interstratified with the Lyons Sandstone in at least one drill hole in front of the upthrust. All source rocks probably reached maturity in late Cretaceous time and still are generating today. Below the Precambrian, simple upfolding permits an oil column as much as 5000 ft (1500 m) high, or more, the J, and as much as 4000 ft (1200 m) high, or more, in the Lyons, assuming a fault dip of 70/sup 0/ at depth; lower fault dips permit higher oil columns. Clayey fault gouge, breccia, and minute faulting, in a zone that is in many places hundreds of feet wide at the fault, should be a good hydrocarbon seal, like a cork in a tilted 5000-ft (1500 m) high bottle. If the strata roll over to the west to form a large anticline below the Precambrian, a different kind of trap of very large dimensions would be present. Any kind of trap can extend a combined north-south distance of nearly 65 mi (105 km). Even if roll over is absent and the fault dips steeply, drilling depths to most traps are likely to be only several thousand feet.

  15. Measures of the environmental footprint of the front end of the nuclear fuel cycle

    SciTech Connect (OSTI)

    E. Schneider; B. Carlsen; E. Tavrides; C. van der Hoeven; U. Phathanapirom

    2013-11-01T23:59:59.000Z

    Previous estimates of environmental impacts associated with the front end of the nuclear fuel cycle (FEFC) have focused primarily on energy consumption and CO2 emissions. Results have varied widely. This work builds upon reports from operating facilities and other primary data sources to build a database of front end environmental impacts. This work also addresses land transformation and water withdrawals associated with the processes of the FEFC. These processes include uranium extraction, conversion, enrichment, fuel fabrication, depleted uranium disposition, and transportation. To allow summing the impacts across processes, all impacts were normalized per tonne of natural uranium mined as well as per MWh(e) of electricity produced, a more conventional unit for measuring environmental impacts that facilitates comparison with other studies. This conversion was based on mass balances and process efficiencies associated with the current once-through LWR fuel cycle. Total energy input is calculated at 8.7 x 10- 3 GJ(e)/MWh(e) of electricity and 5.9 x 10- 3 GJ(t)/MWh(e) of thermal energy. It is dominated by the energy required for uranium extraction, conversion to fluoride compound for subsequent enrichment, and enrichment. An estimate of the carbon footprint is made from the direct energy consumption at 1.7 kg CO2/MWh(e). Water use is likewise dominated by requirements of uranium extraction, totaling 154 L/MWh(e). Land use is calculated at 8 x 10- 3 m2/MWh(e), over 90% of which is due to uranium extraction. Quantified impacts are limited to those resulting from activities performed within the FEFC process facilities (i.e. within the plant gates). Energy embodied in material inputs such as process chemicals and fuel cladding is identified but not explicitly quantified in this study. Inclusion of indirect energy associated with embodied energy as well as construction and decommissioning of facilities could increase the FEFC energy intensity estimate by a factor of up to 2.

  16. Cast Stone Oxidation Front Evaluation: Preliminary Results For Samples Exposed To Moist Air

    SciTech Connect (OSTI)

    Langton, C. A.; Almond, P. M.

    2013-11-26T23:59:59.000Z

    The rate of oxidation is important to the long-term performance of reducing salt waste forms because the solubility of some contaminants, e.g., technetium, is a function of oxidation state. TcO{sub 4}{sup ?} in the salt solution is reduced to Tc(IV) and has been shown to react with ingredients in the waste form to precipitate low solubility sulfide and/or oxide phases. Upon exposure to oxygen, the compounds containing Tc(IV) oxidize to the pertechnetate ion, Tc(VII)O{sub 4}{sup ?}, which is very soluble. Consequently the rate of technetium oxidation front advancement into a monolith and the technetium leaching profile as a function of depth from an exposed surface are important to waste form performance and ground water concentration predictions. An approach for measuring contaminant oxidation rate (effective contaminant specific oxidation rate) based on leaching of select contaminants of concern is described in this report. In addition, the relationship between reduction capacity and contaminant oxidation is addressed. Chromate (Cr(VI) was used as a non-radioactive surrogate for pertechnetate, Tc(VII), in Cast Stone samples prepared with 5 M Simulant. Cast Stone spiked with pertechnetate was also prepared and tested. Depth discrete subsamples spiked with Cr were cut from Cast Stone exposed to Savannah River Site (SRS) outdoor ambient temperature fluctuations and moist air. Depth discrete subsamples spiked with Tc-99 were cut from Cast Stone exposed to laboratory ambient temperature fluctuations and moist air. Similar conditions are expected to be encountered in the Cast Stone curing container. The leachability of Cr and Tc-99 and the reduction capacities, measured by the Angus-Glasser method, were determined for each subsample as a function of depth from the exposed surface. The results obtained to date were focused on continued method development and are preliminary and apply to the sample composition and curing / exposure conditions described in this report. The Cr oxidation front (depth to which soluble Cr was detected) for the Cast Stone sample exposed for 68 days to ambient outdoor temperatures and humid air (total age of sample was 131 days) was determined to be about 35 mm below the top sample surface exposed. The Tc oxidation front, depth at which Tc was insoluble, was not determined. Interpretation of the results indicates that the oxidation front is at least 38 mm below the exposed surface. The sample used for this measurement was exposed to ambient laboratory conditions and humid air for 50 days. The total age of the sample was 98 days. Technetium appears to be more easily oxidized than Cr in the Cast Stone matrix. The oxidized forms of Tc and Cr are soluble and therefore leachable. Longer exposure times are required for both the Cr and Tc spiked samples to better interpret the rate of oxidation. Tc spiked subsamples need to be taken further from the exposed surface to better define and interpret the leachable Tc profile. Finally Tc(VII) reduction to Tc(IV) appears to occur relatively fast. Results demonstrated that about 95 percent of the Tc(VII) was reduced to Tc(IV) during the setting and very early stage setting for a Cast Stone sample cured 10 days. Additional testing at longer curing times is required to determine whether additional time is required to reduce 100 % of the Tc(VII) in Cast Stone or whether the Tc loading exceeded the ability of the waste form to reduce 100 % of the Tc(VII). Additional testing is required for samples cured for longer times. Depth discrete subsampling in a nitrogen glove box is also required to determine whether the 5 percent Tc extracted from the subsamples was the result of the sampling process which took place in air. Reduction capacity measurements (per the Angus-Glasser method) performed on depth discrete samples could not be correlated with the amount of chromium or technetium leached from the depth discrete subsamples or with the oxidation front inferred from soluble chromium and technetium (i.e., effective Cr and Tc oxidation fronts). Residual reduction capacity

  17. Crash Injury Prediction and Vehicle Damage Reporting by Paramedics: A Feasibility Study

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    of agreement for front airbag deployment, steering wheelPrediction by Paramedics type, airbag deployment, steeringThe investigator assessed airbag deployment by inspecting

  18. A real-world application of lane-guidance technologies - Automated snowblower

    E-Print Network [OSTI]

    Tan, Han-Shue; Bu, Fanping; Bougler, Benedicte

    2007-01-01T23:59:59.000Z

    modeling the low-speed tire- induced oscillation, designing high-gain automatic control on front wheels while keeping rear steering

  19. Technical Cost Modeling - Life Cycle Analysis Basis for Program...

    Broader source: Energy.gov (indexed) [DOE]

    185 HP, Port Fuel Injected, V6 Aluminum, 4 Valves per Cylinder, Naturally aspirated (No Turbo)) - Transmission (Front Wheel Drive, Locking Automatic) - Fuel Economy and...

