Sample records for high compression ratio

  1. High Compression Ratio Turbo Gasoline Engine Operation Using...

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

    Compression Ratio Turbo Gasoline Engine Operation Using Alcohol Enhancement PI: John B. Heywood Sloan Automotive Laboratory Massachusetts Institute of Technology June 19, 2014...

  2. Particle acceleration in thick parallel shocks with high compression ratio

    E-Print Network [OSTI]

    Joni J. P. Virtanen; Rami Vainio

    2005-06-06T23:59:59.000Z

    We report studies on first-order Fermi acceleration in parallel modified shock waves with a large scattering center compression ratio expected from turbulence transmission models. Using a Monte Carlo technique we have modeled particle acceleration in shocks with a velocity ranging from nonrelativistic to ultrarelativistic and a thickness extending from nearly steplike to very wide structures exceeding the particle diffusion length by orders of magnitude. The nonrelativistic diffusion approximation is found to be surprisingly accurate in predicting the spectral index of a thick shock with large compression ratio even in the cases involving relativistic shock speeds.

  3. High compression ratio turbo gasoline engine operation using alcohol enhancement

    E-Print Network [OSTI]

    Lewis, Raymond (Raymond A.)

    2013-01-01T23:59:59.000Z

    Gasoline - ethanol blends were explored as a strategy to mitigate engine knock, a phenomena in spark ignition engine combustion when a portion of the end gas is compressed to the point of spontaneous auto-ignition. This ...

  4. Envera Variable Compression Ratio Engine

    SciTech Connect (OSTI)

    Charles Mendler

    2011-03-15T23:59:59.000Z

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

  5. Eccentric crank variable compression ratio mechanism

    DOE Patents [OSTI]

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

    2008-05-13T23:59:59.000Z

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

  6. Vehicle Technologies Office Merit Review 2014: High Compression Ratio Turbo Gasoline Engine Operation Using Alcohol Enhancement

    Broader source: Energy.gov [DOE]

    Presentation given by Massachusetts Institute of Technology at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high...

  7. Vehicle Technologies Office Merit Review 2014: High Compression...

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

    High Compression Ratio Turbo Gasoline Engine Operation Using Alcohol Enhancement Vehicle Technologies Office Merit Review 2014: High Compression Ratio Turbo Gasoline Engine...

  8. Prediction-Based Compression Ratio Boundaries for Medical Images

    E-Print Network [OSTI]

    Qi, Xiaojun

    Prediction-Based Compression Ratio Boundaries for Medical Images Xiaojun Qi Computer Science present prediction-based image compression techniques take advantage of either intra- or inter function. The prediction-based compression technique has been applied on some magnetic resonance (MR) brain

  9. Benefits and Drawbacks of Compression Ratio Reduction in PCCI...

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

    effect of compression ratio on performance of light duty diesel operating with PCCI calibration, near EURO6Tier 2 Bin 5 NOx limits. deer08beatrice.pdf More Documents &...

  10. High efficiency coarse-grained customised dynamically reconfigurable architecture for digital image processing and compression technologies 

    E-Print Network [OSTI]

    Zhao, Xin

    2012-06-25T23:59:59.000Z

    Digital image processing and compression technologies have significant market potential, especially the JPEG2000 standard which offers outstanding codestream flexibility and high compression ratio. Strong demand for ...

  11. High Efficiency Fuel Reactivity Controlled Compression Ignition...

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

    & Publications Effect of Compression Ratio and Piston Geometry on RCCI load limit Optimization of Advanced Diesel Engine Combustion Strategies Vehicle Technologies Office Merit...

  12. High ratio recirculating gas compressor

    DOE Patents [OSTI]

    Weinbrecht, J.F.

    1989-08-22T23:59:59.000Z

    A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

  13. Effects of operating conditions, compression ratio, and gasoline reformate on SI engine knock limits

    E-Print Network [OSTI]

    Gerty, Michael D

    2005-01-01T23:59:59.000Z

    A set of experiments was performed to investigate the effects of air-fuel ratio, inlet boost pressure, hydrogen rich fuel reformate, and compression ratio on engine knock behavior. For each condition the effect of spark ...

  14. Advanced CFD Models for High Efficiency Compression Ignition...

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

    CFD Models for High Efficiency Compression Ignition Engines Advanced CFD Models for High Efficiency Compression Ignition Engines Advanced CFD models for high efficiency...

  15. High-Pressure Micellar Solutions of Symmetric and Asymmetric Styrene?Diene Diblocks in Compressible Near Critical Solvents: Micellization Pressures and Cloud Pressures Respond but Micellar Cloud Pressures Insensitive to Copolymer Molecular Weight, Concentration, and Block Ratio Changes

    SciTech Connect (OSTI)

    Winoto, Winoto [University of Wyoming, Laramie; Tan, Sugata [University of Wyoming, Laramie; Shen, Youqin [University of Wyoming, Laramie; Radosz, Maciej [University of Wyoming, Laramie; Hong, Kunlun [ORNL; Mays, Jimmy [ORNL

    2009-01-01T23:59:59.000Z

    Micellar solutions of polystyrene-block-polybutadiene and polystyrene-block-polyisoprene in propane are found to exhibit significantly lower cloud pressures than the corresponding hypothetical nonmicellar solutions. Such a cloud-pressure reduction indicates the extent to which micelle formation enhances the apparent diblock solubility in near-critical and hence compressible propane. Concentration-dependent pressure-temperature points beyond which no micelles can be formed, referred to as the micellization end points, are found to depend on the block type, size, and ratio. The cloud-pressure reduction and the micellization end point measured for styrene-diene diblocks in propane should be characteristic of all amphiphilic diblock copolymer solutions that form micelles in compressible solvents.

  16. High-Efficiency Clean Combustion Engine Designs for Compression...

    Energy Savers [EERE]

    High-Efficiency Clean Combustion Engine Designs for Compression Ignition Engines High-Efficiency Clean Combustion Engine Designs for Compression Ignition Engines Presentation from...

  17. High-Efficiency Clean Combustion Design for Compression Ignition...

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

    High-Efficiency Clean Combustion Design for Compression Ignition Engines High-Efficiency Clean Combustion Design for Compression Ignition Engines Presentation given at DEER 2006,...

  18. High Fidelity Modeling of Premixed Charge Compression Ignition...

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

    Fidelity Modeling of Premixed Charge Compression Ignition Engines High Fidelity Modeling of Premixed Charge Compression Ignition Engines Most accurate and detailed chemical kinetic...

  19. High load operation in a homogeneous charge compression ignition engine

    DOE Patents [OSTI]

    Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Liechty, Michael P. (Chillicothe, IL); Hardy, William L. (Peoria, IL); Rodman, Anthony (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL)

    2008-12-23T23:59:59.000Z

    A homogeneous charge compression ignition engine is set up by first identifying combinations of compression ratio and exhaust gas percentages for each speed and load across the engines operating range. These identified ratios and exhaust gas percentages can then be converted into geometric compression ratio controller settings and exhaust gas recirculation rate controller settings that are mapped against speed and load, and made available to the electronic

  20. Some investigations in design of low cost variable compression ratio two stroke petrol engine

    E-Print Network [OSTI]

    Srinivas, A; rao, P Venkateswar; Reddy, M Penchal

    2012-01-01T23:59:59.000Z

    Historically two stroke engine petrol engines find wide applications in construction of two wheelers worldwide, however due to stringent environmental laws enforced universally; these engines are fading in numbers. In spite of the tight norms, internationally these engines are still used in agriculture, gensets etc. Several designs of variable compression ratio two stroke engines are commercially available for analysis purpose. In this present investigation a novel method of changing the compression ratio is proposed, applied, studied and analyzed. The clearance volume of the engine is altered by introducing a metal plug into the combustion chamber. This modification permitted to have four different values of clearance value keeping in view of the studies required the work is brought out as two sections. The first part deals with the design, modification, engine fabrication and testing at different compression ratios for the study of performance of the engine. The second part deals with the combustion in engi...

  1. Hydrodynamic compressibility of high-strength ceramics

    SciTech Connect (OSTI)

    Grady, D.E.

    1993-08-01T23:59:59.000Z

    In this study we have developed the techniques to investigate the hydrodynamic response of high-strength ceramics by mixing these powders with copper powder, preparing compacts, and performing shock compression tests on these mixtures. Hydrodynamics properties of silicon carbide, titanium diboride, and boron carbide to 30 GPa were examined by this method, and hydrodynamic compression data for these ceramics have been determined. We have concluded, however, that the measurement method is sensitive to sample preparation and uncertainties in shock wave measurements. Application of the experimental technique is difficult and further efforts are needed.

  2. The Effects of Fuel Composition and Compression Ratio on Thermal Efficiency in an HCCI Engine

    SciTech Connect (OSTI)

    Szybist, James P [ORNL; Bunting, Bruce G [ORNL

    2007-01-01T23:59:59.000Z

    The effects of variable compression ratio (CR) and fuel composition on thermal efficiency were investigated in a homogeneous charge compression ignition (HCCI) engine using blends of n-heptane and toluene with research octane numbers (RON) of 0 to 88. Experiments were conducted by performing CR sweeps at multiple intake temperatures using both unthrottled operation, and constant equivalence ratio conditions by throttling to compensate for varying air density. It was found that CR is effective at changing and controlling HCCI combustion phasing midpoint, denoted here as CA 50. Thermal efficiency was a strong function of CA 50, with overly advanced CA 50 leading to efficiency decreases. Increases in CR at a constant CA 50 for a given fuel composition did, in most cases, increase efficiency, but the relationship was weaker than the dependence of efficiency on CA 50. The increase in efficiency with higher CR was fuel-dependent, so that the fuels requiring a higher CR to achieve ignition did not gain a proportionate efficiency increase. For example, n-heptane achieved an indicated thermal efficiency (ITE) of 38% at a CR of 9:1, whereas a 50 wt% blend of toluene with n-heptane required a CR of 12:1 to achieve the same ITE. A simple heat balance around the engine showed that higher toluene content fuels had higher cooling losses. The high toluene fuels exhibited higher rates of maximum pressure rise than the lower octane fuels. The increased cooling losses can be attributed to the higher pressure rise rates, which are a driving force for heat transfer.

  3. The relation of octane number, compression ratio, and exhaust temperature in the gasoline engine

    E-Print Network [OSTI]

    Jentsch, Donald George

    1951-01-01T23:59:59.000Z

    of this effect was aided by the use of two test engines, one a single cylinder variable compression ratio experimental engine, and the other a standard industrial V-8 automotive engine. The follosing discussion is given to define "fuel octane ratings...", by C. D. Hiller p S. A. E. Transactions, Vol. 1, No. 19 January 19479 pp. 98. 24. "Evaluating Fuels for &igh Compression Engines", by N. Roensch and J. C. Hughes, Automotive Industries, November 1, 1950, pp. 50. THE RELATION OF OCTANE NM3ER...

  4. High Transformer ratios in collinear wakefield accelerators.

    SciTech Connect (OSTI)

    Power, J. G.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanreykin, A.; Schoessow, P.; High Energy Physics; Euclid Techlabs, LLC

    2008-01-01T23:59:59.000Z

    Based on our previous experiment that successfully demonstrated wakefield transformer ratio enhancement in a 13.625 GHz dielectric-loaded collinear wakefield accelerator using the ramped bunch train technique, we present here a redesigned experimental scheme for even higher enhancement of the efficiency of this accelerator. Design of a collinear wakefield device with a transformer ratio R2, is presented. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2. To match the wavelength of the fundamental mode of the wakefield with the bunch length (sigmaz=2 mm) of the new Argonne wakefield accelerator (AWA) drive gun (where the experiment will be performed), a 26.625 GHz dielectric based accelerating structure is required. This transformer ratio enhancement technique based on our dielectric-loaded waveguide design will result in a compact, high efficiency accelerating structures for future wakefield accelerators.

  5. High-Efficiency Clean Combustion Engine Designs for Compression...

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

    Russ Durrett For Public Release GM R&D - Diesel Engine Systems High-Efficiency Clean Combustion Engine Designs for Compression Ignition Engines Russ Durrett, Xin He - General...

  6. Mesoscale flows in large aspect ratio simulations of turbulent compressible convection

    E-Print Network [OSTI]

    F. Rincon; F. Lignieres; M. Rieutord

    2006-11-28T23:59:59.000Z

    We present the results of a very large aspect ratio (42.6) numerical simulation of fully compressible turbulent convection in a polytropic atmosphere, and focus on the properties of large-scale flows. Mesoscale patterns dominate the turbulent energy spectrum. We show that these structures, which had already been observed in Boussinesq simulations by Cattaneo et al. (2001), have a genuine convective origin and do not result directly from collective interactions of the smaller scales of the flow, even though their growth is strongly affected by nonlinear transfers. If this result is relevant to the solar photosphere, it suggests that the dominant convective mode below the Sun's surface may be at mesoscales.

  7. High aspect ratio, remote controlled pumping assembly

    DOE Patents [OSTI]

    Brown, Steve B. (Livermore, CA); Milanovich, Fred P. (Lafayette, CA)

    1995-01-01T23:59:59.000Z

    A miniature dual syringe-type pump assembly which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor.

  8. High aspect ratio, remote controlled pumping assembly

    DOE Patents [OSTI]

    Brown, S.B.; Milanovich, F.P.

    1995-11-14T23:59:59.000Z

    A miniature dual syringe-type pump assembly is described which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor. 4 figs.

  9. Computation of Weakly-Compressible Highly-Viscous Polymeric Liquid Flows

    E-Print Network [OSTI]

    Grant, P. W.

    such circumstances, the speed of sound is much larger than the velocity of the liquid, resulting in fast pressure, the ratio of fluid velocity to the speed of sound ( cuMa /= ), characterises the influence1 Computation of Weakly-Compressible Highly-Viscous Polymeric Liquid Flows M. F. Webster 1*, I. J

  10. Compressive Sensing Based High Resolution Channel Estimation ...

    E-Print Network [OSTI]

    2011-09-17T23:59:59.000Z

    arbitrary index set ? of cardinality M and discards the rest, and .... Lemma 2: For any given index set T with |T| = Scompression ratio of 16.

  11. High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback

    SciTech Connect (OSTI)

    Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

    2007-12-31T23:59:59.000Z

    This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when they are opened. As a result of this effort, we have devised a new design and have filed for a patent on a method of control which is believed to overcome this problem. The engine we have been working with originally had a single camshaft which controlled both the intake and exhaust valves. Single cycle lift and timing control was demonstrated with this system. (3) Large eddy simulations and KIVA based simulations were used in conjunction with flow visualizations in an optical engine to study fuel air mixing. During this effort we have devised a metric for quantifying fuel distribution and it is described in several of our papers. (4) A control system has been developed to enable us to test the benefits of the various technologies. This system used is based on Opal-RT hardware and is being used in a current DOE sponsored program.

  12. A compression scheme for radio data in high performance computing

    E-Print Network [OSTI]

    Masui, Kiyoshi; Connor, Liam; Deng, Meiling; Fandino, Mateus; Höfer, Carolin; Halpern, Mark; Hanna, David; Hincks, Adam D; Hinshaw, Gary; Parra, Juan Mena; Newburgh, Laura B; Shaw, J Richard; Vanderlinde, Keith

    2015-01-01T23:59:59.000Z

    We present a procedure for efficiently compressing astronomical radio data for high performance applications. Integrated, post-correlation data are first passed through a nearly lossless rounding step which compares the precision of the data to a generalized and calibration-independent form of the radiometer equation. This allows the precision of the data to be reduced in a way that has an insignificant impact on the data. The newly developed Bitshuffle lossless compression algorithm is subsequently applied. When the algorithm is used in conjunction with the HDF5 library and data format, data produced by the CHIME Pathfinder telescope is compressed to 28% of its original size and decompression throughputs in excess of 1 GB/s are obtained on a single core.

  13. Active high-power RF switch and pulse compression system

    DOE Patents [OSTI]

    Tantawi, Sami G. (San Mateo, CA); Ruth, Ronald D. (Woodside, CA); Zolotorev, Max (Mountain View, CA)

    1998-01-01T23:59:59.000Z

    A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power. The switch is useful to the construction of an improved pulse compression system to boost the peak power of microwave tubes driving linear accelerators. In this application, the high-power RF switch is placed at the coupling iris between the charging waveguide and the resonant storage line of a pulse compression system. This optically controlled high power RF pulse compression system can handle hundreds of Megawatts of power at X-band.

  14. Rapid Replication of High Aspect Ratio Molds for UV Embossing

    E-Print Network [OSTI]

    Yan, Yehai

    This paper describes a promising fabrication technique for rapid replication of high aspect ratio microstructured molds for UV embossing. The process involves casting silicone rubber on a microstructured master, replicating ...

  15. Mechanical Compression Heat Pumps 

    E-Print Network [OSTI]

    Apaloo, T. L.; Kawamura, K.; Matsuda, J.

    1986-01-01T23:59:59.000Z

    to develop, design and test compressors built to meet the needs of the mechanically demanding industrial heat pump applications which often require high compression ratios and temperatures in excess of 200 degrees F. This paper will review the theoretical...

  16. System and method for high precision isotope ratio destructive analysis

    DOE Patents [OSTI]

    Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

    2013-07-02T23:59:59.000Z

    A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

  17. ITER physics design guidelines at high aspect ratio

    SciTech Connect (OSTI)

    Uckan, N.A.

    1991-01-01T23:59:59.000Z

    The physics requirements for ITER design are formulated in a set of physics design guidelines. These guidelines, established by the ITER Physics Group during the Conceptual Design Activity (CDA, 1988--90), were based on credible extrapolations of the tokamak physics database as assessed during the CDA, and defined a class of tokamak designs (with plasma current I {approximately}20 MA and aspect ratio A {approximately}2.5--3.5) that meet the ITER objectives. Recent US studies have indicated that there may be significant benefits if the ITER-CDA design point is moved from the low aspect ratio, high current baseline (A = 2.79, I = 22 MA) to a high aspect ratio machine at A {approximately}4, I {approximately}15 MA, especially regarding steady-state, technology-testing performance. To adequately assess the physics and technology testing capability of higher aspect ratio design options, several changes are proposed to the original ITER guidelines to reflect the latest (although limited) developments in physics understanding at higher aspect ratios. The critical issues for higher aspect ratio design options are the uncertainty in scaling of confinement with aspect ratio, the variation of vertical stability with elongation and aspect ratio, plasma shaping requirements, ability to control and maintain plasma current and q-profiles for MHD stability (and volt-second consumption), access for current drive, restrictions on field ripple and divertor plate incident angles, etc. 5 refs., 1 tab.

  18. Validation of a blowby model using experimental results in motoring condition with the change of compression ratio and engine speed

    SciTech Connect (OSTI)

    Aghdam, E. Abdi [Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil (Iran); Kabir, M.M. [Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil (Iran); Department of Engineering, Islamic Azad University, Aliabad Katoul Branch, Golestan (Iran)

    2010-02-15T23:59:59.000Z

    Blowby and gas flow through the cylinder-piston-ring crevices are phenomena that affect the engine performance and exhaust emissions. Also these phenomena influence the cylinder pressure and temperature and the charge amount during a cycle. The study and validation of a sub-model for these phenomena in the absence of engine combustion deducts all effects arisen from the combustion event. During the current study, blowby sub-model and gas flow through crevices under motoring conditions has been noticed using a volume-orifice theory and the experimental results measured from a research engine. Blowby geometric parameters, consisting of a few critical cross-section areas (orifice areas) and volumes (top land and inter-ring crevice volumes), were measured in ambient temperature and corrected for hot running conditions. The cylinder pressure during cycle was measured by a piezoelectric pressure transducer and the low pressure parts of the cycle were measured using a piezoresistive pressure transducer for referencing purposes. The obtained results show a very good agreement between experimentally measured pressure data and model output for three compression ratios of 7.6, 10.2, 12.4 and three engine speeds of 750, 1500 and 2000 rpm, so that the maximum deviation was almost 5%. The model predicted that the maximum mass loss increased with increase of compression ratio and decreased with increase of engine speed. Also the peak mass loss position happened within the range of 3-9 CA after top dead center. After occurrence of the maximum loss, a reverse flow from the top land crevice into the cylinder was predicted in the model. (author)

  19. The Use of Fuel Chemistry and Property Variations to Evaluate the Robustness of Variable Compression Ratio as a Control Method for Gasoline HCCI

    SciTech Connect (OSTI)

    Szybist, James P [ORNL; Bunting, Bruce G [ORNL

    2007-01-01T23:59:59.000Z

    On a gasoline engine platform, homogeneous charge compression ignition (HCCI) holds the promise of improved fuel economy and greatly reduced engine-out NOx emissions, without an increase in particulate matter emissions. In this investigation, a variable compression ratio (CR) engine equipped with a throttle and intake air heating was used to test the robustness of these control parameters to accommodate a series of fuels blended from reference gasoline, straight run refinery naptha, and ethanol. Higher compression ratios allowed for operation with higher octane fuels, but operation could not be achieved with the reference gasoline, even at the highest compression ratio. Compression ratio and intake heat could be used separately or together to modulate combustion. A lambda of 2 provided optimum fuel efficiency, even though some throttling was necessary to achieve this condition. Ethanol did not appear to assist combustion, although only two ethanol-containing fuels were evaluated. The increased pumping work from throttling was minimal compared to the efficiency increases that were the result of lower unburned hydrocarbon (HC) and carbon monoxide (CO) emissions. Low temperature heat release was present for all the fuels, but could be suppressed with a higher intake air temperature. Results will be used to design future fuels and combustion studies with this research platform.

  20. Multilayer compressive seal for sealing in high temperature devices

    DOE Patents [OSTI]

    Chou, Yeong-Shyung (Richland, WA); Stevenson, Jeffry W. (Richland, WA)

    2007-08-21T23:59:59.000Z

    A mica based compressive seal has been developed exhibiting superior thermal cycle stability when compared to other compressive seals known in the art. The seal is composed of compliant glass or metal interlayers and a sealing (gasket) member layer composed of mica that is infiltrated with a glass forming material, which effectively reduces leaks within the seal. The compressive seal shows approximately a 100-fold reduction in leak rates compared with previously developed hybrid seals after from 10 to about 40 thermal cycles under a compressive stress of from 50 psi to 100 psi at temperatures in the range from 600.degree. C. to about 850.degree. C.

  1. Control of high power pulse extracted from the maximally compressed pulse in a nonlinear optical fiber

    E-Print Network [OSTI]

    Yang, Guangye; Jia, Suotang; Mihalache, Dumitru

    2013-01-01T23:59:59.000Z

    We address the possibility to control high power pulses extracted from the maximally compressed pulse in a nonlinear optical fiber by adjusting the initial excitation parameters. The numerical results show that the power, location and splitting order number of the maximally compressed pulse and the transmission features of high power pulses extracted from the maximally compressed pulse can be manipulated through adjusting the modulation amplitude, width, and phase of the initial Gaussian-type perturbation pulse on a continuous wave background.

  2. The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems

    SciTech Connect (OSTI)

    Guo, Jiquan; /SLAC

    2009-03-20T23:59:59.000Z

    In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of this novel mode-converter. We demonstrate an electrically controlled ultra-fast high power X-band RF active window built with PIN diodes on high resistivity silicon. The window is capable of handling multi-megawatt RF power and can switch in 2-300ns with a 1000A current driver. A low power active pulse compression experiment was carried out with the switch module and a 375ns resonant delay line, obtaining 8 times compression gain with a compression ratio of 20.

  3. Homogenous charge compression ignition engine having a cylinder including a high compression space

    DOE Patents [OSTI]

    Agama, Jorge R.; Fiveland, Scott B.; Maloney, Ronald P.; Faletti, James J.; Clarke, John M.

    2003-12-30T23:59:59.000Z

    The present invention relates generally to the field of homogeneous charge compression engines. In these engines, fuel is injected upstream or directly into the cylinder when the power piston is relatively close to its bottom dead center position. The fuel mixes with air in the cylinder as the power piston advances to create a relatively lean homogeneous mixture that preferably ignites when the power piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. Thus, the present invention divides the homogeneous charge between a controlled volume higher compression space and a lower compression space to better control the start of ignition.

  4. A high-resolution mapped grid algorithm for compressible multiphase flow problems

    E-Print Network [OSTI]

    Shyue, Keh-Ming

    A high-resolution mapped grid algorithm for compressible multiphase flow problems K.-M. Shyue mapped grid approach for the efficient numerical simula- tion of compressible multiphase flow in general problems, J. Comput. Phys. 142 (1998) 208-242). A standard high-resolution mapped grid method in wave

  5. Compressing magnetic fields with high-energy lasersa... J. P. Knauer,1,b

    E-Print Network [OSTI]

    Compressing magnetic fields with high-energy lasersa... J. P. Knauer,1,b O. V. Gotchev,1,2,3 P. Y, Rochester, New York 14623, USA 3 Department of Mechanical Engineering, University of Rochester, 250 East-driven magnetic-field compression producing a magnetic field of tens of megaGauss is reported for the first time

  6. A high-resolution mapped grid algorithm for compressible multiphase flow problems

    E-Print Network [OSTI]

    Shyue, Keh-Ming

    A high-resolution mapped grid algorithm for compressible multiphase flow problems K.-M. Shyue 18 August 2010 Keywords: Compressible multiphase flow Fluid-mixture model Mapped grids Wave-propagation method Stiffened gas equation of state a b s t r a c t We describe a simple mapped-grid approach

  7. Proof-of-Concept Manufacturing and Testing of Composite Wind Generator Blades Made by HCBMP (High Compression Bladder Molded Prepreg)

    SciTech Connect (OSTI)

    William C. Leighty; DOE Project Officer - Keith Bennett

    2005-10-04T23:59:59.000Z

    Proof-of-Concept Manufacturing and Testing of Composite Wind Generator Blades Made by HCBMP (High Compression Bladder Molded Prepreg)

  8. High Efficiency, Low Emissions Homogeneous Charge Compression Ignition (HCCI) Engines

    SciTech Connect (OSTI)

    None

    2011-01-31T23:59:59.000Z

    This is the final report of the High Efficiency Clean Combustion (HECC) Research Program for the U.S. Department of Energy. Work under this co-funded program began in August 2005 and finished in July 2010. The objective of this program was to develop and demonstrate a low emission, high thermal efficiency engine system that met 2010 EPA heavy-duty on-highway truck emissions requirements (0.2g/bhp-hr NOx, 0.14g/bhp-hr HC and 0.01g/bhp-hr PM) with a thermal efficiency of 46%. To achieve this goal, development of diesel homogenous charge compression ignition (HCCI) combustion was the chosen approach. This report summarizes the development of diesel HCCI combustion and associated enabling technologies that occurred during the HECC program between August 2005 and July 2010. This program showed that although diesel HCCI with conventional US diesel fuel was not a feasible means to achieve the program objectives, the HCCI load range could be increased with a higher volatility, lower cetane number fuel, such as gasoline, if the combustion rate could be moderated to avoid excessive cylinder pressure rise rates. Given the potential efficiency and emissions benefits, continued research of combustion with low cetane number fuels and the effects of fuel distillation are recommended. The operation of diesel HCCI was only feasible at part-load due to a limited fuel injection window. A 4% fuel consumption benefit versus conventional, low-temperature combustion was realized over the achievable operating range. Several enabling technologies were developed under this program that also benefited non-HCCI combustion. The development of a 300MPa fuel injector enabled the development of extended lifted flame combustion. A design methodology for minimizing the heat transfer to jacket water, known as precision cooling, will benefit conventional combustion engines, as well as HCCI engines. An advanced combustion control system based on cylinder pressure measurements was developed. A Well-to-wheels analysis of the energy flows in a mobile vehicle system and a 2nd Law thermodynamic analysis of the engine system were also completed under this program.

  9. A Natural Gas, High Compression Ratio, High Efficiency ICRE | Department of

    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 Your Destiny: The Future of BadTHEEnergyReliability2015GrossA FewAJanuary 2014and

  10. Characterization Of High-Stroke High-Aspect Ratio Micro Electro Mechanical Systems Deformable Mirrors For Adaptive Optics

    E-Print Network [OSTI]

    Bouchti, Mohamed Amine

    2013-01-01T23:59:59.000Z

    Journal of Microelectromechanical Systems 8, 497– 8)High-aspect ratio microelectromechanical systems deformable

  11. Modeling and Analysis of Natural Gas and Gasoline In A High Compressio...

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

    and Analysis of Natural Gas and Gasoline In A High Compression Ratio High Efficiency ICRE Modeling and Analysis of Natural Gas and Gasoline In A High Compression Ratio High...

  12. High transformer ratio drive beams for wakefield accelerator studies

    SciTech Connect (OSTI)

    England, R. J.; Ng, C.-K.; Frederico, J.; Hogan, M. J.; Litos, M.; Muggli, P.; Joshi, C.; An, W.; Andonian, G.; Mori, W.; Lu, W. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Max Planck Institute for Physics, 80805 Munich (Germany); University of California Los Angeles, Los Angeles, CA 90095 (United States); Tsinghua University, Beijing (China)

    2012-12-21T23:59:59.000Z

    For wakefield based acceleration schemes, use of an asymmetric (or linearly ramped) drive bunch current profile has been predicted to enhance the transformer ratio and generate large accelerating wakes. We discuss plans and initial results for producing such bunches using the 20 to 23 GeV electron beam at the FACET facility at SLAC National Accelerator Laboratory and sending them through plasmas and dielectric tubes to generate transformer ratios greater than 2 (the limit for symmetric bunches). The scheme proposed utilizes the final FACET chicane compressor and transverse collimation to shape the longitudinal phase space of the beam.

  13. Dynamics of Homogeneous Charge Compression Ignition (HCCI) Engines with High Dilution

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Dynamics of Homogeneous Charge Compression Ignition (HCCI) Engines with High Dilution C. J. Chiang (HCCI) engines in light of the cycle-to-cycle thermal feedback due to the high percentage of exhaust temperature is the primary mechanism for con- trolling ignition timing in an HCCI engine, especially when

  14. Gyrokinetic Particle Simulation of Compressible Electromagnetic Turbulence in High-? Plasmas

    SciTech Connect (OSTI)

    Lin, Zhihong

    2014-03-13T23:59:59.000Z

    Supported by this award, the PI and his research group at the University of California, Irvine (UCI) have carried out computational and theoretical studies of instability, turbulence, and transport in laboratory and space plasmas. Several massively parallel, gyrokinetic particle simulation codes have been developed to study electromagnetic turbulence in space and laboratory plasmas. In space plasma projects, the simulation codes have been successfully applied to study the spectral cascade and plasma heating in kinetic Alfven wave turbulence, the linear and nonlinear properties of compressible modes including mirror instability and drift compressional mode, and the stability of the current sheet instabilities with finite guide field in the context of collisionless magnetic reconnection. The research results have been published in 25 journal papers and presented at many national and international conferences. Reprints of publications, source codes, and other research-related information are also available to general public on the PI’s webpage (http://phoenix.ps.uci.edu/zlin/). Two PhD theses in space plasma physics are highlighted in this report.

  15. Post-compression of high energy terawatt-level femtosecond pulses and application to high order harmonic generation

    E-Print Network [OSTI]

    Hort, Ond?ej; Cabasse, Amélie; Petit, Stéphane; Mével, Eric; Descamps, Dominique; Constant, Eric

    2015-01-01T23:59:59.000Z

    We perform a post-compression of high energy pulses by using optical-field ionization of low pressure helium gas in a guided geometry. We apply this approach to a TW chirped-pulse-amplification based Ti:Sapphire laser chain and show that spectral broadening can be controlled both with the input pulse energy and gas pressure. Under optimized conditions, we generate 10 fs pulses at TW level directly under vacuum and demonstrate a high stability of the post compressed pulse duration. These high energy post-compressed pulses are thereafter used to perform high harmonic generation in a loose focusing geometry. The XUV beam is characterized both spatially and spectrally on a single shot basis and structured continuous XUV spectra are observed.

  16. A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier-Stokes Equations

    E-Print Network [OSTI]

    Peraire, Jaime

    A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier;A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier adaptation for high-order discretizations and simplex, cut-cell mesh generation. First, output-based mesh

  17. Modular low-aspect-ratio high-beta torsatron

    DOE Patents [OSTI]

    Sheffield, G.V.

    1982-04-01T23:59:59.000Z

    A fusion-reactor device is described which the toroidal magnetic field and at least a portion of the poloidal magnetic field are provided by a single set of modular coils. The coils are arranged on the surface of a low-aspect-ratio toroid in planed having the cylindrical coordinate relationship phi = phi/sub i/ + kz, where k is a constant equal to each coil's pitch and phi/sub i/ is the toroidal angle at which the i'th coil intersects the z = o plane. The toroid defined by the modular coils preferably has a race track minor cross section. When vertical field coils and, preferably, a toroidal plasma current are provided for magnetic-field-surface closure within the toroid, a vacuum magnetic field of racetrack-shaped minor cross section with improved stability and beta valves is obtained.

  18. COMPRESSIVE INVERSE SCATTERING I. HIGH FREQUENCY SIMO/MISO AND MIMO MEASUREMENTS

    E-Print Network [OSTI]

    Fannjiang, Albert

    COMPRESSIVE INVERSE SCATTERING I. HIGH FREQUENCY SIMO/MISO AND MIMO MEASUREMENTS ALBERT C), multiple-input-single-output (MISO) or multiple-input-multiple-output (MIMO) measurements is analyzed of the data either with the MIMO measurement for the Born scattering or with the SIMO/MISO measurement

  19. High performance digital video servers: storage and retrieval of compressed scalable video

    E-Print Network [OSTI]

    Chang, Shih-Fu

    High performance digital video servers: storage and retrieval of compressed scalable video Seungyup compressiontechnologyhave ledto the emergence ofunprecedented forms of video communications. In the future, it is envisioned that users will be able to connect to a massive number of distributed video servers, from which users

  20. Fabrication of high gradient insulators by stack compression

    DOE Patents [OSTI]

    Harris, John Richardson; Sanders, Dave; Hawkins, Steven Anthony; Norona, Marcelo

    2014-04-29T23:59:59.000Z

    Individual layers of a high gradient insulator (HGI) are first pre-cut to their final dimensions. The pre-cut layers are then stacked to form an assembly that is subsequently pressed into an HGI unit with the desired dimension. The individual layers are stacked, and alignment is maintained, using a sacrificial alignment tube that is removed after the stack is hot pressed. The HGI's are used as high voltage vacuum insulators in energy storage and transmission structures or devices, e.g. in particle accelerators and pulsed power systems.

  1. High Fidelity Modeling of Premixed Charge Compression Ignition Engines |

    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), GeothermalGridHYDROGEN TOTechnologyHigh Efficiency Low -1Department

  2. Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly

    E-Print Network [OSTI]

    Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly Circular Plasma­boundary, high­beta equi­ libria in large aspect ratio tokamaks with a nearly circular plasma boundary in tokamaks for the purpose of developing an economic fusion reactor. It has long been recognized

  3. HIGH-GRADIENT, HIGH-TRANSFORMER-RATIO, DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-04-12T23:59:59.000Z

    The Phase I work reported here responds to DoE'ss stated need "...to develop improved accelerator designs that can provide very high gradient (>200 MV/m for electrons...) acceleration of intense bunches of particles." Omega-P'�s approach to this goal is through use of a ramped train of annular electron bunches to drive a coaxial dielectric wakefield accelerator (CDWA) structure. This approach is a direct extension of the CDWA concept from acceleration in wake fields caused by a single drive bunch, to the more efficient acceleration that we predict can be realized from a tailored (or ramped) train of several drive bunches. This is possible because of a much higher transformer ratio for the latter. The CDWA structure itself has a number of unique features, including: a high accelerating gradient G, potentially with G > 1 GeV/m; continuous energy coupling from drive to test bunches without transfer structures; inherent transverse focusing forces for particles in the accelerated bunch; highly stable motion of high charge annular drive bunches; acceptable alignment tolerances for a multi-section system. What is new in the present approach is that the coaxial dielectric structure is now to be energized by-not one-�but by a short train of ramped annular-shaped drive bunches moving in the outer coaxial channel of the structure. We have shown that this allows acceleration of an electron bunch traveling along the axis in the inner channel with a markedly higher transformer ratio T than for a single drive bunch. As described in this report, the structure will be a GHz-scale prototype with cm-scale transverse dimensions that is expected to confirm principles that can be applied to the design of a future THz-scale high gradient (> 500 MV/m) accelerator with mm-scale transverse dimensions. We show here a new means to significantly increase the transformer ratio T of the device, and thereby to significantly improve its suitability as a flexible and effective component in a future high energy, high gradient accelerator facility. We predict that the T of a high gradient CDWA can be increased by a substantial factor; this enhancement is dramatically greater than what has been demonstrated heretofore. This large enhancement in T that we predict arises from using a train of three or four drive bunches in which the spacing of the bunches and their respective charges are selected according to a simple principle that requires each bunch lose energy to the wakefields at the same rate, so as not to sacrifice drive beam efficiency�¢����as would be the case if one bunch exhausted its available energy while others had not. It is anticipated that results from the study proposed here can have a direct impact on design of the dielectric accelerator in a TeV-scale collider concept, and in the accelerator for an x-ray FEL.

  4. Stability of highly shifted equilibria in a large-aspect-ratio tokamak

    E-Print Network [OSTI]

    Gourdain, P A

    2006-01-01T23:59:59.000Z

    in a large aspect ratio tokamak P. -A. Gourdain, S. C.High beta poloidal tokamaks can confine plasma pressures ansymmetric configuration called tokamak, where a plasma (i.e.

  5. Ultra-low-loss high-aspect-ratio Si3N4 wavequides

    E-Print Network [OSTI]

    2011-01-01T23:59:59.000Z

    R. Gao, and A. Garito, “Ultra-Low-Loss Polymer Waveguides,”Ultra-low-loss high-aspect-ratio Si 3 N 4 waveguides Jaredan approach to make ultra-low-loss waveguides using stable

  6. MULTISCALE RANDOM PROJECTIONS FOR COMPRESSIVE CLASSIFICATION Marco F. Duarte,r

    E-Print Network [OSTI]

    of sam- pling and compression [1, 2]. CS enables the design of new kinds of compressive imaging systems ratio test; in the case of image classification, it exploits the fact that a set of images of a fixed- quires compressive image projections, we achieve high clas- sification rates using many fewer

  7. Isothermal and shock compression of high density ammonium nitrate and ammonium perchlorate

    SciTech Connect (OSTI)

    Sandstrom, F.W.; Persson, P.A. (Research Center for Engergetic Materials, New Mexico Institute of Mining and Technology Socorro, New Mexico 87801 (United States)); Olinger, B. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

    1994-07-10T23:59:59.000Z

    Bulk sound speed measurements, isothermal volume compression/X-ray diffraction experiments and shock loading experiments (maximum pressure [approx]20 GPa) have been performed for high initial density ([ge]94% TMD) ammonium nitrate (AN) and ammonium perchlorate (AP). The experimental data, and full density Hugoniots calculated from that data, suggest the presence of low pressure, shock induced phase transitions in both the AN and AP. The AP phase transition occurs at [approx]4 GPa, and exhibits characteristics of a high density to low density phase transition, but the present data are not conclusive. The AN phase change occurs at a shock pressure of less than 3.5 GPa, but the associated volume change is relatively large, indicating the presence of a previously unidentified high pressure, high density phase. [copyright]American Institute of Physics

  8. High M/L ratios of UCDs: a variation of the IMF?

    E-Print Network [OSTI]

    S. Mieske; J. Dabringhausen; P. Kroupa; M. Hilker; H. Baumgardt

    2008-09-29T23:59:59.000Z

    Various studies have established that the dynamical M/L ratios of ultra-compact dwarf galaxies (UCDs) tend to be at the limit or beyond the range explicable by standard stellar populations with canonical IMF. We discuss how IMF variations may account for these high M/L ratios and how observational approaches may in the future allow to discriminate between those possibilities. We also briefly discuss the possibility of dark matter in UCDs.

  9. A Compressible High-Order Unstructured Spectral Difference Code for Stratified Convection in Rotating Spherical Shells

    E-Print Network [OSTI]

    Wang, Junfeng; Miesch, Mark S

    2015-01-01T23:59:59.000Z

    We present a novel and powerful Compressible High-ORder Unstructured Spectral-difference (CHORUS) code for simulating thermal convection and related fluid dynamics in the interiors of stars and planets. The computational geometries are treated as rotating spherical shells filled with stratified gas. The hydrodynamic equations are discretized by a robust and efficient high-order Spectral Difference Method (SDM) on unstructured meshes. The computational stencil of the spectral difference method is compact and advantageous for parallel processing. CHORUS demonstrates excellent parallel performance for all test cases reported in this paper, scaling up to 12,000 cores on the Yellowstone High-Performance Computing cluster at NCAR. The code is verified by defining two benchmark cases for global convection in Jupiter and the Sun. CHORUS results are compared with results from the ASH code and good agreement is found. The CHORUS code creates new opportunities for simulating such varied phenomena as multi-scale solar co...

  10. Extension of the high load limit in the Homogeneous Charge Compression Ignition engine

    E-Print Network [OSTI]

    Scaringe, Robert J. (Robert Joseph)

    2009-01-01T23:59:59.000Z

    The Homogeneous Charge Compression Ignition (HCCI) engine offers diesel-like efficiency with very low soot and NOx emissions. In a HCCI engine, a premixed charge of air, fuel and burned gas is compressed to achieve ...

  11. Nano-scaled graphene platelets with a high length-to-width aspect ratio

    DOE Patents [OSTI]

    Zhamu, Aruna (Centerville, OH); Guo, Jiusheng (Centerville, OH); Jang, Bor Z. (Centerville, OH)

    2010-09-07T23:59:59.000Z

    This invention provides a nano-scaled graphene platelet (NGP) having a thickness no greater than 100 nm and a length-to-width ratio no less than 3 (preferably greater than 10). The NGP with a high length-to-width ratio can be prepared by using a method comprising (a) intercalating a carbon fiber or graphite fiber with an intercalate to form an intercalated fiber; (b) exfoliating the intercalated fiber to obtain an exfoliated fiber comprising graphene sheets or flakes; and (c) separating the graphene sheets or flakes to obtain nano-scaled graphene platelets. The invention also provides a nanocomposite material comprising an NGP with a high length-to-width ratio. Such a nanocomposite can become electrically conductive with a small weight fraction of NGPs. Conductive composites are particularly useful for shielding of sensitive electronic equipment against electromagnetic interference (EMI) or radio frequency interference (RFI), and for electrostatic charge dissipation.

  12. Synthesis and Electric Field-Manipulation of High Aspect Ratio Barium Titanate

    E-Print Network [OSTI]

    Li, Junjia

    2012-07-16T23:59:59.000Z

    requirements for a minimum effective dielectric constant. Thus, to achieve the goals above, we synthesized high aspect ratio BaTiO3 nanowires with BaC2O4 and TiO2 powders as precursors using a molten salt method. The as-synthesized BaTiO3 nanowires were...

  13. 1 Copyright 2004 by ASME SINGLE HIGH ASPECT RATIO PILLAR SUPPORT STRUCTURES

    E-Print Network [OSTI]

    , or build them up layer by layer[1]. These fabrication techniques have led to the creation of new device1 Copyright © 2004 by ASME SINGLE HIGH ASPECT RATIO PILLAR SUPPORT STRUCTURES: Multi-scale Chip for conformance to the surface prior to larger scale conformation, thus the combination does not increase

  14. UV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING

    E-Print Network [OSTI]

    in microfabrication. Table 1 compares the performance of UV-LEDs with a mercury lamp for several key parametersUV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING Jungkwun `JK' Kim*, Seung of Technology, Atlanta, GA, USA ABSTRACT This paper presents a UV lithography method that utilizes a UV-LED

  15. Prediction of Ultra-High Aspect Ratio Nanowires from Self-Assembly

    E-Print Network [OSTI]

    Wu, Zhigang

    a combination of ab initio total energy calculations and classical molecular dynamics (MD) simulations ratio nanowires with high-quality alignment. We show that the electronic structure of the resulting. The ab initio calculations provide key information regarding selective chemical functionalization for end

  16. SINGLE-MASK, HIGH ASPECT RATIO, 3-D MICROMACHINING OF BULK TITANIUM , M. F. Aimi2

    E-Print Network [OSTI]

    MacDonald, Noel C.