  20. Partial Solar Eclipse Watch Party More than 100 people joined us on Thursday, October 23 to watch as the Moon slipped in front of the Sun during

    E-Print Network [OSTI]

    Huang, Haiying

    as the Moon slipped in front of the Sun during a partial solar eclipse. We had telescopes and cameras set up to safely view the Sun. Solar glasses were available for purchase in the ticket booth. News stations from that the total gravity force on Earth is increased during a total eclipse, when the Moon goes in front of the Sun

  1. Journal of Statistical Physics, Vol. 90, Nos. 5/6, 1998 We study the nucleation and growth of flame fronts in slow combustion. This

    E-Print Network [OSTI]

    Grant, Martin

    fronts in slow combustion. This is modeled by a set of reaction-diffusion equations for the temperature: Nucleation; reaction-diffusion systems; flame fronts. Nucleation, Growth, and Scaling in Slow Combustion applied to understand some aspects of slow combustion. We use a phase-field model of two coupled reaction

  2. Submitted to EUROSPEECH 2003, September 1-4, 2003 -Geneva, Switzerland Enhancement of Noisy Speech for Noise Robust Front-End and Speech

    E-Print Network [OSTI]

    Wichmann, Felix

    Submitted to EUROSPEECH 2003, September 1-4, 2003 - Geneva, Switzerland Enhancement of Noisy Speech enhancement method for noise ro- bust front-end and speech reconstruction at the back-end of Dis- tributed. 2. Noise robust front-end algorithm The speech enhancement methods in combination with feature

  3. January/February 2000 2000, Elsevier Science Inc., 1040-6190/00/$see front matter PII S1040-6190(99)00102-5 25 Health Effects of

    E-Print Network [OSTI]

    Illinois at Chicago, University of

    January/February 2000 © 2000, Elsevier Science Inc., 1040-6190/00/$­see front matter PII S1040-6190/00/$­see front matter PII S1040-6190(99)00102-5 The Electricity Journal Paul Brodeur in The New Yorker

  4. Robust ASR front-end using spectral-based and discriminant features: experiments on the Aurora tasks

    E-Print Network [OSTI]

    Dupont, Stéphane

    Robust ASR front-end using spectral-based and discriminant features: experiments on the Aurora was tested on the set of speech corpora used for the "Aurora" evaluation. Using the feature stream generated and server side ASR processing, a standartization initiative called "Aurora" was initiated within European

  5. ICPIG, July 15-20, 2007, Prague, Czech Republi Negative streamer fronts: comparison of particle and fluid models and

    E-Print Network [OSTI]

    Ebert, Ute

    that propagates into non-ionized matter. Streamers are used in industrial applications such as ozone generation28th ICPIG, July 15-20, 2007, Prague, Czech Republi Negative streamer fronts: comparison be generated during early stages of the lighting event. Both questions require a fully kinetic description

  6. Parameterization of GDL Liquid Water Front Propagation and Channel Accumulation for Anode Purge Scheduling in Fuel Cells

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Parameterization of GDL Liquid Water Front Propagation and Channel Accumulation for Anode Purge, and (2) accumulation and transport of liquid water in the Gas Diffusion Layer (GDL) originally presented experimentally iden- tified parameter to match the rate of liquid water accumulation in the anode channel

  7. 2440 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 49, NO. 5, OCTOBER 2002 The Programmable Front-End System for

    E-Print Network [OSTI]

    . A significant feature of our design is its capability for in situ DC characterization of each bolometer--Detector biasing, electronics for bolometric detec- tors, front-end readout, high-input impedance circuit, low- tinuous monitoring of the detector baseline. The CUORICINO [4] experiment plans to measure an array of 60

  8. Pinning and mode-locking of reaction fronts by vortices Garrett M. O'Malley, Matthew S. Paoletti 1

    E-Print Network [OSTI]

    Solomon, Tom

    . In the presence of a uniform ``wind'', the front often freezes, remaining pinned to the leading vortex and neither not understood, even for well-ordered, laminar flows. In many cases, transport in a fluid flow is diffusive and instead concentrate on extensions of FKPP theory to cases where the transport is superdiffusive with hr2 i

  9. Temperature activated absorption during laser-induced damage: The evolution of laser-supported solid-state absorption fronts

    SciTech Connect (OSTI)

    Carr, C W; Bude, J D; Shen, N; Demange, P

    2010-10-26T23:59:59.000Z

    Previously we have shown that the size of laser induced damage sites in both KDP and SiO{sub 2} is largely governed by the duration of the laser pulse which creates them. Here we present a model based on experiment and simulation that accounts for this behavior. Specifically, we show that solid-state laser-supported absorption fronts are generated during a damage event and that these fronts propagate at constant velocities for laser intensities up to 4 GW/cm{sup 2}. It is the constant absorption front velocity that leads to the dependence of laser damage site size on pulse duration. We show that these absorption fronts are driven principally by the temperature-activated deep sub band-gap optical absorptivity, free electron transport, and thermal diffusion in defect-free silica for temperatures up to 15,000K and pressures < 15GPa. In addition to the practical application of selecting an optimal laser for pre-initiation of large aperture optics, this work serves as a platform for understanding general laser-matter interactions in dielectrics under a variety of conditions.

  10. TRENDS in Ecology & Evolution Vol.17 No.7 July 2002 http://tree.trends.com 0169-5347/02/$ see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S0169-5347(02)02506-5

    E-Print Network [OSTI]

    Rosenberg, Noah

    front matter © 2002 Elsevier Science Ltd. All rights reserved. PII: S0169-5347(02)02506-5 301Research

  11. 482 0169-5347/00/$ see front matter 2000 Elsevier Science Ltd. All rights reserved. PII: S0169-5347(00)01966-2 TREE vol. 15, no. 12 December 2000 hybrid incompatibility factors by the introgression

    E-Print Network [OSTI]

    Flaxman, Samuel M.

    482 0169-5347/00/$ ­ see front matter © 2000 Elsevier Science Ltd. All rights reserved. PII: S0169

  12. TRENDS in Biotechnology Vol.20 No.10 October 2002 http://tibtech.trends.com 0167-7799/02/$ see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S0167-7799(02)02047-4

    E-Print Network [OSTI]

    Lebendiker, Mario

    front matter © 2002 Elsevier Science Ltd. All rights reserved. PII: S0167-7799(02)02047-4 437Review

  13. TRENDS in Biotechnology Vol.20 No.10 October 2002 http://tibtech.trends.com 0167-7799/02/$ see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S0167-7799(02)02032-2

    E-Print Network [OSTI]

    Babu, M. Madan

    front matter © 2002 Elsevier Science Ltd. All rights reserved. PII: S0167-7799(02)02032-2 407Research

  14. Nonperturbative QCD coupling and its {beta} function from light-front holography

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; Teramond, Guy F. de; Deur, Alexandre [SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309 (United States); CP3-Origins, University of Southern Denmark, Odense, 5230 M (Denmark); Universidad de Costa Rica, San Jose (Costa Rica); Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

    2010-05-01T23:59:59.000Z

    The light-front holographic mapping of classical gravity in anti-de Sitter space, modified by a positive-sign dilaton background, leads to a nonperturbative effective coupling {alpha}{sub s}{sup AdS}(Q{sup 2}). It agrees with hadron physics data extracted from different observables, such as the effective charge defined by the Bjorken sum rule, as well as with the predictions of models with built-in confinement and lattice simulations. It also displays a transition from perturbative to nonperturbative conformal regimes at a momentum scale {approx}1 GeV. The resulting {beta} function appears to capture the essential characteristics of the full {beta} function of QCD, thus giving further support to the application of the gauge/gravity duality to the confining dynamics of strongly coupled QCD. Commensurate scale relations relate observables to each other without scheme or scale ambiguity. In this paper we extrapolate these relations to the nonperturbative domain, thus extending the range of predictions based on {alpha}{sub s}{sup AdS}(Q{sup 2}).

  15. Electromagnetic energy conversion in downstream fronts from three dimensional kinetic reconnection

    SciTech Connect (OSTI)

    Lapenta, Giovanni [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium)] [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium); Goldman, Martin; Newman, David [University of Colorado, Colorado 80309 (United States)] [University of Colorado, Colorado 80309 (United States); Markidis, Stefano [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden)] [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden); Divin, Andrey [Swedish Institute of Space Physics, Uppsala (Sweden)] [Swedish Institute of Space Physics, Uppsala (Sweden)

    2014-05-15T23:59:59.000Z

    The electromagnetic energy equation is analyzed term by term in a 3D simulation of kinetic reconnection previously reported by Vapirev et al. [J. Geophys. Res.: Space Phys. 118, 1435 (2013)]. The evolution presents the usual 2D-like topological structures caused by an initial perturbation independent of the third dimension. However, downstream of the reconnection site, where the jetting plasma encounters the yet unperturbed pre-existing plasma, a downstream front is formed and made unstable by the strong density gradient and the unfavorable local acceleration field. The energy exchange between plasma and fields is most intense at the instability, reaching several pW/m{sup 3}, alternating between load (energy going from fields to particles) and generator (energy going from particles to fields) regions. Energy exchange is instead purely that of a load at the reconnection site itself in a region focused around the x-line and elongated along the separatrix surfaces. Poynting fluxes are generated at all energy exchange regions and travel away from the reconnection site transporting an energy signal of the order of about S?10{sup ?3}W/m{sup 2}.

  16. Magnetic field effects on the thermonuclear combustion front of Chandrasekhar mass white dwarfs

    E-Print Network [OSTI]

    Cristian R. Ghezzi; Elisabete M. de Gouveia Dal Pino; Jorge E. Horvath

    2000-12-06T23:59:59.000Z

    The explosion of a type Ia supernova starts in a white dwarf as a laminar deflagration at the center of the star and soon several hydrodynamic instabilities, in particular, the Rayleigh-Taylor instability, begin to act. A cellular stationary combustion and a turbulent combustion regime are rapidly achieved by the flame and maintained up to the end of the so-called flamelet regime when the transition to detonation is believed to occur. The burning velocity at these regimes is well described by the fractal model of combustion. Using a semi-analytic approach, we describe the effect of magnetic fields on the fractalization of the front considering a white dwarf with a nearly dipolar magnetic field. We find an intrinsic asymmetry on the velocity field that may be maintained up to the free expansion phase of the remnant. Considering the strongest values inferred for a white dwarf's magnetic fields with strengths up to $10^{8}-10^{9}$ G at the surface and assuming that the field near the centre is roughly 10 times greater, asymmetries in the velocity field higher than $10-20 %$ are produced between the magnetic polar and the equatorial axis of the remnant which may be related to the asymmetries found from recent spectropolarimetric observations of very young SN Ia remnants. Dependence of the asymmetry with white dwarf composition is also analyzed.

  17. A Prototype Front-End Readout Chip for Silicon Microstrip Detectors Using an Advanced SiGe Technology

    E-Print Network [OSTI]

    Grillo, A A; Daniel, L; Horn, G; Martchovsky, A; Martinez-McKinney, F; Sadrozinski, H F W; Seiden, A; Wilder, M

    2009-01-01T23:59:59.000Z

    The upgrade of the ATLAS detector for the high luminosity upgrade of the LHC will require a rebuild of the Inner Detector as well as replacement of the readout electronics of the Liquid Argon Calorimeter and other detector components. We proposed some time ago to study silicon germanium (SiGe) BiCMOS technologies as a possible choice for the required silicon microstrip and calorimeter front-end chips given that they showed promise to provide necessary low noise at low power. Evaluation of the radiation hardness of these technologies has been under study. To validate the expected performance of these technologies, we designed and fabricated an 8-channel front-end readout chip for a silicon microstrip detector using the IBM 8WL technology, a likely choice for the ATLAS upgrade. Preliminary electrical characteristics of this chip will be presented.

  18. The Electromagnetic Gauge Field Interpolation between the Instant Form and the Front Form of the Hamiltonian Dynamics

    E-Print Network [OSTI]

    Chueng-Ryong Ji; Ziyue Li; Alfredo Takashi Suzuki

    2014-12-08T23:59:59.000Z

    We present the electromagnetic gauge field interpolation between the instant form and the front form of the relativistic Hamiltonian dynamics and extend our interpolation of the scattering amplitude presented in the simple scalar field theory to the case of the electromagnetic gauge field theory with the scalar fermion fields known as the sQED theory. We find that the Coulomb gauge in the instant form dynamics (IFD) and the light-front gauge in the front form dynamics, or the light-front dynamics (LFD), are naturally linked by the unified general physical gauge that interpolates between these two forms of dynamics and derive the spin-1 polarization vector for the photon that can be generally applicable for any interpolation angle. Corresponding photon propagator for an arbitrary interpolation angle is found and examined in terms of the gauge field polarization and the interpolating time ordering. Using these results, we calculate the lowest-order scattering processes for an arbitrary interpolation angle in sQED. We provide an example of breaking the reflection symmetry under the longitudinal boost, $P^z \\leftrightarrow -P^z$, for the time-ordered scattering amplitude in any interpolating dynamics except the LFD and clarify the confusion in the prevailing notion of the equivalence between the infinite momentum frame (IMF) and the LFD. The particular correlation found in our previous analysis of the scattering amplitude in the simple scalar field theory, coined as the J-shaped correlation, between the total momentum of the system and the interpolation angle persists in the present analysis of the sQED scattering amplitude. We discuss the singular behavior of this correlation in conjunction with the zero-mode issue in the LFD.