    SINGLE-MASK, HIGH ASPECT RATIO, 3-D MICROMACHINING OF BULK TITANIUM M. P. Rao1 , M. F. Aimi2 , E. R profiles in bulk titanium. The method relies on the exploitation of Reactive Ion Etching Lag (RIE Lag for application in bulk micromachined titanium micromirror devices. 1. INTRODUCTION The recent development

  17. Peristaltic pumping of a viscoelastic fluid at high occlusion ratios and large Weissenberg numbers

    E-Print Network [OSTI]

    Bigelow, Stephen

    Peristaltic pumping of a viscoelastic fluid at high occlusion ratios and large Weissenberg numbers pumping is a mechanism for transporting fluid or immersed par- ticles in a channel by waves of contraction- vestigate numerically the peristaltic pumping of an incompressible viscoelas- tic fluid using the simple

  18. Compressing bitmap indexes for faster search operations

    E-Print Network [OSTI]

    Wu, Kesheng; Otoo, Ekow J.; Shoshani, Arie

    2002-01-01T23:59:59.000Z

    study the effects of compression on bitmap indexes. The mainvalues. With- out compression, the bitmap index size wouldBBC WAH compression ratio (b) STAR bitmap indexes Figure 6.

  19. A New Approach for Fingerprint Image Compression

    SciTech Connect (OSTI)

    Mazieres, Bertrand

    1997-12-01T23:59:59.000Z

    The FBI has been collecting fingerprint cards since 1924 and now has over 200 million of them. Digitized with 8 bits of grayscale resolution at 500 dots per inch, it means 2000 terabytes of information. Also, without any compression, transmitting a 10 Mb card over a 9600 baud connection will need 3 hours. Hence we need a compression and a compression as close to lossless as possible: all fingerprint details must be kept. A lossless compression usually do not give a better compression ratio than 2:1, which is not sufficient. Compressing these images with the JPEG standard leads to artefacts which appear even at low compression rates. Therefore the FBI has chosen in 1993 a scheme of compression based on a wavelet transform, followed by a scalar quantization and an entropy coding : the so-called WSQ. This scheme allows to achieve compression ratios of 20:1 without any perceptible loss of quality. The publication of the FBI specifies a decoder, which means that many parameters can be changed in the encoding process: the type of analysis/reconstruction filters, the way the bit allocation is made, the number of Huffman tables used for the entropy coding. The first encoder used 9/7 filters for the wavelet transform and did the bit allocation using a high-rate bit assumption. Since the transform is made into 64 subbands, quite a lot of bands receive only a few bits even at an archival quality compression rate of 0.75 bit/pixel. Thus, after a brief overview of the standard, we will discuss a new approach for the bit-allocation that seems to make more sense where theory is concerned. Then we will talk about some implementation aspects, particularly for the new entropy coder and the features that allow other applications than fingerprint image compression. Finally, we will compare the performances of the new encoder to those of the first encoder.

  20. A high ON/OFF ratio organic film for photo- and electro-dual-mode recording

    SciTech Connect (OSTI)

    Li Heng [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China); Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solid, Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Wen Yongqiang; Li Gang; Ma Ying; Yang Lianming; Song Yanlin; Zhu Daoben [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solid, Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Li Pengwei; Wang Rongming [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China); Yang Qinglin [School of Chemistry and Environment, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China)

    2009-04-20T23:59:59.000Z

    To improve the stability of organic multifunctional materials and enhance the ON/OFF ratio, a donor-{pi}-acceptor molecule with the triphenylamine (TPA) unit is designed and synthesized. The TPA unit can effectively stabilize the charge transferred state, and the thin film shows excellent bistable electronic switching behavior with high ON/OFF current ratio of about 10{sup 5}. Meanwhile, reversible and stable nanometer-scale data storage is realized on the thin film by applying pulsed voltages, and optical information storage is achieved simultaneously by utilizing fluorescence changes under UV irradiation.

  1. High Efficiency Low Cost CO2 Compression Using Supersonic Shock Wave Technology

    SciTech Connect (OSTI)

    Williams, J; Aarnio, M; Grosvenor, A; Taylor, D; Bucher, J

    2010-12-31T23:59:59.000Z

    Development and testing results from a supersonic compressor are presented. The compressor achieved record pressure ratio for a fully-supersonic stage and successfully demonstrated the technology potential. Several tasks were performed in compliance with the DOE award objectives. A high-pressure ratio compressor was retrofitted to improve rotordynamics behavior and successfully tested. An outside review panel confirmed test results and design approach. A computational fluid dynamics code used to analyze the Ramgen supersonic flowpath was extensively and successfully modified to improve use on high-performance computing platforms. A comprehensive R&D implementation plan was developed and used to lay the groundwork for a future full-scale compressor demonstration. Conceptual design for a CO2 demonstration compressor was developed and reviewed.

  2. Light emitting diode with high aspect ratio submicron roughness for light extraction and methods of forming

    DOE Patents [OSTI]

    Li, Ting (Ventura, CA)

    2011-04-26T23:59:59.000Z

    The surface morphology of an LED light emitting surface is changed by applying a reactive ion etch (RIE) process to the light emitting surface. High aspect ratio, submicron roughness is formed on the light emitting surface by transferring a thin film metal hard-mask having submicron patterns to the surface prior to applying a reactive ion etch process. The submicron patterns in the metal hard-mask can be formed using a low cost, commercially available nano-patterned template which is transferred to the surface with the mask. After subsequently binding the mask to the surface, the template is removed and the RIE process is applied for time duration sufficient to change the morphology of the surface. The modified surface contains non-symmetric, submicron structures having high aspect ratio which increase the efficiency of the device.

  3. Light emitting diode with high aspect ratio submicron roughness for light extraction and methods of forming

    DOE Patents [OSTI]

    Li, Ting

    2013-08-13T23:59:59.000Z

    The surface morphology of an LED light emitting surface is changed by applying a reactive ion etch (RIE) process to the light emitting surface. High aspect ratio, submicron roughness is formed on the light emitting surface by transferring a thin film metal hard-mask having submicron patterns to the surface prior to applying a reactive ion etch process. The submicron patterns in the metal hard-mask can be formed using a low cost, commercially available nano-patterned template which is transferred to the surface with the mask. After subsequently binding the mask to the surface, the template is removed and the RIE process is applied for time duration sufficient to change the morphology of the surface. The modified surface contains non-symmetric, submicron structures having high aspect ratio which increase the efficiency of the device.

  4. An implicit wetting and drying approach for non-hydrostatic flows in high aspect ratio domains

    E-Print Network [OSTI]

    Candy, Adam S

    2013-01-01T23:59:59.000Z

    A wetting and drying approach for free surface flows governed by the three-dimensional, non-hydrostatic Navier-Stokes equations in high aspect ratio domains is developed. This has application in the modelling of inundation processes in geophysical domains, where dynamics takes place over a large horizontal extent relative to vertical resolution, such as in the evolution of a tsunami, or an urban fluvial flooding scenario. The approach is novel in that it solves for three dimensional dynamics in these very high aspect ratio domains, to include non-hydrostatic effects and accurately model dispersive processes. These become important in shallow regions with steep gradients, a particularly acute problem where man-made structures exist such as buildings or flood defences in an urban environment. It is implicit in time to allow efficient time integration over a range of mesh element sizes. Specific regularisation methods are introduced to improve conditioning of the full three-dimensional pressure Poisson problem i...

  5. Growth of Early Supermassive Black Holes and the High-Redshift Eddington Ratio Distribution

    E-Print Network [OSTI]

    DeGraf, Colin; Khandai, Nishikanta; Croft, Rupert

    2012-01-01T23:59:59.000Z

    Using a new large-scale (~ 0.75 Gpc)^3 hydrodynamic cosmological simulation we investigate the growth rate of supermassive black holes in the early universe (z > 4.75). Remarkably, we find a clear peak in the typical Eddington ratio at black hole masses of 4-8 * 10^7 solar masses (typically found in halos of ~7 * 10^11 to 10^12 solar masses), independent of redshift and indicative that most of BH growth occurs in the cold-flow dominated regime. Black hole growth is by and large regulated by the evolution of gas density. The typical Eddington ratio at a given mass scales simply as cosmological density (1+z)^3 and the peak is caused by the competition between increased gas density available in more massive hosts, and a decrease due to strong AGN feedback that deprives the black hole of sufficient gas to fuel further rapid growth in the high mass end. In addition to evolution in the mean Eddington ratio, we show that the distribution of Eddington ratio among both mass-selected and luminosity-selected samples is ...

  6. Stages of destruction and elastic compression of granular nanoporous carbon medium at high pressures

    E-Print Network [OSTI]

    I. M. Neklyudov; O. P. Ledenyov; N. B. Bobrova; A. A. Chupikov

    2015-05-14T23:59:59.000Z

    The granular nanoporous carbon medium, made of the cylindrical coal granules of the adsorbent of SKT 3, at an influence by the high pressures from 1MPa to 3GPa has been researched. The eight consecutive stages of the materials specific volume change, which is characterized by a certain dependence of the volume change on the pressure change, have been registered. It is shown that there is a linear dependence on the double log log plot of the materials specific volume change on the pressure for an every stage of considered process. The two stages are clearly distinguished such as a stage of materials mechanical destruction, and a stage of elastic compression of material without the disintegration of structure at a nanscale. The hysteresis dependence of the materials specific volume change on the pressure change at the pressure decrease is observed. The small disperse coal dust particles jettisoning between the high pressure cell and the base plate was observed, resulting in the elastic stress reduction in relation to the small disperse coal dust particles volume. The obtained research data can be used to improve the designs of air filters for the radioactive chemical elements absorption at the NPP with the aims to protect the environment.

  7. mm-WAVE Op-Amps FOR LOW DISTORTION AMPLIFICATION WITH HIGH OIP3/PDC RATIO > 100 AT 2 GHz

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    mm-WAVE Op-Amps FOR LOW DISTORTION AMPLIFICATION WITH HIGH OIP3/PDC RATIO > 100 AT 2 GHz Zach in bandwidth for an op-amp of any kind, as well as 3Ã? betterment in OIP3/PDC ratio at fs = 2-3 GHz, when dissipation PDC. This very high ratio of third-order-intercept power to DC power consumption POIP 3/PDC > 100

  8. New experimental platform to study high density laser-compressed matter

    SciTech Connect (OSTI)

    Gauthier, M., E-mail: maxence.gauthier@stanford.edu; Fletcher, L. B.; Galtier, E.; Gamboa, E. J.; Granados, E.; Hastings, J. B.; Heimann, P.; Lee, H. J.; Nagler, B.; Schropp, A.; Falcone, R.; Glenzer, S. H. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Ravasio, A. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); LULI, Ecole Polytechnique, Palaiseau (France); Gleason, A. [Department of Geological and Environmental Sciences, Stanford University, Menlo Park, California 94025 (United States); Döppner, T.; LePape, S.; Ma, T.; Pak, A. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); MacDonald, M. J. [Atmospheric, Oceanic, and Space Science Department, University of Michigan, Ann Arbor, Michigan 48109 (United States); Ali, S. [Physics Department, University of California Berkeley, Berkeley, California 94709 (United States); and others

    2014-11-15T23:59:59.000Z

    We have developed a new experimental platform at the Linac Coherent Light Source (LCLS) which combines simultaneous angularly and spectrally resolved x-ray scattering measurements. This technique offers a new insights on the structural and thermodynamic properties of warm dense matter. The < 50 fs temporal duration of the x-ray pulse provides near instantaneous snapshots of the dynamics of the compression. We present a proof of principle experiment for this platform to characterize a shock-compressed plastic foil. We observe the disappearance of the plastic semi-crystal structure and the formation of a compressed liquid ion-ion correlation peak. The plasma parameters of shock-compressed plastic can be measured as well, but requires an averaging over a few tens of shots.

  9. Secondary compression of peat with or without surcharging

    SciTech Connect (OSTI)

    Mesri, G.; Stark, T.D.; Ajlouni, M.A. [Univ. of Illinois, Urbana, IL (United States). Dept. of Civil Engineering; Chen, C.S. [Sino Geotechnology, Taipei (Taiwan, Province of China)

    1997-05-01T23:59:59.000Z

    Secondary compression is important in peat deposits because they exist at high void ratios and exhibit high values of compression index C{sub c}, display the highest values of C{sub {alpha}}/C{sub c} among geotechnical materials, and primary consolidation is completed in weeks or months in typical field situations. Secondary compression of Middleton peat was investigated by odometer tests on undisturbed specimens. The observed secondary compression behavior of this fibrous peat, with or without surcharging, is in accordance with the C{sub {alpha}}/C{sub c} concept of compressibility. Near the preconsolidation pressure, the secondary compression index, C{sub {alpha}}, increases significantly with time. In the compression range C{sub {alpha}} decreases only slightly with time, and for most practical purposes a constant C{sub {alpha}} with time can be used to compute secondary settlement. Postsurcharge secondary compression index, C{prime}{sub {alpha}}, always increases with time. This is predicted by the C{sub {alpha}}/C{sub c} concept of compressibility. A secant post-surcharge secondary compression index, C{double_prime}{sub {alpha}}, is therefore introduced for a simple computation of secondary settlement.

  10. An interface facet driven Rayleigh instability in high-aspect-ratio bimetallic nanolayered composites

    SciTech Connect (OSTI)

    Zheng, Shijian, E-mail: sjzheng@lanl.gov, E-mail: sjzhengsj@gmail.com; Mara, Nathan A. [Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Carpenter, John S. [Materials Science and Technology Division, MST-6, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Wang, Jian [Materials Science and Technology Division, MST-8, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Beyerlein, Irene J. [Theoretical Division, T-3, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-09-15T23:59:59.000Z

    One limitation hindering the structural and electrical applications of nanostructured metals is the loss of their nanostructure and strength under elevated temperatures. Nanostructured metals often have grain structures that contain a high density of triple junctions, where thermally induced instabilities commonly initiate. Prior work has resulted in fabrication of nanolayered two-phase composites that possess high-aspect ratio grains, a scarcity of triple junctions, and a thermally stable microstructure. In this work, transmission electron microscopy is used to investigate how these composites could eventually breakdown during heating. We reveal an unconventional thermal instability mechanism in this class of materials, which operates without the assistance of triple junctions. The mechanism can be rationalized by that thermally induced pinch off occurs as the result of bimetal interface faceting and can trigger a classic Rayleigh instability.

  11. Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to High Momentum Transfer

    SciTech Connect (OSTI)

    Andrew Puckett

    2010-02-01T23:59:59.000Z

    The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions of the squared four-momentum transfer Q2 between the electron and the proton. The two main classes of observables of this reaction are the scattering cross section and polarization asymmetries, both of which are sensitive to the form factors in different ways. When considering large f momentum transfers, double-polarization observables offer superior sensitivity to the electric form factor. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton at high momentum transfer using the recoil polarization technique. A polarized electron beam was scattered from a liquid hydrogen target, transferring polarization to the recoiling protons. These protons were detected in a magnetic spectrometer which was used to reconstruct their kinematics, including their scattering angles and momenta, and the position of the interaction vertex. A proton polarimeter measured the polarization of the recoiling protons by measuring the azimuthal asymmetry in the angular distribution of protons scattered in CH2 analyzers. The scattered electron was detected in a large acceptance electromagnetic calorimeter in order to suppress inelastic backgrounds. The measured ratio of the transverse and longitudinal polarization components of the scattered proton is directly proportional to the ratio of form factors GpE=GpM. The measurements reported in this thesis took place at Q2 =5.2, 6.7, and 8.5 GeV2, and represent the most accurate measurements of GpE in this Q2 region to date.

  12. The profile likelihood ratio and the look elsewhere effect in high energy physics

    E-Print Network [OSTI]

    Gioacchino Ranucci

    2012-01-22T23:59:59.000Z

    The experimental issue of the search for new particles of unknown mass poses the challenge of exploring a wide interval to look for the usual signatures represented by excess of events above the background. A side effect of such a broad range quest is that the significance calculations valid for signals of known location are no more applicable when such an information is missing. This circumstance is commonly termed in high energy physics applications as the look elsewhere effect. How it concretely manifests in a specific problem of signal search depends upon the particular strategy adopted to unravel the sought-after signal from the underlying background. In this respect an increasingly popular method is the profile likelihood ratio, especially because of its asymptotic behavior dictated by one of the most famous statistic result, the Wilks' theorem. This work is centered on the description of the look elsewhere effect in the framework of the profile likelihood methodology, in particular proposing a conjecture about the distribution of the likelihood ratio under the null hypothesis of absence of the signal over the searched mass interval, a condition which is known to violate the conditions of the Wilks' theorem. Several Monte Carlo tests to support the conjecture are presented, as well.

  13. Carbon Isotope Ratio in 12 CO/ 13 CO toward Local Molecular Clouds with Near-Infrared High Resolution Spectroscopy of

    E-Print Network [OSTI]

    Usuda, Tomonori

    ), therefore serves as a chronological measure of the chemical enrichment of the galaxy. The isotopic ratio of the Galactic plane. The 13 C isotope is produced faster there, rapidly enriching the interstellar medium (ISMCarbon Isotope Ratio in 12 CO/ 13 CO toward Local Molecular Clouds with Near-Infrared High

  14. Measurement and simulation of jet mass caused by a high-aspect ratio hole perturbation

    SciTech Connect (OSTI)

    Keiter, Paul A [Los Alamos National Laboratory; Cooley, James H [Los Alamos National Laboratory; Wilson, D C [Los Alamos National Laboratory; Kyrala, George A [Los Alamos National Laboratory; Blue, Brent E [LLNL; Edwards, J [LLNL; Elliott, James B [LLNL; Robey, H F [LLNL; Spears, B [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    Inertial confinement fusion (ICF) capsule performance can be negatively impacted by the presence of hydrodynamic instabilities. To perform a gas fill on an ICF capsule, current plans involve drilling a small hole and inserting a fill tube to inject the gas mixture into the capsule. This introduces a perturbation on the capsule, which can seed hydrodynamic instabilities. The small hole can cause jetting of the shell material into the gas, which might adversely affect the capsule performance. We have performed simulations and experiments to study the hydrodynamic evolution of jets from high-aspect ratio holes, such as the fill tube hole. Although simulations using cold materials overpredict the amount of mass in the jet, when a reasonable amount of preheat (<1 eV) is introduced, the simulations are in better agreement with the experiment.

  15. Effective electro-optical modulation with high extinction ratio by a graphene-silicon microring resonator

    E-Print Network [OSTI]

    Ding, Yunhong; Xiao, Sanshui; Hu, Hao; Frandsen, Lars Hagedorn; Mortensen, N Asger; Yvind, Kresten

    2015-01-01T23:59:59.000Z

    Graphene opens up for novel optoelectronic applications thanks to its high carrier mobility, ultra-large absorption bandwidth, and extremely fast material response. In particular, the opportunity to control optoelectronic properties through tuning of Fermi level enables electro-optical modulation, optical-optical switching, and other optoelectronics applications. However, achieving a high modulation depth remains a challenge because of the modest graphene-light interaction in the graphene-silicon devices, typically, utilizing only a monolayer or few layers of graphene. Here, we comprehensively study the interaction between graphene and a microring resonator, and its influence on the optical modulation depth. We demonstrate graphene-silicon microring devices showing a high modulation depth of 12.5 dB with a relatively low bias voltage of 8.8 V. On-off electro-optical switching with an extinction ratio of 3.8 dB is successfully demonstrated by applying a square-waveform with a 4 V peak-to-peak voltage.

  16. Adaptive AFM scan speed control for high aspect ratio fast structure tracking

    SciTech Connect (OSTI)

    Ahmad, Ahmad; Schuh, Andreas; Rangelow, Ivo W. [Department of Microelectronic and Nanoelectronic Systems, Faculty of Electrical Engineering and Information Technology Ilmenau University of Technology, Gustav-Kirchhoffstr. 1, 98684 Ilmenau (Germany)

    2014-10-15T23:59:59.000Z

    Improved imaging rates in Atomic Force Microscopes (AFM) are of high interest for disciplines such as life sciences and failure analysis of semiconductor wafers, where the sample topology shows high aspect ratios. Also, fast imaging is necessary to cover a large surface under investigation in reasonable times. Since AFMs are composed of mechanical components, they are associated with comparably low resonance frequencies that undermine the effort to increase the acquisition rates. In particular, high and steep structures are difficult to follow, which causes the cantilever to temporarily loose contact to or crash into the sample. Here, we report on a novel approach that does not affect the scanner dynamics, but adapts the lateral scanning speed of the scanner. The controller monitors the control error signal and, only when necessary, decreases the scan speed to allow the z-piezo more time to react to changes in the sample's topography. In this case, the overall imaging rate can be significantly increased, because a general scan speed trade-off decision is not needed and smooth areas are scanned fast. In contrast to methods trying to increase the z-piezo bandwidth, our method is a comparably simple approach that can be easily adapted to standard systems.

  17. High-energy ultrashort laser pulse compression in hollow planar waveguides

    E-Print Network [OSTI]

    Boyer, Edmond

    can be avoided by adjustment of the gas pressure. The spectral broadening is spatially uniform over by nonlinear propagation inside gas-filled planar hollow waveguides. We adjust the input beam size along can be achieved through pulse compression schemes such as gas- filled hollow core fibers [4

  18. Plasma polymerization of C[subscript 4]F[subscript 8] thin film on high aspect ratio silicon molds

    E-Print Network [OSTI]

    Yeo, L. P.

    High aspect ratio polymeric micro-patterns are ubiquitous in many fields ranging from sensors, actuators, optics, fluidics and medical. Second generation PDMS molds are replicated against first generation silicon molds ...

  19. Global well-posedness for the compressible Navier-Stokes equations with the highly oscillating initial velocity

    E-Print Network [OSTI]

    Qionglei Chen; Changxing Miao; Zhifei Zhang

    2009-08-02T23:59:59.000Z

    Cannone \\cite{Cannone} proved the global well-posedness of the incompressible Navier-Stokes equations for a class of highly oscillating data. In this paper, we prove the global well-posedness for the compressible Navier-Stokes equations in the critical functional framework with the initial data close to a stable equilibrium. Especially, this result allows us to construct global solutions for the highly oscillating initial velocity. The proof relies on a new estimate for the hyperbolic/parabolic system with convection terms.

  20. Scaling of high-wavenumber energy spectra in the unit aspect-ratio rotating Boussinesq system

    E-Print Network [OSTI]

    Susan Kurien

    2010-07-13T23:59:59.000Z

    Phenomenological and numerical studies of the small scale spectra of energy are presented for high Reynolds number rotating Boussinesq flows in unit aspect-ratio domains. We introduce a non-dimensional parameter Gamma such that when the potential vorticity is nearly linear in the dynamical variables, we deduce that for Gamma much less than 1, the potential enstrophy suppresses the transfer of horizontal kinetic energy into wavemodes with large horizontal component k_h while forcing it to become independent of vertical wavevector component k_z, scaling as k_h^{-5}. When Gamma much greater than 1, the potential enstrophy suppresses the transfer of potential energy into the wavemodes with large vertical component k_z while forcing it to become independent of k_h, scaling as k_z^{-5) power. Spectra computed from high-resolution simulations of the Boussinesq equations with isotropic low-wavenumber forcing are used to explore such anisotropic constraints on the energy and provide a posteriori justification for the joint flux ansatz used to obtain the (-5) scaling exponent. In all cases the empirical evidence points to both energy and potential enstrophy being jointly transferred downscale with the spectral scaling of the the former constrained by the latter.

  1. Wavelet/scalar quantization compression standard for fingerprint images

    SciTech Connect (OSTI)

    Brislawn, C.M.

    1996-06-12T23:59:59.000Z

    US Federal Bureau of Investigation (FBI) has recently formulated a national standard for digitization and compression of gray-scale fingerprint images. Fingerprints are scanned at a spatial resolution of 500 dots per inch, with 8 bits of gray-scale resolution. The compression algorithm for the resulting digital images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition (wavelet/scalar quantization method). The FBI standard produces archival-quality images at compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. The compression standard specifies a class of potential encoders and a universal decoder with sufficient generality to reconstruct compressed images produced by any compliant encoder, allowing flexibility for future improvements in encoder technology. A compliance testing program is also being implemented to ensure high standards of image quality and interchangeability of data between different implementations.

  2. Water condensation behavior on the surface of a network of superhydrophobic carbon fibers with high-aspect-ratio

    E-Print Network [OSTI]

    Kim, Ho-Young

    Water condensation behavior on the surface of a network of superhydrophobic carbon fibers with high on a superhydrophobic carbon fiber (CF) network with high-aspect-ratio hair-like nanostructures. Nanostructures ranging. Superhydrophobic CF surfaces were achieved by application of a hydrophobic siloxane- based hydrocarbon coating

  3. D. Moreau IEA W59 Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamaks, San Diego, February 2005 PLASMA SHAPE, PROFILES AND FLUX CONTROL

    E-Print Network [OSTI]

    D. Moreau IEA W59 Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamaks, San JET-EFDA Contributors D. Moreau #12;D. Moreau IEA W59 Shape and Aspect Ratio Optimization for High · Conclusion #12;D. Moreau IEA W59 Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamaks

  4. High-precision optical measurements of 13 isotope ratios in organic compounds at

    E-Print Network [OSTI]

    Zare, Richard N.

    range with an average precision of 0.95 and 0.67 for ethane and propane, respec- tively. The calibrated accuracy for methane, ethane, and propane is within 3 of the values determined using isotope ratio mass place in chemistry, especially in geochemistry, for determining reaction mechanisms and pro- viding

  5. High precision measurement of the proton elastic form factor ratio at low Q²

    E-Print Network [OSTI]

    Zhan, Xiaohui

    2010-01-01T23:59:59.000Z

    Experiment E08-007 measured the proton elastic form factor ratio [mu]GE/GM in the range of Q2 = 0.3-0.7(GeV/c)2 by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator Facility in Virginia, ...

  6. Optimal Core Dimensional Ratios for Minimizing Winding Loss in High-Frequency

    E-Print Network [OSTI]

    to optimum provides a 32% savings in power loss compared to another popular core shape. Further improvements in power loss could be achieved by using optimized core shapes. Improvements to software for shape. This optimum aspect ratio is a function of frequency and other parameters. Significant increases in power loss

  7. air-fuel ratio: Topics by E-print Network

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

    was performed to investigate the effects of air-fuel ratio, inlet boost pressure, hydrogen rich fuel reformate, and compression ratio on engine knock behavior. For each...

  8. Accepted to Combustion and Flame Feb. 11, 2004 Demonstration of a Free-Piston Rapid Compression Facility for the Study of High

    E-Print Network [OSTI]

    Wooldridge, Margaret S.

    Accepted to Combustion and Flame Feb. 11, 2004 Demonstration of a Free-Piston Rapid Compression Facility for the Study of High Temperature Combustion Phenomena M. T. Donovan, X. He, B. T. Zigler, T. R developed at the University of Michigan (UM) for use in studying high-temperature combustion phenomena

  9. Two Channel Dielectric-Lined Rectangular High Transformer Ratio Accelerator Structure Experiment

    SciTech Connect (OSTI)

    Shchelkunov, S. V.; LaPointe, M. A. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Marshall, T. C. [Columbia University, New York, NY 10027 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Sotnikov, G. [NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Gai, Wei; Conde, M.; Power, J.; Mihalcea, D. [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2010-11-04T23:59:59.000Z

    Current status of a two-channel cm-scale rectangular dielectric lined wakefield accelerator structure is described. This structure is installed at the Argonne Wakefield Accelerator facility (AWA), and is presently being evaluated. The device has a transformer ratio of {approx}12.5:1. When driven by a {approx}50 nC single drive bunch it is expected to obtain {approx}6 MV/m acceleration gradient. Related issues are discussed.

  10. Compression embedding

    SciTech Connect (OSTI)

    Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)

    1998-01-01T23:59:59.000Z

    A method and apparatus for embedding auxiliary information into the digital representation of host data created by a lossy compression technique and a method and apparatus for constructing auxiliary data from the correspondence between values in a digital key-pair table with integer index values existing in a representation of host data created by a lossy compression technique. The methods apply to data compressed with algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as ordered sequences of blocks containing integer indices having redundancy and uncertainty of value by one unit, allowing indices which are adjacent in value to be manipulated to encode auxiliary data. Also included is a method to improve the efficiency of lossy compression algorithms by embedding white noise into the integer indices. Lossy compression methods use loss-less compression to reduce to the final size the intermediate representation as indices. The efficiency of the loss-less compression, known also as entropy coding compression, is increased by manipulating the indices at the intermediate stage. Manipulation of the intermediate representation improves lossy compression performance by 1 to 10%.

  11. Compression embedding

    DOE Patents [OSTI]

    Sandford, M.T. II; Handel, T.G.; Bradley, J.N.

    1998-07-07T23:59:59.000Z

    A method and apparatus for embedding auxiliary information into the digital representation of host data created by a lossy compression technique and a method and apparatus for constructing auxiliary data from the correspondence between values in a digital key-pair table with integer index values existing in a representation of host data created by a lossy compression technique are disclosed. The methods apply to data compressed with algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as ordered sequences of blocks containing integer indices having redundancy and uncertainty of value by one unit, allowing indices which are adjacent in value to be manipulated to encode auxiliary data. Also included is a method to improve the efficiency of lossy compression algorithms by embedding white noise into the integer indices. Lossy compression methods use loss-less compression to reduce to the final size the intermediate representation as indices. The efficiency of the loss-less compression, known also as entropy coding compression, is increased by manipulating the indices at the intermediate stage. Manipulation of the intermediate representation improves lossy compression performance by 1 to 10%. 21 figs.

  12. Modeling and Analysis of Natural Gas and Gasoline In A High Compression

    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(FactDepartment3311,OfficialProducts | Department of|of EnergyEnergyRatio

  13. Compression embedding

    DOE Patents [OSTI]

    Sandford, M.T. II; Handel, T.G.; Bradley, J.N.

    1998-03-10T23:59:59.000Z

    A method of embedding auxiliary information into the digital representation of host data created by a lossy compression technique is disclosed. The method applies to data compressed with lossy algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as integer indices having redundancy and uncertainty in value by one unit. Indices which are adjacent in value are manipulated to encode auxiliary data. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user. Lossy compression methods use loss-less compressions known also as entropy coding, to reduce to the final size the intermediate representation as indices. The efficiency of the compression entropy coding, known also as entropy coding is increased by manipulating the indices at the intermediate stage in the manner taught by the method. 11 figs.

  14. Compression embedding

    DOE Patents [OSTI]

    Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)

    1998-01-01T23:59:59.000Z

    A method of embedding auxiliary information into the digital representation of host data created by a lossy compression technique. The method applies to data compressed with lossy algorithms based on series expansion, quantization to a finite number of symbols, and entropy coding. Lossy compression methods represent the original data as integer indices having redundancy and uncertainty in value by one unit. Indices which are adjacent in value are manipulated to encode auxiliary data. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user. Lossy compression methods use loss-less compressions known also as entropy coding, to reduce to the final size the intermediate representation as indices. The efficiency of the compression entropy coding, known also as entropy coding is increased by manipulating the indices at the intermediate stage in the manner taught by the method.

  15. Variable Compression Ratio Engine | 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 DensityEnergy U.S.-China Electric Vehicle and03/02 TUEValidation of Innovativeof Energy Charge

  16. High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2

    SciTech Connect (OSTI)

    Xiaohui Zhan

    2010-01-31T23:59:59.000Z

    Experiment E08-007 measured the proton elastic form factor ratio ?pGE/GM in the range of Q2 = 0.3?0.7(GeV/c)2 by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator Facility in Virginia, USA. A 1.2 GeV polarized electron beam was scattered off a cryogenic hydrogen target. The recoil proton was detected in the left HRS in coincidence with the elasticly scattered electrons tagged by the BigBite spectrometer. The proton polarization was measured by the focal plane polarimeter (FPP). In this low Q2 region, previous measurement from Jefferson Lab Hall A (LEDEX) along with various fits and calculations indicate substantial deviations of the ratio from unity. For this new measurement, the proposed statistical uncertainty (< 1%) was achieved. These new results are a few percent lower than expected from previous world data and fits, which indicate a smaller GEp at this region. Beyond the intrinsic interest in nucleon structure, the new results also have implications in determining the proton Zemach radius and the strangeness form factors from parity violation experiments.

  17. Cornering dimension-6 $HVV$ interactions at high luminosity LHC: the role of event ratios

    E-Print Network [OSTI]

    Banerjee, Shankha; Mellado, Bruce; Mukhopadhyaya, Biswarup

    2015-01-01T23:59:59.000Z

    We suggest a way of improving the probes on dimension-6 CP-conserving $HVV$ interactions ($V$ = $W$, $Z$, $\\gamma$), from the LHC data on the Higgs boson to be available in the 14 TeV run with an integrated luminosity of $3000$ fb$^{-1}$. We find that the ratios of total rates in different channels can be quite useful in this respect. This includes ratios of event rates in (a) different final states for the Higgs produced by the same production mechanism, and (b) the same final state from two different production modes. While most theoretical uncertainties cancel in the former, the latter helps in the case of those operators which shift the numerator and denominator in opposite directions. Our analysis, incorporating theoretical, systematic and statistical uncertainties, leads to projected limits that are better than the strongest ones obtained so far from precision electroweak as well as LHC Higgs data. Moreover, values of the coefficients of the dimension-6 operators, which are allowed in disjoint intervals...

  18. Materials Science and Engineering A, 2011, 528(1-2): p. 7596 7605 High strain rate compressive response ofsyntactic foams: trends in mechanical properties and failure mechanisms

    E-Print Network [OSTI]

    Gupta, Nikhil

    comprising hollow particles dispersed in a matrix material. Available studies on high strain rate compressive with respect to the material composition. Syntactic foams reinforced with micro- and nano-sized fibers are a class of porous materials in which thin-walled hollow particles are dispersed in a matrix material

  19. Neutralized Drift Compression Experiments (NDCX) with a High Intensity Ion Beam

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    a High Intensity Ion Beam P. K. Roy 1* , S. S. Yu 1 , W. L.12 , 043102 (2005). [6] P. K. Roy et al. , Nucl. Instrum.2005), p.4006. [16] P. K. Roy, S. S. Yu, E. Henestroza, A.

  20. Large-area fabrication of high aspect ratio tantalum photonic crystals for high-temperature selective emitters

    E-Print Network [OSTI]

    Rinnerbauer, Veronika

    The authors present highly selective emitters based on two-dimensional tantalum (Ta) photonic crystals, fabricated on 2 in. polycrystalline Ta substrates, for high-temperature applications, e.g., thermophotovoltaic energy ...

  1. High aspect ratio iridescent three-dimensional metal–insulator–metal capacitors using atomic layer deposition

    SciTech Connect (OSTI)

    Burke, Micheal, E-mail: micheal.burke@tyndall.ie; Blake, Alan; Djara, Vladimir; O'Connell, Dan; Povey, Ian M.; Cherkaoui, Karim; Monaghan, Scott; Scully, Jim; Murphy, Richard; Hurley, Paul K.; Pemble, Martyn E.; Quinn, Aidan J., E-mail: aidan.quinn@tyndall.ie [Tyndall National Institute, University College Cork, Cork (Ireland)

    2015-01-01T23:59:59.000Z

    The authors report on the structural and electrical properties of TiN/Al{sub 2}O{sub 3}/TiN metal–insulator–metal (MIM) capacitor structures in submicron three-dimensional (3D) trench geometries with an aspect ratio of ?30. A simplified process route was employed where the three layers for the MIM stack were deposited using atomic layer deposition (ALD) in a single run at a process temperature of 250?°C. The TiN top and bottom electrodes were deposited via plasma-enhanced ALD using a tetrakis(dimethylamino)titanium precursor. 3D trench devices yielded capacitance densities of 36 fF/?m{sup 2} and quality factors >65 at low frequency (200?Hz), with low leakage current densities (<3 nA/cm{sup 2} at 1 V). These devices also show strong optical iridescence which, when combined with the covert embedded capacitance, show potential for system in package (SiP) anticounterfeiting applications.

  2. Suppressing the impact of a high tensor-to-scalar ratio on the temperature anisotropies

    E-Print Network [OSTI]

    Carlo R. Contaldi; Marco Peloso; Lorenzo Sorbo

    2014-07-05T23:59:59.000Z

    The BICEP2 collaboration has reported a strong B mode signal in the CMB polarization, which is well fit by a tensor-to-scalar ratio of r ~ 0.2. This is greater than the upper limit r data. The most advocated explanation involves a variation of n_s with scales (denoted as running) that has a magnitude significantly greater than the generic slow roll predictions. We instead study the possibility that the large scale temperature anisotropies are not enhanced because of a suppression of the scalar power at large scales. Such a situation can be achieved for instance by a sudden change of the speed of the inflaton (by about 14 %), and we show that it fits the temperature anisotropies and polarization data considerably better than a constant running (its chi^2 improves by ~ 7.5 over that of the constant running, at the cost of one more parameter). We also consider the possibility that the large scale temperature fluctuations are suppressed by an anti-correlation between tensor and scalar modes. Unfortunately, while such effect does affect the temperature fluctuations at large scales, it does not affect the temperature power spectrum and cannot, therefore, help in reconciling a large value of r with the limits from temperature fluctuations.

  3. Isothermal and shock compression of high density ammonium nitrate and ammonium perchlorate

    SciTech Connect (OSTI)

    Sandstrom, F.W.; Persson, P.A. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States); Olinger, B. [Los Alamos National Lab., NM (United States)

    1992-10-01T23:59:59.000Z

    Given the widespread use of ammonium nitrate (AN) and ammonium perchlorate (AP) for energetic materials applications, relatively little data is available regarding their behavior under shock loading. We have evaluated the shock Hugoniots of AN and AP at high initial density ({ge} 94% TMD) to pressures of approximately 20 GPa. We have used sound speed measurements, isothermal compfession X-ray diffraction experiments and shock loading experiments to further explore the behavior of the two materials at elevated pressures.

  4. Isothermal and shock compression of high density ammonium nitrate and ammonium perchlorate

    SciTech Connect (OSTI)

    Sandstrom, F.W.; Persson, P.A. (New Mexico Inst. of Mining and Technology, Socorro, NM (United States)); Olinger, B. (Los Alamos National Lab., NM (United States))

    1992-01-01T23:59:59.000Z

    Given the widespread use of ammonium nitrate (AN) and ammonium perchlorate (AP) for energetic materials applications, relatively little data is available regarding their behavior under shock loading. We have evaluated the shock Hugoniots of AN and AP at high initial density ([ge] 94% TMD) to pressures of approximately 20 GPa. We have used sound speed measurements, isothermal compfession X-ray diffraction experiments and shock loading experiments to further explore the behavior of the two materials at elevated pressures.

  5. Development of High Efficiency Clean Combustion Engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines

    SciTech Connect (OSTI)

    Marriott, Craig; Gonzalez, Manual; Russell, Durrett

    2011-06-30T23:59:59.000Z

    This report summarizes activities related to the revised STATEMENT OF PROJECT OBJECTIVES (SOPO) dated June 2010 for the Development of High-Efficiency Clean Combustion engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines (COOPERATIVE AGREEMENT NUMBER DE-FC26-05NT42415) project. In both the spark- (SI) and compression-ignition (CI) development activities covered in this program, the goal was to develop potential production-viable internal combustion engine system technologies that both reduce fuel consumption and simultaneously met exhaust emission targets. To be production-viable, engine technologies were also evaluated to determine if they would meet customer expectations of refinement in terms of noise, vibration, performance, driveability, etc. in addition to having an attractive business case and value. Prior to this activity, only proprietary theoretical / laboratory knowledge existed on the combustion technologies explored The research reported here expands and develops this knowledge to determine series-production viability. Significant SI and CI engine development occurred during this program within General Motors, LLC over more than five years. In the SI program, several engines were designed and developed that used both a relatively simple multi-lift valve train system and a Fully Flexible Valve Actuation (FFVA) system to enable a Homogeneous Charge Compression Ignition (HCCI) combustion process. Many technical challenges, which were unknown at the start of this program, were identified and systematically resolved through analysis, test and development. This report documents the challenges and solutions for each SOPO deliverable. As a result of the project activities, the production viability of the developed clean combustion technologies has been determined. At this time, HCCI combustion for SI engines is not considered production-viable for several reasons. HCCI combustion is excessively sensitive to control variables such as internal dilution level and charge temperature. As a result, HCCI combustion has limited robustness when variables exceed the required narrow ranges determined in this program. HCCI combustion is also not available for the entire range of production engine speeds and loads, (i.e., the dynamic range is limited). Thus, regular SI combustion must be employed for a majority of the full dynamic range of the engine. This degrades the potential fuel economy impact of HCCI combustion. Currently-available combustion control actuators for the simple valve train system engine do not have the authority for continuous air - fuel or torque control for managing the combustion mode transitions between SI and HCCI and thus, require further refinement to meet customer refinement expectations. HCCI combustion control sensors require further development to enable robust long-term HCCI combustion control. Finally, the added technologies required to effectively manage HCCI combustion such as electric cam phasers, central direct fuel injection, cylinder pressure sensing, high-flow exhaust gas recirculation system, etc. add excessive on-engine cost and complexity that erodes the production-viability business

  6. High Performance Mica-based Compressive Seals for Solid Oxide Fuel Cells -

    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 for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartmentInnovationHigh Flux Isotopethe Role

  7. High-Pressure Phase Equilibria of Ionic Liquids and Compressed Gases for Applications in Reactions and Absorption Refrigeration

    E-Print Network [OSTI]

    Ren, Wei

    2009-12-29T23:59:59.000Z

    for reactions and separations. However, without understanding the phase equilibrium, the kinetics results cannot be properly interpreted. This work also demonstrates that the absorption refrigeration system using ionic liquids and compressed gases in vehicles...

  8. Flexural support member having a high ratio of lateral-to-axial stiffness

    DOE Patents [OSTI]

    Haas, W.M.B.

    1983-06-23T23:59:59.000Z

    A convoluted flexible support structure is provided which is capable of supplying a lateral to axial spring rate in excess of 1000 to 1. A support member in the form of a steel disc having a specified number of rather large radius, concentric convolutions and a thickness in the range of from about 0.01 to 0.02 inch has an axial stiffness of about 50 pounds/inch while the lateral stiffness is about 100,000 pounds/inch. The support member may be used to support a vibration device where the lateral motion of the vibrator must be highly restricted while providing relatively free axial displacement of about +-0.25 inch.

  9. Compressive Creep Performance and High Temperature Dimensional Stability of Conventional Silica Refractories

    SciTech Connect (OSTI)

    Karakus, M.; Kirkland, T.P.; Liu, K.C.; Moore, R.E.; Pint, B.A.; Wereszczak, A.A.