  19. Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    E-Print Network [OSTI]

    Brodsky, S J; Hwang, D S

    2006-01-01T23:59:59.000Z

    We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo ...

  20. Discrete Symmetries on the Light Front and a General Relation connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC; Gardner, Susan; /Kentucky U.; Hwang, Dae Sung; /Sejong U.

    2006-01-11T23:59:59.000Z

    We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n} {approx} -{kappa}{sup p}.

  1. Discrete symmetries on the light front and a general relation connecting the nucleon electric dipole and anomalous magnetic moments

    SciTech Connect (OSTI)

    Brodsky, Stanley J. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States); Gardner, Susan [Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055 (United States); Hwang, Dae Sung [Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of)

    2006-02-01T23:59:59.000Z

    We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n}{approx}-{kappa}{sup p}.

  2. Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    E-Print Network [OSTI]

    S. J. Brodsky; S. Gardner; D. S. Hwang

    2006-02-27T23:59:59.000Z

    We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, kappa^n ~ - kappa^p.

  3. Particle Acceleration Zones Above Pulsar Polar Caps: Electron and Positron Pair Formation Fronts

    E-Print Network [OSTI]

    Alice K. Harding; Alexander G. Muslimov

    1998-05-11T23:59:59.000Z

    We investigate self-consistent particle acceleration near a pulsar polar cap (PC) by the electrostatic field due to the effect of inertial frame dragging. Test particles gain energy from the electric field parallel to the open magnetic field lines and lose energy by both curvature radiation (CR) and resonant and non-resonant inverse Compton scattering (ICS) with soft thermal X-rays from the neutron star (NS) surface. Gamma-rays radiated by electrons accelerated from the stellar surface produce pairs in the strong magnetic field, which screen the electric field beyond a pair formation front (PFF). Some of the created positrons can be accelerated back toward the surface and produce gamma-rays and pairs that create another PFF above the surface. We find that ICS photons control PFF formation near the surface, but due to the different angles at which the electron and positron scatter the soft photons, positron initiated cascades develop above the surface and screen the accelerating electric field. Stable acceleration from the NS surface is therefore not possible in the presence of dominant ICS energy losses. However, we find that stable acceleration zones may occur at some distance above the surface, where CR dominates the electron and positron energy losses, and there is up-down symmetry between the electron and positron PFFs. We examine the dependence of CR-controlled acceleration zone voltage, width and height above the surface on parameters of the pulsar and its soft X-ray emission. For most pulsars, we find that acceleration will start at a height of 0.5 - 1 stellar radii above the NS surface.

  4. THE WAVE PROPERTIES OF CORONAL BRIGHT FRONTS OBSERVED USING SDO/AIA

    SciTech Connect (OSTI)

    Long, David M.; DeLuca, Edward E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gallagher, Peter T., E-mail: longda@tcd.ie [Astrophysics Research Group, School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

    2011-11-15T23:59:59.000Z

    Coronal bright fronts (CBFs) are large-scale wavefronts that propagate through the solar corona at hundreds of kilometers per second. While their kinematics have been studied in detail, many questions remain regarding the temporal evolution of their amplitude and pulse width. Here, contemporaneous high cadence, multi-thermal observations of the solar corona from the Solar Dynamic Observatory (SDO) and Solar TErrestrial RElations Observatory (STEREO) spacecraft are used to determine the kinematics and expansion rate of a CBF wavefront observed on 2010 August 14. The CBF was found to have a lower initial velocity with weaker deceleration in STEREO observations compared to SDO observations ({approx}340 km s{sup -1} and -72 m s{sup -2} as opposed to {approx}410 km s{sup -1} and -279 m s{sup -2}). The CBF kinematics from SDO were found to be highly passband-dependent, with an initial velocity ranging from 379 {+-} 12 km s{sup -1} to 460 {+-} 28 km s{sup -1} and acceleration ranging from -128 {+-} 28 m s{sup -2} to -431 {+-} 86 m s{sup -2} in the 335 A and 304 A passbands, respectively. These kinematics were used to estimate a quiet coronal magnetic field strength range of {approx}1-2 G. Significant pulse broadening was also observed, with expansion rates of {approx}130 km s{sup -1} (STEREO) and {approx}220 km s{sup -1} (SDO). By treating the CBF as a linear superposition of sinusoidal waves within a Gaussian envelope, the resulting dispersion rate of the pulse was found to be {approx}8-13 Mm{sup 2} s{sup -1}. These results are indicative of a fast-mode magnetoacoustic wave pulse propagating through an inhomogeneous medium.

  5. Implications of Canada, snow, and white-fronted geese and Northern bobwhite as disease reservoirs for the Attwater's prairie-chicken

    E-Print Network [OSTI]

    Purvis, Jonny Ray

    1995-01-01T23:59:59.000Z

    , 10 Canada (Branta canadensis), 24 snow (Chen caerulescens), and 22 white-fronted geese (Anser albifrons) were examined for endoparasites. Northern bobwhite (Colinus virginianus) (n = 62), the closest relative of Attwater's prairie...

  6. Chemical Effects at the Reaction Front in Corroding Spent Nuclear Fuel

    SciTech Connect (OSTI)

    Fortner, Jeffrey A.; Kropf, A. Jeremy; Jerden, James L.; Cunnane, James C. [Chemical Engineering, Argonne National Laboratory, CMT/205, 9700 S. Cass Avenue, Argonne, IL, 60439 (United States)

    2007-07-01T23:59:59.000Z

    Performance assessment models of the U. S. repository at Yucca Mountain, Nevada suggest that neptunium from spent nuclear fuel is a potentially important dose contributor. A scientific understanding of how the UO{sub 2} matrix of spent nuclear fuel impacts the oxidative dissolution and reductive precipitation of Np is needed to predict the behavior of Np at the fuel surface during aqueous corrosion. Neptunium would most likely be transported as aqueous Np(V) species, but for this to occur it must first be oxidized from the Np(IV) state found within the parent spent nuclear fuel. In this paper we present synchrotron X-ray absorption spectroscopy and microscopy findings that illuminate the resultant local chemistry of neptunium and plutonium within uranium oxide spent nuclear fuel before and after corrosive alteration in an air-saturated aqueous environment. We find the Pu and Np in unaltered spent fuel to have a +4 oxidation state and an environment consistent with solid-solution in the UO{sub 2} matrix. During corrosion in an air-saturated aqueous environment, the uranium matrix is converted to uranyl (UO{sub 2}{sup 2+}) mineral assemblage that is depleted in Np and Pu relative to the parent fuel. The transition from U(IV) in the fuel to a fully U(VI) character across the corrosion front is not sharp, but occurs over a transition zone of {approx} 50 micrometers. We find evidence of a thin ({approx} 20 micrometer) layer that is enriched in Pu and Np within a predominantly U(IV) environment on the fuel side of the transition zone. These experimental observations are consistent with available data for the standard reduction potentials for NpO{sub 2}{sup +}/Np{sup 4+} and UO{sub 2}{sup 2+}/U{sup 4+} couples, which indicate that Np(IV) may not be effectively oxidized to Np(V) at the corrosion potential of uranium dioxide spent nuclear fuel in air-saturated aqueous solutions. (authors)

  7. Nucleon electromagnetic form factors and electroexcitation of low lying nucleon resonances in a light-front relativistic quark model

    SciTech Connect (OSTI)

    Aznauryan Inna, Burkert Volker

    2012-05-01T23:59:59.000Z

    We utilize a light-front relativistic quark model (LF RQM) to predict the 3q core contribution to the electroexcitation amplitudes for the {Delta}(1232)P{sub 33}, N(1440)P{sub 11}, N(1520)D{sub 13}, and N(1535)S{sub 11} up to Q{sup 2} = 12 GeV{sup 2}. The parameters of the model have been specified via description of the nucleon electromagnetic form factors in the approach that combines 3q and pion-cloud contributions in the LF dynamics.

  8. Effect of Front-Side Silver Metallization on Underlying n+-p Junction in Multicrystalline Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Li, Z. G.; Moutinho, H. R.; Liang, L.; Ionkin, A.; Al-Jassim, M. M.

    2012-06-01T23:59:59.000Z

    We report on the effect of front-side Ag metallization on the underlying n+-p junction of multicrystalline Si solar cells. The junction quality beneath the contacts was investigated by characterizing the uniformities of the electrostatic potential and doping concentration across the junction, using scanning Kelvin probe force microscopy and scanning capacitance microscopy. We investigated cells with a commercial Ag paste (DuPont PV159) and fired at furnace setting temperatures of 800 degrees, 840 degrees, and 930 degrees C, which results in actual cell temperatures ~100 degrees C lower than the setting temperature and the three cells being under-, optimal-, and over-fired. We found that the uniformity of the junction beneath the Ag contact was significantly degraded by the over-firing, whereas the junction retained good uniformity with the optimal- and under-fire temperatures. Further, Ag crystallites with widely distributed sizes from <100 nm to several ?m were found at the Ag/Si interface of the over-fired cell. Large crystallites were imaged as protrusions into Si deeper than the junction depth. However, the junction was not broken down; instead, it was reformed on the entire front of the crystallite/Si interface. We propose a mechanism of the junction-quality degradation, based on emitter Si melting at the temperature around the Ag-Si eutectic point during firing, and subsequent recrystallization with incorporation of impurities in the Ag paste and with formation of crystallographic defects during quenching.

  9. TRENDS in Cognitive Sciences Vol.5 No.12 December 2001 http://tics.trends.com 1364-6613/01/$ see front matter 2001 Elsevier Science Ltd.All rights reserved. PII: S1364-6613(00)01803-9

    E-Print Network [OSTI]

    Coulson, Seana

    front matter © 2001 Elsevier Science Ltd.All rights reserved. PII: S1364-6613(00)01803-9 517Opinion Afew

  10. TRENDS in Biotechnology Vol.19 No.12 December 2001 http://tibtech.trends.com 0167-7799/01/$ see front matter 2001 Elsevier Science Ltd.All rights reserved. PII: S0167-7799(01)01813-3

    E-Print Network [OSTI]

    Gough, Julian

    front matter © 2001 Elsevier Science Ltd.All rights reserved. PII: S0167-7799(01)01813-3 482 Research

  11. Comparison among Hamiltonian light-front formalisms at q+ = 0 and q+ 0: space-like elastic form factors of pseudoscalar and vector mesons

    E-Print Network [OSTI]

    Silvano Simula

    2002-08-07T23:59:59.000Z

    The electromagnetic elastic form factors of pseudoscalar and vector mesons are analyzed for space-like momentum transfers in terms of relativistic quark models based on the Hamiltonian light-front formalism elaborated in different reference frames (q+ 0 and q+ 0). As far as the one-body approximation for the electromagnetic current operator is concerned, it is shown that the predictions of the light-front approach at q+=0 should be preferred, particularly in case of light hadrons, because of: i) the relevant role played by the Z-graph at q+ 0, and ii) the appropriate elimination of spurious effects, related to the orientation of the null hyperplane where the light-front wave function is defined.

  12. LPV methods for fault-tolerant vehicle dynamic control Olivier Sename, Juan-Carlos Tudon-Martinez, Soheib Fergani

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the semi-active suspension control problem and the yaw control using braking, steering and suspension gain-scheduled H vehicle dynamic stability controller, involving front steer- ing, rear braking and safety of vehicle occupants [1], [2]. Analysis, modeling and control of the overall vehicle dy- namics

  13. Design and construction of the front-end electronics data acquisition for the SLD CRID (Cherenkov Ring Imaging Detector)

    SciTech Connect (OSTI)

    Hoeflich, J.; McShurley, D.; Marshall, D.; Oxoby, G.; Shapiro, S.; Stiles, P. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Spencer, E. (California Univ., Santa Cruz, CA (USA). Inst. for Particle Physics)

    1990-10-01T23:59:59.000Z

    We describe the front-end electronics for the Cherenkov Ring Imaging Detector (CRID) of the SLD at the Stanford Linear Accelerator Center. The design philosophy and implementation are discussed with emphasis on the low-noise hybrid amplifiers, signal processing and data acquisition electronics. The system receives signals from a highly efficient single-photo electron detector. These signals are shaped and amplified before being stored in an analog memory and processed by a digitizing system. The data from several ADCs are multiplexed and transmitted via fiber optics to the SLD FASTBUS system. We highlight the technologies used, as well as the space, power dissipation, and environmental constraints imposed on the system. 16 refs., 10 figs.