    1999-03-01T23:59:59.000Z

    Furnace designers and refractory engineers recognize that optimized furnace superstructure design and refractory selection are needed as glass production furnaces are continually striving toward greater output and efficiencies. Harsher operating conditions test refractories to the limit, while changing production technology (such as the conversion to oxy-fuel from traditional air-fuel firing) can alter the way the materials perform. Refractories for both oxy- and air-fuel fired furnace superstructures are subjected to high temperatures during service that may cause them to excessively creep or subside if the refractory material is not creep resistant, or if it is subjected to high stress, or both. Furnace designers can ensure that superstructure structural integrity is maintained if the creep behavior of the refractory material is well understood and well represented by appropriate engineering creep models. Several issues limit the abilities of furnace designers to (1) choose the optimum refractory for their applications, (2) optimize the engineering design, or (3) predict the service mechanical integrity of their furnace superstructures. Published engineering creep data are essentially non-existent for almost all commercially available refractories used for glass furnace superstructures. The limited data that do exist are supplied by the various refractory suppliers. Unfortunately, these suppliers generally have different ways of conducting their mechanical testing and they also interpret and report their data differently; this makes it hard for furnace designers to draw fair comparisons between competing grades of candidate refractories. Furthermore, the refractory supplier's data are often not available in a form that can be readily used for furnace design and for the prediction and design of long-term structural integrity of furnace superstructures. With the aim of providing such comparable data, the US DOE's Office of Industrial Technology and its Advanced Industrial Materials program is sponsoring work to conduct creep testing and analysis on refractories of interest to the glass industry. An earlier stage of the project involved identifying which refractories to test and this is described elsewhere. Conventional silica was one such identified refractory category, and the present report describes the creep behavior of this class of refractories. To portray a more complete understanding of how these refractories perform at service temperatures, their fundamental corrosion resistances, dimensional stabilities, and microstructure were characterized as well.

  10. Material test machine for tension-compression tests at high temperature

    DOE Patents [OSTI]

    Cioletti, Olisse C. (Pittsburgh, PA)

    1988-01-01T23:59:59.000Z

    Apparatus providing a device for testing the properties of material specimens at high temperatures and pressures in controlled water chemistries includes, inter alia, an autoclave housing the specimen which is being tested. The specimen is connected to a pull rod which couples out of the autoclave to an external assembly which includes one or more transducers, a force balance chamber and a piston type actuator. The pull rod feeds through the force balance chamber and is compensated thereby for the pressure conditions existing within the autoclave and tending to eject the pull rod therefrom. The upper end of the push rod is connected to the actuator through elements containing a transducer comprising a linear variable differential transformer (LVDT). The housing and coil assembly of the LVDT is coupled to a tube which runs through a central bore of the pull rod into the autoclave where it is connected to one side of the specimen. The movable core of the LVDT is coupled to a stem which runs through the tube where it is then connected to the other side of the specimen through a coupling member. A transducer in the form of a load cell including one or more strain gages is located on a necked-down portion of the upper part of the pull rod intermediate the LVDT and force balance chamber.

  11. A novel apparatus for in situ compression of submicron structures and particles in a high resolution SEM

    SciTech Connect (OSTI)

    Romeis, S.; Paul, J.; Ziener, M.; Peukert, W. [Institute of Particle Technology, University of Erlangen-Nuremberg, Cauerstr. 4, 91058 Erlangen (Germany)

    2012-09-15T23:59:59.000Z

    We report on the development and characterization of a novel in situ manipulation device to perform stressing experiments on the submicron scale inside a high resolution field emission scanning electron microscope. The instrument comprises two main assembly groups: an upper part for positioning and moving a mounted probe and a force sensor as well as a specimen support as lower part. The upper part consists of a closed loop tripod piezoelectric scanner mounted on a self-locking coarse positioning stage. Two interlocked steel springs and a linear variable differential transformer measuring the springs' deflections compose the lower part of the instrument. This arrangement acts as force-sensor and sample support. In comparison to already well-established concepts a wide measuring range is covered by adjusting the spring constant between 30 N/m and 50000 N/m. Moreover, the new device offers striking advantages with respect to force calibration and sample deformation measurements. Force calibration is performed using the eigenfrequency of the force detection system directly inside the SEM. Deformation data are obtained with high accuracy by simultaneously recording displacements above and below the specimen. The detrimental apparatus compliance is determined, and the influence on measured data subsequently minimized: an easy to validate two-springs-in-series model is used for data correction. A force resolution in normal direction of 100 nN accompanied by a sample deformation resolution of 5 nm can be achieved with the instrument using an appropriate load cell stiffness. The capabilities and versatility of this instrument are exemplified by compression experiments performed on submicron amorphous silica particles.

  12. Electron Pulse Compression with a Practical Reflectron Design for Ultrafast Electron Diffraction

    E-Print Network [OSTI]

    Wang, Yihua

    2013-01-01T23:59:59.000Z

    Ultrafast electron diffraction (UED) is a powerful method for studying time-resolved structural changes. Currently, space charge induced temporal broadening prevents obtaining high brightness electron pulses with sub-100 fs durations limiting the range of phenomena that can be studied with this technique. We review the state of the the art of UED in this respect and propose a practical design for reflectron based pulse compression which utilizes only electro-static optics and has a tunable temporal focal point. Our simulation shows that this scheme is capable of compressing an electron pulse containing 100,000 electrons with 60:1 temporal compression ratio.

  13. Shock compression of precompressed deuterium

    SciTech Connect (OSTI)

    Armstrong, M R; Crowhurst, J C; Zaug, J M; Bastea, S; Goncharov, A F; Militzer, B

    2011-07-31T23:59:59.000Z

    Here we report quasi-isentropic dynamic compression and thermodynamic characterization of solid, precompressed deuterium over an ultrafast time scale (< 100 ps) and a microscopic length scale (< 1 {micro}m). We further report a fast transition in shock wave compressed solid deuterium that is consistent with the ramp to shock transition, with a time scale of less than 10 ps. These results suggest that high-density dynamic compression of hydrogen may be possible on microscopic length scales.

  14. High aspect ratio x-ray waveguide channels fabricated by e-beam lithography and wafer bonding

    SciTech Connect (OSTI)

    Neubauer, H.; Hoffmann, S.; Kanbach, M.; Haber, J.; Kalbfleisch, S.; Krüger, S. P.; Salditt, T., E-mail: tsaldit@gwdg.de [Institut für Röntgenphysik, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany)

    2014-06-07T23:59:59.000Z

    We report on the fabrication and characterization of hard x-ray waveguide channels manufactured by e-beam lithography, reactive ion etching and wafer bonding. The guiding layer consists of air or vacuum and the cladding material of silicon, which is favorable in view of minimizing absorption losses. The specifications for waveguide channels which have to be met in the hard x-ray range to achieve a suitable beam confinement in two orthogonal directions are extremely demanding. First, high aspect ratios up to 10{sup 6} have to be achieved between lateral structure size and length of the guides. Second, the channels have to be deeply embedded in material to warrant the guiding of the desired modes while absorbing all other (radiative) modes in the cladding material. We give a detailed report on device fabrication with the respective protocols and parameter optimization, the inspection and the optical characterization.

  15. Study of turbulent single-phase heat transfer and onset of nucleate boiling in high aspect ratio mini-channels to support the MITR LEU conversion/

    E-Print Network [OSTI]

    Forrest, Eric Christopher

    2014-01-01T23:59:59.000Z

    Heat transfer in high aspect ratio mini-channels has important applications for materials test reactors using plate-type fuel. These fuel plates typically possess coolant channels with hydraulic diameters on the order of ...

  16. Gas turbine power plant with supersonic shock compression ramps

    DOE Patents [OSTI]

    Lawlor, Shawn P. (Bellevue, WA); Novaresi, Mark A. (San Diego, CA); Cornelius, Charles C. (Kirkland, WA)

    2008-10-14T23:59:59.000Z

    A gas turbine engine. The engine is based on the use of a gas turbine driven rotor having a compression ramp traveling at a local supersonic inlet velocity (based on the combination of inlet gas velocity and tangential speed of the ramp) which compresses inlet gas against a stationary sidewall. The supersonic compressor efficiently achieves high compression ratios while utilizing a compact, stabilized gasdynamic flow path. Operated at supersonic speeds, the inlet stabilizes an oblique/normal shock system in the gasdynamic flow path formed between the rim of the rotor, the strakes, and a stationary external housing. Part load efficiency is enhanced by use of a lean pre-mix system, a pre-swirl compressor, and a bypass stream to bleed a portion of the gas after passing through the pre-swirl compressor to the combustion gas outlet. Use of a stationary low NOx combustor provides excellent emissions results.

  17. The FBI compression standard for digitized fingerprint images

    SciTech Connect (OSTI)

    Brislawn, C.M.; Bradley, J.N. [Los Alamos National Lab., NM (United States); Onyshczak, R.J. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Hopper, T. [Federal Bureau of Investigation, Washington, DC (United States)

    1996-10-01T23:59:59.000Z

    The FBI has formulated national standards for digitization and compression of gray-scale fingerprint images. The compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI standard, including the compliance testing process and the details of the first-generation encoder.

  18. Development of K-Basin High-Strength Homogeneous Sludge Simulants and Correlations Between Unconfined Compressive Strength and Shear Strength

    SciTech Connect (OSTI)

    Onishi, Yasuo; Baer, Ellen BK; Chun, Jaehun; Yokuda, Satoru T.; Schmidt, Andrew J.; Sande, Susan; Buchmiller, William C.

    2011-02-20T23:59:59.000Z

    K-Basin sludge will be stored in the Sludge Transport and Storage Containers (STSCs) at an interim storage location on Central Plateau before being treated and packaged for disposal. During the storage period, sludge in the STSCs may consolidate/agglomerate, potentially resulting in high-shear-strength material. The Sludge Treatment Project (STP) plans to use water jets to retrieve K-Basin sludge after the interim storage. STP has identified shear strength to be a key parameter that should be bounded to verify the operability and performance of sludge retrieval systems. Determining the range of sludge shear strength is important to gain high confidence that a water-jet retrieval system can mobilize stored K-Basin sludge from the STSCs. The shear strength measurements will provide a basis for bounding sludge properties for mobilization and erosion. Thus, it is also important to develop potential simulants to investigate these phenomena. Long-term sludge storage tests conducted by Pacific Northwest National Laboratory (PNNL) show that high-uranium-content K-Basin sludge can self-cement and form a strong sludge with a bulk shear strength of up to 65 kPa. Some of this sludge has 'paste' and 'chunks' with shear strengths of approximately 3-5 kPa and 380-770 kPa, respectively. High-uranium-content sludge samples subjected to hydrothermal testing (e.g., 185 C, 10 hours) have been observed to form agglomerates with a shear strength up to 170 kPa. These high values were estimated by measured unconfined compressive strength (UCS) obtained with a pocket penetrometer. Due to its ease of use, it is anticipated that a pocket penetrometer will be used to acquire additional shear strength data from archived K-Basin sludge samples stored at the PNNL Radiochemical Processing Laboratory (RPL) hot cells. It is uncertain whether the pocket penetrometer provides accurate shear strength measurements of the material. To assess the bounding material strength and potential for erosion, it is important to compare the measured shear strength to penetrometer measurements and to develop a correlation (or correlations) between UCS measured by a pocket penetrometer and direct shear strength measurements for various homogeneous and heterogeneous simulants. This study developed 11 homogeneous simulants, whose shear strengths vary from 4 to 170 kPa. With these simulants, we developed correlations between UCS measured by a Geotest E-280 pocket penetrometer and shear strength values measured by a Geonor H-60 hand-held vane tester and a more sophisticated bench-top unit, the Haake M5 rheometer. This was achieved with side-by-side measurements of the shear strength and UCS of the homogeneous simulants. The homogeneous simulants developed under this study consist of kaolin clay, plaster of Paris, and amorphous alumina CP-5 with water. The simulants also include modeling clay. The shear strength of most of these simulants is sensitive to various factors, including the simulant size, the intensity of mixing, and the curing time, even with given concentrations of simulant components. Table S.1 summarizes these 11 simulants and their shear strengths.

  19. Mixed RL-Huffman Encoding for Power Reduction and Data Compression in Scan Test

    E-Print Network [OSTI]

    Tehranipoor, Mohammad

    Mixed RL-Huffman Encoding for Power Reduction and Data Compression in Scan Test M. H. Tehranipour1 techniques to reduce test data volume, test pattern delivery time and power dissipation in scan test. This combination is especially effective when the ratio of don't cares in a test set is high which is a common case

  20. Application specific compression : final report.

    SciTech Connect (OSTI)

    Melgaard, David Kennett; Byrne, Raymond Harry; Myers, Daniel S.; Harrison, Carol D.; Lee, David S.; Lewis, Phillip J.; Carlson, Jeffrey J.

    2008-12-01T23:59:59.000Z

    With the continuing development of more capable data gathering sensors, comes an increased demand on the bandwidth for transmitting larger quantities of data. To help counteract that trend, a study was undertaken to determine appropriate lossy data compression strategies for minimizing their impact on target detection and characterization. The survey of current compression techniques led us to the conclusion that wavelet compression was well suited for this purpose. Wavelet analysis essentially applies a low-pass and high-pass filter to the data, converting the data into the related coefficients that maintain spatial information as well as frequency information. Wavelet compression is achieved by zeroing the coefficients that pertain to the noise in the signal, i.e. the high frequency, low amplitude portion. This approach is well suited for our goal because it reduces the noise in the signal with only minimal impact on the larger, lower frequency target signatures. The resulting coefficients can then be encoded using lossless techniques with higher compression levels because of the lower entropy and significant number of zeros. No significant signal degradation or difficulties in target characterization or detection were observed or measured when wavelet compression was applied to simulated and real data, even when over 80% of the coefficients were zeroed. While the exact level of compression will be data set dependent, for the data sets we studied, compression factors over 10 were found to be satisfactory where conventional lossless techniques achieved levels of less than 3.

  1. Reynolds and Mach Number Scaling in Stationary Compressible Turbulence Using Massively Parallel High Resolution Direct Numerical Simulations

    E-Print Network [OSTI]

    Jagannathan, Shriram

    2014-07-24T23:59:59.000Z

    on the acous- tic time scale leading to a simplified set of equations (Erlebacher et al., 1990; Sarkar et al., 1991). This leads to a flow regime known as low-Mach number quasi-isentropic regime, where the flow evolves only on acoustic time scale... and characterized by small dilatational fluctuations (Sagaut & Cambon, 2008). Under these conditions, Sarkar et al. (1991) observed an equipartition of energy between the compressible kinetic energy and potential energy due to the pressure. The phenomenon...

  2. air-fuel ratio control: Topics by E-print Network

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

    was performed to investigate the effects of air-fuel ratio, inlet boost pressure, hydrogen rich fuel reformate, and compression ratio on engine knock behavior. For each...

  3. JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 16, NO. 5, OCTOBER 2007 1025 Ultrathick and High-Aspect-Ratio Nickel

    E-Print Network [OSTI]

    Akin, Tayfun

    -Aspect-Ratio Nickel Microgyroscope Using EFAB Multilayer Additive Electroforming Said Emre Alper, Ilker Ender Ocak of a microgyroscope that has a 240-µm-thick multilayer electroformed-nickel structural mass and a lateral aspect ratio, demonstrating reliability of electroformed nickel of EFAB process. In addition, the mechanical quality factor

  4. Efficient Joins with Compressed Bitmap Indexes

    SciTech Connect (OSTI)

    Computational Research Division; Madduri, Kamesh; Wu, Kesheng

    2009-08-19T23:59:59.000Z

    We present a new class of adaptive algorithms that use compressed bitmap indexes to speed up evaluation of the range join query in relational databases. We determine the best strategy to process a join query based on a fast sub-linear time computation of the join selectivity (the ratio of the number of tuples in the result to the total number of possible tuples). In addition, we use compressed bitmaps to represent the join output compactly: the space requirement for storing the tuples representing the join of two relations is asymptotically bounded by min(h; n . cb), where h is the number of tuple pairs in the result relation, n is the number of tuples in the smaller of the two relations, and cb is the cardinality of the larger column being joined. We present a theoretical analysis of our algorithms, as well as experimental results on large-scale synthetic and real data sets. Our implementations are efficient, and consistently outperform well-known approaches for a range of join selectivity factors. For instance, our count-only algorithm is up to three orders of magnitude faster than the sort-merge approach, and our best bitmap index-based algorithm is 1.2x-80x faster than the sort-merge algorithm, for various query instances. We achieve these speedups by exploiting several inherent performance advantages of compressed bitmap indexes for join processing: an implicit partitioning of the attributes, space-efficiency, and tolerance of high-cardinality relations.

  5. Advances in compressible turbulent mixing

    SciTech Connect (OSTI)

    Dannevik, W.P.; Buckingham, A.C.; Leith, C.E. [eds.

    1992-01-01T23:59:59.000Z

    This volume includes some recent additions to original material prepared for the Princeton International Workshop on the Physics of Compressible Turbulent Mixing, held in 1988. Workshop participants were asked to emphasize the physics of the compressible mixing process rather than measurement techniques or computational methods. Actual experimental results and their meaning were given precedence over discussions of new diagnostic developments. Theoretical interpretations and understanding were stressed rather than the exposition of new analytical model developments or advances in numerical procedures. By design, compressibility influences on turbulent mixing were discussed--almost exclusively--from the perspective of supersonic flow field studies. The papers are arranged in three topical categories: Foundations, Vortical Domination, and Strongly Coupled Compressibility. The Foundations category is a collection of seminal studies that connect current study in compressible turbulent mixing with compressible, high-speed turbulent flow research that almost vanished about two decades ago. A number of contributions are included on flow instability initiation, evolution, and transition between the states of unstable flow onset through those descriptive of fully developed turbulence. The Vortical Domination category includes theoretical and experimental studies of coherent structures, vortex pairing, vortex-dynamics-influenced pressure focusing. In the Strongly Coupled Compressibility category the organizers included the high-speed turbulent flow investigations in which the interaction of shock waves could be considered an important source for production of new turbulence or for the enhancement of pre-existing turbulence. Individual papers are processed separately.

  6. Demonstration/Development of Reactivity Controlled Compression...

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

    DemonstrationDevelopment of Reactivity Controlled Compression Ignition (RCCI) Combustion for High Efficiency, Low Emissions Vehicle Applications Dr. Rolf Reitz Wisconsin Engine...

  7. Best compression: Reciprocating or rotary?

    SciTech Connect (OSTI)

    Cahill, C.

    1997-07-01T23:59:59.000Z

    A compressor is a device used to increase the pressure of a compressible fluid. The inlet pressure can vary from a deep vacuum to a high positive pressure. The discharge pressure can range from subatmospheric levels to tens of thousands of pounds per square inch. Compressors come in numerous forms, but for oilfield applications there are two primary types, reciprocating and rotary. Both reciprocating and rotary compressors are grouped in the intermittent mode of compression. Intermittent is cyclic in nature, in that a specific quantity of gas is ingested by the compressor, acted upon and discharged before the cycle is repeated. Reciprocating compression is the most common form of compression used for oilfield applications. Rotary screw compressors have a long history but are relative newcomers to oilfield applications. The rotary screw compressor-technically a helical rotor compressor-dates back to 1878. That was when the first rotary screw was manufactured for the purpose of compressing air. Today thousands of rotary screw compression packages are being used throughout the world to compress natural gas.

  8. Fabrication of nanowires with high aspect ratios utilized by dry etching with SF6:C4F8 and self-limiting thermal oxidation on Si substrate

    E-Print Network [OSTI]

    Fabrication of nanowires with high aspect ratios utilized by dry etching with SF6:C4F8 and self-RIE with a continuous processing gas mixture of fluorine-based SF6:C4F8 combined with a thermal oxidation technique

  9. Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    , California 92617, United States Chemical and Materials Sciences Division and § Environmental Molecular. A correlation was found between the ratio of the ionization efficiencies in the positive (+) and negative identification of the aerosol constituents. INTRODUCTION Due to the molecular complexity inherent to secondary

  10. Summary of Compression Testing of U-10Mo

    SciTech Connect (OSTI)

    Nyberg, Eric A.; Joshi, Vineet V.; Lavender, Curt A.; Burkes, Douglas

    2012-10-31T23:59:59.000Z

    The mechanical properties of depleted uranium plus 10 weight percent molybdenum alloy have been evaluated by high temperature compression testing.

  11. Chapter 22: Compressed Air Evaluation Protocol

    SciTech Connect (OSTI)

    Benton, N.

    2014-11-01T23:59:59.000Z

    Compressed-air systems are used widely throughout industry for many operations, including pneumatic tools, packaging and automation equipment, conveyors, and other industrial process operations. Compressed-air systems are defined as a group of subsystems composed of air compressors, air treatment equipment, controls, piping, pneumatic tools, pneumatically powered machinery, and process applications using compressed air. A compressed-air system has three primary functional subsystems: supply, distribution, and demand. Air compressors are the primary energy consumers in a compressed-air system and are the primary focus of this protocol. The two compressed-air energy efficiency measures specifically addressed in this protocol are: high-efficiency/variable speed drive (VSD) compressor replacing modulating compressor; compressed-air leak survey and repairs. This protocol provides direction on how to reliably verify savings from these two measures using a consistent approach for each.

  12. J.E. Menard -IEA Workshop 59 -Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamaks 1 Ideal MHD stability scaling with

    E-Print Network [OSTI]

    -State Tokamaks 8 · Highest-N shots are H-mode ­ H-mode profiles N 3.5 for optimized n=1 no-wall limit · 10 with at = 0.3 ­ High essential for highest stable T N limit increases from 3.5 to 5.5 with increasing Workshop 59 - Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamaks 2 Outline

  13. Compressed gas fuel storage system

    DOE Patents [OSTI]

    Wozniak, John J. (Columbia, MD); Tiller, Dale B. (Lincoln, NE); Wienhold, Paul D. (Baltimore, MD); Hildebrand, Richard J. (Edgemere, MD)

    2001-01-01T23:59:59.000Z

    A compressed gas vehicle fuel storage system comprised of a plurality of compressed gas pressure cells supported by shock-absorbing foam positioned within a shape-conforming container. The container is dimensioned relative to the compressed gas pressure cells whereby a radial air gap surrounds each compressed gas pressure cell. The radial air gap allows pressure-induced expansion of the pressure cells without resulting in the application of pressure to adjacent pressure cells or physical pressure to the container. The pressure cells are interconnected by a gas control assembly including a thermally activated pressure relief device, a manual safety shut-off valve, and means for connecting the fuel storage system to a vehicle power source and a refueling adapter. The gas control assembly is enclosed by a protective cover attached to the container. The system is attached to the vehicle with straps to enable the chassis to deform as intended in a high-speed collision.

  14. Nuclear Instruments and Methods in Physics Research A 577 (2007) 223230 Neutralized drift compression experiments with a

    E-Print Network [OSTI]

    Gilson, Erik

    2007-01-01T23:59:59.000Z

    .: +1 510 495 2616; fax: +1 510 486 5392. E-mail address: pkroy@lbl.gov (P.K. Roy). #12;ratio, the ratio compression experiments with a high-intensity ion beam P.K. Roya,Ã, S.S. Yua , W.L. Waldrona , A. Andersa , D. Bacaa , J.J. Barnardb , F.M. Bienioseka , J. Colemana , R.C. Davidsonc , P.C. Efthimionc , S. Eylona , A

  15. Kalman-filtered compressive sensing for high resolution estimation of anthropogenic greenhouse gas emissions from sparse measurements.

    SciTech Connect (OSTI)

    Ray, Jaideep; Lee, Jina; Lefantzi, Sophia; Yadav, Vineet [Carnegie Institution for Science, Stanford, CA; Michalak, Anna M. [Carnegie Institution for Science, Stanford, CA; van Bloemen Waanders, Bart Gustaaf [Sandia National Laboratories, Albuquerque NM; McKenna, Sean Andrew [IBM Research, Mulhuddart, Dublin, Ireland

    2013-09-01T23:59:59.000Z

    The estimation of fossil-fuel CO2 emissions (ffCO2) from limited ground-based and satellite measurements of CO2 concentrations will form a key component of the monitoring of treaties aimed at the abatement of greenhouse gas emissions. The limited nature of the measured data leads to a severely-underdetermined estimation problem. If the estimation is performed at fine spatial resolutions, it can also be computationally expensive. In order to enable such estimations, advances are needed in the spatial representation of ffCO2 emissions, scalable inversion algorithms and the identification of observables to measure. To that end, we investigate parsimonious spatial parameterizations of ffCO2 emissions which can be used in atmospheric inversions. We devise and test three random field models, based on wavelets, Gaussian kernels and covariance structures derived from easily-observed proxies of human activity. In doing so, we constructed a novel inversion algorithm, based on compressive sensing and sparse reconstruction, to perform the estimation. We also address scalable ensemble Kalman filters as an inversion mechanism and quantify the impact of Gaussian assumptions inherent in them. We find that the assumption does not impact the estimates of mean ffCO2 source strengths appreciably, but a comparison with Markov chain Monte Carlo estimates show significant differences in the variance of the source strengths. Finally, we study if the very different spatial natures of biogenic and ffCO2 emissions can be used to estimate them, in a disaggregated fashion, solely from CO2 concentration measurements, without extra information from products of incomplete combustion e.g., CO. We find that this is possible during the winter months, though the errors can be as large as 50%.

  16. OPTIMAL CONTROL EXPERIMENTATION OF COMPRESSION TRAJECTORIES FOR A LIQUID PISTON AIR COMPRESSOR

    E-Print Network [OSTI]

    Li, Perry Y.

    efficiency for a given compression time and compression ratio. The main part of the heat transfer model profile for a general heat transfer model. While the results show a good improvement both in the lumped

  17. Surface compression *

    E-Print Network [OSTI]

    89-0455), and the Army High Performance Computing Research Center. Correspondence to: RA. DeVore, Department of Mathematics, University of South

  18. The compressive response of porcine adipose tissue from low to high strain rate Kerstyn Comley, Norman Fleck*

    E-Print Network [OSTI]

    Fleck, Norman A.

    at high strain rates (1000 sÀ1 e5700 sÀ1 ) were conducted with a split Hopkinson pressure bar (SHPB) using polycarbonate bars. Over the full range of strain rate from quasi-static to high strain rate, the magnitude pressure bar (SHPB) with polycarbonate bars (PC). It is demon- strated that a one dimensional Ogden model

  19. High Resolution Imaging of the Anomalous Flux-Ratio Gravitational Lens System CLASS B2045+265: Dark Or Luminous Satellites?

    SciTech Connect (OSTI)

    McKean, J.P.; Koopmans, L.V.E.; Flack, C.E.; Fassnacht, C.D.; Thompson, D.; Matthews, K.; Blandford, R.D.; Readhead, A.C.S.; Soifer, B.T.; /UC, Davis /Bonn, Max Planck

    2006-11-10T23:59:59.000Z

    The existence of flux-ratio anomalies between fold and cusp images in galaxy-scale strong-lens systems has led to an interpretation based on the presence of a high mass-fraction of cold-dark-matter (CDM) substructures around galaxies, as predicted by numerical N-body simulations. These substructures can cause large perturbations of the image magnifications, leading to changes in the image flux ratios. The flux-ratio anomaly is particularly evident in the radio-loud quadruple gravitational lens system CLASS B2045+265. In this paper, new high-resolution radio, optical, and infrared imaging of B2045+265 is presented which sheds more light on this anomaly and its possible causes. First, deep Very Long Baseline Array observations show very compact images, possibly with a hint of a jet, but with no evidence for differential scattering or scatter broadening. Hence, the flux-ratio anomaly is unlikely to be caused by refractive scattering in either the Milky Way or the lens galaxy. Second, optical and infrared observations with the Hubble Space Telescope and through Adaptive-Optics imaging with the W. M. Keck Telescope, show a previously undiscovered object--interpreted as a (tidally disrupted) dwarf satellite based on its colors and slight extension--between the main lens galaxy and the three anomalous flux-ratio images. Third, color variations in the early-type lens galaxy indicate recent star-formation, possibly the result of secondary infall of gas-rich satellites. A population of young galaxies around the lens system could explain the previously discovered strong [O II] emission. However, spiral structure and/or normal star formation in the lens galaxy cannot be excluded. In light of these new data, we propose a lens model for the system, including the observed dwarf satellite, which reproduces all positional and flux-ratio constraints, without the need for additional CDM substructure. Although the model is peculiar in that the dwarf galaxy must be highly flattened, the model is very similar to recently proposed mass models based on high-order multipole expansions.

  20. Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols

    SciTech Connect (OSTI)

    Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

    2012-07-02T23:59:59.000Z

    The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

  1. High flux symmetry of the spherical hohlraum with octahedral 6LEHs at the hohlraum-to-capsule radius ratio of 5.14

    SciTech Connect (OSTI)

    Lan, Ke; Liu, Jie; He, Xian-Tu [Institute of Applied Physics and Computational Mathematics, Beijing, 100088 (China) [Institute of Applied Physics and Computational Mathematics, Beijing, 100088 (China); Center for Applied Physics and Technology, Peking University, Beijing, 100871 (China); Lai, Dongxian; Zheng, Wudi [Institute of Applied Physics and Computational Mathematics, Beijing, 100088 (China)] [Institute of Applied Physics and Computational Mathematics, Beijing, 100088 (China)

    2014-01-15T23:59:59.000Z

    We propose a spherical hohlraum with octahedral six laser entrance holes at a specific hohlraum-to-capsule radius ratio of 5.14 for inertial fusion study, which has robust high symmetry during the capsule implosion and low backscatter without supplementary technology. To produce an ignition radiation pulse of 300?eV, it needs 1.5?MJ absorbed laser energy in such a golden octahedral hohlraum, about 30% more than a traditional cylinder. Nevertheless, it is worth for a high symmetry and low backscatter. The proposed octahedral hohlraum is also flexible and can be applicable to diverse inertial fusion drive approaches.

  2. Compressed Air Supply Efficiency

    E-Print Network [OSTI]

    Joseph, B.

    2004-01-01T23:59:59.000Z

    This project, under contract from California Energy Commission, developed the CASE (Compressed Air Supply Efficiency) Index as a stand-alone value for compressor central plant efficiency. This Index captures the overall efficiency of a compressed...

  3. Sequential Compressed Sensing

    E-Print Network [OSTI]

    Malioutov, Dmitry M.

    Compressed sensing allows perfect recovery of sparse signals (or signals sparse in some basis) using only a small number of random measurements. Existing results in compressed sensing literature have focused on characterizing ...

  4. Compressed Air Supply Efficiency 

    E-Print Network [OSTI]

    Joseph, B.

    2004-01-01T23:59:59.000Z

    COMPRESSED AIR SUPPLY EFFICENCY Babu Joseph, Ph.D., P.E. Engineer Southern California Edison Irwindale, CA ABSTRACT This project, under contract from California Energy Commission, developed the CASE (Compressed Air Supply Efficiency...

  5. Consider Compressed Combustion

    E-Print Network [OSTI]

    Crowther, R. H.

    1982-01-01T23:59:59.000Z

    sharing systems employing gas turbines. Incentives for compressed combustion have been explored and are presented in this discussion....

  6. Compressed gas manifold

    DOE Patents [OSTI]

    Hildebrand, Richard J. (Edgemere, MD); Wozniak, John J. (Columbia, MD)

    2001-01-01T23:59:59.000Z

    A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.

  7. Compressive behavior of fine sand.

    SciTech Connect (OSTI)

    Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

    2010-04-01T23:59:59.000Z

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  8. Hydrogen Delivery Liquefaction and Compression

    Broader source: Energy.gov [DOE]

    Hydrogen Delivery Liquefaction and Compression - Overview of commercial hydrogen liquefaction and compression and opportunities to improve efficiencies and reduce cost.

  9. Influence of Ar/Kr ratio and pulse parameters in a Cr-N high power pulse magnetron sputtering process on plasma and coating properties

    SciTech Connect (OSTI)

    Bobzin, Kirsten; Bagcivan, Nazlim; Theiß, Sebastian; Trieschmann, Jan; Brugnara, Ricardo Henrique, E-mail: brugnara@iot.rwth-aachen.de [Surface Engineering Institute, RWTH Aachen University, D-52072 Aachen (Germany); Preissing, Sven; Hecimovic, Ante [Institute of Experimental Physics II, Research Department Plasmas with Complex Interactions, Ruhr-University Bochum, D- 44780 Bochum (Germany)

    2014-03-15T23:59:59.000Z

    Krypton is sometimes used in physical vapor deposition processes due to its greater atomic mass and size compared to argon, which leads to a lower gas incorporation and may have beneficial effects on kinetics of the coating growth. In this paper, the authors investigate the plasma composition and properties of deposited high power pulse magnetron sputtering Cr-N coatings for discharges with various Ar/Kr ratios and for various pulse lengths of 40??s, 80??s, and 200??s, keeping the average discharge power constant. The results show that an addition of Kr influences the discharge process by altering the ignition and peak values of the discharge current. This influences the metal ion generation and growth conditions on the substrate by reducing the nucleation site densities, leading to a predominantly columnar grow. However, the deposition rate is highest for an Ar/Kr ratio of 120/80. The integral of the metal ion and atom emission exhibits the same trend, having a maximum for Ar/Kr ratio of 120/80. By decreasing the pulse length, the deposition rate of coatings decreases, while the hardness increases.

  10. Coupled Orbit-Attitude Dynamics of High Area-to-Mass Ratio (HAMR) Objects: Influence of Solar Radiation Pressure, Earth's Shadow and the Visibility in Light Curves

    E-Print Network [OSTI]

    Frueh, Carolin; Kelecy, Thomas

    2013-01-01T23:59:59.000Z

    The orbital and attitude dynamics of uncontrolled Earth orbiting objects are perturbed by a variety of sources. In research, emphasis has been put on operational space vehicles. Operational satellites typically have a relatively compact shape, and hence, a low area-to-mass ratio (AMR), and are in most cases actively or passively attitude stabilized. This enables one to treat the orbit and attitude propagation as decoupled problems, and in many cases the attitude dynamics can be neglected completely. The situation is different for space debris objects, which are in an uncontrolled attitude state. Furthermore, the assumption that a steady-state attitude motion can be averaged over data reduction intervals may no longer be valid. Additionally, a subset of the debris objects have significantly high area-to-mass ratio values, resulting in highly perturbed orbits, e.g. by solar radiation pressure, even if a stable AMR value is assumed. This assumption implies a steady-state attitude such that the average cross-sect...

  11. Sparsity-based optimization of two lifting-based wavelet transforms for semi-regular mesh compression

    E-Print Network [OSTI]

    Boyer, Edmond

    , and consequently high compression performances. In computer graphics, the compact representation is not the sole

  12. Objective index of image fidelity for JPEG2000 compressed body CT images

    SciTech Connect (OSTI)

    Kim, Kil Joong; Lee, Kyoung Ho; Kang, Heung-Sik; Kim, So Yeon; Kim, Young Hoon; Kim, Bohyoung; Seo, Jinwook; Mantiuk, Rafal [Department of Radiation Applied Life Science, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul, 110-744 (Korea, Republic of); Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Institute of Radiation Medicine, and Seoul National University Medical Research Center, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggido, 463-707 (Korea, Republic of); School of Computer Science and Engineering, Seoul National University, 599 Gwanak-Ro, Gwanak-Gu, Seoul, 151-744 (Korea, Republic of); Department of Computer Science, University of British Columbia, 201-2366 Main Mall, Vancouver, British Columbia V6T 1Z4 (Canada)

    2009-07-15T23:59:59.000Z

    Compression ratio (CR) has been the de facto standard index of compression level for medical images. The aim of the study is to evaluate the CR, peak signal-to-noise ratio (PSNR), and a perceptual quality metric (high-dynamic range visual difference predictor HDR-VDP) as objective indices of image fidelity for Joint Photographic Experts Group (JPEG) 2000 compressed body computed tomography (CT) images, from the viewpoint of visually lossless compression approach. A total of 250 body CT images obtained with five different scan protocols (5-mm-thick abdomen, 0.67-mm-thick abdomen, 5-mm-thick lung, 0.67-mm-thick lung, and 5-mm-thick low-dose lung) were compressed to one of five CRs (reversible, 6:1, 8:1, 10:1, and 15:1). The PSNR and HDR-VDP values were calculated for the 250 pairs of the original and compressed images. By alternately displaying an original and its compressed image on the same monitor, five radiologists independently determined if the pair was distinguishable or indistinguishable. The kappa statistic for the interobserver agreement among the five radiologists' responses was 0.70. According to the radiologists' responses, the number of distinguishable image pairs tended to significantly differ among the five scan protocols at 6:1-10:1 compressions (Fisher-Freeman-Halton exact tests). Spearman's correlation coefficients between each of the CR, PSNR, and HDR-VDP and the number of radiologists who responded as distinguishable were 0.72, -0.77, and 0.85, respectively. Using the radiologists' pooled responses as the reference standards, the areas under the receiver-operating-characteristic curves for the CR, PSNR, and HDR-VDP were 0.87, 0.93, and 0.97, respectively, showing significant differences between the CR and PSNR (p=0.04), or HDR-VDP (p<0.001), and between the PSNR and HDR-VDP (p<0.001). In conclusion, the CR is less suitable than the PSNR or HDR-VDP as an objective index of image fidelity for JPEG2000 compressed body CT images. The HDR-VDP is more promising than the PSNR as such an index.

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

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

    Dv,0.5 Combustion Chamber Photo Combustion Chamber Photo Test Fuels Test Fuels Diesel Fuel (Typical US) Gasoline (Pump Grade 87 RON) Fischer Tropsch Naphtha Blends of...

  14. Benefits and Drawbacks of Compression Ratio Reduction in PCCI Combustion

    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 Your Destiny: The FutureCommentsEnergy Christopher Smith,CommercePolicy

  15. Variable compression ratio device for internal combustion engine

    DOE Patents [OSTI]

    Maloney, Ronald P.; Faletti, James J.

    2004-03-23T23:59:59.000Z

    An internal combustion engine, particularly suitable for use in a work machine, is provided with a combustion cylinder, a cylinder head at an end of the combustion cylinder and a primary piston reciprocally disposed within the combustion cylinder. The cylinder head includes a secondary cylinder and a secondary piston reciprocally disposed within the secondary cylinder. An actuator is coupled with the secondary piston for controlling the position of the secondary piston dependent upon the position of the primary piston. A communication port establishes fluid flow communication between the combustion cylinder and the secondary cylinder.

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

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

    Simulation Results - Europe 14 1 0 0 1 1 0 1 2 0 1 3 0 1 4 0 1 5 0 1 6 0 CO 2 Emission gkm Base fixed CR NEDC -5.6% -5.9% -5.7% -5.8% -5.5% WLTP -5.1% -5.2% -4.5% -5.0%...

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

    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 Your Destiny:RevisedAdvisoryStandardGeneration |10 DOEGoalsEvaluation11of Energy Variable

  18. THE ABUNDANCE, ORTHO/PARA RATIO, AND DEUTERATION OF WATER IN THE HIGH-MASS STAR-FORMING REGION NGC 6334 I

    SciTech Connect (OSTI)

    Emprechtinger, M.; Lis, D. C.; Monje, R. R. [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States)] [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States); Rolffs, R.; Schilke, P. [Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany)] [Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany); Comito, C. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)] [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Ceccarelli, C. [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France)] [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Neufeld, D. A. [Department of Physics and Astronomy Johns Hopkins University, Baltimore, MD 21218 (United States)] [Department of Physics and Astronomy Johns Hopkins University, Baltimore, MD 21218 (United States); Van der Tak, F. F. S., E-mail: dcl@caltech.edu [SRON Netherlands Institute for Space Research and Kapteyn Astronomical Institute, University of Groningen, Groningen (Netherlands)

    2013-03-01T23:59:59.000Z

    We present Herschel/HIFI observations of 30 transitions of water isotopologues toward the high-mass star-forming region NGC 6334 I. The line profiles of H{sup 16} {sub 2}O, H{sup 17} {sub 2}O, H{sup 18} {sub 2}O, and HDO show a complex pattern of emission and absorption components associated with the embedded hot cores, a lower-density envelope, two outflow components, and several foreground clouds, some associated with the NGC 6334 complex, others seen in projection against the strong continuum background of the source. Our analysis reveals an H{sub 2}O ortho/para ratio of 3 {+-} 0.5 in the foreground clouds, as well as the outflow. The water abundance varies from {approx}10{sup -8} in the foreground clouds and the outer envelope to {approx}10{sup -6} in the hot core. The hot core abundance is two orders of magnitude below the chemical model predictions for dense, warm gas, but within the range of values found in other Herschel/HIFI studies of hot cores and hot corinos. This may be related to the relatively low gas and dust temperature ({approx}100 K), or time-dependent effects, resulting in a significant fraction of water molecules still locked up in dust grain mantles. The HDO/H{sub 2}O ratio in NGC 6334 I, {approx}2 Multiplication-Sign 10{sup -4}, is also relatively low, but within the range found in other high-mass star-forming regions.

  19. ADVANCED RECIPROCATING COMPRESSION TECHNOLOGY (ARCT)

    SciTech Connect (OSTI)

    Danny M. Deffenbaugh; Klaus Brun; Ralph E. Harris; J. Pete Harrell; Robert J. Mckee; J. Jeffrey Moore; Steven J. Svedeman; Anthony J. Smalley; Eugene L. Broerman; Robert A Hart; Marybeth G. Nored; Ryan S. Gernentz; Shane P. Siebenaler

    2005-12-01T23:59:59.000Z

    The U.S. natural gas pipeline industry is facing the twin challenges of increased flexibility and capacity expansion. To meet these challenges, the industry requires improved choices in gas compression to address new construction and enhancement of the currently installed infrastructure. The current fleet of installed reciprocating compression is primarily slow-speed integral machines. Most new reciprocating compression is and will be large, high-speed separable units. The major challenges with the fleet of slow-speed integral machines are: limited flexibility and a large range in performance. In an attempt to increase flexibility, many operators are choosing to single-act cylinders, which are causing reduced reliability and integrity. While the best performing units in the fleet exhibit thermal efficiencies between 90% and 92%, the low performers are running down to 50% with the mean at about 80%. The major cause for this large disparity is due to installation losses in the pulsation control system. In the better performers, the losses are about evenly split between installation losses and valve losses. The major challenges for high-speed machines are: cylinder nozzle pulsations, mechanical vibrations due to cylinder stretch, short valve life, and low thermal performance. To shift nozzle pulsation to higher orders, nozzles are shortened, and to dampen the amplitudes, orifices are added. The shortened nozzles result in mechanical coupling with the cylinder, thereby, causing increased vibration due to the cylinder stretch mode. Valve life is even shorter than for slow speeds and can be on the order of a few months. The thermal efficiency is 10% to 15% lower than slow-speed equipment with the best performance in the 75% to 80% range. The goal of this advanced reciprocating compression program is to develop the technology for both high speed and low speed compression that will expand unit flexibility, increase thermal efficiency, and increase reliability and integrity. Retrofit technologies that address the challenges of slow-speed integral compression are: (1) optimum turndown using a combination of speed and clearance with single-acting operation as a last resort; (2) if single-acting is required, implement infinite length nozzles to address nozzle pulsation and tunable side branch absorbers for 1x lateral pulsations; and (3) advanced valves, either the semi-active plate valve or the passive rotary valve, to extend valve life to three years with half the pressure drop. This next generation of slow-speed compression should attain 95% efficiency, a three-year valve life, and expanded turndown. New equipment technologies that address the challenges of large-horsepower, high-speed compression are: (1) optimum turndown with unit speed; (2) tapered nozzles to effectively reduce nozzle pulsation with half the pressure drop and minimization of mechanical cylinder stretch induced vibrations; (3) tunable side branch absorber or higher-order filter bottle to address lateral piping pulsations over the entire extended speed range with minimal pressure drop; and (4) semi-active plate valves or passive rotary valves to extend valve life with half the pressure drop. This next generation of large-horsepower, high-speed compression should attain 90% efficiency, a two-year valve life, 50% turndown, and less than 0.75 IPS vibration. This program has generated proof-of-concept technologies with the potential to meet these ambitious goals. Full development of these identified technologies is underway. The GMRC has committed to pursue the most promising enabling technologies for their industry.