  14. Considerations on the design of front-end electronics for silicon calorimetry for the SSC (Superconducting Super Collider)

    SciTech Connect (OSTI)

    Wintenberg, A.L.; Bauer, M.L.; Britton, C.L. Jr.; Kennedy, E.J.; Todd, R.A. (Oak Ridge National Lab., TN (USA)); Berridge, S.C.; Bugg, W.M. (Tennessee Univ., Knoxville, TN (USA))

    1990-01-01T23:59:59.000Z

    Some considerations are described for the design of a silicon-based sampling calorimetry detector for the Superconducting Super Collider (SSC). The use of silicon as the detection medium allows fast, accurate, and fine-grained energy measurements -- but for optimal performance, the front-end electronics must be matched to the detector characteristics and have the speed required by the high SSC interaction rates. The relation between the signal-to-noise ratio of the calorimeter electronics and the charge collection time, the preamplifier power dissipation, detector capacitance and leakage, charge gain, and signal shaping and sampling was studied. The electrostatic transformer connection was analyzed and found to be unusable for a tightly arranged calorimeter because of stray capacitance effects. The method of deconvolutional sampling was developed as a means for pileup correction following synchronous sampling and analog storage. 3 refs., 6 figs.

  15. Influence of the pattern shape on the photonic efficiency of front-side periodically patterned ultrathin crystalline silicon solar cells

    E-Print Network [OSTI]

    Herman, Aline; Depauw, Valerie; Daif, Ounsi El; Deparis, Olivier

    2012-01-01T23:59:59.000Z

    Patterning the front side of an ultra-thin crystalline silicon (c Si) solar cell helps keeping the energy conversion efficiency high by compensating for the light absorption losses. A super-Gaussian mathematical expression was used in order to encompass a large variety of nanopattern shapes and to study their influence on the photonic performance. We prove that the enhancement in the maximum achievable photo-current is due to both impedance matching condition at short wavelengths and to the wave nature of light at longer wavelengths. We show that the optimal mathematical shape and parameters of the pattern depend on the c Si thickness. An optimal shape comes with a broad optimal parameter zone where fabricating errors would have much less influence on the efficiency. We prove that cylinders are not the best suited shape. To compare our model with a real slab, we fabricated a nanopatterned c Si slab via Nano Imprint Lithography.

  16. VOLUME 78, NUMBER 6 P H Y S I C A L R E V I E W L E T T E R S 10 FEBRUARY 1997 The Dynamics of Curved Fronts: Beyond Geometry

    E-Print Network [OSTI]

    Hagberg, Aric

    kinematic approach for front motion in two-dimensional bistable media that captures spontaneous spiral-wave (Received 13 September 1996) We derive a new set of kinematic equations for front motion in two. The resulting equations capture the core structure of spiral waves and spontaneous spiral-wave nucleation. [S

  17. ABSTRACT: FRANKEL K.L. & PAZZAGLIA F.J., Tectonic geomorpholo-gy, drainage basin metrics, and active mountain fronts. (IT ISSN 1724-

    E-Print Network [OSTI]

    Frankel, Kurt L.

    and deformational style in the western United States and Italy. Our study is guided by initial results obtained from United States. We attribute the higher variance to the effects of overall larger drainage basin size settings. Here we report results from test cases on five mountain fronts with variable rates of rock uplift

  18. A Nested Micro-Scale Simulation of a Lake Michigan Land-Breeze Front Gijs de Boer,Gregory J.Tripoli,Edwin W.Eloranta

    E-Print Network [OSTI]

    Eloranta, Edwin W.

    Experiments (LAKE-ICE) on 21 December 1997,the University of Wisconsin Volume Imaging Lidar (UW-VIL) observedA Nested Micro-Scale Simulation of a Lake Michigan Land-Breeze Front Gijs de Boer,Gregory J.Tripoli,Edwin W.Eloranta Department of Atmospheric and Oceanic Sciences,The University of Wisconsin - Madison

  19. ICPIG, July 15-20, 2007, Prague, Czech Republic C9 Heavy particle impact excitation of atomic oxygen in front of the powered

    E-Print Network [OSTI]

    Fehske, Holger

    was assumed. Collision between O2 + and the background gas O2 generate electronically excited atomic oxygen oxygen in front of the powered electrode of oxygen rf plasmas ­ Experiment and PIC-Simulation K. Dittmann) resolved plasma induced optical emission of the atomic oxygen in an asymmetrical oxygen rf plasma (CCP

  20. Safety-critical design of the Generic Driving Actuator

    E-Print Network [OSTI]

    Cuijpers, Pieter

    the same interfaces as a human driver does: it controls the steering wheel, the brake pedal and the throttle pedal. The GDA consists of three robots to control each interface: a steering robot and two pedal- quirements a software model is built in the proces-algebraic language µCRL. The requirements

  1. Fault-tolerance in an Embedded Steering Robot: a hybrid approach

    E-Print Network [OSTI]

    Cuijpers, Pieter

    , i.e. using the actual steering wheel, fuel paddle and braking paddle. For such an autonomous robot is a device capable of driving a vehicle fully automatically using the same interface as a human driver does- lab/Simulink to simulate the behavior of the whole system: vehicle, robot and embedded software

  2. Numerical solutions of sheath structures in front of an electron-emitting electrode immersed in a low-density plasma

    SciTech Connect (OSTI)

    Din, Alif [Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, 44000 Islamabad (Pakistan)] [Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, 44000 Islamabad (Pakistan)

    2013-09-15T23:59:59.000Z

    The exact theoretical expressions involved in the formation of sheath in front of an electron emitting electrode immersed in a low-density plasma have been derived. The potential profile in the sheath region has been calculated for subcritical, critical, and supercritical emissions. The potential profiles of critical and supercritical emissions reveals that we must take into account a small, instead of zero, electric field at the sheath edge to satisfy the boundary conditions used to integrate the Poisson's equation. The I-V curves for critical emission shows that only high values of plasma-electron to emitted-electron temperature ratio can meet the floating potential of the emissive electrode. A one-dimensional fluid like model is assumed for ions, while the electron species are treated as kinetic. The distribution of emitted-electron from the electrode is assumed to be half Maxwellian. The plasma-electron enters the sheath region at sheath edge with half Maxwellian velocity distribution, while the reflected ones have cut-off velocity distribution due to the absorption of super thermal electrons by the electrode. The effect of varying emitted-electron current on the sheath structure has been studied with the help of a parameter G (the ratio of emitted-electron to plasma-electron densities)

  3. Design of a Modular Multilevel Converter as an Active Front-End for a magnet supply application

    E-Print Network [OSTI]

    Panagiotis, Asimakopoulos; Massimo, Bongiorno

    2015-01-01T23:59:59.000Z

    The aim of this work is to describe the general design procedure of a Modular Multilevel Converter (MMC) applied as an Active Front-End (AFE) for a magnet supply for beam accelerators. The dimensioning criteria for the converter and the dc-link capacitance are presented and the grid transformer requirements are set. Considering the converter design, the arm inductance calculation is based on the specifications for the arm-current ripple and the DC-link fault tolerance, but, also, on the limitation of the second harmonic and the second-order LC resonance of the arm current. The module capacitance value is evaluated by focusing on the required switching dynamics and the capacitor-voltage ripple according to a newly proposed graphical method. The loading of each semiconductor in the half bridge is calculated via simulation, indicating the unsymmetrical current distribution. It is concluded that the current distribution for each semiconductor depends on the mode of operation of the converter. The different criter...

  4. Numerical simulations of the transport and diffusion during the 1991 Winter Validation Study along the Front Range in Colorado

    SciTech Connect (OSTI)

    Fast, J.D.; O'Steen, B.L.

    1992-01-01T23:59:59.000Z

    An important aspect of the US Department of Energy's Atmospheric Studies in Complex Terrain (ASCOT) program is the development and evaluation of numerical models that predict transport and diffusion of pollutants in complex terrain. Operational mesoscale modeling of the transport of pollutants in complex terrain will become increasingly practical as computational costs decrease and additional data from high-resolution remote sensing instrumentation networks become available during the 1990s. Four-dimensional data assimilation (4DDA) techniques are receiving a great deal of attention recently not only to improve the initial conditions of mesoscale forecast models, but to create high-quality four-dimensional mesoscale analysis fields that can be used as input to air-quality models. In this study, a four-dimensional data assimilation technique based on Newtonian relaxation is incorporated into the Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) and evaluated using data taken from one experiment of the 1991 ASCOT field study along the front range of the Rockies in Colorado. The main objective of this study is to compare the observed surface concentrations with those predicted by a Lagrangian particle dispersion model and to demonstrate the effect of data assimilation on the simulated plume. In contrast to pervious studies in which the smallest horizontal grid spacing was 10 km (Stauffer and Seaman, 1991) and 8 km (Yamada and Hermi, 1991), data assimilation is applied in this study to domains with a horizontal grid spacing as small as 1 km.

  5. Numerical simulations of the transport and diffusion during the 1991 Winter Validation Study along the Front Range in Colorado

    SciTech Connect (OSTI)

    Fast, J.D.; O`Steen, B.L.

    1992-11-01T23:59:59.000Z

    An important aspect of the US Department of Energy`s Atmospheric Studies in Complex Terrain (ASCOT) program is the development and evaluation of numerical models that predict transport and diffusion of pollutants in complex terrain. Operational mesoscale modeling of the transport of pollutants in complex terrain will become increasingly practical as computational costs decrease and additional data from high-resolution remote sensing instrumentation networks become available during the 1990s. Four-dimensional data assimilation (4DDA) techniques are receiving a great deal of attention recently not only to improve the initial conditions of mesoscale forecast models, but to create high-quality four-dimensional mesoscale analysis fields that can be used as input to air-quality models. In this study, a four-dimensional data assimilation technique based on Newtonian relaxation is incorporated into the Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) and evaluated using data taken from one experiment of the 1991 ASCOT field study along the front range of the Rockies in Colorado. The main objective of this study is to compare the observed surface concentrations with those predicted by a Lagrangian particle dispersion model and to demonstrate the effect of data assimilation on the simulated plume. In contrast to pervious studies in which the smallest horizontal grid spacing was 10 km (Stauffer and Seaman, 1991) and 8 km (Yamada and Hermi, 1991), data assimilation is applied in this study to domains with a horizontal grid spacing as small as 1 km.

  6. Non-filamentated ultra-intense and ultra-short pulse fronts in three-dimensional Raman seed amplification

    SciTech Connect (OSTI)

    Lehmann, G.; Spatschek, K. H. [Institut für Theoretische Physik, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf (Germany)] [Institut für Theoretische Physik, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf (Germany)

    2014-05-15T23:59:59.000Z

    Ultra-intense and ultra-short laser pulses may be generated up to the exawatt-zetawatt regime due to parametric processes in plasmas. The minimization of unwanted plasma processes leads to operational limits which are discussed here with respect to filamentation. Transverse filamentation, which originally was derived for plane waves, is being investigated for seed pulse propagation in the so called ?-pulse limit. A three-dimensional (3D) three-wave-interaction model is the basis of the present investigation. To demonstrate the applicability of the three-wave-interaction model, the 1D pulse forms are compared with those obtained from 1D particle in cell and Vlasov simulations. Although wave-breaking may occur, the kinetic simulations show that the leading pumped pulse develops a form similar to that obtained from the three-wave-interaction model. In the main part, 2D and 3D filamentation processes of (localized) pulses are investigated with the three-wave-interaction model. It is shown that the leading pulse front can stay filamentation-free, whereas the rear parts show transverse modulations.

  7. Retrofitting a 240 MWe front fired boiler for low-NOx and low UBC firing[UnBurned Carbon

    SciTech Connect (OSTI)

    Santis, R. de; Mainini, G.; Pasini, S.; Ligasacchi, S.

    1999-07-01T23:59:59.000Z

    ENEL Sulcis No.3 is a 240 MWe coal fired unit located in southern Sardinia (Italy) and originally based on a combustion system of 24 circular, radial blade burners arranged in 4 rows on the boiler front wall, fed by 6 mills. In 1992--93 a first NOx reduction project was developed, involving the burners replacement with new XCL Low-NOx burners and the installation of OFA ports; this project was subsequently canceled, mainly due to strong expected problems in UBC control. As a result of the joint Ansaldo/ENEL effort in the development of a new coal fired Low-NOx burner (TEA-C), a new project was developed and implemented in 1996--97, involving the simple replacement of the existing burners with TEA-C, the removal of Y-splitters on coal pipes and the installation of rotary classifiers on the existing mills. The unit was brought back to service, after the burners' retrofit, in late summer 1997 and the progressive installation of rotary classifiers is still ongoing; Sulcis 3 is presently operating with 3 (out of 6) rotary classifiers installed, with outstanding results (NOx {lt} 0.53 lb/MBtu, UBC {le} 7% burning South American, low ash coals). The paper provides an overview on the design choices and describes the results obtained by field testing the newly installed Low-NOx combustions system.

  8. Local attitudes, knowledge and values regarding natural resource use in the range of the Maroon-fronted Parrot in northeastern Mexico

    E-Print Network [OSTI]

    Madero-Farias, Alma Alida

    2000-01-01T23:59:59.000Z

    of the Maroon-Fronted Parrot in Northeastern Mexico. (August 2000) Alma Alida Madero-Farias, I. A. Z, , Instituto Tecnologico y de Estudios Superiores de Monterrey, Mexico. Chair of Advisory Committee: Dr. Jane M. Packard New ecosystem management policies... while studying. That allowed me to finish my degree and to fund this project. From the Instituto Tecnologico y de Estudios Superiores de Monterrey, I am grateful to Dr. Irma Gomez from the Graduate School in Administration and Business Management...