  20. NOVEL CONCEPTS FOR THE COMPRESSION OF LARGE VOLUMES OF CARBON DIOXIDE-PHASE III

    SciTech Connect (OSTI)

    Moore, J. Jeffrey; Allison, Timothy; Evans, Neal; Moreland, Brian; Hernandez, Augusto; Day, Meera; Ridens, Brandon

    2014-06-30T23:59:59.000Z

    In the effort to reduce the release of CO2 greenhouse gases to the atmosphere, sequestration of CO2 from Integrated Gasification Combined Cycle (IGCC) and Oxy-Fuel power plants is being pursued. This approach, however, requires significant compression power to boost the pressure to typical pipeline levels. The penalty can be as high as 8-12% on a typical IGCC plant. The goal of this research is to reduce this penalty through novel compression concepts and integration with existing IGCC processes. The primary objective of the study of novel CO2 compression concepts is to reliably boost the pressure of CO2 to pipeline pressures with the minimal amount of energy required. Fundamental thermodynamics were studied to explore pressure rise in both liquid and gaseous states. For gaseous compression, the project investigated novel methods to compress CO2 while removing the heat of compression internal to the compressor. The highpressure ratio, due to the delivery pressure of the CO2 for enhanced oil recovery, results in significant heat of compression. Since less energy is required to boost the pressure of a cooler gas stream, both upstream and inter-stage cooling is desirable. While isothermal compression has been utilized in some services, it has not been optimized for the IGCC environment. Phase I of this project determined the optimum compressor configuration and developed technology concepts for internal heat removal. Other compression options using liquefied CO2 and cryogenic pumping were explored as well. Preliminary analysis indicated up to a 35% reduction in power is possible with the new concepts being considered. In the Phase II program, two experimental test rigs were developed to investigate the two concepts further. A new pump loop facility was constructed to qualify a cryogenic turbopump for use on liquid CO2. Also, an internally cooled compressor diaphragm was developed and tested in a closed loop compressor facility using CO2. Both test programs successfully demonstrated good performance and mechanical behavior. In Phase III, a pilot compression plant consisting of a multi-stage centrifugal compressor with cooled diaphragm technology has been designed, constructed, and tested. Comparative testing of adiabatic and cooled tests at equivalent inlet conditions shows that the cooled diaphragms reduce power consumption by 3-8% when the compressor is operated as a back-to-back unit and by up to 9% when operated as a straight-though compressor with no intercooler. The power savings, heat exchanger effectiveness, and temperature drops for the cooled diaphragm were all slightly higher than predicted values but showed the same trends.

  1. Compressed air energy storage system

    DOE Patents [OSTI]

    Ahrens, Frederick W. (Naperville, IL); Kartsounes, George T. (Naperville, IL)

    1981-01-01T23:59:59.000Z

    An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

  2. LAPPED TRANSFORMS COMPRESSION

    E-Print Network [OSTI]

    de Queiroz, Ricardo L.

    Chapter 6 LAPPED TRANSFORMS FOR IMAGE COMPRESSION Ricardo L. de Queiroz Digital Imaging Technology aspects of lapped transforms and their applications to image compression. It is a subject that has been extensively studied mainly because lapped transforms are closely related to filter banks, wavelets, and time

  3. Fundamentals of Compressed Air Systems

    Office of Energy Efficiency and Renewable Energy (EERE)

    Find out how a compressed air system works and the benefits of optimal compressed air system performance. This initial class demonstrates how to compute the current cost of your plant's compressed...

  4. Resonant tunneling with high peak to valley current ratio in SiO{sub 2}/nc-Si/SiO{sub 2} multi-layers at room temperature

    SciTech Connect (OSTI)

    Chen, D. Y., E-mail: cdy7659@126.com [Department of Physics, Nanjing National Laboratory of Microstructures and Key Laboratory of Advanced Photonic and Electronic, materials, Nanjing University, Nanjing 210093 (China); Nanjing University of posts and Telecommunications, Nanjing 210046 (China); Sun, Y.; He, Y. J. [Nanjing University of posts and Telecommunications, Nanjing 210046 (China); Xu, L.; Xu, J. [Department of Physics, Nanjing National Laboratory of Microstructures and Key Laboratory of Advanced Photonic and Electronic, materials, Nanjing University, Nanjing 210093 (China)

    2014-01-28T23:59:59.000Z

    We have investigated carrier transport in SiO{sub 2}/nc-Si/SiO{sub 2} multi-layers by room temperature current-voltage measurements. Resonant tunneling signatures accompanied by current peaks are observed. Carrier transport in the multi-layers were analyzed by plots of ln(I/V{sup 2}) as a function of 1/V and ln(I) as a function of V{sup 1/2}. Results suggest that besides films quality, nc-Si and barrier sub-layer thicknesses are important parameters that restrict carrier transport. When thicknesses are both small, direct tunneling dominates carrier transport, resonant tunneling occurs only at certain voltages and multi-resonant tunneling related current peaks can be observed but with peak to valley current ratio (PVCR) values smaller than 1.5. When barrier thickness is increased, trap-related and even high field related tunneling is excited, causing that multi-current peaks cannot be observed clearly, only one current peak with higher PVCR value of 7.7 can be observed. While if the thickness of nc-Si is large enough, quantum confinement is not so strong, a broad current peak with PVCR value as high as 60 can be measured, which may be due to small energy difference between the splitting energy levels in the quantum dots of nc-Si. Size distribution in a wide range may cause un-controllability of the peak voltages.

  5. Modeling Compressed Turbulence

    SciTech Connect (OSTI)

    Israel, Daniel M. [Los Alamos National Laboratory

    2012-07-13T23:59:59.000Z

    From ICE to ICF, the effect of mean compression or expansion is important for predicting the state of the turbulence. When developing combustion models, we would like to know the mix state of the reacting species. This involves density and concentration fluctuations. To date, research has focused on the effect of compression on the turbulent kinetic energy. The current work provides constraints to help development and calibration for models of species mixing effects in compressed turbulence. The Cambon, et al., re-scaling has been extended to buoyancy driven turbulence, including the fluctuating density, concentration, and temperature equations. The new scalings give us helpful constraints for developing and validating RANS turbulence models.

  6. Experimental investigation of piston heat transfer under conventional diesel and reactivity-controlled compression ignition combustion regimes

    SciTech Connect (OSTI)

    Splitter, Derek A [ORNL; Hendricks, Terry Lee [Sandia National Laboratories (SNL); Ghandhi, Jaal B [University of Wisconsin

    2014-01-01T23:59:59.000Z

    The piston of a heavy-duty single-cylinder research engine was instrumented with 11 fast-response surface thermocouples, and a commercial wireless telemetry system was used to transmit the signals from the moving piston. The raw thermocouple data were processed using an inverse heat conduction method that included Tikhonov regularization to recover transient heat flux. By applying symmetry, the data were compiled to provide time-resolved spatial maps of the piston heat flux and surface temperature. A detailed comparison was made between conventional diesel combustion and reactivity-controlled compression ignition combustion operations at matched conditions of load, speed, boost pressure, and combustion phasing. The integrated piston heat transfer was found to be 24% lower, and the mean surface temperature was 25 C lower for reactivity-controlled compression ignition operation as compared to conventional diesel combustion, in spite of the higher peak heat release rate. Lower integrated piston heat transfer for reactivity-controlled compression ignition was found over all the operating conditions tested. The results showed that increasing speed decreased the integrated heat transfer for conventional diesel combustion and reactivity-controlled compression ignition. The effect of the start of injection timing was found to strongly influence conventional diesel combustion heat flux, but had a negligible effect on reactivity-controlled compression ignition heat flux, even in the limit of near top dead center high-reactivity fuel injection timings. These results suggest that the role of the high-reactivity fuel injection does not significantly affect the thermal environment even though it is important for controlling the ignition timing and heat release rate shape. The integrated heat transfer and the dynamic surface heat flux were found to be insensitive to changes in boost pressure for both conventional diesel combustion and reactivity-controlled compression ignition. However, for reactivity-controlled compression ignition, the mean surface temperature increased with changes in boost suggesting that equivalence ratio affects steady-state heat transfer.

  7. Padding with Compressed Air

    E-Print Network [OSTI]

    Beals, C.

    2004-01-01T23:59:59.000Z

    We commonly find plants using padding to transport liquids or light solids short distances from tankers into storage tanks. Padding can wreck havoc in compressed air systems with limited storage, undersized cleanup equipment (dryers and filters...

  8. Variable valve timing in a homogenous charge compression ignition engine

    DOE Patents [OSTI]

    Lawrence, Keith E.; Faletti, James J.; Funke, Steven J.; Maloney, Ronald P.

    2004-08-03T23:59:59.000Z

    The present invention relates generally to the field of homogenous charge compression ignition engines, in which fuel is injected when the cylinder piston is relatively close to the bottom dead center position for its compression stroke. The fuel mixes with air in the cylinder during the compression stroke to create a relatively lean homogeneous mixture that preferably ignites when the piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. The present invention utilizes internal exhaust gas recirculation and/or compression ratio control to control the timing of ignition events and combustion duration in homogeneous charge compression ignition engines. Thus, at least one electro-hydraulic assist actuator is provided that is capable of mechanically engaging at least one cam actuated intake and/or exhaust valve.

  9. Seismic pore space compressibility and Gassmann`s relation

    SciTech Connect (OSTI)

    Mavko, G.; Mukerji, T. [Stanford Univ., CA (United States). Rock Physics Lab.] [Stanford Univ., CA (United States). Rock Physics Lab.

    1995-11-01T23:59:59.000Z

    The pore space compressibility of a rock provides a robust, model-independent descriptor of porosity and pore fluid effects on effective moduli. The pore space compressibility is also the direct physical link between the dry and fluid-saturated moduli, and is therefore the basis of Gassmann`s equation for fluid substitution. For a fixed porosity, an increase in pore space compressibility increase the sensitivity of the modulus to fluid substitution. Two simple techniques, based on pore compressibility, are presented for graphically applying Gassmann`s relation for fluid substitution. In the first method, the pore compressibility is simply reweighted with a factor that depends only on the ratio of fluid to mineral bulk modulus. In the second technique, the rock moduli are rescaled using the Reuss average, which again depends only on the fluid and mineral moduli.

  10. Physics Basis for High-Beta, Low-Aspect-Ratio Stellarator Experiments G. H. Neilson, A. H. Reiman, M. C. Zarnstorff, A. Brooks, G.-Y. Fu, R. J. Goldston, L.-P. Ku,

    E-Print Network [OSTI]

    Physics Basis for High-Beta, Low-Aspect-Ratio Stellarator Experiments G. H. Neilson, A. H. Reiman, C. Nuehrenberg Max-Planck-Institute for Plasma Physics, D-17491 Greifswald, Germany High-beta, low and are insensitive to changes in beta. Coil configurations have been calculated that reconstruct these plasma

  11. Fuel-Free Compressed-Air Energy Storage: Fuel-Free, Ubiquitous Compressed-Air Energy Storage and Power Conditioning

    SciTech Connect (OSTI)

    None

    2010-09-13T23:59:59.000Z

    GRIDS Project: General Compression has developed a transformative, near-isothermal compressed air energy storage system (GCAES) that prevents air from heating up during compression and cooling down during expansion. When integrated with renewable generation, such as a wind farm, intermittent energy can be stored in compressed air in salt caverns or pressurized tanks. When electricity is needed, the process is reversed and the compressed air is expanded to produce electricity. Unlike conventional compressed air energy storage (CAES) projects, no gas is burned to convert the stored high-pressure air back into electricity. The result of this breakthrough is an ultra-efficient, fully shapeable, 100% renewable and carbon-free power product. The GCAES™ system can provide high quality electricity and ancillary services by effectively integrating renewables onto the grid at a cost that is competitive with gas, coal and nuclear generation.

  12. Lossy compression of weak lensing data

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

    Vanderveld, R Ali [Chicago U., EFI; Caltech /Caltech, JPL; Bernstein, Gary M [Pennsylvania U.; Stoughton, Chris [Fermilab; Rhodes, Jason [Caltech; Caltech, JPL; Massey, Richard [Royal Observ., Edinburgh; Dobke, Benjamin M [Caltech; Caltech, JPL

    2011-06-01T23:59:59.000Z

    Future orbiting observatories will survey large areas of sky in order to constrain the physics of dark matter and dark energy using weak gravitational lensing and other methods. Lossy compression of the resultant data will improve the cost and feasibility of transmitting the images through the space communication network. We evaluate the consequences of the lossy compression algorithm of Bernstein et al. (2010) for the high-precision measurement of weak-lensing galaxy ellipticities. This square-root algorithm compresses each pixel independently, and the information discarded is by construction less than the Poisson error from photon shot noise. For simulated space-based images (without cosmic rays) digitized to the typical 16 bits per pixel, application of the lossy compression followed by image-wise lossless compression yields images with only 2.4 bits per pixel, a factor of 6.7 compression. We demonstrate that this compression introduces no bias in the sky background. The compression introduces a small amount of additional digitization noise to the images, and we demonstrate a corresponding small increase in ellipticity measurement noise. The ellipticity measurement method is biased by the addition of noise, so the additional digitization noise is expected to induce a multiplicative bias on the galaxies measured ellipticities. After correcting for this known noise-induced bias, we find a residual multiplicative ellipticity bias of m {approx} -4 x 10{sup -4}. This bias is small when compared to the many other issues that precision weak lensing surveys must confront, and furthermore we expect it to be reduced further with better calibration of ellipticity measurement methods.

  13. Lossy compression of weak lensing data

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

    Vanderveld, R Ali; Bernstein, Gary M; Stoughton, Chris; Rhodes, Jason; Massey, Richard; Dobke, Benjamin M

    2011-06-01T23:59:59.000Z

    Future orbiting observatories will survey large areas of sky in order to constrain the physics of dark matter and dark energy using weak gravitational lensing and other methods. Lossy compression of the resultant data will improve the cost and feasibility of transmitting the images through the space communication network. We evaluate the consequences of the lossy compression algorithm of Bernstein et al. (2010) for the high-precision measurement of weak-lensing galaxy ellipticities. This square-root algorithm compresses each pixel independently, and the information discarded is by construction less than the Poisson error from photon shot noise. For simulated space-based images (without cosmicmore »rays) digitized to the typical 16 bits per pixel, application of the lossy compression followed by image-wise lossless compression yields images with only 2.4 bits per pixel, a factor of 6.7 compression. We demonstrate that this compression introduces no bias in the sky background. The compression introduces a small amount of additional digitization noise to the images, and we demonstrate a corresponding small increase in ellipticity measurement noise. The ellipticity measurement method is biased by the addition of noise, so the additional digitization noise is expected to induce a multiplicative bias on the galaxies measured ellipticities. After correcting for this known noise-induced bias, we find a residual multiplicative ellipticity bias of m {approx} -4 x 10{sup -4}. This bias is small when compared to the many other issues that precision weak lensing surveys must confront, and furthermore we expect it to be reduced further with better calibration of ellipticity measurement methods.« less

  14. Excitation in low-current discharges and breakdown in He at low pressures and very high electric field to gas density ratios E/N

    SciTech Connect (OSTI)

    Jelenkovic, B.M.; Phelps, A.V. [JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440 (United States); Institute of Physics, P.O. Box 75, Belgrade (Serbia and Montenegro); JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440 (United States)

    2005-01-01T23:59:59.000Z

    We investigate optical emission from low-current discharges in He at very high electric field to gas density ratios E/N between parallel plate electrodes. We also determine the electrical breakdown and the voltage-current behavior at low currents. The E/N are 300 Td to 9 kTd (1 Td=10{sup -21} V m{sup 2}) at pressures times electrode separations p{sub 0}d from 3 to 0.9 Torr cm. Absolute optical emission probabilities versus distance are determined for the 501.6 nm line (3 {sup 1}P{yields}2 {sup 1}S) and for the 587.6 nm line (3 {sup 3}D{yields}2 {sup 3}P) by reference to Boltzmann calculations at our lowest E/N and to published pressure dependent electron beam experiments. At E/N below 1 kTd, the emission follows the exponential growth of the electron density, while at above 7 kTd heavy particle excitation is evident near the cathode. Collisional transfer of excitation from the singlet to the triplet system dominates the 587.6 nm excitation. Comparisons of models with experiments show the importance of excitation and of electron production at the cathode by fast He atoms produced by charge transfer collisions of He{sup +} with He. The breakdown voltage versus p{sub 0}d is multivalued for p{sub 0}d{approx}1.5 Torr cm. At currents below 100 {mu}A and our lower E/N, the discharge voltage decreases linearly with current as expected for an increasing electron yield with ion energy and E/N at the cathode.

  15. A Compressed Air Reduction Program

    E-Print Network [OSTI]

    Hawks, K. D.

    A COMPRESSED AIR REDUCTION PROGRAM K. Dwight Hawks General Motors Corporation - Ruick-Oldsmobi1e-Cadillac Group Warren, Michigan ABSTRACT The reascn for implementing this program was to assist the plant in Quantifying some of its leaks... in the equipme~t throuqhout the plant and to provide direction as to which leaks are yenerat~ng high uti 1ity costs. The direction is very beneficial in lIlaking maintenance aware of prolill,Pls within equipment .IS \\Iell as notifying them as to whf're thei...

  16. High-precision determination of {sup 234}U/{sup 238}U activity ratios in natural waters and carbonates by ICPMS

    SciTech Connect (OSTI)

    Ketterer, M.E. [John Carroll Univ., University Heights, OH (United States). Dept. of Chemistry; Khourey, C.J. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Geological Sciences

    1998-12-31T23:59:59.000Z

    A method has been developed for precise measurement of {sup 234}U/{sup 238}U activity ratios in natural waters and carbonates using quadrupole inductively coupled plasma mass spectrometry. A recovery of 80--85% of seawater U is achieved by Fe(III) coprecipitation followed by extraction chromatography with a supported dipentyl pentane phosphonate material; 90--95% of U is recovered from carbonates, which are dissolved in HNO{sub 3} and subjected to the same extraction chromatographic preparation. Isotopic measurements are made via recirculating pneumatic nebulization of small volumes of solutions containing 0.5--5 mg/L U. {sup 234}U/{sup 235}U is measured as a proxy for determination of {sup 234}U/{sup 238}U; iridium is added to sample solutions and the ion ratio {sup 191}Ir{sup 40}Ar{sup +}/{sup 193}Ir{sup 40}Ar{sup +} is measured for internal mass discrimination correction {sup 234}U/{sup 238}U activity ratios in the range 1.143--1.154 are observed for 13 seawater and contemporary corals, in agreement with the established marine {sup 234}U/{sup 238}U activity ratio. For samples sizes of 5--25 {micro}g U, ICPMS uncertainties of {+-} 0.2--0.5% relative, 2{theta} standard error, approach those obtained for < 0.1 {micro}g U by thermal ionization mass spectrometry. Measurements of {sup 234}U/{sup 238}U activity ratios in bottled waters, Lake Erie surface waters, mollusk fossils, and fertilizers are also demonstrated.

  17. Radiative Decay of Bubble Oscillations in a Compressible Fluid

    E-Print Network [OSTI]

    A. M. Shapiro; M. I. Weinstein

    2011-01-01T23:59:59.000Z

    Consider the dynamics of a gas bubble in an inviscid, compressible liquid with surface tension. Kinematic and dynamic boundary conditions couple the bubble surface deformation dynamics with the dynamics of waves in the fluid. This system has a spherical equilibrium state, resulting from the balance of the pressure at infinity and the gas pressure within the bubble. We study the linearized dynamics about this equilibrium state in a center of mass frame: 1) We prove that the velocity potential and bubble surface perturbation satisfy point-wise in space exponential time-decay estimates. 2) The time-decay rate is governed by scattering resonances, eigenvalues of a non-selfadjoint spectral problem. These are pole singularities in the lower half plane of the analytic continuation of a resolvent operator from the upper half plane, across the real axis into the lower half plane. 3) The time-decay estimates are a consequence of resonance mode expansions for the velocity potential and bubble surface perturbations. 4) For small compressibility (Mach number, a ratio of bubble wall velocity to sound speed, \\epsilon), this is a singular perturbation of the incompressible limit. The scattering resonances which govern the anomalously slow time-decay, are {\\it Rayleigh resonances}. Asymptotics, supported by high-precision numerical studies, indicate that the Rayleigh resonances which are closest to the real axis satisfy | \\frac{\\Im \\lambda_\\star(\\epsilon)}{\\Re \\lambda_\\star(\\epsilon)} | = {\\cal O} (\\exp(-\\kappa\\ \\We\\ \\epsilon^{-2})), \\kappa>0. Here, \\We denotes the Weber number, a dimensionless ratio comparing inertia and surface tension. 5) To obtain the above results we prove a general result, of independent interest, estimating the Neumann to Dirichlet map for the wave equation, exterior to a sphere.

  18. Compressive Rendering of Multidimensional Scenes

    E-Print Network [OSTI]

    Sen, Pradeep

    Compressive Rendering of Multidimensional Scenes Pradeep Sen, Soheil Darabi, and Lei Xiao Advanced of using compressed sensing to reconstruct the 2D images produced by a rendering system, a process we called compressive rendering. In this work, we present the natural extension of this idea

  19. Blowing Ratio Effects on Film Cooling Effectiveness 

    E-Print Network [OSTI]

    Liu, Kuo-Chun

    2010-01-14T23:59:59.000Z

    . Compressed air store in the tanks entered a high flow pneumatic control valve that was designed to receive feedback from the downstream pressure to mainstream a velocity within ?3% of the desired value. The inlet and exit transition dusts of the test section...

  20. High accuracy determination of the $^{238}$U/$^{235}$U fission cross section ratio up to $\\sim$1 GeV at n_TOF (CERN)

    E-Print Network [OSTI]

    C. Paradela; M. Calviani; D. Tarr\\'\\io; E. Leal-Cidoncha; L. S. Leong; L. Tassan-Got; C. Le Naour; I. Duran; N. Colonna; L. Audouin; M. Mastromarco; S. Lo Meo; A. Ventura; S. Altstadt; J. Andrzejewski; M. Barbagallo; V. Bécares; F. Be?vá?; F. Belloni; E. Berthoumieux; J. Billowes; V. Boccone; D. Bosnar; M. Brugger; F. Calviño; D. Cano-Ott; C. Carrapiço; F. Cerutti; E. Chiaveri; M. Chin; G. Cortés; M. A. Cortés-Giraldo; L. Cosentino; M. Diakaki; C. Domingo-Pardo; R. Dressler; C. Eleftheriadis; A. Ferrari; P. Finocchiaro; K. Fraval; S. Ganesan; A. R. García; G. Giubrone; M. B. Gómez-Hornillos; I. F. Gonçalves; E. González-Romero; E. Griesmayer; C. Guerrero; F. Gunsing; P. Gurusamy; S. Heinitz; D. G. Jenkins; E. Jericha; F. Käppeler; D. Karadimos; N. Kivel; M. Kokkoris; M. Krti?ka; J. Kroll; C. Langer; C. Lederer; H. Leeb; R. Losito; A. Manousos; J. Marganiec; T. Martínez; C. Massimi; P. Mastinu; E. Mendoza; A. Mengoni; P. M. Milazzo; F. Mingrone; M. Mirea; W. Mondalaers; A. Musumarra; A. Pavlik; J. Perkowski; A. Plompen; J. Praena; J. Quesada; T. Rauscher; R. Reifarth; A. Riego; F. Roman; C. Rubbia; R. Sarmento; A. Saxena; P. Schillebeeckx; S. Schmidt; D. Schumann; G. Tagliente; J. L. Tain; A. Tsinganis; S. Valenta; G. Vannini; V. Variale; P. Vaz; R. Versaci; M. J. Vermeulen; V. Vlachoudis; R. Vlastou; A. Wallner; T. Ware; M. Weigand; C. Weiß; T. Wright; P. Žugec

    2014-10-29T23:59:59.000Z

    The $^{238}$U to $^{235}$U fission cross section ratio has been determined at n_TOF up to $\\sim$1 GeV, with two different detection systems, in different geometrical configurations. A total of four datasets have been collected and compared. They are all consistent to each other within the relative systematic uncertainty of 3-4%. The data collected at n_TOF have been suitably combined to yield a unique fission cross section ratio as a function of the neutron energy. The result confirms current evaluations up to 200 MeV. A good agreement is also observed with theoretical calculations based on the INCL++/Gemini++ combination up to the highest measured energy. The n_TOF results may help solving a long-standing discrepancy between the two most important experimental dataset available so far above 20 MeV, while extending the neutron energy range for the first time up to $\\sim$1 GeV.

  1. Efficiency Considerations of Diesel Premixed Charge Compression...

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

    Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Poster...

  2. Hydrogen Compression, Storage, and Dispensing Cost Reduction...

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

    Compression, Storage, and Dispensing Cost Reduction Workshop Addendum Hydrogen Compression, Storage, and Dispensing Cost Reduction Workshop Addendum Document states additional...

  3. CALIBRATING MS-SSIM FOR COMPRESSION DISTORTIONS USING MLDS C. Charrier1

    E-Print Network [OSTI]

    Maloney, Laurence T.

    its performance. Index Terms-- Difference scaling, Genetic algorithm, MS-SSIM. 1. INTRODUCTION Lossy image compression techniques such as JPEG2000 al- low high compression rates, but only at the cost as the compression rate is increased to optimize the construction of psychovisual scale. Such a scale will serve

  4. Compression Aware Physical Database Design

    E-Print Network [OSTI]

    Kimura, Hideaki; Syamala, Manoj

    2011-01-01T23:59:59.000Z

    Modern RDBMSs support the ability to compress data using methods such as null suppression and dictionary encoding. Data compression offers the promise of significantly reducing storage requirements and improving I/O performance for decision support queries. However, compression can also slow down update and query performance due to the CPU costs of compression and decompression. In this paper, we study how data compression affects choice of appropriate physical database design, such as indexes, for a given workload. We observe that approaches that decouple the decision of whether or not to choose an index from whether or not to compress the index can result in poor solutions. Thus, we focus on the novel problem of integrating compression into physical database design in a scalable manner. We have implemented our techniques by modifying Microsoft SQL Server and the Database Engine Tuning Advisor (DTA) physical design tool. Our techniques are general and are potentially applicable to DBMSs that support other co...

  5. Performance Analysis between Two Sparsity Constrained MRI Methods: Highly Constrained Backprojection(HYPR) and Compressed Sensing(CS) for Dynamic Imaging 

    E-Print Network [OSTI]

    Arzouni, Nibal

    2012-10-19T23:59:59.000Z

    One of the most important challenges in dynamic magnetic resonance imaging (MRI) is to achieve high spatial and temporal resolution when it is limited by system performance. It is desirable to acquire data fast enough to capture the dynamics...

  6. Making Compressed Air System Decisions

    E-Print Network [OSTI]

    Porri, R. E.

    . The design of a compressed air system was formerly limited to the selection of an air compressor large enough to deliver sufficient compressed air for the estimated system requirements. As system air requirements grew, additional compressors were added... specification, selection and installation process will follow. BACKGROUND For more than 100 years compressed air has been used throughout industry as a safe and reliable utility. The generation of this utility is performed by an air compressor. The first...

  7. New Regenerative Cycle for Vapor Compression Refrigeration

    SciTech Connect (OSTI)

    Mark J. Bergander

    2005-08-29T23:59:59.000Z

    The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

  8. Measurements of carbon monoxide mixing ratios in Houston using a compact high-power CW DFB-QCL-based QEPAS sensor

    E-Print Network [OSTI]

    and water heaters, stoves and other gasoline pow- ered equipment used in households. Typically, CO levels of 0.5­5 ppm are expected in homes in the absence of high-efficiency heaters and stoves. In spaces where gas stoves/heaters are operated, the CO concentration can increase up to 30 ppm [6]. In this work

  9. Compression of solid nitromethane to 15 GPa at 298 K

    SciTech Connect (OSTI)

    Yarger, F.L.; Olinger, B.

    1986-08-01T23:59:59.000Z

    The measurement of the isothermal compression of solid nitromethane to 15 GPa at 298 K using high pressure x-ray diffraction techniques is described. The compression data are fit to a model from which bulk moduli are calculated. Most interesting are the linear compression data. The a axis direction, along which the C--N bonds are aligned, shows little increase in repulsion with increasing pressure above 5 GPa. This indicates that the nitro and methyl groups of neighboring molecules may be interacting.

  10. An Efficient, Semi-implicit Pressure-based Scheme Employing a High-resolution Finitie Element Method for Simulating Transient and Steady, Inviscid and Viscous, Compressible Flows on Unstructured Grids

    SciTech Connect (OSTI)

    Richard C. Martineau; Ray A. Berry

    2003-04-01T23:59:59.000Z

    A new semi-implicit pressure-based Computational Fluid Dynamics (CFD) scheme for simulating a wide range of transient and steady, inviscid and viscous compressible flow on unstructured finite elements is presented here. This new CFD scheme, termed the PCICEFEM (Pressure-Corrected ICE-Finite Element Method) scheme, is composed of three computational phases, an explicit predictor, an elliptic pressure Poisson solution, and a semiimplicit pressure-correction of the flow variables. The PCICE-FEM scheme is capable of second-order temporal accuracy by incorporating a combination of a time-weighted form of the two-step Taylor-Galerkin Finite Element Method scheme as an explicit predictor for the balance of momentum equations and the finite element form of a time-weighted trapezoid rule method for the semi-implicit form of the governing hydrodynamic equations. Second-order spatial accuracy is accomplished by linear unstructured finite element discretization. The PCICE-FEM scheme employs Flux-Corrected Transport as a high-resolution filter for shock capturing. The scheme is capable of simulating flows from the nearly incompressible to the high supersonic flow regimes. The PCICE-FEM scheme represents an advancement in mass-momentum coupled, pressurebased schemes. The governing hydrodynamic equations for this scheme are the conservative form of the balance of momentum equations (Navier-Stokes), mass conservation equation, and total energy equation. An operator splitting process is performed along explicit and implicit operators of the semi-implicit governing equations to render the PCICE-FEM scheme in the class of predictor-corrector schemes. The complete set of semi-implicit governing equations in the PCICE-FEM scheme are cast in this form, an explicit predictor phase and a semi-implicit pressure-correction phase with the elliptic pressure Poisson solution coupling the predictor-corrector phases. The result of this predictor-corrector formulation is that the pressure Poisson equation in the PCICE-FEM scheme is provided with sufficient internal energy information to avoid iteration. The ability of the PCICE-FEM scheme to accurately and efficiently simulate a wide variety of inviscid and viscous compressible flows is demonstrated here.

  11. PHELIX for flux compression studies

    SciTech Connect (OSTI)

    Turchi, Peter J [Los Alamos National Laboratory; Rousculp, Christopher L [Los Alamos National Laboratory; Reinovsky, Robert E [Los Alamos National Laboratory; Reass, William A [Los Alamos National Laboratory; Griego, Jeffrey R [Los Alamos National Laboratory; Oro, David M [Los Alamos National Laboratory; Merrill, Frank E [Los Alamos National Laboratory

    2010-06-28T23:59:59.000Z

    PHELIX (Precision High Energy-density Liner Implosion eXperiment) is a concept for studying electromagnetic implosions using proton radiography. This approach requires a portable pulsed power and liner implosion apparatus that can be operated in conjunction with an 800 MeV proton beam at the Los Alamos Neutron Science Center. The high resolution (< 100 micron) provided by proton radiography combined with similar precision of liner implosions driven electromagnetically can permit close comparisons of multi-frame experimental data and numerical simulations within a single dynamic event. To achieve a portable implosion system for use at high energy-density in a proton laboratory area requires sub-megajoule energies applied to implosions only a few cms in radial and axial dimension. The associated inductance changes are therefore relatively modest, so a current step-up transformer arrangement is employed to avoid excessive loss to parasitic inductances that are relatively large for low-energy banks comprising only several capacitors and switches. We describe the design, construction and operation of the PHELIX system and discuss application to liner-driven, magnetic flux compression experiments. For the latter, the ability of strong magnetic fields to deflect the proton beam may offer a novel technique for measurement of field distributions near perturbed surfaces.

  12. Streaming Compression of Hexahedral Meshes

    SciTech Connect (OSTI)

    Isenburg, M; Courbet, C

    2010-02-03T23:59:59.000Z

    We describe a method for streaming compression of hexahedral meshes. Given an interleaved stream of vertices and hexahedral our coder incrementally compresses the mesh in the presented order. Our coder is extremely memory efficient when the input stream documents when vertices are referenced for the last time (i.e. when it contains topological finalization tags). Our coder then continuously releases and reuses data structures that no longer contribute to compressing the remainder of the stream. This means in practice that our coder has only a small fraction of the whole mesh in memory at any time. We can therefore compress very large meshes - even meshes that do not file in memory. Compared to traditional, non-streaming approaches that load the entire mesh and globally reorder it during compression, our algorithm trades a less compact compressed representation for significant gains in speed, memory, and I/O efficiency. For example, on the 456k hexahedra 'blade' mesh, our coder is twice as fast and uses 88 times less memory (only 3.1 MB) with the compressed file increasing about 3% in size. We also present the first scheme for predictive compression of properties associated with hexahedral cells.

  13. Data Compression with Prime Numbers

    E-Print Network [OSTI]

    Gordon Chalmers

    2005-11-16T23:59:59.000Z

    A compression algorithm is presented that uses the set of prime numbers. Sequences of numbers are correlated with the prime numbers, and labeled with the integers. The algorithm can be iterated on data sets, generating factors of doubles on the compression.

  14. Shock compression profiles in ceramics

    SciTech Connect (OSTI)

    Grady, D.E.; Moody, R.L.

    1996-03-01T23:59:59.000Z

    An investigation of the shock compression properties of high-strength ceramics has been performed using controlled planar impact techniques. In a typical experimental configuration, a ceramic target disc is held stationary, and it is struck by plates of either a similar ceramic or by plates of a well-characterized metal. All tests were performed using either a single-stage propellant gun or a two-stage light-gas gun. Particle velocity histories were measured with laser velocity interferometry (VISAR) at the interface between the back of the target ceramic and a calibrated VISAR window material. Peak impact stresses achieved in these experiments range from about 3 to 70 GPa. Ceramics tested under shock impact loading include: Al{sub 2}O{sub 3}, AlN, B{sub 4}C, SiC, Si{sub 3}N{sub 4}, TiB{sub 2}, WC and ZrO{sub 2}. This report compiles the VISAR wave profiles and experimental impact parameters within a database-useful for response model development, computational model validation studies, and independent assessment of the physics of dynamic deformation on high-strength, brittle solids.

  15. Efficient Joins with Compressed Bitmap Indexes

    E-Print Network [OSTI]

    Madduri, Kamesh

    2010-01-01T23:59:59.000Z

    compression is extremely e?cient for compressing bitmap indexescompression: There are however various approaches to extend the e?ectiveness of bitmap indexes

  16. Premix charge, compression ignition combustion system optimization...

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

    Premix charge, compression ignition combustion system optimization Premix charge, compression ignition combustion system optimization Presentation given at DEER 2006, August 20-24,...

  17. The decommodified security ratio

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    are currently experiencing: changing patterns of work, the phenom- enon she calls the "breakdown in the wage furthered by the work of the International Labour Office. In particular, the programme of researchThe decommodified security ratio: A tool for assessing European social protection systems Georges

  18. AN ASSESSMENT OF THE BRAYTON CYCLE FOR HIGH PERFORMANCE POWER PLANTS R. Schleicher A. R. Raffray C. P. Wong

    E-Print Network [OSTI]

    Raffray, A. René

    and the risk associated with oil lubricated bearings.2 Interest in nuclear CCGTs was revived in the 1990s effectiveness and cycle fractional pressure loss. The compression ratio is also important because for fusion because due to non-competitive economics, mainly attributed to the lack of high effectiveness recuperators

  19. AN ASSESSMENT OF THE BRAYTON CYCLE FOR HIGH PERFORMANCE POWER PLANTS R. Schleicher A. R. Raffray C. P. Wong

    E-Print Network [OSTI]

    California at San Diego, University of

    and the risk associated with oil lubricated bearings. 2 Interest in nuclear CCGTs was revived in the 1990s effectiveness and cycle fractional pressure loss. The compression ratio is also important because for fusion because due to non-competitive economics, mainly attributed to the lack of high effectiveness recuperators

  20. Dynamic control of a homogeneous charge compression ignition engine

    DOE Patents [OSTI]

    Duffy, Kevin P. (Metamora, IL); Mehresh, Parag (Peoria, IL); Schuh, David (Peoria, IL); Kieser, Andrew J. (Morton, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL)

    2008-06-03T23:59:59.000Z

    A homogenous charge compression ignition engine is operated by compressing a charge mixture of air, exhaust and fuel in a combustion chamber to an autoignition condition of the fuel. The engine may facilitate a transition from a first combination of speed and load to a second combination of speed and load by changing the charge mixture and compression ratio. This may be accomplished in a consecutive engine cycle by adjusting both a fuel injector control signal and a variable valve control signal away from a nominal variable valve control signal. Thereafter in one or more subsequent engine cycles, more sluggish adjustments are made to at least one of a geometric compression ratio control signal and an exhaust gas recirculation control signal to allow the variable valve control signal to be readjusted back toward its nominal variable valve control signal setting. By readjusting the variable valve control signal back toward its nominal setting, the engine will be ready for another transition to a new combination of engine speed and load.

  1. Compressibility of Nuclear Matter from Shell Effects in Nuclei

    E-Print Network [OSTI]

    M. M. Sharma

    1999-04-13T23:59:59.000Z

    The compressibility of nuclear matter has received significant attention in the last decade and a variety of approaches have been employed to extract this fundamental property of matter. Recently, significant differences have emerged between the results of relativistic and non-relativistic calculations of breathing mode giant monopole resonance (GMR). This is due to a lack of understanding of the dynamics of GMR and of its exact relationship to the compression modulus of the infinite nuclear matter. Here, I present an alternative approach based upon nuclear shell effects. The shell effects are known to manifest experimentally in terms of particle-separation energies with an exceedingly high precision. Within the framework of the non-relativistic density-dependent Skyrme theory, it is shown that the compressibility of nuclear matter has a significant influence on shell effects in nuclei. It is shown that 2-neutron separation energies and hence the empirical shell effects can be used to constrain the compressibility of nuclear matter.

  2. Multi-ratio transmission

    SciTech Connect (OSTI)

    Polak, J.C.

    1987-07-14T23:59:59.000Z

    A preselected multi-ratio power transmission is described comprising: input means for transmitting drive forces; output means; first, second and third friction clutch means each selectively engageable with the input means for accepting drive forces. First input gear means drivingly connects with the first friction clutch means; second input gear means drivingly connects with the second friction clutch means; third input gear means drivingly connects with the third clutch means; first output gear means drivingly connects with the first input gear means; second output gear means drivingly connects with the first and second input gear means; third output means drivingly connects between the third input gear means and the output means; and one double-acting synchronizer clutch for selectively engaging the first output gear means with the output means and alternately the second output gear means with the output means. The first friction clutch means and the one double-acting synchronizer clutch cooperates during engagement to establish two forward drive ratios between the input and output means. The second friction clutch means and the one double-acting synchronizer clutch cooperates during engagement to establish two other forward drive ratios between the input and output means. The third friction clutch means is engageable to provide another forward drive ratio between the input means and the output means; and the one double-acting synchronizer clutch is relieved of transmitting drive forces during the engagement of the third friction clutch means and being manipulable for alternate connection with either the first output gear or the second output gear while the third friction clutch means is engaged.

  3. Compressed Air Audits using AIRMaster

    E-Print Network [OSTI]

    Wheeler, G. M.; McGill, R. D.; Bessey, E. G.; Vischer, K.

    Air compressors are a significant industrial energy user and therefore a prime target for industrial energy audits. The project goal was to develop a software tool, AIRMaster, and supporting methodology for performing compressed air system audits...

  4. Evaluation of compression members with non-ideal end conditions

    E-Print Network [OSTI]

    Marek, David Leslie

    1993-01-01T23:59:59.000Z

    f/ cr effective connection restraint (k-in/rad), modulus of elasticity (ksi), yield stress of steel (ksi), ratio of stiffness (non-dimensional), moment of inertia about axis of buckling (in4), effective length factor (non-dimensional), length... of compression member (in), plastic moment capacity of the column (k-in), critical buckling load (kips) rotational stiffness of connection (k-in/rad), end restraint parameter (non-dimensional), buckling load parameter (non-dimensional), approximate function...

  5. Lithium, compression and high-pressure structure

    SciTech Connect (OSTI)

    Olinger, B.; Shaner, J.W.

    1983-03-04T23:59:59.000Z

    Lithium is found to transform from a body-centered cubic (bcc) to a face-centered cubic (fcc) structure at 6.9 gigapascals (69 kilobars) and 296 kelvin. The relative volume of the bcc structured lithium at 6.9 gigapascals is 0.718, and the fcc structure is 0.25 percent denser. The bulk modulus and its pressure derivative for the bcc structure are 11.57 gigapascals and 3.4, and for the fcc structure are 13.1 gigapascals and 2.8. Extrapolation of the bcc-fcc phase boundary and the melting curve indiactes a triple point around 15 gigapascals and 500 kelvin.

  6. High-Performance Wavelet Compression for Mammography ...

    E-Print Network [OSTI]

    2005-11-29T23:59:59.000Z

    was compliant with the Health Insur- ance Portability and Accountability Act. .... care was taken to maintain at least an. 8-week interval between readings of the.

  7. The wavelet/scalar quantization compression standard for digital fingerprint images

    SciTech Connect (OSTI)

    Bradley, J.N.; Brislawn, C.M.

    1994-04-01T23:59:59.000Z

    A new digital image compression standard has been adopted by the US Federal Bureau of Investigation for use on digitized gray-scale fingerprint images. The algorithm is based on adaptive uniform scalar quantization of a discrete wavelet transform image decomposition and is referred to as the wavelet/scalar quantization standard. The standard produces archival quality images at compression ratios of around 20:1 and will allow the FBI to replace their current database of paper fingerprint cards with digital imagery.

  8. Vortex stabilized electron beam compressed fusion grade plasma

    SciTech Connect (OSTI)

    Hershcovitch, Ady [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-03-19T23:59:59.000Z

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  9. ARM - Measurement - Isotope ratio

    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 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSizegovMeasurementsIsotope ratio

  10. SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) 2013

    SciTech Connect (OSTI)

    Gordon Rueff; Lyle Roybal; Denis Vollmer

    2013-01-01T23:59:59.000Z

    There is a significant need to protect the nation’s energy infrastructures from malicious actors using cyber methods. Supervisory, Control, and Data Acquisition (SCADA) systems may be vulnerable due to the insufficient security implemented during the design and deployment of these control systems. This is particularly true in older legacy SCADA systems that are still commonly in use. The purpose of INL’s research on the SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) project was to determine if and how data compression techniques could be used to identify and protect SCADA systems from cyber attacks. Initially, the concept was centered on how to train a compression algorithm to recognize normal control system traffic versus hostile network traffic. Because large portions of the TCP/IP message traffic (called packets) are repetitive, the concept of using compression techniques to differentiate “non-normal” traffic was proposed. In this manner, malicious SCADA traffic could be identified at the packet level prior to completing its payload. Previous research has shown that SCADA network traffic has traits desirable for compression analysis. This work investigated three different approaches to identify malicious SCADA network traffic using compression techniques. The preliminary analyses and results presented herein are clearly able to differentiate normal from malicious network traffic at the packet level at a very high confidence level for the conditions tested. Additionally, the master dictionary approach used in this research appears to initially provide a meaningful way to categorize and compare packets within a communication channel.

  11. D.D. Luong et al. / Journal of Alloys and Compounds 550 (2013) 412422 412 Development of high performance lightweight aluminum alloy/SiC hollow sphere syntactic foams and compressive

    E-Print Network [OSTI]

    Gupta, Nikhil

    2013-01-01T23:59:59.000Z

    performance lightweight aluminum alloy/SiC hollow sphere syntactic foams and compressive characterization and Materials Research Directorate, Aberdeen Proving Ground, MD 21005 USA ABSTRACT Aluminum alloy A356 filled matrix composite (AMC) systems. Aluminum alloys and AMCs have been used to replace steel in automotive

  12. Coke cake behavior under compressive forces

    SciTech Connect (OSTI)

    Watakabe, S.; Takeda, T.; Itaya, H.; Suginobe, H.

    1997-12-31T23:59:59.000Z

    The deformation of the coke cake and load on the side wall during pushing were studied using an electric furnace equipped with a movable wall. Coke cake was found to deform in three stages under compressive forces. The coke cake was shortened in the pushing direction in the cake deformation stage, and load was generated on the side walls in the high wall load stage. Secondary cracks in the coke cake were found to prevent load transmission on the wall. The maximum load transmission rate was controlled by adjusting the maximum fluidity and mean reflectance of the blended coal.

  13. Viscosity, entropy and the viscosity to entropy density ratio; how perfect is a nucleonic fluid?

    E-Print Network [OSTI]

    Aram Z. Mekjian

    2010-09-29T23:59:59.000Z

    The viscosity of hadronic matter is studied using a classical evaluation of the scattering angle and a quantum mechanical discussion based on phase shifts from a potential. Semi classical limits of the quantum theory are presented. A hard sphere and an attractive square well potential step are each considered as well as the combined effects of both. The lowest classical value of the viscosity for an attractive potential is shown to be a hard sphere limit. The high wave number-short wavelength limits of the quantum result have scaling laws associated with it for both the viscosity and entropy. These scaling laws are similar to the Fraunhoher diffraction increase for the hard sphere geometric cross section. Specific examples for nuclear collisions are given. The importance of the nuclear tensor force and hard core is mentioned. The viscosity (eta), entropy density (s) and eta/s ratio are calculated for a gas of dilute neutrons in the unitary limit of large scattering length. Away from the unitary limit, the ratio of the interaction radius or the scattering length to the interparticle spacing introduces a variable y besides the fugacity z. The isothermal compressibility is shown to impose important constraints. The results for eta/s are compared to the AdS/CFT string theory minimum of (1/4Pi)hbar/kb to see how close a nucleonic gas is to being a perfect fluid. The eta/s ~1hbar/kb for a neutron gas in its unitary limit. The eta/s 3hbar/kb treating the nuclear scattering as billiard ball collisions. The minimum eta/s for a neutron gas occurs in regions of negative isothermal compressibility and high fugacity where higher virial terms are important. In a neutron-proton system higher virial terms are associated with a liquid-gas phase transition and critical opalescent phenomena.The type of flow-laminar,vortex, turbulent- is investigated.

  14. Cryo-Compressed Hydrogen Storage: Performance and Cost Review...

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

    Compressed Hydrogen Storage: Performance and Cost Review Cryo-Compressed Hydrogen Storage: Performance and Cost Review Presented at the R&D Strategies for Compressed,...

  15. Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System

    SciTech Connect (OSTI)

    None

    2012-01-04T23:59:59.000Z

    HEATS Project: UTRC is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant. This unique working pair can operate indefinitely as a traditional vapor compression heat pump using electrical energy, if desired. The project will deliver a hot-and-cold battery that provides comfort to the passengers using minimal power, substantially extending the driving range of EVs.

  16. Low Temperature Combustion Demonstrator for High Efficiency Clean...

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

    Turbocharging Optimum CR and VVA Compression Ratio Bottoming Cycles Rankine Cycle Turbo Compounding Base engine development Parasitic Losses Aftertreatment Management 2009...

  17. Few-cycle self-compression via multimode nonlinear optics in gas filled waveguides

    E-Print Network [OSTI]

    and spatial confinement of the pulse within the capillary, coupled with the relatively low gas pressuresFew-cycle self-compression via multimode nonlinear optics in gas filled waveguides P. N. Anderson1-compression of high energy ultrashort pulses within short gas filled capillaries. The mechanism observed allows

  18. Hydrogen Delivery Liquefaction & Compression

    E-Print Network [OSTI]

    temperature refrigeration Magnetic refrigerators Acoustic refrigerators #12;12 Challenges: More cost effective Refrigeration GN2 to N2 Liquefier To Feed H2 Flash Compressor H2 Recycle Compressor LN2 Add. To Storage/Fill #12 Higher efficiency compressors and expanders More efficient refrigeration Lower cost high

  19. Real-Time SCADA Cyber Protection Using Compression Techniques

    SciTech Connect (OSTI)

    Lyle G. Roybal; Gordon H Rueff

    2013-11-01T23:59:59.000Z

    The Department of Energy’s Office of Electricity Delivery and Energy Reliability (DOE-OE) has a critical mission to secure the energy infrastructure from cyber attack. Through DOE-OE’s Cybersecurity for Energy Delivery Systems (CEDS) program, the Idaho National Laboratory (INL) has developed a method to detect malicious traffic on Supervisory, Control, and Data Acquisition (SCADA) network using a data compression technique. SCADA network traffic is often repetitive with only minor differences between packets. Research performed at the INL showed that SCADA network traffic has traits desirable for using compression analysis to identify abnormal network traffic. An open source implementation of a Lempel-Ziv-Welch (LZW) lossless data compression algorithm was used to compress and analyze surrogate SCADA traffic. Infected SCADA traffic was found to have statistically significant differences in compression when compared against normal SCADA traffic at the packet level. The initial analyses and results are clearly able to identify malicious network traffic from normal traffic at the packet level with a very high confidence level across multiple ports and traffic streams. Statistical differentiation between infected and normal traffic level was possible using a modified data compression technique at the 99% probability level for all data analyzed. However, the conditions tested were rather limited in scope and need to be expanded into more realistic simulations of hacking events using techniques and approaches that are better representative of a real-world attack on a SCADA system. Nonetheless, the use of compression techniques to identify malicious traffic on SCADA networks in real time appears to have significant merit for infrastructure protection.

  20. Advanced Management of Compressed Air Systems

    Office of Energy Efficiency and Renewable Energy (EERE)

    Find out how a compressed air system works and the benefits of optimal compressed air system performance. This training is designed to help end users as well as industry solution providers learn...

  1. Compressed Gas EHS-2200-WEB

    E-Print Network [OSTI]

    Compressed Gas Safety EHS-2200-WEB Register and launch through http://axess.stanford.edu Course title and STARS number: General Safety & Emergency Preparedness EHS-4200-WEB Chemical Safety for Laboratories EHS-1900-WEB Biosafety EHS-1500-WEB Radiation Safety Training EHS-5250 Laser Safety EHS-4820-WEB

  2. Image Compression by Back Propagation

    E-Print Network [OSTI]

    Cottrell, Garrison W.

    CHAPTER 9 Image Compression by Back Propagation: An Example of Extensional Programming* GARRISON W the case with the computatiolls associated with basic cognitive pro- cesses such as vision and audition techniques. The technique we employ is known as back propagation. developed by l1umelhart, Hinton

  3. IEA Workshop 59 Shape and Aspect Ratio Optimization for

    E-Print Network [OSTI]

    IEA Workshop 59 Shape and Aspect Ratio Optimization for High Beta, Steady-State Tokamak SCOPE and aspect ratio is particularly important for achieving high beta and also for the optimization of edge optimization of high beta steady state tokamak including DEMO concept, stability and CD assessment

  4. Compression of cooked freeze-dried carrots

    E-Print Network [OSTI]

    Macphearson, Bruce Alan

    1973-01-01T23:59:59.000Z

    to precompression characteristics (Brockmann, 1966). Hsmdy (1962) found that acceptable, compressed and freeze-dried spinach could be obtained by plasticizing the product to a moisture content of 9X before compression. Ishler (1962) reported that spraying... the dehydrated food before compression with either water, glycerine or propylene glycol produced bars with excellent rehydra- tion characteristics. He recommended spraying freeze-dried cellu- lar foods to 5-13X moisture, compressing, and redrying to lees than...

  5. POSTER PRESENTATION Open Access Compressed sensing with stochastic spikes

    E-Print Network [OSTI]

    Kreiter, Andreas K.

    POSTER PRESENTATION Open Access Compressed sensing with stochastic spikes David Rotermund* , Klaus of a high dimensional state can be possible also from much lower dimensional sam- ples provided the state for non- negative activities can efficiently exploit the information contained in stochastic spike events

  6. DIRECT SIMULATION OF SPATIALLY EVOLVING COMPRESSIBLE TURBULENT BOUNDARY LAYERS

    E-Print Network [OSTI]

    Erlebacher, Gordon

    of the cold wall condition used in Ref. 6, and, other differences. The computational method used in this study compressible flows because of the interest in designing high speed vehicles and the associated propulsion on temperature. Under the adiabatic conditions of the experiment, the temperature increases as the wall

  7. Pulse compression in plasma: generation of femtosecond pulses without CPA

    E-Print Network [OSTI]

    ­frequency laser beam into the energy of a short lower­frequency laser pulse. The standard approach to generating high­intensity ultra­short laser pulses is Chirped Pulse Amplification [1] (CPA), in which a laser Garching, Germany Abstract: Laser pulses can be e#ciently compressed to femto­ second duration when

  8. Pellet Production Wood Pellets are made by compressing

    E-Print Network [OSTI]

    Pellet Production Wood Pellets are made by compressing clean dry sawdust, under very high pressure into a pellet as it cools. The material used for producing pellets usually comes from industries who are already pellets reduces the volume of material they have to treat as waste, reducing landfill. Pellets have

  9. Compression of redundancy free trellis stages in Turbo-Decoder

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Compression of redundancy free trellis stages in Turbo-Decoder E. Boutillon, J. Sánchez-Rojas and C. Marchand For turbo code with coding rate close to one, the high puncturing rate induces long sequences. The computation is reduced accordingly. Introduction: Turbo codes with coding rate close to one are specified

  10. Compressed Air System Analysis and Retrofit for Energy Savings 

    E-Print Network [OSTI]

    Harding, C.; Nutter, D.

    2014-01-01T23:59:59.000Z

    . Therefore, high quality compressed air is a key component of that objective. The compressed air used in the manufacturing process at this facility is held to ISO (International Organization for Standardization) class 2 air quality standards.... The compressor room contained two wet storage tanks, with a total capacity of 1,800 gallons. A heated desiccant dryer with associated filters was also located in the compressor room. Dry air was sent into the plant to a 2,000 gallon dry storage tank, which...

  11. Compressive turbulent cascade and heating in the solar wind

    SciTech Connect (OSTI)

    Marino, R. [Dipartimento di Fisica, Universita della Calabria, Ponte Bucci 31C, I-87036 Rende (Italy); University of Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, B.P. 4229, 06304 Nice Cedex 4 (France); Sorriso-Valvo, L. [Liquid Crystal Laboratory, INFM/CNR, Ponte Bucci 33B, I-87036 Rende (Italy); Carbone, V. [Dipartimento di Fisica, Universita della Calabria, Ponte Bucci 31C, I-87036 Rende (Italy); Noullez, A. [University of Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, B.P. 4229, 06304 Nice Cedex 4 (France); Bruno, R. [INAF-Istituto Fisica Spazio Interplanetario, Rome (Italy)

    2010-03-25T23:59:59.000Z

    A turbulent energy cascade has been recently identified in high-latitude solar wind data samples by using a Yaglom-like relation. However, analogous scaling law, suitably modified to take into account compressible fluctuations, has been observed in a much more extended fraction of the same data set recorded by the Ulysses spacecraft. Thus, it seems that large scale density fluctuations, despite their low amplitude, play a major role in the basic scaling properties of turbulence. The compressive turbulent cascade, moreover, seems to be able to supply the energy needed to account for the local heating of the non-adiabatic solar wind.

  12. International magnetic pulse compression workshop: (Proceedings)

    SciTech Connect (OSTI)

    Kirbie, H.C.; Newton, M.A.; Siemens, P.D.

    1991-04-01T23:59:59.000Z

    A few individuals have tried to broaden the understanding of specific and salient pulsed-power topics. One such attempt is this documentation of a workshop on magnetic switching as it applies primarily to pulse compression (power transformation), affording a truly international perspective by its participants under the initiative and leadership of Hugh Kirbie and Mark Newton of the Lawrence Livermore National Laboratory (LLNL) and supported by other interested organizations. During the course of the Workshop at Granlibakken, a great deal of information was amassed and a keen insight into both the problems and opportunities as to the use of this switching approach was developed. The segmented workshop format proved ideal for identifying key aspects affecting optimum performance in a variety of applications. Individual groups of experts addressed network and system modeling, magnetic materials, power conditioning, core cooling and dielectrics, and finally circuits and application. At the end, they came together to consolidate their input and formulate the workshop's conclusions, identifying roadblocks or suggesting research projects, particularly as they apply to magnetic switching's trump card--its high-average-power-handling capability (at least on a burst-mode basis). The workshop was especially productive both in the quality and quantity of information transfer in an environment conducive to a free and open exchange of ideas. We will not delve into the organization proper of this meeting, rather we wish to commend to the interested reader this volume, which provides the definitive and most up-to-date compilation on the subject of magnetic pulse compression from underlying principles to current state of the art as well as the prognosis for the future of magnetic pulse compression as a consensus of the workshop's organizers and participants.

  13. Compressibility and strength of nanocrystalline tungsten boride under compression to 60GPa

    E-Print Network [OSTI]

    Duffy, Thomas S.

    Compressibility and strength of nanocrystalline tungsten boride under compression to 60GPa Haini://jap.aip.org/about/rights_and_permissions #12;Compressibility and strength of nanocrystalline tungsten boride under compression to 60 GPa Haini of nanocrystalline tungsten boride (WB) were investigated using radial x-ray diffraction (RXRD) in a diamond

  14. Isentropic compression studies using the NHMFL single turn

    SciTech Connect (OSTI)

    Tasker, Douglas G [Los Alamos National Laboratory; Mielke, Charles [Los Alamos National Laboratory; Rodriguez, George [Los Alamos National Laboratory; Rickel, Dwight [Los Alamos National Laboratory

    2010-10-19T23:59:59.000Z

    Magnetic isentropic compression experiments (ICE) provide the most accurate shock free compression data for materials at megabar stresses. Recent ICE experiments performed on the Sandia Z-machine (Asay, 1999) and at the Los Alamos High Explosive Pulsed Power facility (Tasker, 2006) are providing our nation with data on material properties in extreme dynamic high stress environments. The LANL National High Magnetic Field Laboratory (NHMFL) can offer a less complex ICE experiment at high stresses (up to {approx}1Mbar) with a high sample throughput and relatively low cost. This is not to say that the NHMFL technique will replace the other methods but rather complement them. For example, NHMFL-ICE is ideal for the development of advanced diagnostics, e.g., to detect phase changes. We will discuss the physics of the NHMFL-ICE experiments and present data from the first proof-of-principle experiments that were performed in September 2010.

  15. IN SITU ELLIPSOMETRY FOR SHOCK COMPRESSION MEASUREMENTS

    SciTech Connect (OSTI)

    Bakshi, L. [Mechanical Engineering Department, Ben Gurion University, Beer Sheva 84105 (Israel); Soreq NRC, Yavne 81800 (Israel); Eliezer, S.; Appelbaum, G.; Nissim, N.; Perelmutter, L. [Soreq NRC, Yavne 81800 (Israel); Mond, M. [Mechanical Engineering Department, Ben Gurion University, Beer Sheva 84105 (Israel)

    2009-12-28T23:59:59.000Z

    Knowledge about the optical properties of materials at high pressure and high temperature is needed for EOS research. Ellipsometry measures the change in the polarization of a probe beam reflected from a surface. From the change in polarization, the real and imaginary parts of the time dependent complex index of refraction can be extracted. From the measured optical properties, fundamental physical properties of the material, such as emissivity, phase transitions, and electrical conductivity can be extracted. A dynamic ellipsometry measurement system with nanosecond resolution was built in order to measure all four stocks parameters. Gas gun was used to accelerate the impact flyer. Our experiments concentrated on the optical properties of 1020 steel targets with impact pressure range of 40-250 kbar. Although there are intrinsic difficulties with dynamic ellipsometric measurements, distinct changes were observed for 1020 steel under shock compression larger than 130 kbar, the alpha->epsilon phase transition.

  16. Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II), a novel pulse-compressing ion accelerator

    SciTech Connect (OSTI)

    Friedman, A; Barnard, J J; Cohen, R H; Grote, D P; Lund, S M; Sharp, W M; Faltens, A; Henestroza, E; Jung, J; Kwan, J W; Lee, E P; Leitner, M A; Logan, B G; Vay, J; Waldron, W L; Davidson, R C; Dorf, M; Gilson, E P; Kaganovich, I

    2009-11-19T23:59:59.000Z

    Intense beams of heavy ions are well suited for heating matter to regimes of emerging interest. A new facility, NDCX-II, will enable studies of warm dense matter at {approx}1 eV and near-solid density, and of heavy-ion inertial fusion target physics relevant to electric power production. For these applications the beam must deposit its energy rapidly, before the target can expand significantly. To form such pulses, ion beams are temporally compressed in neutralizing plasma; current amplification factors of {approx}50-100 are routinely obtained on the Neutralized Drift Compression Experiment (NDCX) at LBNL. In the NDCX-II physics design, an initial non-neutralized compression renders the pulse short enough that existing high-voltage pulsed power can be employed. This compression is first halted and then reversed by the beam's longitudinal space-charge field. Downstream induction cells provide acceleration and impose the head-to-tail velocity gradient that leads to the final neutralized compression onto the target. This paper describes the discrete-particle simulation models (1-D, 2-D, and 3-D) employed and the space-charge-dominated beam dynamics being realized.

  17. Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II),a novel pulse-compressing ion accelerator

    SciTech Connect (OSTI)

    Friedman, A.; Barnard, J.J.; Cohen, R.H.; Grote, D.P.; Lund, S.M.; Sharp, W.M.; Faltens, A.; Henestroza, E.; Jung, J.-Y.; Kwan, J.W.; Lee, E.P.; Leitner, M.A.; Logan, B.G.; Vay, J.-L.; Waldron, W.L.; Davidson, R.C.; Dorf, M.; Gilson, E.P.; Kaganovich, I.D.

    2009-12-19T23:59:59.000Z

    Intense beams of heavy ions are well suited for heating matter to regimes of emerging interest. A new facility, NDCX-II, will enable studies of warm dense matter at {approx}1 eV and near-solid density, and of heavy-ion inertial fusion target physics relevant to electric power production. For these applications the beam must deposit its energy rapidly, before the target can expand significantly. To form such pulses, ion beams are temporally compressed in neutralizing plasma; current amplification factors of {approx}50-100 are routinely obtained on the Neutralized Drift Compression Experiment (NDCX) at LBNL. In the NDCX-II physics design, an initial non-neutralized compression renders the pulse short enough that existing high-voltage pulsed power can be employed. This compression is first halted and then reversed by the beam's longitudinal space-charge field. Downstream induction cells provide acceleration and impose the head-to-tail velocity gradient that leads to the final neutralized compression onto the target. This paper describes the discrete-particle simulation models (1-D, 2-D, and 3-D) employed and the space-charge-dominated beam dynamics being realized.

  18. Frequency extrapolation by nonconvex compressive sensing

    SciTech Connect (OSTI)

    Chartrand, Rick [Los Alamos National Laboratory; Sidky, Emil Y [UNIV OF CHICAGO; Pan, Xiaochaun [UNIV OF CHICAGO

    2010-12-03T23:59:59.000Z

    Tomographic imaging modalities sample subjects with a discrete, finite set of measurements, while the underlying object function is continuous. Because of this, inversion of the imaging model, even under ideal conditions, necessarily entails approximation. The error incurred by this approximation can be important when there is rapid variation in the object function or when the objects of interest are small. In this work, we investigate this issue with the Fourier transform (FT), which can be taken as the imaging model for magnetic resonance imaging (MRl) or some forms of wave imaging. Compressive sensing has been successful for inverting this data model when only a sparse set of samples are available. We apply the compressive sensing principle to a somewhat related problem of frequency extrapolation, where the object function is represented by a super-resolution grid with many more pixels than FT measurements. The image on the super-resolution grid is obtained through nonconvex minimization. The method fully utilizes the available FT samples, while controlling aliasing and ringing. The algorithm is demonstrated with continuous FT samples of the Shepp-Logan phantom with additional small, high-contrast objects.

  19. Liquid piston gas compression James D. Van de Ven a,*, Perry Y. Li b,1

    E-Print Network [OSTI]

    Li, Perry Y.

    to an irregular chamber volume, the surface area to volume ratio in the gas chamber can be maximized using process and enables efficient energy storage through gas compression. Current applications involving motors, typically utilize mechanical methods of sealing the gas while changing the volume

  20. The impact of skull bone intensity on the quality of compressed CT neuro images

    E-Print Network [OSTI]

    Wang, Zhou

    - tation, SSIM, compression ratio, image quality. 1. INTRODUCTION Due to the recent advances of medical being generated. Medical communities around the world have recognized the need for efficient storage, transmission and display of medical images. For example, the Canadian Association of Radiologists (CAR) has

  1. A Numerical Method for Two Phase Flow Consisting of Separate Compressible and

    E-Print Network [OSTI]

    Soatto, Stefano

    can be limiting because of the di#11;erence in sound speed between the liquid phase and gas phases mixing of liquids. We use the level set method to track the interface between the compressible and incom with large density ratios, e.g. the combustion of fuel droplets or the shock induced mixing of liquids

  2. Blowing Ratio Effects on Film Cooling Effectiveness

    E-Print Network [OSTI]

    Liu, Kuo-Chun

    2010-01-14T23:59:59.000Z

    cooling Rib turbulators Shaped internal cooling passage Trailing edge ejection Cooling air 3 Among the variety of film cooling hole designs, compound angle and shaped holes are generally considered in modern high pressure and high temperature gas turbine... ratio of 1.85. As compared to cylindrical hole, both shaped holes showed significant improved thermal protection of the surface downstream of the ejection location. Yu et al. [7] studied film cooling effectiveness and heat transfer distributions on a...

  3. Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons

    E-Print Network [OSTI]

    Tsien, Roger Y.

    Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons ABSTRACT A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video

  4. TECHNOLOGIES TO ENHANCE THE OPERATION OF EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE

    SciTech Connect (OSTI)

    Anthony J. Smalley; Ralph E. Harris; Gary D. Bourn; Ford A. Phillips; Danny M. Deffenbaugh

    2006-05-31T23:59:59.000Z

    This project has documented and demonstrated the feasibility of technologies and operational choices for companies who operate the large installed fleet of integral engine compressors in pipeline service. Continued operations of this fleet is required to meet the projected growth of the U.S. gas market. Applying project results will meet the goals of the DOE-NETL Natural Gas Infrastructure program to enhance integrity, extend life, improve efficiency, and increase capacity, while managing NOx emissions. These benefits will translate into lower cost, more reliable gas transmission, and options for increasing deliverability from the existing infrastructure on high demand days. The power cylinders on large bore slow-speed integral engine/compressors do not in general combust equally. Variations in cylinder pressure between power cylinders occur cycle-to-cycle. These variations affect both individual cylinder performance and unit average performance. The magnitude of the variations in power cylinder combustion is dependent on a variety of parameters, including air/fuel ratio. Large variations in cylinder performance and peak firing pressure can lead to detonation and misfires, both of which can be damaging to the unit. Reducing the variation in combustion pressure, and moving the high and low performing cylinders closer to the mean is the goal of engine balancing. The benefit of improving the state of the engine ''balance'' is a small reduction in heat rate and a significant reduction in both crankshaft strain and emissions. A new method invented during the course of this project is combustion pressure ratio (CPR) balancing. This method is more effective than current methods because it naturally accounts for differences in compression pressure, which results from cylinder-to-cylinder differences in the amount of air flowing through the inlet ports and trapped at port closure. It also helps avoid compensation for low compression pressure by the addition of excess fuel to achieve equalizing peak firing pressure, even if some of the compression pressure differences are attributed to differences in cylinder and piston geometry, clearance, and kinematics. The combination of high-pressure fuel injection and turbocharging should produce better mixing of fuel and air in lean mixtures. Test results documented modest improvements in heat rate and efficiency and significant improvements in emissions. The feasibility of a closed-loop control of waste-gate setting, which will maintain an equivalence ratio set point, has been demonstrated. This capability allows more direct tuning to enhance combustion stability, heat rate, or emissions. The project has documented the strong dependence of heat rate on load. The feasibility of directly measuring power and torque using the GMRC Rod Load Monitor (RLM) has been demonstrated. This capability helps to optimize heat rate while avoiding overload. The crankshaft Strain Data Capture Module (SDCM) has shown the sensitivity to changes in operating conditions and how they influence crankshaft bending strain. The results indicate that: balancing reduces the frequency of high-strain excursions, advanced timing directly increases crankshaft dynamic strain, reduced speed directly reduces strain, and high-pressure fuel injection reduces crankshaft strain slightly. The project demonstrated that when the timing is advanced, the heat rate is reduced, and when the timing is retarded, the heat rate is increased. One reason why timing is not advanced as much as it might be is the potential for detonation on hot days. A low-cost knock detector was demonstrated that allowed active control to use timing to allow the heat rate benefit to be realized safely. High flow resistance losses in the pulsation control systems installed on some compressors have been shown to hurt efficiency of both compressor and engine/compressor system. Improved pulsation control systems have the potential to recover almost 10% of available engine power. Integrity enhancements and reduced component failure probability will enhance aggregate

  5. Remote monitoring of a model levee constructed on soft peaty organic soil

    E-Print Network [OSTI]

    Reinert, Edward T; Lemke, John; Stewart, Jonathan P; Brandenberg, Scott J

    2013-01-01T23:59:59.000Z

    the compression index (C ? /C c ), and high initialpeat, high ratios of the index of secondary compression to

  6. A rapid compression machine study of the oxidation of propane in the negative temperature coefficient regime

    SciTech Connect (OSTI)

    Gallagher, S.M.; Curran, H.J.; Metcalfe, W.K.; Healy, D.; Simmie, J.M. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland); Bourque, G. [Rolls-Royce Canada, Montreal (Canada)

    2008-04-15T23:59:59.000Z

    The oxidation of propane has been studied in the temperature range 680-970 K at compressed gas pressures of 21, 27, and 37 atm and at varying equivalence ratios of 0.5, 1.0, and 2.0. These data are consistent with other experiments presented in the literature for alkane fuels in that, when ignition delay times are plotted as a function of temperature, a characteristic negative coefficient behavior is observed. In addition, these data were simulated using a detailed chemical kinetic model. It was found that qualitatively the model correctly simulated the effect of change in equivalence ratio and pressure, predicting that fuel-rich, high-pressure mixtures ignite fastest, while fuel-lean, low-pressure mixtures ignite slowest. Moreover, reactivity as a function of temperature is well captured, with the model predicting negative temperature coefficient behavior similar to the experiments. Quantitatively the model is faster than experiment for all mixtures at the lowest temperatures (650-750 K) and is also faster than experiment throughout the entire temperature range for fuel-lean mixtures. (author)

  7. An Efficient Technique for Text Compression

    E-Print Network [OSTI]

    Azad, Md Abul Kalam; Ahmad, Shabbir; Kamruzzaman, S M

    2010-01-01T23:59:59.000Z

    For storing a word or the whole text segment, we need a huge storage space. Typically a character requires 1 Byte for storing it in memory. Compression of the memory is very important for data management. In case of memory requirement compression for text data, lossless memory compression is needed. We are suggesting a lossless memory requirement compression method for text data compression. The proposed compression method will compress the text segment or the text file based on two level approaches firstly reduction and secondly compression. Reduction will be done using a word lookup table not using traditional indexing system, then compression will be done using currently available compression methods. The word lookup table will be a part of the operating system and the reduction will be done by the operating system. According to this method each word will be replaced by an address value. This method can quite effectively reduce the size of persistent memory required for text data. At the end of the first l...

  8. Progressive Compression of Volumetric Subdivision Meshes

    SciTech Connect (OSTI)

    Laney, D; Pascucci, V

    2004-04-16T23:59:59.000Z

    We present a progressive compression technique for volumetric subdivision meshes based on the slow growing refinement algorithm. The system is comprised of a wavelet transform followed by a progressive encoding of the resulting wavelet coefficients. We compare the efficiency of two wavelet transforms. The first transform is based on the smoothing rules used in the slow growing subdivision technique. The second transform is a generalization of lifted linear B-spline wavelets to the same multi-tier refinement structure. Direct coupling with a hierarchical coder produces progressive bit streams. Rate distortion metrics are evaluated for both wavelet transforms. We tested the practical performance of the scheme on synthetic data as well as data from laser indirect-drive fusion simulations with multiple fields per vertex. Both wavelet transforms result in high quality trade off curves and produce qualitatively good coarse representations.

  9. In-situ neutron diffraction of LaCoO? perovskite under uniaxial compression. I. Crystal structure analysis and texture development

    SciTech Connect (OSTI)

    Aman, Amjad; Orlovskaya, Nina, E-mail: Nina.Orlovskaya@ucf.edu [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Chen, Yan [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Chemical and Engineering Materials Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Lugovy, Mykola [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Institute for Problems of Materials Science, Kiev 03142 (Ukraine); Reece, Michael J. [The School of Engineering and Materials Science, Queen Mary, University of London, London E1 4NS (United Kingdom); Ma, Dong; Stoica, Alexandru D.; An, Ke [Chemical and Engineering Materials Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-07-07T23:59:59.000Z

    The dynamics of texture formation, changes in crystal structure, and stress accommodation mechanisms have been studied in perovskite-type R3?c rhombohedral LaCoO? during uniaxial compression using in-situ neutron diffraction. The in-situ neutron diffraction revealed the complex crystallographic changes causing the texture formation and significant straining along certain crystallographic directions during compression, which are responsible for the appearance of hysteresis and non-linear ferroelastic deformation in the LaCoO? perovskite. The irreversible strain after the first loading was connected with the appearance of non-recoverable changes in the intensity ratio of certain crystallographic peaks, causing non-reversible texture formation. However, in the second loading/unloading cycle, the hysteresis loop was closed and no further irrecoverable strain appeared after deformation. The significant texture formation is responsible for an increase in the Young's modulus of LaCoO? at high compressive stresses, ranging from 76 GPa at the very beginning of the loading to 194 GPa at 900 MPa at the beginning of the unloading curve.

  10. Proton radiography of a shock-compressed target

    SciTech Connect (OSTI)

    Ravasio, A.; Benuzzi-Mounaix, A.; Loupias, B.; Ozaki, N.; Vinci, T.; Koenig, M. [Laboratoire pour l'Utilisation des Lasers Intenses, UMR 7605, CNRS-CEA-Universite Paris VI-Ecole Polytechnique, 91128 Palaiseau Cedex (France); Romagnani, L.; Cecchetti, C.; Borghesi, M. [School of Mathematics and Physics, The Queen's University of Belfast, Belfast BT7 INN (United Kingdom); Le Pape, S.; Hicks, D.; MacKinnon, A.; Park, H. S.; Patel, P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Batani, D.; Dezulian, R. [Dipartimento di Fisica G. Occhialini, Universita di Milano-Bicocca, Piazza Della Scienze 3, 20126 Milano (Italy); Boehly, T. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Gremillet, L.; Henry, E. [CEA, DAM, DIF, F-91297 Arpajon Cedex (France); Schiavi, A. [Department of Energetics, University of Rome 'La Sapienza' Rome (Italy)

    2010-07-15T23:59:59.000Z

    In this paper we report on the radiography of a shock-compressed target using laser produced proton beams. A low-density carbon foam target was shock compressed by long pulse high-energy laser beams. The shock front was transversally probed with a proton beam produced in the interaction of a high intensity laser beam with a gold foil. We show that from radiography data, the density profile in the shocked target can be deduced using Monte Carlo simulations. By changing the delay between long and short pulse beams, we could probe different plasma conditions and structures, demonstrating that the details of the steep density gradient can be resolved. This technique is validated as a diagnostic for the investigation of warm dense plasmas, allowing an in situ characterization of high-density contrasted plasmas.

  11. Ultra-high speed vacuum pump system with first stage turbofan and second stage turbomolecular pump

    DOE Patents [OSTI]

    Jostlein, Hans

    2006-04-04T23:59:59.000Z

    An ultra-high speed vacuum pump evacuation system includes a first stage ultra-high speed turbofan and a second stage conventional turbomolecular pump. The turbofan is either connected in series to a chamber to be evacuated, or is optionally disposed entirely within the chamber. The turbofan employs large diameter rotor blades operating at high linear blade velocity to impart an ultra-high pumping speed to a fluid. The second stage turbomolecular pump is fluidly connected downstream from the first stage turbofan. In operation, the first stage turbofan operates in a pre-existing vacuum, with the fluid asserting only small axial forces upon the rotor blades. The turbofan imparts a velocity to fluid particles towards an outlet at a high volume rate, but moderate compression ratio. The second stage conventional turbomolecular pump then compresses the fluid to pressures for evacuation by a roughing pump.

  12. Industrial Compressed Air System Energy Efficiency Guidebook.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    1993-12-01T23:59:59.000Z

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

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

    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'tOriginEducationVideoStrategic|IndustrialCenterMarch 4; RSVP byof EnergyofProjectinGasoline

  14. Effect of Compression Ratio and Piston Geometry on RCCI load limit |

    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 Your Destiny:RevisedAdvisory Board Contributionsreduction systemParticulate Filters

  15. The Effects of Fuel Composition and Compression Ratio on Thermal Efficiency

    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'tOriginEducationVideoStrategic| DepartmentDepartmentThe DoDSmallManagementTechnology onThe

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

    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), GeothermalGrid Integration0-1HAWAI'I CLEANDepartment of Energy in

  17. Compressed Air Energy Storage Act (Kansas)

    Broader source: Energy.gov [DOE]

    This act lays out regulations for the local authorities related to site selection, design, operation and monitoring for underground storage of compressed air.

  18. CULTURAL RATCHETING RESULTS PRIMARILY FROM SEMANTIC COMPRESSION

    E-Print Network [OSTI]

    Bryson, Joanna J.

    CULTURAL RATCHETING RESULTS PRIMARILY FROM SEMANTIC COMPRESSION JOANNA J. BRYSON Artificial Models that cultural ratcheting requires the communication of beliefs about #12;hypotheses. Clearly, cultural

  19. Optimization Online - Compressed Sensing Off the Grid

    E-Print Network [OSTI]

    Gongguo Tang

    2012-09-13T23:59:59.000Z

    Sep 13, 2012 ... Compressed Sensing Off the Grid. Gongguo Tang(gtang5 ***at*** wisc.edu) Badri Narayan Bhaskar(bnbhaskar ***at*** wisc.edu) Parikshit ...

  20. Observation of Enhanced Transformer Ratio in Collinear Wakefield Acceleration

    SciTech Connect (OSTI)

    Jing, C.; Kanareykin, A.; Schoessow, P. [Euclid Techlabs LLC, Solon, Ohio 44139 (United States); Power, J. G.; Conde, M.; Yusof, Z.; Gai, W. [High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois-60439 (United States)

    2007-04-06T23:59:59.000Z

    One approach to future high energy particle accelerators is based on the wakefield principle: a leading high-charge drive bunch is used to excite fields in an accelerating structure or plasma that in turn accelerates a trailing low-charge witness bunch. The transformer ratio R is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss of the drive bunch. In general, R<2 for this configuration. A number of techniques have been proposed to overcome the transformer ratio limitation. We report here the first experimental study of the ramped bunch train (RBT) technique in a dielectric based accelerating structure. A single drive bunch was replaced by two bunches with charge ratio of 1 ratio 2.5 and a separation of 10.5 wavelengths of the fundamental mode. An average measured transformer ratio enhancement by a factor of 1.31 over the single drive bunch case was obtained.

  1. Experimental study and chemical analysis of n-heptane homogeneous charge compression ignition combustion with port injection of reaction inhibitors

    SciTech Connect (OSTI)

    Lue, Xingcai; Ji, Libin; Zu, Linlin; Hou, Yuchun; Huang, Cheng; Huang, Zhen [School of Mechanical and Power Engineering, Shanghai Jiaotong University, Shanghai (China)

    2007-05-15T23:59:59.000Z

    The control of ignition timing in the homogeneous charge compression ignition (HCCI) of n-heptane by port injection of reaction inhibitors was studied in a single-cylinder engine. Four suppression additives, methanol, ethanol, isopropanol, and methyl tert-butyl ether (MTBE), were used in the experiments. The effectiveness of inhibition of HCCI combustion with various additives was compared under the same equivalence ratio of total fuel and partial equivalence ratio of n-heptane. The experimental results show that the suppression effectiveness increases in the order MTBE < isopropanol << ethanol < methanol. But ethanol is the best additive when the operating ranges, indicated thermal efficiency, and emissions are considered. For ethanol/n-heptane HCCI combustion, partial combustion may be observed when the mole ratio of ethanol to that of total fuel is larger than 0.20; misfires occur when the mole ratio of ethanol to that of total fuel larger than 0.25. Moreover, CO emissions strongly depend on the maximum combustion temperature, while HC emissions are mainly dominated by the mole ratio of ethanol to that of total fuel. To obtain chemical mechanistic informations relevant to the ignition behavior, detailed chemical kinetic analysis was conducted. The simulated results also confirmed the retarding of the ignition timing by ethanol addition. In addition, it can be found from the simulation that HCHO, CO, and C{sub 2}H{sub 5}OH could not be oxidized completely and are maintained at high levels if the partial combustion or misfire occurs (for example, for leaner fuel/air mixture). (author)

  2. Abstract--A novel compressed air energy storage system for wind turbine is proposed. It captures excess power prior to

    E-Print Network [OSTI]

    Li, Perry Y.

    Abstract-- A novel compressed air energy storage system for wind turbine is proposed. It captures instead of supply. Energy is stored in a high pressure dual chamber liquid-compressed air storage vessel a challenge. An energy storage system can provide steady and predictable power by storing excess energy

  3. Low-pressure-ratio regenerative exhaust-heated gas turbine

    SciTech Connect (OSTI)

    Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

    1991-01-01T23:59:59.000Z

    A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

  4. FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS

    E-Print Network [OSTI]

    Baskurt, Atilla

    FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS �ric Guérin, �ric Tosan and Atilla, or images) with fractal models is an important center of interest for research. The general inverse problem.The most known of them is the fractal image compression method introduced by Jacquin. Generally speaking

  5. Defect Analysis of Vehicle Compressed Natural Gas

    E-Print Network [OSTI]

    Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder A China Paper on Type 4;Industrial Computed Tomography (CT) Examination of Composite Gas Cylinder #12;CT of 01-01 Layer at 4.8MPa during the gas compressing and releasing processes are the direct causes for liner defect - Since

  6. The Spatial Scaling Laws of Compressible Turbulence

    E-Print Network [OSTI]

    Sun, Bohua

    2015-01-01T23:59:59.000Z

    This Letter proposed spatial scaling laws of the density-weighted energy spectrum of compressible flow in terms of dissipation rate, wave number and the Mach number. The study has shown the compressible turbulence energy spectrum does not show the complete similarity, but incomplete similarity as $E(k,Ma)=(C+\\frac{D}{\\ln{Ma}})\

  7. Compressible fluid model for hydrodynamic lubrication cavitation

    E-Print Network [OSTI]

    Sart, Remi

    Compressible fluid model for hydrodynamic lubrication cavitation G. Bayada L. Chupin I.C.J. UMR.chupin@math.univ-bpclermont.fr Keywords: cavitation, compressible Reynolds equation Date: april 2013 Summary In this paper, it is shown how vaporous cavitation in lubricant films can be modelled in a physically justified manner through

  8. Revealing the potential of Compressed Earth Blocks : a visual narration

    E-Print Network [OSTI]

    Rabie, Omar

    2008-01-01T23:59:59.000Z

    Compressed Earth Blocks (CEB) is a developed earth technology, in which unbaked brick is produced by compressing raw soil using manual, hydraulic, or mechanical compressing machines. Revealing the potential of an affordable ...

  9. Wavelet compression for unsteady CFD data Oxford University Computing Laboratory

    E-Print Network [OSTI]

    Giles, Mike

    in compressing the periodic data arising from 3D stator/rotor and utter applications. 1 #12;1 Fourier compression compression can only be performed as a post-processing step. Also, the reconstruction at a particular instant

  10. Compressed bitmap indices for efficient query processing

    SciTech Connect (OSTI)

    Wu, Kesheng; Otoo, Ekow; Shoshani, Arie

    2001-09-30T23:59:59.000Z

    Many database applications make extensive use of bitmap indexing schemes. In this paper, we study how to improve the efficiencies of these indexing schemes by proposing new compression schemes for the bitmaps. Most compression schemes are designed primarily to achieve good compression. During query processing they can be orders of magnitude slower than their uncompressed counterparts. The new schemes are designed to bridge this performance gap by reducing compression effectiveness and improving operation speed. In a number of tests on both synthetic data and real application data, we found that the new schemes significantly outperform the well-known compression schemes while using only modestly more space. For example, compared to the Byte-aligned Bitmap Code, the new schemes are 12 times faster and it uses only 50 percent more space. The new schemes use much less space(<30 percent) than the uncompressed scheme and are faster in a majority of the test cases.

  11. Secure Compressed Reading in Smart Grids

    E-Print Network [OSTI]

    Cai, Sheng; Chen, Minghua; Yan, Jianxin; Jaggi, Sidharth

    2012-01-01T23:59:59.000Z

    Smart Grids measure energy usage in real-time and tailor supply and delivery accordingly, in order to improve power transmission and distribution. For the grids to operate effectively, it is critical to collect readings from massively-installed smart meters to control centers in an efficient and secure manner. In this paper, we propose a secure compressed reading scheme to address this critical issue. We observe that our collected real-world meter data express strong temporal correlations, indicating they are sparse in certain domains. We adopt Compressed Sensing technique to exploit this sparsity and design an efficient meter data transmission scheme. Our scheme achieves substantial efficiency offered by compressed sensing, without the need to know beforehand in which domain the meter data are sparse. This is in contrast to traditional compressed-sensing based scheme where such sparse-domain information is required a priori. We then design specific dependable scheme to work with our compressed sensing based ...

  12. Quantum Data Compression of a Qubit Ensemble

    E-Print Network [OSTI]

    Lee A. Rozema; Dylan H. Mahler; Alex Hayat; Peter S. Turner; Aephraim M. Steinberg

    2014-10-15T23:59:59.000Z

    Data compression is a ubiquitous aspect of modern information technology, and the advent of quantum information raises the question of what types of compression are feasible for quantum data, where it is especially relevant given the extreme difficulty involved in creating reliable quantum memories. We present a protocol in which an ensemble of quantum bits (qubits) can in principle be perfectly compressed into exponentially fewer qubits. We then experimentally implement our algorithm, compressing three photonic qubits into two. This protocol sheds light on the subtle differences between quantum and classical information. Furthermore, since data compression stores all of the available information about the quantum state in fewer physical qubits, it could provide a vast reduction in the amount of quantum memory required to store a quantum ensemble, making even today's limited quantum memories far more powerful than previously recognized.

  13. Dynamic compression of synthetic diamond windows (final report for LDRD project 93531).

    SciTech Connect (OSTI)

    Dolan, Daniel H.,

    2008-09-01T23:59:59.000Z

    Diamond is an attractive dynamic compression window for many reasons: high elastic limit,large mechanical impedance, and broad transparency range. Natural diamonds, however, aretoo expensive to be used in destructive experiments. Chemical vapor deposition techniquesare now able to produce large single-crystal windows, opening up many potential dynamiccompression applications. This project studied the behavior of synthetic diamond undershock wave compression. The results suggest that synthetic diamond could be a usefulwindow in this field, though complete characterization proved elusive.3

  14. Compression molding of aerogel microspheres

    DOE Patents [OSTI]

    Pekala, R.W.; Hrubesh, L.W.

    1998-03-24T23:59:59.000Z

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner is disclosed. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50--800 kg/m{sup 3} (0.05--0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization. 4 figs.

  15. Compression molding of aerogel microspheres

    DOE Patents [OSTI]

    Pekala, Richard W. (Pleasant Hill, CA); Hrubesh, Lawrence W. (Pleasanton, CA)

    1998-03-24T23:59:59.000Z

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50-800 kg/m.sup.3 (0.05-0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization.