  9. Wheels of Darkness and Other Stories

    E-Print Network [OSTI]

    Roy, E.; Kurz, R.

    rested, eyes open, watching his lover sleep. Sandy's arm lay next to his. Long, slim, tanned flesh. Young flesh. His arm looked tired next to that one. Skin paler, sagging, a little grey. Old. A scuffling sound came from the door. Richard turned his... eyes flashed at him. "Where? In the apartment, or in your life?" "Whichever." Richard felt old, locking the scrapbook away. He felt tired. "Look. We had some good times ... " He couldn't finish that cliche either. He dropped his head, massaging his...

  10. Qualifying Facility Wheeling Task Force-- Status Report

    E-Print Network [OSTI]

    Panjavan, S.

    . P.O. Box 1188 Houston, TX 77001 Mr. Dan Hill Coastal Refining Company Nine Greenway Plaza Houston, TX 77046 PUCT ELECTRIC DIVISION STAFF MEMBERS 7800 Shoal Creek Blvd., Suite 400n Austin, TX 78757 Mr. Hal Hughes, Manager of Engineering...

  11. Bradbury Science Museum - Science on Wheels

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccess Stories Site MapSolarAbout Neutrinos2.769 2.813Bradbury

  12. THE PROJECT-X INJECTOR EXPERIMENT: A NOVEL HIGH PERFORMANCE FRONT-END FOR A FUTURE HIGH POWER PROTON FACILITY AT FERMILAB

    SciTech Connect (OSTI)

    Nagaitsev, S.; et al,

    2013-09-25T23:59:59.000Z

    A multi-MW proton facility, Project X, has been proposed and is currently under development at Fermilab. We are carrying out a program of research and development aimed at integrated systems testing of critical components comprising the front end of Project X. This program, known as the Project X Injector Experiment (PXIE), is being undertaken as a key component of the larger Project X R&D program. The successful completion of this program will validate the concept for the Project X front end, thereby minimizing a primary technical risk element within Project X. PXIE is currently under construction at Fermilab and will be completed over the period FY12-17. PXIE will include an H* ion source, a CW 2.1-MeV RFQ and two superconductive RF (SRF) cryomodules providing up to 25 MeV energy gain at an average beam current of 1 mA (upgradable to 2 mA). Successful systems testing will also demonstrate the viability of novel front end technologies that are expected find applications beyond Project X.

  13. TRENDS in Genetics Vol.18 No.11 November 2002 http://tig.trends.com 0168-9525/02/$ see front matter 2002 Elsevier Science Ltd. All rights reserved. PII

    E-Print Network [OSTI]

    Fernandez, Thomas

    matter © 2002 Elsevier Science Ltd. All rights reserved. PII: 555Opinion One result of genome-9525/02/$ ­ see front matter © 2002 Elsevier Science Ltd. All rights reserved. PII: S0168-9525(02)02765-8 Genotype

  14. FrontMatter.qxd

    Broader source: Energy.gov (indexed) [DOE]

    A PRACTICAL "HOW TO" GUIDE FOR THE NATIONAL PARK SERVICE VISITOR CENTERS A PRODUCT OF THE GREEN ENERGY PARKS PARTNERSHIP NATIONAL PARK SERVICE * DEPARTMENT OF ENERGY Prepared by...

  15. New Vision front

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForumEngines |New Technology forDepartment of

  16. cover front.qxd

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently20,000 Russian Nuclear Warheads|ofEventsWorkshopY-12a Multi-User NetworkColdOFFICE

  17. Discourse on Cabin 3

    E-Print Network [OSTI]

    Weiner, Seth, 1976-

    2002-01-01T23:59:59.000Z

    An adaptation of the Unabomber's cabin placed on four automobile wheels, Cabin 3 was installed as a hybrid cabin-vehicle-writing device on the elevated plaza in front of 105 Massachusetts Ave on MIT's campus. Inside the ...

  18. Modeling an automobile steering system using Axiomatic Design's Design Matrix and the Design Structure Matrix

    E-Print Network [OSTI]

    Bagley, Matthew R., 1966-

    2005-01-01T23:59:59.000Z

    The automobile steering system can be thought of as a system within a system. The steering system has clear functions and requirements as well as many interrelated components and subsystems including the front tires, wheels, ...

  19. LARGE-SCALE CORONAL PROPAGATING FRONTS IN SOLAR ERUPTIONS AS OBSERVED BY THE ATMOSPHERIC IMAGING ASSEMBLY ON BOARD THE SOLAR DYNAMICS OBSERVATORY—AN ENSEMBLE STUDY

    SciTech Connect (OSTI)

    Nitta, Nariaki V.; Schrijver, Carolus J.; Title, Alan M.; Liu, Wei [Lockheed Martin Advanced Technology Center, Dept/A021S, B/252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

    2013-10-10T23:59:59.000Z

    This paper presents a study of a large sample of global disturbances in the solar corona with characteristic propagating fronts as intensity enhancement, similar to the phenomena that have often been referred to as Extreme Ultraviolet Imaging Telescope (EIT) waves or extreme-ultraviolet (EUV) waves. Now EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory provide a significantly improved view of these large-scale coronal propagating fronts (LCPFs). Between 2010 April and 2013 January, a total of 171 LCPFs have been identified through visual inspection of AIA images in the 193 Å channel. Here we focus on the 138 LCPFs that are seen to propagate across the solar disk, first studying how they are associated with flares, coronal mass ejections (CMEs), and type II radio bursts. We measure the speed of the LCPF in various directions until it is clearly altered by active regions or coronal holes. The highest speed is extracted for each LCPF. It is often considerably higher than EIT waves. We do not find a pattern where faster LCPFs decelerate and slow LCPFs accelerate. Furthermore, the speeds are not strongly correlated with the flare intensity or CME magnitude, nor do they show an association with type II bursts. We do not find a good correlation either between the speeds of LCPFs and CMEs in a subset of 86 LCPFs observed by one or both of the Solar and Terrestrial Relations Observatory spacecraft as limb events.

  20. Variational Analysis of Mass Spectra and Decay Constants for Ground State Pseudoscalar and Vector Mesons in Light-Front Quark Model

    E-Print Network [OSTI]

    Choi, Ho-Meoyng; Li, Ziyue

    2015-01-01T23:59:59.000Z

    Using the variational principle, we compute mass spectra and decay constants of ground state pseudoscalar and vector mesons in the light-front quark model with the QCD-motivated effective Hamiltonian including the hyperfine interaction. By smearing out the Dirac delta function in the hyperfine interaction, we avoid the issue of negative infinity in applying the variational principle to the computation of meson mass spectra. In comparison with the previous computation handling the hyperfine interaction as perturbation, our variational analysis provides an overall improvement on the agreement with the experimental data of mass spectra for the ground state pseudoscalar and vector mesons from $\\pi$ to $\\Upsilon$. By taking a larger harmonic oscillator basis in our trial wave function, we also obtain the better agreement between the experimental data of decay constants and the results from our model calculation for these mesons.