  16. Shock waves in a Z-pinch and the formation of high energy density plasma

    SciTech Connect (OSTI)

    Rahman, H. U. [Magneto-Inertial Fusion Technologies Inc. (MIFTI), Irvine, California 92612 (United States) and Department of Physics, University of California Irvine, Irvine, California 92697 (United States); Wessel, F. J. [Department of Physics, University of California Irvine, Irvine California 92697 (United States); Ney, P. [Mount San Jacinto College, Menifee, California 92584 (United States); Presura, R. [University of Nevada, Reno, 1664 N. Virginia St., Reno, Nevada 89557-0208 (United States); Ellahi, Rahmat [Department of Mathematics and Statistics, FBAS, IIU, Islamabad (Pakistan) and Department of Mechanical Engineering, University of California Riverside, Riverside, California 92521 (United States); Shukla, P. K. [Department of Mechanical and Aerospace Engineering and Center for Energy Research, University of California San Diego, La Jolla, California 92093 (United States)

    2012-12-15T23:59:59.000Z

    A Z-pinch liner, imploding onto a target plasma, evolves in a step-wise manner, producing a stable, magneto-inertial, high-energy-density plasma compression. The typical configuration is a cylindrical, high-atomic-number liner imploding onto a low-atomic-number target. The parameters for a terawatt-class machine (e.g., Zebra at the University of Nevada, Reno, Nevada Terawatt Facility) have been simulated. The 2-1/2 D MHD code, MACH2, was used to study this configuration. The requirements are for an initial radius of a few mm for stable implosion; the material densities properly distributed, so that the target is effectively heated initially by shock heating and finally by adiabatic compression; and the liner's thickness adjusted to promote radial current transport and subsequent current amplification in the target. Since the shock velocity is smaller in the liner, than in the target, a stable-shock forms at the interface, allowing the central load to accelerate magnetically and inertially, producing a magneto-inertial implosion and high-energy density plasma. Comparing the implosion dynamics of a low-Z target with those of a high-Z target demonstrates the role of shock waves in terms of compression and heating. In the case of a high-Z target, the shock wave does not play a significant heating role. The shock waves carry current and transport the magnetic field, producing a high density on-axis, at relatively low temperature. Whereas, in the case of a low-Z target, the fast moving shock wave preheats the target during the initial implosion phase, and the later adiabatic compression further heats the target to very high energy density. As a result, the compression ratio required for heating the low-Z plasma to very high energy densities is greatly reduced.

  17. Assessing the Effects of Data Compression in Simulations Using Physically Motivated Metrics

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

    Laney, Daniel; Langer, Steven; Weber, Christopher; Lindstrom, Peter; Wegener, Al

    2014-01-01T23:59:59.000Z

    This paper examines whether lossy compression can be used effectively in physics simulations as a possible strategy to combat the expected data-movement bottleneck in future high performance computing architectures. We show that, for the codes and simulations we tested, compression levels of 3–5X can be applied without causing significant changes to important physical quantities. Rather than applying signal processing error metrics, we utilize physics-based metrics appropriate for each code to assess the impact of compression. We evaluate three different simulation codes: a Lagrangian shock-hydrodynamics code, an Eulerian higher-order hydrodynamics turbulence modeling code, and an Eulerian coupled laser-plasma interaction code. Wemore »compress relevant quantities after each time-step to approximate the effects of tightly coupled compression and study the compression rates to estimate memory and disk-bandwidth reduction. We find that the error characteristics of compression algorithms must be carefully considered in the context of the underlying physics being modeled.« less

  18. Fact Sheet: Isothermal Compressed Air Energy Storage (October...

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

    SustainX American Recovery and Reinvestment Act (ARRA) Isothermal Compressed Air Energy Storage Demonstrating a modular, market-ready energy storage system that uses compressed air...

  19. Advancement in Fuel Spray and Combustion Modeling for Compression...

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

    Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine...

  20. Graphene physics and insulator-metal transition in compressed...

    Office of Scientific and Technical Information (OSTI)

    Graphene physics and insulator-metal transition in compressed hydrogen Citation Details Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors:...

  1. New Methodologies for Analysis of Premixed Charge Compression...

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

    New Methodologies for Analysis of Premixed Charge Compression Ignition Engines New Methodologies for Analysis of Premixed Charge Compression Ignition Engines Presentation given at...

  2. Characterization of Dual-Fuel Reactivity Controlled Compression...

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

    Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel Characterization of Dual-Fuel Reactivity Controlled Compression Ignition (RCCI)...

  3. Regulated Emissions from Diesel and Compressed Natural Gas Transit...

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

    Emissions from Diesel and Compressed Natural Gas Transit Buses Regulated Emissions from Diesel and Compressed Natural Gas Transit Buses Poster presentaiton at the 2007 Diesel...

  4. Open Issues in the Development of Safety Standards for Compressed...

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

    Issues in the Development of Safety Standards for Compressed Hydrogen Storage at SAE-International Open Issues in the Development of Safety Standards for Compressed Hydrogen...

  5. Research and Development Strategies for Compressed & Cryo-Hydrogen...

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

    Strategies for Compressed & Cryo-Hydrogen Storage Systems - Workshop Summary Report Research and Development Strategies for Compressed & Cryo-Hydrogen Storage Systems - Workshop...

  6. 2013 Hydrogen Compression, Storage, and Dispensing Cost Reduction...

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

    Hydrogen Compression, Storage, and Dispensing Cost Reduction Workshop Final Report 2013 Hydrogen Compression, Storage, and Dispensing Cost Reduction Workshop Final Report...

  7. Evaluation of the Compressed Air Challenge Training Program:...

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

    Executive Summary Evaluation of the Compressed Air Challenge Training Program: Executive Summary This is the executive summary of a report on an evaluation of the Compressed Air...

  8. Evaluation of the Compressed Air Challenge Training Program:...

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

    Final Report Evaluation of the Compressed Air Challenge Training Program: Final Report This is the final report on an evaluation of the Compressed Air Challenge (CAC) training...

  9. Effect of Premixed Charge Compression Ignition on Vehicle Fuel...

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

    Premixed Charge Compression Ignition on Vehicle Fuel Economy and Emissions Reduction over Transient Driving Cycles Effect of Premixed Charge Compression Ignition on Vehicle Fuel...

  10. DOE Announces Webinars on Compressed Natural Gas Infrastructure...

    Energy Savers [EERE]

    Compressed Natural Gas Infrastructure, an Advanced Rooftop Unit Campaign, and More DOE Announces Webinars on Compressed Natural Gas Infrastructure, an Advanced Rooftop Unit...

  11. NJ Compressed Natural Gas Refuse Trucks, Shuttle Buses and Infrastruct...

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

    Documents & Publications CX-005345: Categorical Exclusion Determination NJ Compressed Natural Gas Refuse Trucks, Shuttle Buses and Infrastructure Business Case for Compressed...

  12. Workshop Agenda: Compressed Natural Gas and Hydrogen Fuels, Lesssons...

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

    Agenda: Compressed Natural Gas and Hydrogen Fuels, Lesssons Learned for the Safe Deployment of Vehicles Workshop Agenda: Compressed Natural Gas and Hydrogen Fuels, Lesssons Learned...

  13. H2A Delivery: Forecourt Compression & Storage Optimization (Part...

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

    H2A Delivery: Forecourt Compression & Storage Optimization (Part II) H2A Delivery: Forecourt Compression & Storage Optimization (Part II) Presentation by Matthew Hooks of TIAX at...

  14. H2A Delivery: Forecourt Compression & Storage Optimization (Part...

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

    H2A Delivery: H2A Delivery: Forecourt Compression & Forecourt Compression & Storage Optimization (Part II) Storage Optimization (Part II) Hydrogen Delivery Analysis Meeting May...

  15. Technical Assessment of Cryo-Compressed Hydrogen Storage Tank...

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

    Cryo-Compressed Hydrogen Storage Tank Systems for Automotive Applications Technical Assessment of Cryo-Compressed Hydrogen Storage Tank Systems for Automotive Applications...

  16. Technical Assessment of Compressed Hydrogen Storage Tank Systems...

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

    Compressed Hydrogen Storage Tank Systems for Automotive Applications Technical Assessment of Compressed Hydrogen Storage Tank Systems for Automotive Applications Technical report...

  17. Pdc - The Worldwide Leader in Hydrogen Refueling Station Compression...

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

    Pdc - The Worldwide Leader in Hydrogen Refueling Station Compression Pdc - The Worldwide Leader in Hydrogen Refueling Station Compression This presentation by Matther Weaver of Pdc...

  18. UNCORRECTEDPROOF 2 Compression behavior of porous NiTi shape memory alloy

    E-Print Network [OSTI]

    Taya, Minoru

    Ti by self-propagating 41high temperature synthesis (SHS), and again the porous 42NiTi fabricated. The compression behavior of the 11 porous NiTi was examined with the aim of using it possibly as a high energy for possible application 30 in medical implant devices and as high energy absorp- 31 tion structural material

  19. Shock compression experiments on Lithium Deuteride single crystals.

    SciTech Connect (OSTI)

    Knudson, Marcus D.; Desjarlais, Michael P.; Lemke, Raymond W.

    2014-10-01T23:59:59.000Z

    S hock compression exper iments in the few hundred GPa (multi - Mabr) regime were performed on Lithium Deuteride (LiD) single crystals . This study utilized the high velocity flyer plate capability of the Sandia Z Machine to perform impact experiments at flyer plate velocities in the range of 17 - 32 km/s. Measurements included pressure, density, and temperature between ~200 - 600 GPa along the Principal Hugoniot - the locus of end states achievable through compression by large amplitude shock waves - as well as pressure and density of re - shock states up to ~900 GPa . The experimental measurements are compared with recent density functional theory calculations as well as a new tabular equation of state developed at Los Alamos National Labs.

  20. Explosive flux compression generators for rail gun power sources

    SciTech Connect (OSTI)

    Fowler, C.M.; Peterson, D.R.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; King, J.C.

    1980-01-01T23:59:59.000Z

    A class of explosive magnetic flux compression generators is described that has been used successfully to power rail guns. A program to increase current magnitudes and pulse lengths is outlined. Various generator loss terms are defined and plans to overcome some of them are discussed. Included are various modifications of the conventional strip generators that are more resistant to undesirable expansion of generator components from magnetic forces. Finally, an integral rail gun is discussed that has coaxial geometry. Integral rail guns utilize the rails themselves as flux compression generator elements and, under ideal conditions, are theoretically capable of driving projectiles to arbitrarily high velocities. Integral coaxial rail guns should be superior in some regards to their square bore counterparts.

  1. aspect ratio silicon: Topics by E-print Network

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

    silicon-nitride hard-mask for high aspect-ratio silicon fins V. Jovanovi, S, Zagreb, Croatia Abstract - A method for using hard-masks to achieve sub- 100 nm patterning of...

  2. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect (OSTI)

    Lee C. Cadwallader

    2004-09-01T23:59:59.000Z

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air, and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard assoicated with compressed gas cylinders and mthods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  3. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect (OSTI)

    Cadwallader, L.C. [Idaho National Engineering and Environmental Laboratory (United States)

    2005-05-15T23:59:59.000Z

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard associated with compressed gas cylinders and methods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  4. Autoignition of toluene and benzene at elevated pressures in a rapid compression machine

    SciTech Connect (OSTI)

    Mittal, Gaurav; Sung, Chih-Jen [Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States)

    2007-09-15T23:59:59.000Z

    Autoignition of toluene and benzene is investigated in a rapid compression machine at conditions relevant to HCCI (homogeneous charge compression ignition) combustion. Experiments are conducted for homogeneous mixtures over a range of equivalence ratios at compressed pressures from 25 to 45 bar and compressed temperatures from 920 to 1100 K. Experiments varying oxygen concentration while keeping the mole fraction of toluene constant reveal a strong influence of oxygen in promoting ignition. Additional experiments varying fuel mole fraction at a fixed equivalence ratio show that ignition delay becomes shorter with increasing fuel concentration. Moreover, autoignition of benzene shows significantly higher activation energy than that of toluene. In addition, the experimental pressure traces for toluene show behavior of heat release significantly different from the results of Davidson et al. [D.F. Davidson, B.M. Gauthier, R.K. Hanson, Proc. Combust. Inst. 30 (2005) 1175-1182]. Predictability of various detailed kinetic mechanisms is also compared. Results demonstrate that the existing mechanisms for toluene and benzene fail to predict the experimental data with respect to ignition delay and heat release. Flux analysis is further conducted to identify the dominant reaction pathways and the reactions responsible for the mismatch of experimental and simulated data. (author)

  5. Plasma Switch for High-Power Active Pulse Compressor

    SciTech Connect (OSTI)

    Hirshfield, Jay L. [Omega-P, Inc.] [Omega-P, Inc.

    2013-11-04T23:59:59.000Z

    Results are presented from experiments carried out at the Naval Research Laboratory X-band magnicon facility on a two-channel X-band active RF pulse compressor that employed plasma switches. Experimental evidence is shown to validate the basic goals of the project, which include: simultaneous firing of plasma switches in both channels of the RF circuit, operation of quasi-optical 3-dB hybrid directional coupler coherent superposition of RF compressed pulses from both channels, and operation of the X-band magnicon directly in the RF pulse compressor. For incident 1.2 ?s pulses in the range 0.63 ? 1.35 MW, compressed pulses of peak powers 5.7 ? 11.3 MW were obtained, corresponding to peak power gain ratios of 8.3 ? 9.3. Insufficient bakeout and conditioning of the high-power RF circuit prevented experiments from being conducted at higher RF input power levels.

  6. Heat pump employing optimal refrigerant compressor for low pressure ratio applications

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX)

    1982-01-01T23:59:59.000Z

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler for circulating the fluid in heat exchange relationship with a refrigerant fluid; two refrigerant heat exchangers; one for effecting the heat exchange with the fluid and a second refrigerant-heat exchange fluid heat exchanger for effecting a low pressure ratio of compression of the refrigerant; a rotary compressor for compressing the refrigerant with low power consumption at the low pressure ratio; at least one throttling valve connecting at the inlet side of heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit serially connecting the above elements; refrigerant in the circuit; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant.

  7. Analysis of Arithmetic Coding for Data Compression

    E-Print Network [OSTI]

    Howard, Paul G.; Vitter, Jeffrey Scott

    1992-01-01T23:59:59.000Z

    Arithmetic coding, in conjunction with a suitable probabilistic model, can pro- vide nearly optimal data compression. In this article we analyze the e ect that the model and the particular implementation of arithmetic ...

  8. Compressed Index for Dictionary Matching (extended abstract)

    E-Print Network [OSTI]

    Hon, Wing-Kai; Lam, Tak-Wah; Shah, Rahul; Siu-Lung, Tam; Vitter, Jeffrey Scott

    2008-01-01T23:59:59.000Z

    the kth- order empirical entropy of T, and ¾ is the size of the alphabet. In this paper we study compressed representation for another classical problem of string indexing, which is called dictionary matching in the literature. Precisely, a collection D...

  9. Ramp Compression Experiments - a Sensitivity Study

    SciTech Connect (OSTI)

    Bastea, M; Reisman, D

    2007-02-26T23:59:59.000Z

    We present the first sensitivity study of the material isentropes extracted from ramp compression experiments. We perform hydrodynamic simulations of representative experimental geometries associated with ramp compression experiments and discuss the major factors determining the accuracy of the equation of state information extracted from such data. In conclusion, we analyzed both qualitatively and quantitatively the major experimental factors that determine the accuracy of equations of state extracted from ramp compression experiments. Since in actual experiments essentially all the effects discussed here will compound, factoring out individual signatures and magnitudes, as done in the present work, is especially important. This study should provide some guidance for the effective design and analysis of ramp compression experiments, as well as for further improvements of ramp generators performance.

  10. Compressed Air Load Reduction Approaches and Innovations

    E-Print Network [OSTI]

    D'Antonio, M.; Epstein, G.; Moray, S.; Schmidt, C.

    2005-01-01T23:59:59.000Z

    are assessed. It is a common practice in facilities to simply add compressor capacity when faced with supply pressure or volume deficiencies, increasing the energy consumption associated with compressed air systems in industry. Additionally, in recent years...

  11. Sandia National Laboratories: percussive drilling with compressed...

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

    percussive drilling with compressed air Sandia and Atlas-Copco Secoroc Advance to Phase 2 in Their Geothermal Energy Project On July 31, 2013, in Energy, Geothermal, News, News &...

  12. Wavelet compression of geodetic integral operators

    E-Print Network [OSTI]

    Stuttgart, Universität

    1 Wavelet compression of geodetic integral operators W. Keller Institute of Geodesy, Universität possible wavelet approximation: · simplest possible wavelet--> Haar wavelet · decomposition depths = 0 => try better wavelet, use higher decomposition depth! For 1D application this question was studied

  13. An advanced vapor-compression desalination system 

    E-Print Network [OSTI]

    Lara Ruiz, Jorge Horacio Juan

    2006-04-12T23:59:59.000Z

    Currently, the two dominant desalination methods are reverse osmosis (RO) and multi-stage flash (MSF). RO requires large capital investment and maintenance, whereas MSF is too energy intensive. An innovative vapor-compression desalination system...

  14. Seneca Compressed Air Energy Storage (CAES) Project

    SciTech Connect (OSTI)

    None

    2012-11-30T23:59:59.000Z

    This document provides specifications for the process air compressor for a compressed air storage project, requests a budgetary quote, and provides supporting information, including compressor data, site specific data, water analysis, and Seneca CAES value drivers.

  15. Compressing measurements in quantum dynamic parameter estimation

    E-Print Network [OSTI]

    Magesan, Easwar

    We present methods that can provide an exponential savings in the resources required to perform dynamic parameter estimation using quantum systems. The key idea is to merge classical compressive sensing techniques with ...

  16. Compression and Creep of Venice Lagoon Sands

    E-Print Network [OSTI]

    Sanzeni, Alex

    A laboratory test program was conducted to evaluate the one-dimensional (1D) compression and creep properties of intact sand (and silty-sand) samples from a deep borehole at the Malamocco Inlet to the Venice Lagoon. The ...

  17. Dictionary Design for Distributed Compressive Sensing

    E-Print Network [OSTI]

    Chen, Wei; Wassell, Ian J.; Rodrigues, Miguel R. D.

    2014-08-20T23:59:59.000Z

    -signal correlation; and iii) inter-signal correlation. Simulation results showthat our dictionary design leads to an improved DCS reconstruction performance in com- parison to other designs. Index Terms— Compressive sensing, dictionary learning, dis- tributed... 1Dictionary Design for Distributed Compressive Sensing Wei Chen, Member, IEEE and Ian J. Wassell and Miguel R. D. Rodrigues, Member, IEEE Abstract—Conventional dictionary learning frameworks at- tempt to find a set of atoms that promote both signal...

  18. Compressed Indexes for Approximate String Matching

    E-Print Network [OSTI]

    Sung, Wing-Kin Ken"

    Compressed Indexes for Approximate String Matching Ho-Leung Chan1 Tak-Wah Lam1, Wing-Kin Sung2 Siu the index space to O(n log n). Huynh et al. [10] and Lam et al. [11] further compressed the index to O,wongss}@comp.nus.edu.sg Abstract. We revisit the problem of indexing a string S[1..n] to support searching all substrings

  19. Exergy Analysis of Industrial Air Compression

    E-Print Network [OSTI]

    Bader, W. T.; Kissock, J. K.

    every industrial plant as a source of exergy for tools, actuators, and a myriad of manufacturing processes. For this analysis, a typical scenario is considered with a compressor installed indoors. Conditions for the indoor surroundings... are temperature T I and pressure Ph while the outdoor conditions, the environment, are To and Po. The compressor system is defined as the compressor, dryer (aftercooler) and compressed air distribution system (piping). We assume that the compressed air exits...

  20. Energy Efficiency in Compressed Air Systems 

    E-Print Network [OSTI]

    Hingorani, A.; Pavlov, A.

    2010-01-01T23:59:59.000Z

    of transfer of energy. Typical applications in this category are motive applications, such as driving pneumatic tools and cylinders, operating instruments, pneumatic actuation and other such processes. - Active air, where the compressed air takes..., for ease. 3. MINIMIZING THE COSTS OF USAGE OF COMPRESSED AIR Within the factory, similar rules as for distribution would apply. Older factories must have their piping thoroughly checked for leakage in the pipelines. Tools such as ultrasonic leak...

  1. The Future of Image Compression William A. Pearlman

    E-Print Network [OSTI]

    compact, higher power batteries would expand application scenarios for compression · Miniaturization

  2. Wavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and Mathematical Analysis of Sign Entropy CodingAnalysi

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Wavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression.olivier@univ-poitiers.fr Abstract One of the advantages of the Discrete Wavelet Transform (DWT) compared to Fourier Transform (e

  3. DNA Compression Challenge Revisited: a Dynamic Programming Approach

    E-Print Network [OSTI]

    Lonardi, Stefano

    DNA Compression Challenge Revisited: a Dynamic Programming Approach Behshad Behzadi and Fabrice Le Fessant LIX, Ecole Polytechnique, Paris, FRANCE June 21 2005 B. Behzadi, F. Le Fessant (LIX) DNA Compression June 21 2005 1 / 38 #12;Outline 1 DNA Compression Challenge 2 Tools and Methods 3 DNA Compression

  4. Experimental Investigation of Fuel-Reactivity Controlled Compression Ignition (RCCI) Combustion Mode in a Multi-Cylinder, Light-Duty Diesel Engine

    SciTech Connect (OSTI)

    Cho, Kukwon [ORNL] [ORNL; Curran, Scott [ORNL] [ORNL; Prikhodko, Vitaly Y [ORNL] [ORNL; Sluder, Scott [ORNL] [ORNL; Parks, II, James E [ORNL; Wagner, Robert M [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    An experimental study was performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (RCCI) combustion mode utilizing dual-fuel approach in a light-duty, multi-cylinder diesel engine. In-cylinder fuel blending using port fuel injection of gasoline before intake valve opening (IVO) and early-cycle, direct injection of diesel fuel was used as the charge preparation and fuel blending strategy. In order to achieve the desired auto-ignition quality through the stratification of the fuel-air equivalence ratio ( ), blends of commercially available gasoline and diesel fuel were used. Engine experiments were performed at an engine speed of 2300rpm and an engine load of 4.3bar brake mean effective pressure (BMEP). It was found that significant reduction in both nitrogen oxide (NOx) and particulate matter (PM) was realized successfully through the RCCI combustion mode even without applying exhaust gas recirculation (EGR). However, high carbon monoxide (CO) and hydrocarbon (HC) emissions were observed. The low combustion gas temperature during the expansion and exhaust processes seemed to be the dominant source of high CO emissions in the RCCI combustion mode. The high HC emissions during the RCCI combustion mode could be due to the increased combustion quenching layer thickness as well as the -stratification at the periphery of the combustion chamber. The slightly higher brake thermal efficiency (BTE) of the RCCI combustion mode was observed than the other combustion modes, such as the conventional diesel combustion (CDC) mode, and single-fuel, premixed charge compression ignition (PCCI) combustion mode. The parametric study of the RCCI combustion mode revealed that the combustion phasing and/or the peak cylinder pressure rise rate of the RCCI combustion mode could be controlled by several physical parameters premixed ratio (rp), intake swirl intensity, and start of injection (SOI) timing of directly injected fuel unlike other low temperature combustion (LTC) strategies.

  5. Compression of Laser Radiation in Plasmas Using Electromagnetic Cascading

    SciTech Connect (OSTI)

    Kalmykov, Serguei; Shvets, Gennady [Department of Physics and Institute for Fusion Studies, University of Texas at Austin, One University Station C1500, Austin, Texas 78712 (United States)

    2005-06-17T23:59:59.000Z

    Compressing high-power laser beams in plasmas via generation of a coherent cascade of electromagnetic sidebands is described. The technique requires two copropagating beams detuned by a near-resonant frequency {omega} < or approx. {omega}{sub p}. The ponderomotive force of the laser beat wave drives an electron plasma wave which modifies the refractive index of plasma so as to produce a periodic phase modulation of the laser field with the beat period {tau}{sub b}=2{pi}/{omega}. A train of chirped laser beat notes (each of duration {tau}{sub b}) is thus created. The group velocity dispersion of radiation in plasma can then compress each beat note to a few-laser-cycle duration. As a result, a train of sharp electromagnetic spikes separated in time by {tau}{sub b} is formed. Depending on the plasma and laser parameters, chirping and compression can be implemented either concurrently in the same plasma or sequentially in different plasmas.

  6. DRIVE CYCLE EFFICIENCY AND EMISSIONS ESTIMATES FOR REACTIVITY CONTROLLED COMPRESSION IGNITION IN A MULTI-CYLINDER LIGHT-DUTY DIESEL ENGINE

    SciTech Connect (OSTI)

    Curran, Scott [ORNL; Briggs, Thomas E [ORNL; Cho, Kukwon [ORNL; Wagner, Robert M [ORNL

    2011-01-01T23:59:59.000Z

    In-cylinder blending of gasoline and diesel to achieve Reactivity Controlled Compression Ignition (RCCI) has been shown to reduce NOx and PM emissions while maintaining or improving brake thermal efficiency as compared to conventional diesel combustion (CDC). The RCCI concept has an advantage over many advanced combustion strategies in that by varying both the percent of premixed gasoline and EGR rate, stable combustion can be extended over more of the light-duty drive cycle load range. Changing the percent premixed gasoline changes the fuel reactivity stratification in the cylinder providing further control of combustion phasing and pressure rise rate than the use of EGR alone. This paper examines the combustion and emissions performance of light-duty diesel engine using direct injected diesel fuel and port injected gasoline to carry out RCCI for steady-state engine conditions which are consistent with a light-duty drive cycle. A GM 1.9L four-cylinder engine with the stock compression ratio of 17.5:1, common rail diesel injection system, high-pressure EGR system and variable geometry turbocharger was modified to allow for port fuel injection with gasoline. Engine-out emissions, engine performance and combustion behavior for RCCI operation is compared against both CDC and a premixed charge compression ignition (PCCI) strategy which relies on high levels of EGR dilution. The effect of percent of premixed gasoline, EGR rate, boost level, intake mixture temperature, combustion phasing and pressure rise rate is investigated for RCCI combustion for the light-duty modal points. Engine-out emissions of NOx and PM were found to be considerably lower for RCCI operation as compared to CDC and PCCI, while HC and CO emissions were higher. Brake thermal efficiency was similar or higher for many of the modal conditions for RCCI operation. The emissions results are used to estimate hot-start FTP-75 emissions levels with RCCI and are compared against CDC and PCCI modes.

  7. DATA COMPRESSION USING WAVELETS: ERROR ...

    E-Print Network [OSTI]

    1910-90-11T23:59:59.000Z

    fense Advanced Research Projects Agency, and the Army High Performance Computing Research. Center. 1. Department of Mathematics, University of South

  8. Weakly relativistic and ponderomotive effects on self-focusing and self-compression of laser pulses in near critical plasmas

    SciTech Connect (OSTI)

    Bokaei, B.; Niknam, A. R., E-mail: a-niknam@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)

    2014-10-15T23:59:59.000Z

    The spatiotemporal dynamics of high power laser pulses in near critical plasmas are studied taking in to account the effects of relativistic and ponderomotive nonlinearities. First, within one-dimensional analysis, the effects of initial parameters such as laser intensity, plasma density, and plasma electron temperature on the self-compression mechanism are discussed. The results illustrate that the ponderomotive nonlinearity obstructs the relativistic self-compression above a certain intensity value. Moreover, the results indicate the existence of the turning point temperature in which the compression process has its strongest strength. Next, the three-dimensional analysis of laser pulse propagation is investigated by coupling the self-focusing equation with the self-compression one. It is shown that in contrast to the case in which the only relativistic nonlinearity is considered, in the presence of ponderomotive nonlinearity, the self-compression mechanism obstructs the self-focusing and leads to an increase of the laser spot size.

  9. The Fractal Density Structure in Supersonic Isothermal Turbulence: Solenoidal versus Compressive Energy Injection

    E-Print Network [OSTI]

    Christoph Federrath; Ralf S. Klessen; Wolfram Schmidt

    2009-02-03T23:59:59.000Z

    In a systematic study, we compare the density statistics in high resolution numerical experiments of supersonic isothermal turbulence, driven by the usually adopted solenoidal (divergence-free) forcing and by compressive (curl-free) forcing. We find that for the same rms Mach number, compressive forcing produces much stronger density enhancements and larger voids compared to solenoidal forcing. Consequently, the Fourier spectra of density fluctuations are significantly steeper. This result is confirmed using the Delta-variance analysis, which yields power-law exponents beta~3.4 for compressive forcing and beta~2.8 for solenoidal forcing. We obtain fractal dimension estimates from the density spectra and Delta-variance scaling, and by using the box counting, mass size and perimeter area methods applied to the volumetric data, projections and slices of our turbulent density fields. Our results suggest that compressive forcing yields fractal dimensions significantly smaller compared to solenoidal forcing. However, the actual values depend sensitively on the adopted method, with the most reliable estimates based on the Delta-variance, or equivalently, on Fourier spectra. Using these methods, we obtain D~2.3 for compressive and D~2.6 for solenoidal forcing, which is within the range of fractal dimension estimates inferred from observations (D~2.0-2.7). The velocity dispersion to size relations for both solenoidal and compressive forcing obtained from velocity spectra follow a power law with exponents in the range 0.4-0.5, in good agreement with previous studies.

  10. Non-US data compression and coding research. FASAC Technical Assessment Report

    SciTech Connect (OSTI)

    Gray, R.M.; Cohn, M.; Craver, L.W.; Gersho, A.; Lookabaugh, T.; Pollara, F.; Vetterli, M.

    1993-11-01T23:59:59.000Z

    This assessment of recent data compression and coding research outside the United States examines fundamental and applied work in the basic areas of signal decomposition, quantization, lossless compression, and error control, as well as application development efforts in image/video compression and speech/audio compression. Seven computer scientists and engineers who are active in development of these technologies in US academia, government, and industry carried out the assessment. Strong industrial and academic research groups in Western Europe, Israel, and the Pacific Rim are active in the worldwide search for compression algorithms that provide good tradeoffs among fidelity, bit rate, and computational complexity, though the theoretical roots and virtually all of the classical compression algorithms were developed in the United States. Certain areas, such as segmentation coding, model-based coding, and trellis-coded modulation, have developed earlier or in more depth outside the United States, though the United States has maintained its early lead in most areas of theory and algorithm development. Researchers abroad are active in other currently popular areas, such as quantizer design techniques based on neural networks and signal decompositions based on fractals and wavelets, but, in most cases, either similar research is or has been going on in the United States, or the work has not led to useful improvements in compression performance. Because there is a high degree of international cooperation and interaction in this field, good ideas spread rapidly across borders (both ways) through international conferences, journals, and technical exchanges. Though there have been no fundamental data compression breakthroughs in the past five years--outside or inside the United State--there have been an enormous number of significant improvements in both places in the tradeoffs among fidelity, bit rate, and computational complexity.

  11. Nanostructure of Solid Precipitates Obtained by Expansion of Polystyrene-block-Polybutadiene Solutions in Near Critical Propane: Block Ratio and Micellar Solution Effects

    SciTech Connect (OSTI)

    Green, Jade [University of Wyoming, Laramie; Tyrrell, Zachary [University of Wyoming, Laramie; Radosz, Maciej [University of Wyoming, Laramie; Hong, Kunlun [ORNL; Mays, Jimmy [ORNL

    2011-01-01T23:59:59.000Z

    In contrast to incompressible liquid solutions, compressible near-critical solutions of block copolymers allow for controlling rapid structure transformations with pressure alone. For example, when dissolved in near-critical propane, polystyrene-block-polybutadiene can form a random molecular solution at high pressures, a micellar solution at moderate pressures, and a solvent-free precipitate at low pressures. In contrast to the unstructured virgin copolymer, such a propane-treated precipitate rapidly self-assembles toward structures characteristic of equilibrated block copolymers, such as lamellae, spheres, or cylinders, which depend on the block ratio rather than on the decompression rate or temperature, at least within the rate and temperature ranges investigated in this work. At lower temperatures, however, say below 40 C, glass transition of the styrene-butadiene diblocks can inhibit independent structure formation, while crystallization of their hydrogenated-butadiene analogues can preserve the micellar-solution structure.

  12. Interpretation of the atmospheric muon charge ratio in MINOS

    E-Print Network [OSTI]

    Philip Schreiner; Maury Goodman

    2007-06-04T23:59:59.000Z

    MINOS is the first large magnetic detector deep underground and is the first to measure the muon charge ratio with high statistics in the region near 1 TeV.\\cite{bib:adamson} An approximate formula for the muon charge ratio can be expressed in terms of $\\epsilon_\\pi$ = 115 GeV, $\\epsilon_K$ = 850 GeV and $\\ec$. The implications for K production in the atmosphere will be discussed.

  13. 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.

  14. Weather-Corrected Performance Ratio

    SciTech Connect (OSTI)

    Dierauf, T.; Growitz, A.; Kurtz, S.; Cruz, J. L. B.; Riley, E.; Hansen, C.

    2013-04-01T23:59:59.000Z

    Photovoltaic (PV) system performance depends on both the quality of the system and the weather. One simple way to communicate the system performance is to use the performance ratio (PR): the ratio of the electricity generated to the electricity that would have been generated if the plant consistently converted sunlight to electricity at the level expected from the DC nameplate rating. The annual system yield for flat-plate PV systems is estimated by the product of the annual insolation in the plane of the array, the nameplate rating of the system, and the PR, which provides an attractive way to estimate expected annual system yield. Unfortunately, the PR is, again, a function of both the PV system efficiency and the weather. If the PR is measured during the winter or during the summer, substantially different values may be obtained, making this metric insufficient to use as the basis for a performance guarantee when precise confidence intervals are required. This technical report defines a way to modify the PR calculation to neutralize biases that may be introduced by variations in the weather, while still reporting a PR that reflects the annual PR at that site given the project design and the project weather file. This resulting weather-corrected PR gives more consistent results throughout the year, enabling its use as a metric for performance guarantees while still retaining the familiarity this metric brings to the industry and the value of its use in predicting actual annual system yield. A testing protocol is also presented to illustrate the use of this new metric with the intent of providing a reference starting point for contractual content.

  15. Fixed Block Compression Boosting in FM-Indexes

    E-Print Network [OSTI]

    Kärkkäinen, Juha

    2011-01-01T23:59:59.000Z

    A compressed full-text self-index occupies space close to that of the compressed text and simultaneously allows fast pattern matching and random access to the underlying text. Among the best compressed self-indexes, in theory and in practice, are several members of the FM-index family. In this paper, we describe new FM-index variants that combine nice theoretical properties, simple implementation and improved practical performance. Our main result is a new technique called fixed block compression boosting, which is a simpler and faster alternative to optimal compression boosting and implicit compression boosting used in previous FM-indexes.

  16. Performances of Multi-Level and Multi-Component Compressed Bitmap Indices

    E-Print Network [OSTI]

    Wu, Kesheng; Stockinger, Kurt; Shoshani, Arie

    2007-01-01T23:59:59.000Z

    Without compression, the index sizes monotonically decreaseprocessing cost. With compression, the index sizes no longermulti-component indexes without compression. Let C 1 , C

  17. Improving Energy Efficiency of Compressed Air System Based on System Audit

    E-Print Network [OSTI]

    Shanghai, Hongbo Qin; McKane, Aimee

    2008-01-01T23:59:59.000Z

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

  18. Alternative Fuel Vehicles: The Case of Compressed Natural Gas (CNG) Vehicles in California Households

    E-Print Network [OSTI]

    Abbanat, Brian A.

    2001-01-01T23:59:59.000Z

    VEHICLES: THE CASE OF COMPRESSED NATURAL GAS (CNG) VEHICLESyou first learn about compressed natural gas (CNG) vehicles?VEHICLES: THE CASE OF COMPRESSED NATURAL GAS (CNG) VEHICLES

  19. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    SciTech Connect (OSTI)

    Neil Todreas; Pavel Hejzlar

    2008-06-30T23:59:59.000Z

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  20. Compressed Air Systems Audits - Why? And How?

    E-Print Network [OSTI]

    Kemp, H. L.

    2004-01-01T23:59:59.000Z

    . Secondly, join us in the definition of compressed air as a system, the totality of which is comprised of the Supply Side and the Demand Side. The Supply Side is the compressors and their controls, receivers (primary storage tanks), aftercoolers, filters... and dryers, and ends at the Compressor Room door. The Demand side is all of the distribution piping system, and all of the end uses of the compressed air, including leaks The function of the audit (be it walk-through, assessment or full audit...

  1. Understanding the Basics of Compressed Air Systems

    E-Print Network [OSTI]

    Herron, D. J.

    compressed air loss to 5% of total compressed air generated. POTENTIAL SAVINGS CALCULATION Calculation to determine potential savings: % wasted hp x connected hp x .746 (kWhlM1p) x S/kWh x .90(system efficiency 8000 (operating hours/yr) $/yr...(potential savings) Example: (10 (wasted hpl x 750 hp x .746 x $.05 x 8000 = S24,867/yr .90 Calculation to determine full load cost: bhp x .746 x S/kWh x opt:rating hours motor eff. 3M Company St. Paul, MN Example: (500 cfm, 125 bhp, S.05/kWh, 8000...

  2. Fast electron microscopy via compressive sensing

    DOE Patents [OSTI]

    Larson, Kurt W; Anderson, Hyrum S; Wheeler, Jason W

    2014-12-09T23:59:59.000Z

    Various technologies described herein pertain to compressive sensing electron microscopy. A compressive sensing electron microscope includes a multi-beam generator and a detector. The multi-beam generator emits a sequence of electron patterns over time. Each of the electron patterns can include a plurality of electron beams, where the plurality of electron beams is configured to impart a spatially varying electron density on a sample. Further, the spatially varying electron density varies between each of the electron patterns in the sequence. Moreover, the detector collects signals respectively corresponding to interactions between the sample and each of the electron patterns in the sequence.

  3. Compressed Air Systems | Department of Energy

    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 33 1112011AT&T, Inc.'sEnergyTexas1.Space DataEnergyCompressed Air Systems Compressed Air

  4. Compressive auto-indexing in femtosecond nanocrystallography

    E-Print Network [OSTI]

    Maia, F R N C; Marchesini, S; 10.1016/j.ultramic.2010.10.016

    2010-01-01T23:59:59.000Z

    Ultrafast nanocrystallography has the potential to revolutionize biology by enabling structural elucidation of proteins for which it is possible to grow crystals with 10 or fewer unit cells on the side. The success of nanocrystallography depends on robust orientation-determination procedures that allow us to average diffraction data from multiple nanocrystals to produce a three dimensional (3D) diffraction data volume with a high signal-to-noise ratio. Such a 3D diffraction volume can then be phased using standard crystallographic techniques. "Indexing" algorithms used in crystallography enable orientation determination of diffraction data from a single crystal when a relatively large number of reflections are recorded. Here we show that it is possible to obtain the exact lattice geometry from a smaller number of measurements than standard approaches using a basis pursuit solver.

  5. Anisotropic Characterization of Asphalt Mixtures in Compression 

    E-Print Network [OSTI]

    Zhang, Yuqing 1983-

    2012-10-08T23:59:59.000Z

    and physically related to anisotropic modulus ratio. The anisotropic viscoelasticity was represented by complex moduli and Poisson's ratios in separate orthogonal directions that were determined by an efficient testing protocol. Master curve models were proposed...

  6. Radiological Follow-up of New Compression Fractures Following Percutaneous Vertebroplasty

    SciTech Connect (OSTI)

    Tanigawa, Noboru, E-mail: tanigano@takii.kmu.ac.jp; Komemushi, Atsushi; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Sawada, Satoshi [Kansai Medical University, Department of Radiology (Japan)

    2006-02-15T23:59:59.000Z

    The purpose of the present study was to ascertain chronological changes in the analgesic effects of percutaneous vertebroplasty (PVP) on osteoporotic vertebral compression factures and to radiologically follow new compression fractures after PVP. Seventy-six patients (206 vertebral bodies) were followed radiologically for a mean of 11.5 months. A visual analog scale (VAS; 0-10) was used to assess pain severity, and frontal and lateral plain radiographs of the thoracic and lumbar vertebrae were taken 1-3 days and 1, 4, 10, and 22 months after PVP.The average VAS score was 7.2 {+-} 2.0 (mean pain score {+-} standard deviation) before PVP, 2.5 {+-} 2.3 at 1-3 days after PVP, 2.2 {+-} 2.3 at 1 month, 1.9 {+-} 2.2 at 4 months, 1.8 {+-} 2.4 at 10 months, and 1.0 {+-} 0.2 at 22 months. A new compression fracture was confirmed in 56 vertebral bodies in 28 patients (36.8%), affecting 38 adjacent vertebral bodies (67.8%), 17 nonadjacent vertebral bodies (30.4%), and 1 treated vertebral body (1.8%). A new compression fracture occurred within 1 week of PVP in 2 vertebral bodies (3.6%), between 1 week and 1 month after PVP in 22 (39.3%), between 1 and 3 months in 12 (21.4%), between 3 and 6 months in 12 (21.4%), and after more than 6 months in 8 (14.3%). PVP was highly effective in relieving the pain associated with osteoporosis-induced vertebral compression fractures, and this analgesia was long lasting. Radiological follow-up observation revealed new compression fractures in about one-third of patients. More than half of these new compression fractures occurred in adjacent vertebral bodies within 3 months of PVP.

  7. Fact Sheet: Isothermal Compressed Air Energy Storage (October...

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

    SustainX will demonstrate an isothermal compressed air energy storage (ICAES) system. The system captures the heat from compression in water and stores the captured heat until it...

  8. COLLOQUIUM: Compressed Air Energy Storage: The Bridge to Our...

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

    April 30, 2014, 4:00pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Compressed Air Energy Storage: The Bridge to Our Renewable Energy Future Mr. Al Cavallo Consultant Compressed...

  9. Massive-scale RDF Processing Using Compressed Bitmap Indexes

    E-Print Network [OSTI]

    Madduri, Kamesh

    2013-01-01T23:59:59.000Z

    offers enough compression that the worst-case index size iscompression method to further improve the bitmap indexes forcompression methods are designed to minimize the compressed size of the index.

  10. 2014 - LNG Export, Compressed Natural Gas (CNG), Re-Exports ...

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

    4 - LNG Export, Compressed Natural Gas (CNG), Re-Exports & Long Term Natural Gas Applications 2014 - LNG Export, Compressed Natural Gas (CNG), Re-Exports & Long Term Natural Gas...

  11. automated chest compression: Topics by E-print Network

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

    or compressibility when acquiring signals in a compressible signal into a small amount of data.Interestingly,this may be changing the way engineers think Wang, Hsin-Min 350...

  12. CO? compression for capture-enabled power systems

    E-Print Network [OSTI]

    Suri, Rajat

    2009-01-01T23:59:59.000Z

    The objective of this thesis is to evaluate a new carbon dioxide compression technology - shock compression - applied specifically to capture-enabled power plants. Global warming has increased public interest in carbon ...

  13. Compressing Social Networks The Minimum Logarithmic Arrangement Problem

    E-Print Network [OSTI]

    Safro, Ilya

    Compressing Social Networks The Minimum Logarithmic Arrangement Problem Chad Waters School Orderings Heuristic Conclusion Motivation Determine the extent to which social networks can be compressed adjacency queries. Social networks are not random graphs. Exhibit distinctive local properties

  14. Energy Efficiency in Compressed Air Systems

    E-Print Network [OSTI]

    Hingorani, A.; Pavlov, A.

    2010-01-01T23:59:59.000Z

    Energy use in compressed air systems accounts for typically 10% of the total industrial electricity consumption. It also accounts for close to 99% of the CO2 footprint of an air compressor and approximately 80% of the life cycle costs of a...

  15. Advanced Controls for Industrial Compressed Air Systems

    E-Print Network [OSTI]

    Vold, P.; Gabel, S.; Carmichael, L.; Curtner, K.; Cirillo, N. C. Jr.

    at a Goulds Pumps manufacturing plant in Seneca Falls, New York, and is currently undergoing field testing. The compressed air system will optimize the energy efficiency of the 7 compressor system (1,850hp) at Goulds, while reducing system pressure...

  16. Cryo-compressed Hydrogen Storage. Tobias Brunner

    E-Print Network [OSTI]

    distribution along highways and in remote areas. Gaseous hydrogen distribution via pipelines in onlyCryo-compressed Hydrogen Storage. Tobias Brunner February 15th, 2011, Washington D.C. BMW Hydrogen. Hydrogen Storage Workshop. BMW EfficientDynamics Less emissions. More driving pleasure. #12;BMW Hydrogen

  17. Compression of Antiproton Clouds for Antihydrogen Trapping

    E-Print Network [OSTI]

    G. B. Andresen; W. Bertsche; P. D. Bowe; C. C. Bray; E. Butler; C. L. Cesar; S. Chapman; M. Charlton; J. Fajans; M. C. Fujiwara; R. Funakoshi; D. R. Gill; J. S. Hangst; W. N. Hardy; R. S. Hayano; M. E. Hayden; R. Hydomako; M. J. Jenkins; L. V. Jorgensen; L. Kurchaninov; R. Lambo; N. Madsen; P. Nolan; K. Olchanski; A. Olin; A. Povilus; P. Pusa; F. Robicheaux; E. Sarid; S. Seif El Nasr; D. M. Silveira; J. W. Storey; R. I. Thompson; D. P. van der Werf; J. S. Wurtele; Y. Yamazaki

    2008-06-30T23:59:59.000Z

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report the first detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile and its relation to that of the electron plasma.

  18. Technical Notes Compressive Sensing and Reconstruction

    E-Print Network [OSTI]

    Huang, Xun

    . Introduction COMPRESSIVE sensing is a newly emerging signal-processing method [1,2] in information technologies. If some prior knowledge, such as an inherent model of the fluid process of interest, can be incorporated noise by interaction of fan and stator assembly [5,12]. This tonal frequency sound propagates through

  19. Distributed Compressed Sensing in Dynamic Networks

    E-Print Network [OSTI]

    Eldar, Yonina

    Distributed Compressed Sensing in Dynamic Networks Stacy Patterson Department of Computer Science theoretical results to develop a distributed version of IHT for dynamic networks. Evaluations show that our throughout the network, it is desirable to perform this recovery within the network in a distributed fashion

  20. Regression Cubes with Lossless Compression and Aggregation

    E-Print Network [OSTI]

    Pei, Jian

    , in addition to the traditional simple measures such as count and average. Such new measures will allow users space. In this paper, we propose a fundamentally new class of measures, compressible measures, in order. With years of research and development of data warehouse and OLAP technology [15], [7], [1], [34], a large

  1. Asynchronous Compressive Radar , Samuel Palermo1

    E-Print Network [OSTI]

    Palermo, Sam

    produces considerable static power during the charge accumulation stage. As both the mixer and integrator] for data compression. An employed random demodulator front-end, which consisting of a dedicated mixer and an integrator, implements CS front-end in [4]. In this architecture the mixer must operate at or above

  2. Georgia Tech Profiling Overconsolidation Ratio in

    E-Print Network [OSTI]

    Mayne, Paul W.

    Properties: M = 6 sin'/(3-sin') ' = effective stress friction angle Cc = compression index Cs = swelling index . 1 ­ Cs/Cc IR = G/su = Undrained Rigidity Index G = shear modulus su = undrained shear strength vovot I qM OCR #12;Georgia Tech Determine Undrained Rigidity Index = shear stress= shear stress ss

  3. Geometrical constraints on plasma couplers for Raman compression Z. Toroker,1

    E-Print Network [OSTI]

    homogeneous plasmas. However, for high-power, large-aperture experiments, the homogeneous region becomes in addition to the longitudinal compression, so a large laser spot size will be required to process more power of the pump pulse. Because the energy in the long pump pulse is transformed to energy in the much shorter

  4. The Micromechanics of Westerley Granite at Large Compressive Loads H. S. BHAT,1,2

    E-Print Network [OSTI]

    Rosakis, Ares J.

    The Micromechanics of Westerley Granite at Large Compressive Loads H. S. BHAT,1,2 C. G. SAMMIS,1 not produce the large negative curvature in the failure surface observed in Westerly granite at high confining failure in Westerly granite. Both the observed curvature in the failure surface and the nonlinear strain

  5. Detailed Analysis and Control Issues of Homogeneous Charge Compression Ignition (HCCI)

    SciTech Connect (OSTI)

    Aceves, Salvador M.; Flowers, Daniel L.; Martinez-Frias, Joel; Espinosa-Loza, Francisco; Dibble, Robert

    2002-08-25T23:59:59.000Z

    Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work.

  6. ablation-absorption ratio spectrometry: Topics by E-print Network

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

    isotopes 2 A gas chromatographypyrolysisisotope ratio mass spectrometry system for high-precision dD measurements Environmental Sciences and Ecology Websites Summary: of...

  7. Mass dependence of balance energy for different N/Z ratio

    E-Print Network [OSTI]

    Aman D. Sood

    2011-09-28T23:59:59.000Z

    We present the study for the mass dependence of E$_{bal}$ for various N/Z ratios covering pure symmetric systems to highly neutron-rich ones.

  8. Compression of solid CO/sub 2/ at 296 K to 10 GPa

    SciTech Connect (OSTI)

    Olinger, B.

    1982-12-15T23:59:59.000Z

    The volume of solid CO/sub 2/ was measured at 296 K from 1 to 10 GPa using a high pressure, x-ray diffraction technique. The compression of NaF was used as the pressure gauge. The data are converted to the velocity plane and linearly fit. The volumes and bulk moduli are calculated from the fit as a function of pressure. Previous compression studies are discussed and a recent a priori calculation is shown to agree well with the present data.

  9. Large Photocathode Photodetectors Using Photon Amplification and Phase-Space Compression

    E-Print Network [OSTI]

    Carrio, Alex; Greener, Kevin; McGuiness, Sean; Podrasky, Victor; Sullivan, John; Winn, David R; Bilki, Burak; Onel, Yasar

    2014-01-01T23:59:59.000Z

    We describe a simple technique to both amplify incident photons and compress their angular x area phase space. These Optical Compressor Amplifier Tubes (OCA Tube) use techniques analogous to image intensifiers, using vacuum photocathodes to detect photons as converted to photoelectrons, amplify the photons via photoelectron bombardment of fast scintillators, and compress the optical phase space onto optical fibers, so that small, high gain photodetectors, like miniature PMT or SiPM, can be used to detect photons from large areas, at comparatively low cost. The properties of and benefits of OCA tubes are described.

  10. Novel Spark Plugs Improve Energy Efficiency of Compressed Natural

    E-Print Network [OSTI]

    Novel Spark Plugs Improve Energy Efficiency of Compressed Natural Gas Engines Energy Innovations use affects climate change. Vehicles operating on compressed natural gas reduce petroleum fuel use, the vast majority of compressed natural gas (CNG) engines are used in transit buses serving the public

  11. Technical assessment of compressed hydrogen storage tank systems for automotive applications.

    SciTech Connect (OSTI)

    Hua, T. Q.; Ahluwalia, R. K.; Peng, J. K.; Kromer, M.; Lasher, S.; McKenney, K.; Law, K.; Sinha, J. (Nuclear Engineering Division); (TIAX, LLC)

    2011-02-09T23:59:59.000Z

    The performance and cost of compressed hydrogen storage tank systems has been assessed and compared to the U.S. Department of Energy (DOE) 2010, 2015, and ultimate targets for automotive applications. The on-board performance and high-volume manufacturing cost were determined for compressed hydrogen tanks with design pressures of 350 bar ({approx}5000 psi) and 700 bar ({approx}10,000 psi) capable of storing 5.6 kg of usable hydrogen. The off-board performance and cost of delivering compressed hydrogen was determined for hydrogen produced by central steam methane reforming (SMR). The main conclusions of the assessment are that the 350-bar compressed storage system has the potential to meet the 2010 and 2015 targets for system gravimetric capacity but will not likely meet any of the system targets for volumetric capacity or cost, given our base case assumptions. The 700-bar compressed storage system has the potential to meet only the 2010 target for system gravimetric capacity and is not likely to meet any of the system targets for volumetric capacity or cost, despite the fact that its volumetric capacity is much higher than that of the 350-bar system. Both the 350-bar and 700-bar systems come close to meeting the Well-to-Tank (WTT) efficiency target, but fall short by about 5%. These results are summarized.

  12. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    E-Print Network [OSTI]

    Rutqvist, J.

    2013-01-01T23:59:59.000Z

    compressed air energy storage technology by the hydraulicscale electric energy storage technologies. Compressed air

  13. Application of Compressed Sensing to 2-D Ultrasonic Propagation Imaging System data

    SciTech Connect (OSTI)

    Mascarenas, David D. [Los Alamos National Laboratory; Farrar, Charles R. [Los Alamos National Laboratory; Chong, See Yenn [Engineering Institute-Korea; Lee, J.R. [Engineering Institute-Korea; Park, Gyu Hae [Los Alamos National Laboratory; Flynn, Eric B. [Los Alamos National Laboratory

    2012-06-29T23:59:59.000Z

    The Ultrasonic Propagation Imaging (UPI) System is a unique, non-contact, laser-based ultrasonic excitation and measurement system developed for structural health monitoring applications. The UPI system imparts laser-induced ultrasonic excitations at user-defined locations on a structure of interest. The response of these excitations is then measured by piezoelectric transducers. By using appropriate data reconstruction techniques, a time-evolving image of the response can be generated. A representative measurement of a plate might contain 800x800 spatial data measurement locations and each measurement location might be sampled at 500 instances in time. The result is a total of 640,000 measurement locations and 320,000,000 unique measurements. This is clearly a very large set of data to collect, store in memory and process. The value of these ultrasonic response images for structural health monitoring applications makes tackling these challenges worthwhile. Recently compressed sensing has presented itself as a candidate solution for directly collecting relevant information from sparse, high-dimensional measurements. The main idea behind compressed sensing is that by directly collecting a relatively small number of coefficients it is possible to reconstruct the original measurement. The coefficients are obtained from linear combinations of (what would have been the original direct) measurements. Often compressed sensing research is simulated by generating compressed coefficients from conventionally collected measurements. The simulation approach is necessary because the direct collection of compressed coefficients often requires compressed sensing analog front-ends that are currently not commercially available. The ability of the UPI system to make measurements at user-defined locations presents a unique capability on which compressed measurement techniques may be directly applied. The application of compressed sensing techniques on this data holds the potential to reduce the number of required measurement locations, reduce the time to make measurements, reduce the memory required to store the measurements, and possibly reduce the computational burden to classify the measurements. This work considers the appropriate selection of the signal dictionary used for signal reconstruction, and performs an evaluation of compressed sensing technique's ability to reconstruct ultrasonic images using fewer measurements than would be needed using traditional Nyquist-limited data collection techniques.

  14. Increasing the transformer ratio at the Argonne wakefield accelerator.

    SciTech Connect (OSTI)

    Power, J.G.; Conde, M.; Liu, W.; Yusof, Z.; Gai, W.; Jing, C.; Kanareykin, A. (High Energy Physics); (Euclid Techlabs, LLC)

    2011-01-01T23:59:59.000Z

    The transformer ratio is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss experienced by the drive bunch (or a bunch within a multidrive bunch train). This plays an important role in the collinear wakefield acceleration scheme. A high transformer ratio is desirable since it leads to a higher overall efficiency under similar conditions (e.g. the same beam loading, the same structure, etc.). One technique to enhance the transformer ratio beyond the ordinary limit of 2 is to use a ramped bunch train. The first experimental demonstration observed a transformer ratio only marginally above 2 due to the mismatch between the drive microbunch length and the frequency of the accelerating structure [C. Jing, A. Kanareykin, J. Power, M. Conde, Z. Yusof, P. Schoessow, and W. Gai, Phys. Rev. Lett. 98, 144801 (2007)]. Recently, we revisited this experiment with an optimized microbunch length using a UV laser stacking technique at the Argonne Wakefield Accelerator facility and measured a transformer ratio of 3.4. Measurements and data analysis from these experiments are presented in detail.

  15. Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields

    SciTech Connect (OSTI)

    Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2013-07-15T23:59:59.000Z

    We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ?50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.

  16. Revealing Compressed Stops Using High-Momentum Recoils

    E-Print Network [OSTI]

    Macaluso, Sebastian; Shih, David; Tweedie, Brock

    2015-01-01T23:59:59.000Z

    Searches for supersymmetric top quarks at the LHC have been making great progress in pushing sensitivity out to higher mass, but are famously plagued by gaps in coverage around lower-mass regions where the decay phase space is closing off. Within the common stop-NLSP / neutralino-LSP simplified model, the line in the mass plane where there is just enough phase space to produce an on-shell top quark remains almost completely unconstrained. Here, we show that is possible to define searches capable of probing a large patch of this difficult region, with S/B ~ 1 and significances often well beyond 5 sigma. The basic strategy is to leverage the large energy gain of LHC Run 2, leading to a sizable population of stop pair events recoiling against a hard jet. The recoil not only re-establishes a MET signature, but also leads to a distinctive anti-correlation between the MET and the recoil jet transverse vectors when the stops decay all-hadronically. Accounting for jet combinatorics, backgrounds, and imperfections in ...

  17. Gipfeli -High Speed Compression Algorithm Rastislav LenhardtI, II

    E-Print Network [OSTI]

    Cortes, Corinna

    sliding window, based on 1977 paper by Lempel and Ziv, enriched with an ad-hoc entropy coding for both in CPU performance. This puts other parts of the system under pressure and often makes I/O operations sliding window. This has already been suggested in the previous work of Williams [6], Fiala and Greene [7

  18. Optimal Filters for High-Speed Compressive Detection in ...

    E-Print Network [OSTI]

    2013-02-14T23:59:59.000Z

    ... medicine and biology, pharmacy, counterfeit detection, and national security. ... full spectral information, multivariate statistical techniques can be employed to ...

  19. High Fidelity Modeling of Premixed Charge Compression Ignition...

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

    chemical kinetics into KIVA3V for fast analysis of HCCI combustion and emissions (KIVA3V-ANN) 6 Option:UCRL Option:Additional Information Lawrence Livermore National Laboratory 1...

  20. Optimal Filters for High-Speed Compressive Detection in ...

    E-Print Network [OSTI]

    2013-02-14T23:59:59.000Z

    Feb 28, 2013 ... this to give an algorithm to design optimal filters to minimize the mean squared error ... Rapid identification and quantification of chemical species in complex mixtures is ..... model,” Optical Engineering 49(11), 113601 (2010).

  1. High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion

    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), GeothermalGridHYDROGEN TOTechnology ValidationCombustionTechnologies|

  2. High-Efficiency Clean Combustion Design for Compression Ignition Engines |

    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 p p a a r r t t m m e1Department

  3. High-Efficiency Clean Combustion Engine Designs for Compression Ignition

    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 p p a a r r t t m m e1DepartmentEngines

  4. Advanced CFD Models for High Efficiency Compression Ignition Engines |

    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 Your Destiny: The Future of1 AAccelerated agingDepartment of Energy 1

  5. arXiv:cond-mat/0305430v119May2003 Shearing or Compressing a Soft Glass in 2D: Time-concentration superposition

    E-Print Network [OSTI]

    Cicuta, Pietro

    arXiv:cond-mat/0305430v119May2003 Shearing or Compressing a Soft Glass in 2D: Time dimensional monolayers should be regarded as being close to a soft glass state. PACS numbers: 68.18.-g, 83.60.bc The rheology of systems with very large surface to vol- ume ratios, such as foams or emulsions

  6. Compression mode resonances in Zr-90

    E-Print Network [OSTI]

    Youngblood, David H.; Lui, YW; John, B.; Tokimoto, Y.; Clark, HL; Chen, X.

    2004-01-01T23:59:59.000Z

    Compression mode resonances in 90Zr D. H. Youngblood, Y.-W. Lui, B. John,* Y. Tokimoto, H. L. Clark, and X. Chen Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA (Received 18 February 2004; published 20 May 2004..., JOHN, TOKIMOTO, CLARK, AND CHEN PHYSICAL REVIEW C 69, 054312 (2004) 054312-2 Fig. 2. The continuum distributions are similar over the en- tire energy range, whereas the angular distributions of the cross sections for the peak change...

  7. Compression of ground-motion data

    SciTech Connect (OSTI)

    Long, J.W.

    1981-04-01T23:59:59.000Z

    Ground motion data has been recorded for many years at Nevada Test Site and is now stored on thousands of digital tapes. The recording format is very inefficient in terms of space on tape. This report outlines a method to compress the data onto a few hundred tapes while maintaining the accuracy of the recording and allowing restoration of any file to the original format for future use. For future digitizing a more efficient format is described and suggested.

  8. Electrochemical Hydrogen Compression (EHC) | 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 Your Destiny:RevisedAdvisory BoardNucleateElectrochemical Hydrogen Compression (EHC)

  9. High constriction ratio continuous insulator based dielectrophoretic particle sorting

    E-Print Network [OSTI]

    Wang, Qianru, S.M. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    Low frequency insulator based dielectrophoresis (iDEP) is a promising technique to study cell surface dielectric properties. To date, iDEP has been exploited to distinguish, characterize, and manipulate particles and ...

  10. Air flow in a high aspect ratio heat sink

    E-Print Network [OSTI]

    Allison, Jonathan Michael

    2010-01-01T23:59:59.000Z

    The increasing heat output of modern electronics requires concomitant advances in heat sinking technology: reductions in thermal resistance and required pumping power are necessary. This research covers the development of ...

  11. Negative Resists for Ultra-Tall, High Aspect Ratio Microstructures

    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 for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparency VisitSilver Toyota1ResourceloadingOurAlamosNedResists for

  12. High Aspect Ratio Metallic Structures for Use as Transparent Electrodes -

    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 for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment ofHeatHenryDuncanC.-Y.J.InnovationEnergy

  13. High Aspect Ratio Metallic Structures for Use as Transparent Electrodes -

    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 for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment

  14. Low loss hollow optical-waveguide connection from atmospheric pressure to ultra-high vacuum

    SciTech Connect (OSTI)

    Ermolov, A.; Mak, K. F.; Tani, F.; Hölzer, P.; Travers, J. C. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)] [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Russell, P. St. J. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany) [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Department of Physics, University of Erlangen-Nuremberg, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)

    2013-12-23T23:59:59.000Z

    A technique for optically accessing ultra-high vacuum environments, via a photonic-crystal fiber with a long small hollow core, is described. The small core and the long bore enable a pressure ratio of over 10{sup 8} to be maintained between two environments, while permitting efficient and unimpeded delivery of light, including ultrashort optical pulses. This delivery can be either passive or can encompass nonlinear optical processes such as optical pulse compression, deep UV generation, supercontinuum generation, or other useful phenomena.

  15. Combined rankine and vapor compression cycles

    DOE Patents [OSTI]

    Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

    2005-04-19T23:59:59.000Z

    An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

  16. Abundance Ratios in Early-Type Galaxies

    E-Print Network [OSTI]

    Reynier Peletier

    1999-04-21T23:59:59.000Z

    Although evidence is accumulating that abundance ratios in galaxies are often non-solar, they are far from understood. I resume the current evidence for non-solar abundance ratios, supplementing the recent review by Worthey (1998) with some new results. It appears that the Mg/Fe abundance ratio only depends on the mass of the galaxy, not on the formation time-scale. For massive galaxies [Mg/Fe] > 0, while small galaxies show solar abundance ratios. Information about abundances of other element is scarce, but new evidence is given that [Ca/Fe] is solar, or slightly lower than solar, contrary to what is expected for an alpha-element.

  17. Pair distribution function study on compression of liquid gallium

    SciTech Connect (OSTI)

    Luo, Shengnian [Los Alamos National Laboratory; Yu, Tony [SUNY-SB; Chen, Jiuhua [SUNY-SB; Ehm, Lars [SUNY-SB; Guo, Quanzhong [SUNY-SB; Parise, John [SUNY-SB

    2008-01-01T23:59:59.000Z

    Integrating a hydrothermal diamond anvil cell (HDAC) and focused high energy x-ray beam from the superconductor wiggler X17 beamline at the National Synchrotron Light Source (NSLS) at the Brookhaven National Laboratory (BNL), we have successfully collected high quality total x-ray scattering data of liquid gallium. The experiments were conducted at a pressure range from 0.1GPa up to 2GPa at ambient temperature. For the first time, pair distribution functions (PDF) for liquid gallium at high pressure were derived up to 10 {angstrom}. Liquid gallium structure has been studied by x-ray absorption (Di Cicco & Filipponi, 1993; Wei et al., 2000; Comez et al., 2001), x-ray diffraction studies (Waseda & Suzuki, 1972), and molecular dynamics simulation (Tsay, 1993; Hui et al., 2002). These previous reports have focused on the 1st nearest neighbor structure, which tells us little about the atomic arrangement outside the first shell in non- crystalline materials. This study focuses on the structure of liquid gallium and the atomic structure change due to compression. The PDF results show that the observed atomic distance of the first nearest neighbor at 2.78 {angstrom} (first G(r) peak and its shoulder at the higher Q position) is consistent with previous studies by x-ray absorption (2.76 {angstrom}, Comez et al., 2001). We have also observed that the first nearest neighbor peak position did not change with pressure increasing, while the farther peaks positions in the intermediate distance range decreased with pressure increasing. This leads to a conclusion of the possible existence of 'locally rigid units' in the liquid. With the addition of reverse Monte Carlo modeling, we have observed that the coordination number in the local rigit unit increases with pressure. The bulk modulus of liquid gallium derived from the volume compression curve at ambient temperature (300K) is 12.1(6) GPa.

  18. Seneca Compressed Air Energy Storage (CAES) Project

    SciTech Connect (OSTI)

    None

    2012-11-30T23:59:59.000Z

    Compressed Air Energy Storage (CAES) is a hybrid energy storage and generation concept that has many potential benefits especially in a location with increasing percentages of intermittent wind energy generation. The objectives of the NYSEG Seneca CAES Project included: for Phase 1, development of a Front End Engineering Design for a 130MW to 210 MW utility-owned facility including capital costs; project financials based on the engineering design and forecasts of energy market revenues; design of the salt cavern to be used for air storage; draft environmental permit filings; and draft NYISO interconnection filing; for Phase 2, objectives included plant construction with a target in-service date of mid-2016; and for Phase 3, objectives included commercial demonstration, testing, and two-years of performance reporting. This Final Report is presented now at the end of Phase 1 because NYSEG has concluded that the economics of the project are not favorable for development in the current economic environment in New York State. The proposed site is located in NYSEG’s service territory in the Town of Reading, New York, at the southern end of Seneca Lake, in New York State’s Finger Lakes region. The landowner of the proposed site is Inergy, a company that owns the salt solution mining facility at this property. Inergy would have developed a new air storage cavern facility to be designed for NYSEG specifically for the Seneca CAES project. A large volume, natural gas storage facility owned and operated by Inergy is also located near this site and would have provided a source of high pressure pipeline quality natural gas for use in the CAES plant. The site has an electrical take-away capability of 210 MW via two NYSEG 115 kV circuits located approximately one half mile from the plant site. Cooling tower make-up water would have been supplied from Seneca Lake. NYSEG’s engineering consultant WorleyParsons Group thoroughly evaluated three CAES designs and concluded that any of the designs would perform acceptably. Their general scope of work included development of detailed project construction schedules, capital cost and cash flow estimates for both CAES cycles, and development of detailed operational data, including fuel and compression energy requirements, to support dispatch modeling for the CAES cycles. The Dispatch Modeling Consultant selected for this project was Customized Energy Solutions (CES). Their general scope of work included development of wholesale electric and gas market price forecasts and development of a dispatch model specific to CAES technologies. Parsons Brinkerhoff Energy Storage Services (PBESS) was retained to develop an air storage cavern and well system design for the CAES project. Their general scope of work included development of a cavern design, solution mining plan, and air production well design, cost, and schedule estimates for the project. Detailed Front End Engineering Design (FEED) during Phase 1 of the project determined that CAES plant capital equipment costs were much greater than the $125.6- million originally estimated by EPRI for the project. The initial air storage cavern Design Basis was increased from a single five million cubic foot capacity cavern to three, five million cubic foot caverns with associated air production wells and piping. The result of this change in storage cavern Design Basis increased project capital costs significantly. In addition, the development time required to complete the three cavern system was estimated at approximately six years. This meant that the CAES plant would initially go into service with only one third of the required storage capacity and would not achieve full capability until after approximately five years of commercial operation. The market price forecasting and dispatch modeling completed by CES indicated that the CAES technologies would operate at only 10 to 20% capacity factors and the resulting overall project economics were not favorable for further development. As a result of all of these factors, the Phase 1 FEED developed an installe

  19. Development of Enabling Technologies for High Efficiency, Low...

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

    Advanced Combustion in Improving Thermal Efficiency Development of Enabling Technologies for High Efficiency, Low Emissions Homogeneous Charge Compression Ignition (HCCI) Engines...

  20. DEVELOPMENT OF A HIGH PERFORMANCE COLD CLIMATE HEAT PUMP

    SciTech Connect (OSTI)

    Horton, W. Travis [Purdue University] [Purdue University; Groll, Eckhard A. [Purdue University] [Purdue University; Braun, James E. [Purdue University] [Purdue University

    2014-06-01T23:59:59.000Z

    The primary goals of the proposed project were to develop, test, and evaluate a high performance and cost-effective vapor compression air-source heat pump for use in cold climate regions. Vapor compression heat pumps are a proven technology, and have been used for many years to meet heating requirements for buildings in residential, commercial, and industrial applications. However, in climate regions that experience very low outdoor ambient temperatures both the heating capacity and coefficient of performance (COP) of traditional air-source vapor compression heat pumps drops dramatically with a decrease in the outdoor air temperature. The efficiency of heat pumping equipment has improved substantially over the past 20 years; however, the efficiencies of the highest rated equipment on the market are approaching practical limits that cannot be surpassed without modifications to the basic cycle and possibly the use of additional hardware. In this report, three technologies to improve the efficiency of vapor compression systems are described. These are a) vapor injected compression, b) oil flooded compression and c) hybrid flow control of the evaporator. Compressor prototypes for both, oil flooded and vapor injected compression were developed by Emerson Climate Technologies. For the oil flooded compressor, the oil injection port location was optimized and an internal oil separator was added using several design iterations. After initial testing at Emerson Climate Technologies, further testing was done at Purdue University, and compressor models were developed. These models were then integrated into a system model to determine the achievable improvement of seasonal energy efficiency (SEER) for Minneapolis (Minnesota) climate. For the oil flooded compression, a 34% improvement in seasonal energy efficiency was found while a 21% improvement in seasonal energy efficiency ratio was found for the vapor injected compression. It was found that one benefit of both tested compression technologies is a lower discharge temperature, which allows for continued operation at lower ambient temperatures. A bin analysis of the vapor injected prototype cold climate heat pump predicts a 6% improvement in HSPF for Minneapolis. This improvement is mainly a result of the increased capacity of the system for active vapor injection. For the oil flooded system, a slightly larger performance improvement is predicted, in this case mostly caused by an increase in heating COP. Based on an economic analysis of these results, the maximum additional cost of the system changes, for the Minneapolis location, are $430 for the vapor injected system and $391 for the oil flooded system. These estimates assume that a 3-year simple payback period is accepted by the customer. For the hybrid flow control of evaporators, a new type of balancing valve was developed together with Emerson Climate technologies to reduce the cost of the control scheme. In contrast to conventional stepper motor valves, this valve requires less cables and can be driven by a cheaper output circuit on the control board. The correct valve size was determined in a dedicated test stand in several design iterations. The performance benefits of the hybrid control of the evaporator coil were determined for clean coil conditions as well as with partial blockage of the air inlet grille and under frosting conditions. For clean coil conditions, the benefits in terms of COP and capacity are negligible. However, significant benefits were noted for severely air-maldistributed operating conditions. For the H2-test, the maximum COP improvement of 17% along with a capacity improvement of nearly 40% was observed. Overall, the hybrid control scheme leads to a significant amount of performance improvement, if the air inlet conditions to the evaporator are maldistributed.

  1. Ratio model serves suprathreshold color luminance discrimination

    E-Print Network [OSTI]

    Mullen, Kathy T.

    Ratio model serves suprathreshold color­ luminance discrimination Marcel J. Sankeralli and Kathy T quadrants of the red­ green/luminance and blue­yellow/luminance planes of cardinal color space. We showed model of suprathreshold color­luminance dis- crimination, in which discrimination depends on a ratio

  2. DAMPE silicon tracker on-board data compression algorithm

    E-Print Network [OSTI]

    Dong, Yifan; Qiao, Rui; Peng, Wenxi; Fan, Ruirui; Gong, Ke; Wu, Di; Wang, Huanyu

    2015-01-01T23:59:59.000Z

    The Dark Matter Particle Explorer (DAMPE) is an upcoming scientific satellite mission for high energy gamma-ray, electron and cosmic rays detection. The silicon tracker (STK) is a sub detector of the DAMPE payload with an excellent position resolution (readout pitch of 242um), which measures the incident direction of particles, as well as charge. The STK consists 12 layers of Silicon Micro-strip Detector (SMD), equivalent to a total silicon area of 6.5m$^2$. The total readout channels of the STK are 73728, which leads to a huge amount of raw data to be dealt. In this paper, we focus on the on-board data compression algorithm and procedure in the STK, which was initially verified by cosmic-ray measurements.

  3. Percutaneous Vertebroplasty for Osteoporotic Compression Fracture: Multivariate Study of Predictors of New Vertebral Body Fracture

    SciTech Connect (OSTI)

    Komemushi, Atsushi, E-mail: kome64@yo.rim.or.jp; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo [Kansai Medical University, Department of Radiology (Japan); Komemushi, Sadao [Kinki University, Schoool of Agriculture (Japan); Sawada, Satoshi [Kansai Medical University, Department of Radiology (Japan)

    2006-08-15T23:59:59.000Z

    Purpose. To investigate the risk factors and relative risk of new compression fractures following vertebroplasty. Methods. Initially, we enrolled 104 consecutive patients with vertebral compression fractures caused by osteoporosis. A total of 83 of the 104 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty. Logistic regression analysis of the data obtained from these 83 patients was used to determine relative risks of recurrent compression fractures, using 13 different factors. Results. We identified 59 new fractures in 30 of the 83 patients: 41 new fractures in vertebrae adjacent to treated vertebrae; and 18 new fractures in vertebrae not adjacent to treated vertebrae. New fractures occurred in vertebrae adjacent to treated vertebrae significantly more frequently than in vertebrae not adjacent to treated vertebrae. Only cement leakage into the disk was a significant predictor of new vertebral body fracture after vertebroplasty (odds ratio = 4.633). None of the following covariates were associated with increased risk of new fracture: age, gender, bone mineral density, the number of vertebroplasty procedures, the number of vertebrae treated per procedure, the cumulative number of vertebrae treated, the presence of a single untreated vertebra between treated vertebrae, the presence of multiple untreated vertebrae between treated vertebrae, the amount of bone cement injected per procedure, the cumulative amount of bone cement injected, cement leakage into the soft tissue around the vertebra, and cement leakage into the vein.

  4. Low emissions compression ignited engine technology

    DOE Patents [OSTI]

    Coleman, Gerald N. (Dunlap, IL); Kilkenny, Jonathan P. (Peoria, IL); Fluga, Eric C. (Dunlap, IL); Duffy, Kevin P. (East Peoria, IL)

    2007-04-03T23:59:59.000Z

    A method and apparatus for operating a compression ignition engine having a cylinder wall, a piston, and a head defining a combustion chamber. The method and apparatus includes delivering fuel substantially uniformly into the combustion chamber, the fuel being dispersed throughout the combustion chamber and spaced from the cylinder wall, delivering an oxidant into the combustion chamber sufficient to support combustion at a first predetermined combustion duration, and delivering a diluent into the combustion chamber sufficient to change the first predetermined combustion duration to a second predetermined combustion duration different from the first predetermined combustion duration.

  5. CO2 Compression | netl.doe.gov

    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 Siteandscience, and8Critical4CO2 Compression CO2

  6. Minimize Compressed Air Leaks | 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 Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOil &315_ArnibanPriority DataPART 970MidwestChallengeCompressed Air

  7. Compressible Turbulence in Galaxy Clusters: Physics and Stochastic Particle Re-acceleration

    E-Print Network [OSTI]

    G. Brunetti; A. Lazarian

    2007-03-22T23:59:59.000Z

    We attempt to explain the non-thermal emission arising from galaxy clusters as a result of the re-acceleration of electrons by compressible turbulence induced by cluster mergers. In our model intracluster medium (ICM) is represented by a high beta plasma in which turbulent motions are driven at large scales. The corresponding injection velocities are higher than the Alfven velocity. As a result, the turbulence is approximately isotropic up to the scale at which the turbulent velocity gets comparable with the Alfven velocity. Under the hypothesis that turbulence in the ICM is highly super- Alfvenic the magnetic field is passively advected and the field lines are bended on scales smaller than that of the classical, unmagnetized, ion-ion mean free path. This affects ion diffusion and the strength of the effective viscosity. Under these conditions the bulk of turbulence in hot (5-10 keV temperature) galaxy clusters is likely to be dissipated at collisionless scales via resonant coupling with thermal and fast particles. We use collisionless physics to derive the amplitude of the different components of the energy of the compressible modes, and review and extend the treatment of plasma damping in the ICM. We calculate the acceleration of both protons and electrons taking into account both TTD acceleration and non-resonant acceleration by large scale compressions. We find that relativistic electrons can be re-accelerated in the ICM up to energies of several GeV provided that the rms velocity of the compressible turbulent-eddies is (V_L/c_s)^2~0.15-0.3. We find that under typical conditions ~ 2-5 % of the energy flux of the cascading of compressible motions injected at large scales goes into the acceleration of fast particles and that this may explain the observed non-thermal emission from merging galaxy clusters.

  8. A New Compressive Imaging Camera Architecture using Optical-Domain Compression

    E-Print Network [OSTI]

    for processing, to a "computa- tional signal processing" (CSP) paradigm, where analog signals are converted nonlinear techniques. 1.1. Compressive sensing CSP builds upon a core tenet of signal processing a decorrelating transform to compact a correlated signal's energy into just a few essential coefficients.1

  9. artificial compressibility method: Topics by E-print Network

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

    solutions of the Incompressible Navier Stokes system on exterior domains via the artificial compressibility method Mathematical Physics (arXiv) Summary: In this paper we study...

  10. A Compressed Self-Index for Genomic Databases

    E-Print Network [OSTI]

    Gagie, Travis; Nekrich, Yakov; Puglisi, Simon J

    2011-01-01T23:59:59.000Z

    Advances in DNA sequencing technology will soon result in databases of thousands of genomes. Within a species, individuals' genomes are almost exact copies of each other; e.g., any two human genomes are 99.9% the same. Relative Lempel-Ziv (RLZ) compression takes advantage of this property: it stores the first genome uncompressed or as an FM-index, then compresses the other genomes with a variant of LZ77 that copies phrases only from the first genome. RLZ achieves good compression and supports fast random access; in this paper we show how to support fast search as well, thus obtaining an efficient compressed self-index.

  11. COMPRESSIVE SAMPLING VS. CONVENTIONAL IMAGING Jarvis Haupt and Robert Nowak

    E-Print Network [OSTI]

    Haupt, Jarvis

    COMPRESSIVE SAMPLING VS. CONVENTIONAL IMAGING Jarvis Haupt and Robert Nowak University of Wisconsin from random projections than from pixel samples. However, the performance of CS can degrade markedly

  12. Saturable inductor and transformer structures for magnetic pulse compression

    DOE Patents [OSTI]

    Birx, Daniel L. (Londonderry, NH); Reginato, Louis L. (Orinda, CA)

    1990-01-01T23:59:59.000Z

    Saturable inductor and transformer for magnetic compression of an electronic pulse, using a continuous electrical conductor looped several times around a tightly packed core of saturable inductor material.

  13. Advancement in Fuel Spray and Combustion Modeling for Compression...

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

    Applications Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies...

  14. Investing in Our Energy Future: The Story of General Compression...

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

    General Compression February 29, 2012 - 9:23am Addthis April Saylor April Saylor Former Digital Outreach Strategist, Office of Public Affairs What does government funding mean to...

  15. NJ Compressed Natural Gas Refuse Trucks, Shuttle Buses and Infrastruct...

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

    Vehicle Technologies Program Review Presentation NJ COMPRESSED NATURAL GAS REFUSE TRUCKS, SHUTTLE BUSES AND INFRASTRUCTURE Chuck Feinberg, Principal Investigator New Jersey Clean...

  16. Workshop Notes from ""Compressed Natural Gas and Hydrogen Fuels...

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

    Workshop Notes from ""Compressed Natural Gas and Hydrogen Fuels: Lessons Learned for the Safe Deployment of Vehicles"" Workshop, December 10-11, 2009 Workshop Notes from...

  17. Rotary Vapor Compression Cycle Technology: A Pathway to Ultra...

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

    Cycle Technology: A Pathway to Ultra-Efficient Air Conditioning, Heating and Refrigeration Rotary Vapor Compression Cycle Technology: A Pathway to Ultra-Efficient Air...

  18. Experiment Hazard Class 5.4 - Compressed Gas Cylinders

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

    compressed flammable gas and pyrophoric gases. Consultation with EQO Industrial Hygiene when planning experiments that involve toxic gas, oxygen deficiency hazards or other...

  19. VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater

    E-Print Network [OSTI]

    Furht, Borko

    9 VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater Florida Atlantic University........................................................................................................................ 172 1.1 VIDEO REPRESENTATION AND FORMATS.................................................................................. 172 1.2 VIDEO INFORMATION UNITS

  20. Technical Assessment: Cryo-Compressed Hydrogen Storage for Vehicular...

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

    with input from Salvador Aceves (Lawrence Livermore National Lab) and Tobias Brunner (BMW). Technical Assessment: Cryo-Compressed Hydrogen Storage for Vehicular Applications...

  1. University of Arizona Compressed Air Energy Storage

    SciTech Connect (OSTI)

    Simmons, Joseph; Muralidharan, Krishna

    2012-12-31T23:59:59.000Z

    Boiled down to its essentials, the grant’s purpose was to develop and demonstrate the viability of compressed air energy storage (CAES) for use in renewable energy development. While everyone agrees that energy storage is the key component to enable widespread adoption of renewable energy sources, the development of a viable scalable technology has been missing. The Department of Energy has focused on expanded battery research and improved forecasting, and the utilities have deployed renewable energy resources only to the extent of satisfying Renewable Portfolio Standards. The lack of dispatchability of solar and wind-based electricity generation has drastically increased the cost of operation with these components. It is now clear that energy storage coupled with accurate solar and wind forecasting make up the only combination that can succeed in dispatchable renewable energy resources. Conventional batteries scale linearly in size, so the price becomes a barrier for large systems. Flow batteries scale sub-linearly and promise to be useful if their performance can be shown to provide sufficient support for solar and wind-base electricity generation resources. Compressed air energy storage provides the most desirable answer in terms of scalability and performance in all areas except efficiency. With the support of the DOE, Tucson Electric Power and Science Foundation Arizona, the Arizona Research Institute for Solar Energy (AzRISE) at the University of Arizona has had the opportunity to investigate CAES as a potential energy storage resource.

  2. Compact wavefunctions from compressed imaginary time evolution

    E-Print Network [OSTI]

    Jarrod R. McClean; Alán Aspuru-Guzik

    2014-09-25T23:59:59.000Z

    Simulation of quantum systems promises to deliver physical and chemical predictions for the frontiers of technology. Unfortunately, the exact representation of these systems is plagued by the exponential growth of dimension with the number of particles, or colloquially, the curse of dimensionality. The success of approximation methods has hinged on the relative simplicity of physical systems with respect to the exponentially complex worst case. Exploiting this relative simplicity has required detailed knowledge of the physical system under study. In this work, we introduce a general and efficient black box method for many-body quantum systems that utilizes technology from compressed sensing to find the most compact wavefunction possible without detailed knowledge of the system. It is a Multicomponent Adaptive Greedy Iterative Compression (MAGIC) scheme. No knowledge is assumed in the structure of the problem other than correct particle statistics. This method can be applied to many quantum systems such as spins, qubits, oscillators, or electronic systems. As an application, we use this technique to compute ground state electronic wavefunctions of hydrogen fluoride and recover 98% of the basis set correlation energy or equivalently 99.996% of the total energy with $50$ configurations out of a possible $10^7$. Building from this compactness, we introduce the idea of nuclear union configuration interaction for improving the description of reaction coordinates and use it to study the dissociation of hydrogen fluoride and the helium dimer.

  3. Compression station key to Texas pipeline project

    SciTech Connect (OSTI)

    NONE

    1996-10-01T23:59:59.000Z

    This was probably the largest pipeline project in the US last year, and the largest in Texas in the last decade. The new compressor station is a key element in this project. TECO, its servicing dealer, and compression packager worked closely throughout the planning and installation stages of the project. To handle the amount of gas required, TECO selected the GEMINI F604-1 compressor, a four-throw, single-stage unit with a six-inch stroke manufactured by Weatherford Enterra Compression Co. (WECC) in Corpus Christi, TX. TECO also chose WECC to package the compressors. Responsibility for ongoing support of the units will be shared among TECO, the service dealer and the packager. TECO is sending people to be trained by WECC, and because the G3600 family of engines is still relatively new, both the Caterpillar dealer and WECC sent people for advanced training at Caterpillar facilities in Peoria, IL. As part of its service commitment to TECO, the servicing dealer drew up a detailed product support plan, encompassing these five concerns: Training, tooling; parts support; service support; and commissioning.

  4. Gram-scale, high-yield synthesis of a robust metalorganic framework for storing methane and

    E-Print Network [OSTI]

    with compressed natural gas tanks (CNG) used in vehicles today, when the latter are pressurized to 248 bar (3600 The compressed natural gas (CNG) fuel tanks in current use need to be heavily reinforced, which increases, and compress natural gas to such high pressures requires signi- cant capital, which deters the investment

  5. Deformation Behavior of Sub-micron and Micron Sized Alumina Particles in Compression.

    SciTech Connect (OSTI)

    Sarobol, Pylin; Chandross, Michael E.; Carroll, Jay; Mook, William; Boyce, Brad; Kotula, Paul G.; McKenzie, Bonnie B.; Bufford, Daniel Charles; Hall, Aaron Christopher.

    2014-09-01T23:59:59.000Z

    The ability to integrate ceramics with other materials has been limited due to high temperature (>800degC) ceramic processing. Recently, researchers demonstrated a novel process , aerosol deposition (AD), to fabricate ceramic films at room temperature (RT). In this process, sub - micro n sized ceramic particles are accelerated by pressurized gas, impacted on the substrate, plastically deformed, and form a dense film under vacuum. This AD process eliminates high temperature processing thereby enabling new coatings and device integration, in which ceramics can be deposited on metals, plastics, and glass. However, k nowledge in fundamental mechanisms for ceramic particle s to deform and form a dense ceramic film is still needed and is essential in advancing this novel RT technology. In this wo rk, a combination of experimentation and atomistic simulation was used to determine the deformation behavior of sub - micron sized ceramic particle s ; this is the first fundamental step needed to explain coating formation in the AD process . High purity, singl e crystal, alpha alumina particles with nominal size s of 0.3 um and 3.0 um were examined. Particle characterization, using transmission electron microscopy (TEM ), showed that the 0.3 u m particles were relatively defect - free single crystals whereas 3.0 u m p articles were highly defective single crystals or particles contained low angle grain boundaries. Sub - micron sized Al 2 O 3 particles exhibited ductile failure in compression. In situ compression experiments showed 0.3um particles deformed plastically, fractured, and became polycrystalline. Moreover, dislocation activit y was observed within the se particles during compression . These sub - micron sized Al 2 O 3 particles exhibited large accum ulated strain (2 - 3 times those of micron - sized particles) before first fracture. I n agreement with the findings from experimentation , a tomistic simulation s of nano - Al 2 O 3 particles showed dislocation slip and significant plastic deformation during compressi on . On the other hand, the micron sized Al 2 O 3 particles exhibited brittle f racture in compression. In situ compression experiments showed 3um Al 2 O 3 particles fractured into pieces without observable plastic deformation in compression. Particle deformation behaviors will be used to inform Al 2 O 3 coating deposition parameters and particle - particle bonding in the consolidated Al 2 O 3 coatings.

  6. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    E-Print Network [OSTI]

    Rutqvist, J.

    2013-01-01T23:59:59.000Z

    Williams, Compressed air energy storage: Theory, resources,for the compressed air energy storage technology by thefor compressed air energy storage power generation, Japan

  7. The roles of depth varying mechanical properties and permeability of the deep boundary condition in confined compression of articular cartilage

    E-Print Network [OSTI]

    Lee, John J.

    2011-01-01T23:59:59.000Z

    confined compression creep test of normal and proteoglycan-confined compression creep test of normal and proteoglycan-a stress-relaxation or creep test in confined compression,

  8. Efficient Spectral Broadening in the 100-W Average Power Regime Using Gas Filled Kagome HC-PCF and Pulse Compression

    E-Print Network [OSTI]

    Emaury, Florian; Debord, Benoit; Ghosh, Debashri; Diebold, Andreas; Gerome, Frederic; Suedmeyer, Thomas; Benabid, Fetah; Keller, Ursula

    2014-01-01T23:59:59.000Z

    We present nonlinear pulse compression of a high-power SESAM-modelocked thin-disk laser (TDL) using an Ar-filled hypocycloid-core Kagome Hollow-Core Photonic Crystal Fiber (HC-PCF). The output of the modelocked Yb:YAG TDL with 127 W average power, a pulse repetition rate of 7 MHz, and a pulse duration of 740 fs was spectrally broadened 16-fold while propagating in a Kagome HC-PCF containing 13 bar of static Argon gas. Subsequent compression tests performed using 8.4% of the full available power resulted in a pulse duration as short as 88 fs using the spectrally broadened output from the fiber. Compressing the full transmitted power through the fiber (118 W) could lead to a compressed output of >100 W of average power and >100 MW of peak power with an average power compression efficiency of 88%. This simple laser system with only one ultrafast laser oscillator and a simple single-pass fiber pulse compressor, generating both high peak power >100 MW and sub-100-fs pulses at megahertz repetition rate, is very int...

  9. MAGNESIUM ISOTOPE RATIOS IN {omega} CENTAURI RED GIANTS

    SciTech Connect (OSTI)

    Da Costa, G. S.; Norris, John E.; Yong, David [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 0200 (Australia)

    2013-05-20T23:59:59.000Z

    We have used the high-resolution observations obtained at the Anglo-Australian Telescope with Ultra-High Resolution Facility (R {approx} 100,000) and at Gemini-S with b-HROS (R {approx} 150,000) to determine magnesium isotope ratios for seven {omega} Cen red giants that cover a range in iron abundance from [Fe/H] = -1.78 to -0.78 dex, and for two red giants in M4 (NGC 6121). The {omega} Cen stars sample both the ''primordial'' (i.e., O-rich, Na- and Al-poor) and the ''extreme'' (O-depleted, Na- and Al-rich) populations in the cluster. The primordial population stars in both {omega} Cen and M4 show ({sup 25}Mg, {sup 26}Mg)/{sup 24}Mg isotopic ratios that are consistent with those found for the primordial population in other globular clusters with similar [Fe/H] values. The isotopic ratios for the {omega} Cen extreme stars are also consistent with those for extreme population stars in other clusters. The results for the extreme population stars studied indicate that the {sup 26}Mg/{sup 24}Mg ratio is highest at intermediate metallicities ([Fe/H] < -1.4 dex), and for the highest [Al/Fe] values. Further, the relative abundance of {sup 26}Mg in the extreme population stars is notably higher than that of {sup 25}Mg, in contrast to model predictions. The {sup 25}Mg/{sup 24}Mg isotopic ratio in fact does not show any obvious dependence on either [Fe/H] or [Al/Fe] nor, intriguingly, any obvious difference between the primordial and extreme population stars.

  10. Direct Injection Compression Ignition Diesel Automotive Technology Education GATE Program

    SciTech Connect (OSTI)

    Anderson, Carl L

    2006-09-25T23:59:59.000Z

    The underlying goal of this prqject was to provide multi-disciplinary engineering training for graduate students in the area of internal combustion engines, specifically in direct injection compression ignition engines. The program was designed to educate highly qualified engineers and scientists that will seek to overcome teclmological barriers preventing the development and production of cost-effective high-efficiency vehicles for the U.S. market. Fu1iher, these highly qualified engineers and scientists will foster an educational process to train a future workforce of automotive engineering professionals who are knowledgeable about and have experience in developing and commercializing critical advanced automotive teclmologies. Eight objectives were defmed to accomplish this goal: 1. Develop an interdisciplinary internal co1nbustion engine curriculum emphasizing direct injected combustion ignited diesel engines. 2. Encourage and promote interdisciplinary interaction of the faculty. 3. Offer a Ph.D. degree in internal combustion engines based upon an interdisciplinary cuniculum. 4. Promote strong interaction with indusuy, develop a sense of responsibility with industry and pursue a self sustaining program. 5. Establish collaborative arrangements and network universities active in internal combustion engine study. 6. Further Enhance a First Class educational facility. 7. Establish 'off-campus' M.S. and Ph.D. engine programs of study at various indusuial sites. 8. Extend and Enhance the Graduate Experience.

  11. Hydro-mechanical behavior of Municipal Solid Waste subject to leachate recirculation in a large-scale compression reactor cell

    SciTech Connect (OSTI)

    Olivier, Franck [Environment, Energy and Waste Research Center (CREED), 291, avenue Dreyfous Ducas, 78520 Limay (France) and Laboratoire LIRIGM - Maison des Geosciences, 1381, rue de la piscine 38400 Saint-Martin d'Heres (France)]. E-mail: franck.olivier@ujf-grenoble.fr; Gourc, Jean-Pierre [Laboratoire LIRIGM - Maison des Geosciences, 1381, rue de la piscine 38400 Saint-Martin d'Heres (France)]. E-mail: gourc@ujf-grenoble.fr

    2007-07-01T23:59:59.000Z

    The paper presents the results of a laboratory experiment on Municipal Solid Waste (MSW) subjected to one-dimensional compression in a 1 m{sup 3} instrumented cell. The focus was on the hydro-mechanical behavior of the material under conditions of confinement and leachate percolation that replicate those found in real-scale landfills. The operation of the apparatus is detailed together with the testing methodology and the monitoring program. Two samples of waste were tested: the first extended over a period of 10 months ('Control Test') and the second for 22 months ('Enhanced Test' with leachate recirculation). Consolidation data is reported with regard to both short-term (stress-dependent) and long-term (time-dependent) settlements. A discussion follows based on the derived values of primary and secondary compression ratios. Correlations between compression parameters and the biodegradation process are presented. In particular, results clearly highlight the effect of leachate recirculation on waste settlement: 24% secondary deformation reached after slightly less than 2 years (equivalent to a 5-fold increase in compressibility) and 17.9% loss of dry matter. Comparisons are proposed considering the results derived from the few monitoring programs conducted on experimental bioreactors worldwide. Finally, the hydraulic characterization of waste is discussed with regard to the evaluation of effective porosity and permeability.

  12. Matched metal die compression molded structural random fiber sheet molding compound flywheel

    DOE Patents [OSTI]

    Kulkarni, Satish V. (San Ramon, CA); Christensen, Richard M. (Danville, CA); Toland, Richard H. (West Chester, PA)

    1985-01-01T23:59:59.000Z

    A flywheel (10) is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel (10) has a body of essentially planar isotropic high strength structural random fiber sheet molding compound (SMC-R). The flywheel (10) may be economically produced by a matched metal die compression molding process. The flywheel (10) makes energy intensive efficient use of a fiber/resin composite while having a shape designed by theory assuming planar isotropy.

  13. Matched metal die compression molded structural random fiber sheet molding compound flywheel. [Patent application

    DOE Patents [OSTI]

    Kulkarni, S.V.; Christensen, R.M.; Toland, R.H.

    1980-09-24T23:59:59.000Z

    A flywheel is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel has a body of essentially planar isotropic high strength structural random fiber sheet molding compound (SMC-R). The flywheel may be economically produced by a matched metal die compression molding process. The flywheel makes energy intensive efficient use of a fiber/resin composite while having a shape designed by theory assuming planar isotropy.

  14. Low-pressure-ratio regenerative exhaust-heated gas turbine. Final report

    SciTech Connect (OSTI)

    Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.

    1991-01-01T23:59:59.000Z

    A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.

  15. The impact of equivalence ratio oscillations on combustion dynamics in a backward-facing step combustor

    SciTech Connect (OSTI)

    Murat Altay, H.; Speth, Raymond L.; Hudgins, Duane E.; Ghoniem, Ahmed F. [Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, MA 02139 (United States)

    2009-11-15T23:59:59.000Z

    The combustion dynamics of propane-air flames are investigated in an atmospheric pressure, atmospheric inlet temperature, lean, premixed backward-facing step combustor. We modify the location of the fuel injector to examine the impact of equivalence ratio oscillations arriving at the flame on the combustion dynamics. Simultaneous pressure, velocity, heat-release rate and equivalence ratio measurements and high-speed video from the experiments are used to identify and characterize several distinct operating modes. When the fuel is injected far upstream from the step, the equivalence ratio arriving at the flame is steady and the combustion dynamics are controlled only by flame-vortex interactions. In this case, different dynamic regimes are observed depending on the operating parameters. When the fuel is injected close to the step, the equivalence ratio arriving at the flame exhibits oscillations. In the presence of equivalence ratio oscillations, the measured sound pressure level is significant across the entire range of lean mean equivalence ratios even if the equivalence ratio oscillations arriving at the flame are out-of-phase with the pressure oscillations. The combustion dynamics are governed primarily by the flame-vortex interactions, while the equivalence ratio oscillations have secondary effects. The equivalence ratio oscillations could generate variations in the combustion dynamics in each cycle under some operating conditions, destabilize the flame at the entire range of the lean equivalence ratios, and increase the value of the mean equivalence ratio at the lean blowout limit. (author)

  16. Simple lossless and near-lossless waveform compression Tony Robinson

    E-Print Network [OSTI]

    Lazar, Aurel A.

    these requirements. A signi cant application of this program is to the problem of compression of speech les problems associated with general waveform compression, namely predictive modelling and residual coding at the xed bit rate. Similarly there has been much work in design of general purpose lossless compressors

  17. Mesh Geometry Compression for Mobile Graphics Jongseok Lee

    E-Print Network [OSTI]

    Lee, Seungyong

    , for mobile graphics, API standards such as OpenGL ES and JSR-184 have been proposed [8], and the graphicsMesh Geometry Compression for Mobile Graphics Jongseok Lee POSTECH thirdeye@postech.ac.kr Sungyul--This paper presents a compression scheme for mesh geometry, which is suitable for mobile graphics. The main

  18. TIME-PERIODIC SOUND WAVE PROPAGATION COMPRESSIBLE EULER EQUATIONS

    E-Print Network [OSTI]

    A PARADIGM FOR TIME-PERIODIC SOUND WAVE PROPAGATION IN THE COMPRESSIBLE EULER EQUATIONS BLAKE consistent with time-periodic sound wave propagation in the 3 Ã? 3 nonlinear compressible Euler equations description of shock-free waves that propagate through an oscillating entropy field without breaking or dis

  19. Lossless Wavelet Based Image Compression with Adaptive 2D Decomposition

    E-Print Network [OSTI]

    Lossless Wavelet Based Image Compression with Adaptive 2D Decomposition Manfred Kopp Technical.kopp@ieee.org WWW: http://www.cg.tuwien.ac.at/~kopp/ Abstract 2D wavelets are usually generated from 1D wavelets wavelet functions based on the compression of the coefficients, but needs only the same number of 1D

  20. Techno-economic Performance Evaluation of Compressed Air

    E-Print Network [OSTI]

    PNNL-22235 Techno-economic Performance Evaluation of Compressed Air Energy Storage in the Pacific of Compressed Air Energy Storage in the Pacific Northwest BP McGrail JE Cabe CL Davidson FS Knudsen DH Bacon MD air energy storage (CAES) in the unique geologic setting of inland Washington and Oregon. The basic

  1. Recovery of partially occluded objects by applying compressive Fresnel holography

    E-Print Network [OSTI]

    Rosen, Joseph

    Recovery of partially occluded objects by applying compressive Fresnel holography Yair Rivenson,1, 2012; posted March 2, 2012 (Doc. ID 161160); published May 15, 2012 A compressive Fresnel holography, and is given by px. This may be regarded as a subsampling of the object's Fresnel field; hence the motivation

  2. Homogeneous Charge Compression Ignition: Formulation Effect of a Diesel Fuel

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Homogeneous Charge Compression Ignition: Formulation Effect of a Diesel Fuel on the Initiation and the Combustion Potential of Olefin Impact in a Diesel Base Fuel D. Alseda1,2, X. Montagne1 and P. Dagaut2 1 Compression Ignition: Formulation Effect of a Diesel Fuel on the Initiation and the Combustion - Potential

  3. Compressed Gas Cylinder Safety I. Background. Due to the nature

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    Compressed Gas Cylinder Safety I. Background. Due to the nature of gas cylinders hazards of a ruptured cylinder. There are almost 200 different types of materials in gas cylinders, there are several general procedures to follow for safe storage and handling of a compressed gas cylinder: II

  4. Simplified Compression of Redundancy Free Trellis Sections in Turbo Decoder

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Simplified Compression of Redundancy Free Trellis Sections in Turbo Decoder Emmanuel Boutillon that for an M state Turbo decoder, among the L compressed trellis stages, only m = 3 or even m = 2 are necessary turbo-code and/or to reduce its power consumption.1 I. INTRODUCTION The quality of an error control code

  5. Gasoline surrogate modeling of gasoline ignition in a rapid compression machine and comparison to experiments

    SciTech Connect (OSTI)

    Mehl, M; Kukkadapu, G; Kumar, K; Sarathy, S M; Pitz, W J; Sung, S J

    2011-09-15T23:59:59.000Z

    The use of gasoline in homogeneous charge compression ignition engines (HCCI) and in duel fuel diesel - gasoline engines, has increased the need to understand its compression ignition processes under engine-like conditions. These processes need to be studied under well-controlled conditions in order to quantify low temperature heat release and to provide fundamental validation data for chemical kinetic models. With this in mind, an experimental campaign has been undertaken in a rapid compression machine (RCM) to measure the ignition of gasoline mixtures over a wide range of compression temperatures and for different compression pressures. By measuring the pressure history during ignition, information on the first stage ignition (when observed) and second stage ignition are captured along with information on the phasing of the heat release. Heat release processes during ignition are important because gasoline is known to exhibit low temperature heat release, intermediate temperature heat release and high temperature heat release. In an HCCI engine, the occurrence of low-temperature and intermediate-temperature heat release can be exploited to obtain higher load operation and has become a topic of much interest for engine researchers. Consequently, it is important to understand these processes under well-controlled conditions. A four-component gasoline surrogate model (including n-heptane, iso-octane, toluene, and 2-pentene) has been developed to simulate real gasolines. An appropriate surrogate mixture of the four components has been developed to simulate the specific gasoline used in the RCM experiments. This chemical kinetic surrogate model was then used to simulate the RCM experimental results for real gasoline. The experimental and modeling results covered ultra-lean to stoichiometric mixtures, compressed temperatures of 640-950 K, and compression pressures of 20 and 40 bar. The agreement between the experiments and model is encouraging in terms of first-stage (when observed) and second-stage ignition delay times and of heat release rate. The experimental and computational results are used to gain insight into low and intermediate temperature processes during gasoline ignition.

  6. Video compression with 1-D directional transforms in H.264/AVC

    E-Print Network [OSTI]

    Kamisli, Fatih

    Typically the same transforms, such as the 2-D Discrete Cosine Transform (DCT), are used to compress both images in image compression and prediction residuals in video compression. However, these two signals have different ...

  7. Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about Uncertainty

    E-Print Network [OSTI]

    McGregor, Andrew

    Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about: April 29, 2014 #12;Coding for Transmission Coding for Compression Bonus Section Information Theory. #12;Coding for Transmission Coding for Compression Bonus Section Encoding Messages with Redundancy

  8. Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about Uncertainty

    E-Print Network [OSTI]

    McGregor, Andrew

    Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about 1, 2013 #12;Coding for Transmission Coding for Compression Bonus Section Information Theory Encoding for Transmission Coding for Compression Bonus Section Encoding Messages with Redundancy: Error Correcting Suppose

  9. Vacuum/Compression Valving (VCV) Using Parrafin-Wax on a Centrifugal Microfluidic CD Platform

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Volume 8 | Issue 3 | e58523 Vacuum/Compression Valving (VCV)Vacuum/Compression Valving (VCV) Using Parrafin-Wax on aThis paper introduces novel vacuum/compression valves (VCVs)

  10. Correlation and image compression for limited-bandwidth CCD.

    SciTech Connect (OSTI)

    Thompson, Douglas G.

    2005-07-01T23:59:59.000Z

    As radars move to Unmanned Aerial Vehicles with limited-bandwidth data downlinks, the amount of data stored and transmitted with each image becomes more significant. This document gives the results of a study to determine the effect of lossy compression in the image magnitude and phase on Coherent Change Detection (CCD). We examine 44 lossy compression types, plus lossless zlib compression, and test each compression method with over 600 CCD image pairs. We also derive theoretical predictions for the correlation for most of these compression schemes, which compare favorably with the experimental results. We recommend image transmission formats for limited-bandwidth programs having various requirements for CCD, including programs which cannot allow performance degradation and those which have stricter bandwidth requirements at the expense of CCD performance.

  11. Combustion dynamics in steady compressible flows

    E-Print Network [OSTI]

    S. Berti; D. Vergni; A. Vulpiani

    2008-07-03T23:59:59.000Z

    We study the evolution of a reactive field advected by a one-dimensional compressible velocity field and subject to an ignition-type nonlinearity. In the limit of small molecular diffusivity the problem can be described by a spatially discretized system, and this allows for an efficient numerical simulation. If the initial field profile is supported in a region of size l < lc one has quenching, i.e., flame extinction, where lc is a characteristic length-scale depending on the system parameters (reacting time, molecular diffusivity and velocity field). We derive an expression for lc in terms of these parameters and relate our results to those obtained by other authors for different flow settings.

  12. Seneca Compressed Air Energy Storage (CAES) Project

    SciTech Connect (OSTI)

    None

    2012-11-30T23:59:59.000Z

    This report provides a review and an analysis of potential environmental justice areas that could be affected by the New York State Electric & Gas (NYSEG) compress air energy storage (CAES) project and identifies existing environmental burden conditions on the area and evaluates additional burden of any significant adverse environmental impact. The review assesses the socioeconomic and demographic conditions of the area surrounding the proposed CAES facility in Schuyler County, New York. Schuyler County is one of 62 counties in New York. Schuyler County’s 2010 population of 18,343 makes it one of the least populated counties in the State (U.S. Census Bureau, 2010). This report was prepared for WorleyParsons by ERM and describes the study area investigated, methods and criteria used to evaluate this area, and the findings and conclusions from the evaluation.

  13. Quantum Bootstrapping via Compressed Quantum Hamiltonian Learning

    E-Print Network [OSTI]

    Nathan Wiebe; Christopher Granade; David G. Cory

    2015-03-30T23:59:59.000Z

    Recent work has shown that quantum simulation is a valuable tool for learning empirical models for quantum systems. We build upon these results by showing that a small quantum simulators can be used to characterize and learn control models for larger devices for wide classes of physically realistic Hamiltonians. This leads to a new application for small quantum computers: characterizing and controlling larger quantum computers. Our protocol achieves this by using Bayesian inference in concert with Lieb-Robinson bounds and interactive quantum learning methods to achieve compressed simulations for characterization. Whereas Fisher information analysis shows that current methods which employ short-time evolution are suboptimal, interactive quantum learning allows us to overcome this limitation. We illustrate the efficiency of our bootstrapping protocol by showing numerically that an 8-qubit Ising model simulator can be used to calibrate and control a 50 qubit Ising simulator while using only about 750 kilobits of experimental data.

  14. Shock compression of low-density foams

    SciTech Connect (OSTI)

    Holmes, N.C.

    1993-07-01T23:59:59.000Z

    Shock compression of very low density micro-cellular materials allows entirely new regimes of hot fluid states to be investigated experimentally. Using a two-stage light-gas gun to generate strong shocks, temperatures of several eV are readily achieved at densities of roughly 0.5--1 g/cm{sup 3} in large, uniform volumes. The conditions in these hot, expanded fluids are readily found using the Hugoniot jump conditions. We will briefly describe the basic methodology for sample preparation and experimental measurement of shock velocities. We present data for several materials over a range of initial densities. This paper will explore the applications of these methods for investigations of equations of state and phase diagrams, spectroscopy, and plasma physics. Finally, we discus the need for future work on these and related low-density materials.

  15. Environmental control on eastern broadleaf forest species' leaf wax distributions and D/H ratios

    E-Print Network [OSTI]

    Environmental control on eastern broadleaf forest species' leaf wax distributions and D/H ratios the degree to which an individual plant's leaf waxes D/H ratios are affected by these parameters remains- sitions of leaf wax n-alkanes, stem and surface waters were analyzed and compared against high

  16. Radioactive anomaly discrimination from spectral ratios

    DOE Patents [OSTI]

    Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements

    2013-08-20T23:59:59.000Z

    A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.

  17. Revenue Maximization of Electricity Generation for a Wind Turbine Integrated with a Compressed Air Energy Storage System

    E-Print Network [OSTI]

    Li, Perry Y.

    Energy Storage System Mohsen Saadat, Farzad A. Shirazi, Perry Y. Li Abstract-- A high-level supervisory controller is developed for a Compressed Air Energy Storage (CAES) system integrated with a wind turbine the effect of storage system sizing on the maximum revenue. I. INTRODUCTION Large-scale cost effective energy

  18. Bursty Impulse Noise Detection by Compressed University of British Columbia, Vancouver, BC, Canada, lampe@ece.ubc.ca

    E-Print Network [OSTI]

    Lampe, Lutz

    wires, no need to purchase spectrum), high penetration of the power distribution grid, and ease of use for data transmission over power lines. For power line communi- cations (PLC) systems with bandwidths application of CS for IN detection. Index Terms--Power line communications (PLC), impulse noise, compressed

  19. The Effect of Turbulent Mixing on Compression Ignition of a Lean Hydrogen/Air Mixture Jacqueline H. Chen1

    E-Print Network [OSTI]

    Im, Hong G.

    automotive engines known as homogeneous charge compression ignition combustion (HCCI). By operating under overall fuel-lean conditions, and hence, at lower temperatures, HCCI can potentially achieve high engine, the primary mode of combustion in this regime is thought to occur by volumetric autoignition. Therefore, HCCI

  20. Compressed sensing quantum process tomography for superconducting quantum gates

    E-Print Network [OSTI]

    Andrey V. Rodionov; Andrzej Veitia; R. Barends; J. Kelly; Daniel Sank; J. Wenner; John M. Martinis; Robert L. Kosut; Alexander N. Korotkov

    2014-07-03T23:59:59.000Z

    We apply the method of compressed sensing (CS) quantum process tomography (QPT) to characterize quantum gates based on superconducting Xmon and phase qubits. Using experimental data for a two-qubit controlled-Z gate, we obtain an estimate for the process matrix $\\chi$ with reasonably high fidelity compared to full QPT, but using a significantly reduced set of initial states and measurement configurations. We show that the CS method still works when the amount of used data is so small that the standard QPT would have an underdetermined system of equations. We also apply the CS method to the analysis of the three-qubit Toffoli gate with numerically added noise, and similarly show that the method works well for a substantially reduced set of data. For the CS calculations we use two different bases in which the process matrix $\\chi$ is approximately sparse, and show that the resulting estimates of the process matrices match each ther with reasonably high fidelity. For both two-qubit and three-qubit gates, we characterize the quantum process by not only its process matrix and fidelity, but also by the corresponding standard deviation, defined via variation of the state fidelity for different initial states.

  1. EA-1752: Pacific Gas & Electric Company (PG&E), Compressed Air...

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

    52: Pacific Gas & Electric Company (PG&E), Compressed Air Energy Storage (CAES) Compression Testing Phase Project, San Joaquin County, California EA-1752: Pacific Gas & Electric...

  2. Lung Toxicity and Mutagenicity of Emissions From Heavy-Duty Compressed...

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

    Lung Toxicity and Mutagenicity of Emissions From Heavy-Duty Compressed Natural Gas (CNG)-Powered Vehicles Lung Toxicity and Mutagenicity of Emissions From Heavy-Duty Compressed...

  3. A Decision-Based Analysis of Compressed Air Usage Patterns in Automotive Manufacturing

    E-Print Network [OSTI]

    Yuan, Chris; Zhang, Teresa; Rangarajan, Arvind; Dornfeld, David; Ziemba, Bill; Whitbeck, Rod

    2006-01-01T23:59:59.000Z

    Air Usage Patterns in Automotive Manufacturing Chris Y. Yuanper vehicle built from automotive manufacturing facilities,2004). Compressed Air in Automotive Manufacturing Compressed

  4. SU-E-J-48: Development of An Abdominal Compression Device for Respiratory Correlated Radiation Therapy

    SciTech Connect (OSTI)

    Kim, T; Kang, S; Kim, D; Suh, T [Catholic University Medical College, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: The aim of this study is to develop the abdominal compression device which could control pressure level according to the abdominal respiratory motion and evaluate its feasibility. Methods: In this study, we focused on developing the abdominal compression device which could control pressure level at any point of time so the developed device is possible to use a variety of purpose (gating technique or respiratory training system) while maintaining the merit of the existing commercial device. The compression device (air pad form) was designed to be able to compress the front and side of abdomen and the pressure level of the abdomen is controlled by air flow. Pressure level of abdomen (air flow) was determined using correlation data between external abdominal motion and respiratory volume signal measured by spirometer. In order to verify the feasibility of the device, it was necessary to confirm the correlation between the abdominal respiratory motion and respiratory volume signal and cooperation with respiratory training system also checked. Results: In the previous study, we could find that the correlation coefficient ratio between diaphragm and respiratory volume signal measured by spirometer was 0.95. In this study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion measured by belt-transducer (correlation coefficient ratio was 0.92) and used the correlated respiratory volume data as an abdominal pressure level. It was possible to control the pressure level with negligible time delay and respiratory volume data based guiding waveforms could be properly inserted into the respiratory training system. Conclusion: Through this feasibility study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion. Also initial assessment of the device and its compatibility with the respiratory training system were verified. Further study on application in respiratory gated therapy and respiratory training system will be investigated. This work was supported by Radiation Technology R and D program (No. 2013M2A2A7043498)and Basic Atomic Energy Research Institute (BAERI)(No. NRF-2009-0078390) through the National Research Foundation of Korea funded by the Ministry of Science, ICT and Future Planning.

  5. OXYGEN ISOTOPIC RATIOS IN COOL R CORONAE BOREALIS STARS

    SciTech Connect (OSTI)

    Garcia-Hernandez, D. A. [Instituto de Astrofisica de Canarias (IAC), C/Via Lactea s/n, 38200 La Laguna, Tenerife (Spain); Lambert, David L. [W. J. McDonald Observatory, University of Texas at Austin. 1 University Station, C1400. Austin, TX 78712-0259 (United States); Rao, N. Kameswara [Indian Institute of Astrophysics, Bangalore 560 034 (India); Hinkle, Ken H. [National Optical Astronomy Observatory (NOAO), Tucson, AZ 85726 (United States); Eriksson, Kjell, E-mail: agarcia@iac.e, E-mail: dll@astro.as.utexas.ed, E-mail: nkrao@iiap.res.i, E-mail: hinkle@noao.ed, E-mail: Kjell.Eriksson@astro.uu.s [Department of Physics and Astronomy, Uppsala University, Box 515, 75120 Uppsala (Sweden)

    2010-05-01T23:59:59.000Z

    We investigate the relationship between R Coronae Borealis (RCB) stars and hydrogen-deficient carbon (HdC) stars by measuring precise {sup 16}O/{sup 18}O ratios for five cool RCB stars. The {sup 16}O/{sup 18}O ratios are derived by spectrum synthesis from high-resolution (R {approx} 50, 000) K-band spectra. Lower limits to the {sup 16}O/{sup 17}O and {sup 14}N/{sup 15}N ratios as well as Na and S abundances (when possible) are also given. RCB stars in our sample generally display less {sup 18}O than HdC stars-the derived {sup 16}O/{sup 18}O ratios range from 3 to 20. The only exception is the RCB star WX CrA, which seems to be an HdC-like star with {sup 16}O/{sup 18}O = 0.3. Our result of a higher {sup 16}O/{sup 18}O ratio for the RCB stars must be accounted for by a theory of the formation and evolution of HdC and RCB stars. We speculate that a late dredge-up of products of He burning, principally {sup 12}C and {sup 16}O, may convert an {sup 18}O-rich HdC star into an {sup 18}O-poor RCB star as the H-deficient star begins its final evolution from a cool supergiant to the top of the white dwarf cooling track.

  6. Fission Product Ratios as Treaty Monitoring Discriminants

    SciTech Connect (OSTI)

    Miley, Harry S.; Bowyer, Ted W.; Greenwood, Lawrence R.; Arthur, Richard J.

    2008-05-15T23:59:59.000Z

    The International Monitoring System (IMS) of the Comprehensive Test Ban Treaty Organization (CTBTO) is currently under construction. The IMS is intended for monitoring of nuclear explosions. The radionuclide branch of the IMS monitors the atmosphere for short-lived radioisotopes indicative of a nuclear weapon test, and includes field collection and measurement stations, as well as laboratories to provide reanalysis of the most important samples and a quality control function. The Pacific Northwest National Laboratory in Richland, Washington hosts the United States IMS laboratory, with the designation “RL16.” Since acute reactor containment failures and chronic reactor leakage may also produce similar isotopes, it is tempting to compute ratios of detected isotopes to determine the relevance of an event to the treaty or agreement in question. In this paper we will note several shortcomings of simple isotopic ratios: (1) fractionation of different chemical species, (2) difficulty in comparing isotopes within a single element, (3) the effect of unknown decay times. While these shortcomings will be shown in the light of an aerosol sample, several of the problems extend to xenon isotopic ratios. The result of the difficulties listed above is that considerable human expertise will be required to convert a simple mathematical ratio into a criterion which will reliably categorize an event as ‘reactor’ or ‘weapon’.

  7. Viscosity to entropy ratio at extremality

    E-Print Network [OSTI]

    Sayan K. Chakrabarti; Sachin Jain; Sudipta Mukherji

    2010-01-19T23:59:59.000Z

    Assuming gauge theory realization at the boundary, we show that the viscosity to entropy ratio is 1/(4 pi) where the bulk is represented by a large class of extremal black holes in anti-de Sitter space. In particular, this class includes multiple R-charged black holes in various dimensions.

  8. Ratio method of measuring $w$ boson mass

    SciTech Connect (OSTI)

    Guo, Feng; /SUNY, Stony Brook

    2010-08-01T23:59:59.000Z

    This dissertation describes an alternative method of measuring the W boson mass in D0 experiment. Instead of extracting M{sub W} from the fitting of W {yields} e{nu} fast Monte Carlo simulations to W {yields} e{nu} data as in the standard method, we make the direct fit of transverse mass between W {yields} e{nu} data and Z {yields} ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (M{sub W}/M{sub Z}). Given the precisely measured Z boson mass, W mass is directly fitted from W {yields} e{nu} and Z {yields} ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb{sup -1} D0 Run IIa dataset, ratio method gives M{sub W} = 80435 {+-} 43(stat) {+-} 26(sys) MeV.

  9. E-Print Network 3.0 - aspect ratio x-ray Sample Search Results

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

    0953-89841825S17 Summary: the power ratio of beam splitting. With centralized remote control, heating and x-ray diffraction... for in situ x-ray diffraction at high...

  10. The Wavelet Trie: Maintaining an Indexed Sequence of Strings in Compressed Space

    E-Print Network [OSTI]

    Grossi, Roberto

    2012-01-01T23:59:59.000Z

    An indexed sequence of strings is a data structure for storing a string sequence that supports random access, searching, range counting and analytics operations, both for exact matches and prefix search. String sequences lie at the core of column-oriented databases, log processing, and other storage and query tasks. In these applications each string can appear several times and the order of the strings in the sequence is relevant. The prefix structure of the strings is relevant as well: common prefixes are sought in strings to extract interesting features from the sequence. Moreover, space-efficiency is highly desirable as it translates directly into higher performance, since more data can fit in fast memory. We introduce and study the problem of compressed indexed sequence of strings, representing indexed sequences of strings in nearly-optimal compressed space, both in the static and dynamic settings, while preserving provably good performance for the supported operations. We present a new data structure for...

  11. Compression of solid N/sub 2/ at 296 K from 5 to 10 GPa

    SciTech Connect (OSTI)

    Olinger, B.

    1984-02-01T23:59:59.000Z

    The volume of solid N/sub 2/ having Pm3n space group was measured at 296 K from 5 to 10 GPa using a high pressure, x-ray diffraction technique. The compression of NaF was used as the pressure gauge. From a fit of the compression of the Pm3n structure data converted to the velocity plane, the volumes and bulk moduli are calculated as a function of pressure. From this fit and simultaneous volume measurements of the ..beta..-N/sub 2/ phase and the Pm3n structure, the pressure of transformation from the ..beta..-N/sub 2/ phase to the Pm3n structure is found to be 4.8 GPa. Recently published a priori calculations are shown to agree well with the present data.

  12. Influence of temperature and strain rate on the compressive behavior of PMMA and polycarbonate polymers

    SciTech Connect (OSTI)

    Cady, C. M. (Carl McElhinney); Lopez, M. F. (Mike F.); Gray, G. T. (George T.), III; Idar, D. J. (Deanne J.); Blumenthal, W. R. (William R.)

    2001-01-01T23:59:59.000Z

    Compression stress-strain measurements have been made on commercial polymethylmethacrylate (PMMA) and polycarbonate (PC) polymers as a function of tcmperature (-197 C to 220 C) and strain rate. A split-Hopkinson-pressure bar (SJIPU) was used to achieve strain rates of about 2500 s-' and a servohydraulic tester was used for lower strain rate testing (0.001 to 5 s-'). The mechanical response of these transparent polymers is quite different. The strength of PC is weakly dependent on strain rate, only moderately dependent on temperature, and remains ductile to -197OC. In contrast, the strength of PMMA is linearly dependent on temperature and strongly dependent on strain rate. Significantly, PMMA develops cracking and fails in compression with little ductility ( 7 4 % total strain) at either low strain rates and very low temperatures (-197OC) or at high strain rates and temperatures very near ambient.

  13. Lattice Anharmonicity and Thermal Conductivity from Compressive Sensing of First-Principles Calculations

    SciTech Connect (OSTI)

    Zhou, Fei [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nielson, Weston [Univ. of California, Los Angeles, CA (United States); Xia, Yi [Univ. of California, Los Angeles, CA (United States); Ozoli?š, Vidvuds [Univ. of California, Los Angeles, CA (United States)

    2014-10-01T23:59:59.000Z

    First-principles prediction of lattice thermal conductivity ?L of strongly anharmonic crystals is a long-standing challenge in solid-state physics. Making use of recent advances in information science, we propose a systematic and rigorous approach to this problem, compressive sensing lattice dynamics. Compressive sensing is used to select the physically important terms in the lattice dynamics model and determine their values in one shot. Nonintuitively, high accuracy is achieved when the model is trained on first-principles forces in quasirandom atomic configurations. The method is demonstrated for Si, NaCl, and Cu12Sb4S13, an earth-abundant thermoelectric with strong phonon-phonon interactions that limit the room-temperature ?L to values near the amorphous limit.

  14. EFFECT OF COMPRESSION ON CONDUCTIVITY AND MORPHOLOGY OF PFSA MEMBRANES

    SciTech Connect (OSTI)

    Kusoglu, Ahmet; Weber, Adam; Jiang, Ruichin; Gittleman, Craig

    2011-07-20T23:59:59.000Z

    Polymer-Electrolyte-Fuel-Cells (PEFCs) are promising candidates for powering vehicles and portable devices using renewable-energy sources. The core of a PEFC is the solid electrolyte membrane that conducts protons from anode to cathode, where water is generated. The conductivity of the membrane, however, depends on the water content of the membrane, which is strongly related to the cell operating conditions. The membrane and other cell components are typically compressed to minimize various contact resistances. Moreover, the swelling of a somewhat constrained membrane in the cell due to the humidity changes generates additional compressive stresses in the membrane. These external stresses are balanced by the internal swelling pressure of the membrane and change the swelling equilibrium. It was shown using a fuel-cell setup that compression could reduce the water content of the membrane or alter the cell resistance. Nevertheless, the effect of compression on the membrane’s transport properties is yet to be understood, as well as its implications in the structure-functions relationships of the membrane. We previously studied, both experimentally and theoretically, how compression affects the water content of the membrane.6 However, more information is required the gain a fundamental understanding of the compression effects. In this talk, we present the results of our investigation on the in-situ conductivity of the membrane as a function of humidity and cell compression pressure. Moreover, to better understand the morphology of compressed membrane, small-angle X-ray-scattering (SAXS) experiments were performed. The conductivity data is then analyzed by investigating the size of the water domains of the compressed membrane determined from the SAXS measurements.

  15. Stresses resulting from compression of bulk cotton lint fibers

    E-Print Network [OSTI]

    Chimbombi, Ezekiel Maswe

    1998-01-01T23:59:59.000Z

    MTS and Anthony's models 43 4. 2 Mean resilient force on the model bale per time FIGURE Page 4. 3 Ansys output of stress state in a compressed cotton bale 4. 4 Ansys output of state of strain in a compressed cotton bale 47 48 4. 5 Nodal forces... compressed bales is important so that it can be handled in the channels of trade (McCaskill and Anthony, 1977). Anthony et al. (1994) reported that the packaging system consists of a battery condenser, lint slide, lint feeder, tramper, bale press, and bale...

  16. All Metal Iron Core For A Low Aspect Ratio Tokamak

    SciTech Connect (OSTI)

    D.A. Gates, C. Jun, I. Zatz, A. Zolfaghari

    2010-06-02T23:59:59.000Z

    A novel concept for incorporating a iron core transformer within a axisymmetric toroidal plasma containment device with a high neutron flux is described. This design enables conceptual design of low aspect ratio devices which employ standard transformer-driven plasma startup by using all-metal high resistance separators between the toroidal field windings. This design avoids the inherent problems of a multiturn air core transformer which will inevitably suffer from strong neutron bombardment and hence lose the integrity of its insulation, both through long term material degradation and short term neutron- induced conductivity.. A full 3-dimensional model of the concept has been developed within the MAXWELL program and the resultant loop voltage calculated. The utility of the result is found to be dependent on the resistivity of the high resistance separators. Useful loop voltage time histories have been obtained using achievable resistivities.

  17. Improved Grammar-Based Compressed Indexes

    E-Print Network [OSTI]

    Claude, Francisco

    2011-01-01T23:59:59.000Z

    We introduce the first grammar-compressed representation of a sequence that supports searches in time that depends only logarithmically on the size of the grammar. Given a text $T[1..u]$ that is represented by a (context-free) grammar of $n$ (terminal and nonterminal) symbols and size $N$ (measured as the sum of the lengths of the right hands of the rules), a basic grammar-based representation of $T$ takes $N\\lg n$ bits of space. Our representation requires $2N\\lg n + N\\lg u + \\epsilon\\, n\\lg n + o(N\\lg n)$ bits of space, for any $0<\\epsilon \\le 1$. It can find the positions of the $occ$ occurrences of a pattern of length $m$ in $T$ in $O((m^2/\\epsilon)\\lg (\\frac{\\lg u}{\\lg n}) +occ\\lg n)$ time, and extract any substring of length $\\ell$ of $T$ in time $O(\\ell+h\\lg(N/h))$, where $h$ is the height of the grammar tree.

  18. Analytical bunch compression studies for FLUTE

    E-Print Network [OSTI]

    Schreck, M

    2014-01-01T23:59:59.000Z

    The current article deals with analytical bunch compression studies for FLUTE whose results are compared to simulations. FLUTE is a linac-based electron accelerator with a design energy of approximately 40 MeV currently being constructed at the Karlsruhe Institute of Technology. One of the goals of FLUTE is to generate electron bunches with their length lying in the femtosecond regime. In the first phase this will be accomplished using a magnetic bunch compressor. This compressor forms the subject of the studies presented. The paper is divided into three parts. The first part deals with pure geometric investigations of the bunch compressor where space charge effects and the back reaction of bunches with coherent synchrotron radiation (CSR) are neglected. The second part is dedicated to the treatment of space charge effects and the third part gives some analytical results on the emission of CSR. The upshot is that the results of the first and the third part agree quite well with what is obtained from simulatio...

  19. Effect of Compressibility on the Annihilation Process

    E-Print Network [OSTI]

    Michal Hnati?; Juha Honkonen; Tomáš Lu?ivjanský

    2013-02-01T23:59:59.000Z

    Annihilation processes, where the reacting particles are influenced by some external advective field, are one of the simplest examples of nonlinear statistical systems. This type of processes can be observed in miscellaneous chemical, biological or physical systems. In low space dimensions usual description by means of kinetic rate equation is not sufficient and the effect of density fluctuations must be taken into ac- count. Using perturbative renormalization group we study the influ- ence of random velocity field on the kinetics of single-species annihila- tion reaction at and below its critical dimension $d_c = 2$. The advecting velocity field is modelled by the self-similar in space Gaussian variable finite correlated in time (Antonov-Kraichnan model). Effect of the compressibility of velocity field is taken into account and the model is analyzed near its critical dimension by means of three-parameter expansion in $\\epsilon$, $\\Delta$ and $\\eta$. Here $\\epsilon$ is the deviation from the Kolmogorov scaling, $\\Delta$ is the deviation from the (critical) space dimension 2 and {\\eta} is the deviation from the parabolic dispersion law. Depending on the value of these exponents and the value of compressiblity parameter {\\alpha}, the studied model can exhibit various asymptotic (long-time) regimes corresponding to the infrared (IR) fixed points of the renormalization group. The possible regimes are summarized and the decay rates for the mean particle number are calculated in the leading order of the perturbation theory.

  20. Compression part of Egan Hub facility`s expansion

    SciTech Connect (OSTI)

    NONE

    1997-11-01T23:59:59.000Z

    Egan Hub Partners, L.P. (EHP), a subsidiary of Market Hub Partners (MHP), is the owner and operator of the Egan Hub Partners gas storage facility located near the town of Evangeline in south Louisiana. Located on the Jennings salt dome, EHP provides high-deliverability (injection and/or withdrawal capabilities on demand) salt storage, giving its customers rapid response to market fluctuation and demand. In addition to long-term storage contracts, EHP offers natural gas hub services using interruptible storage entitlements and multiple pipeline interchange flexibility. Hub services include wheeling, parking, loaning and balancing. The EHP facility was put into service in September 1995. EHP just completed the installation of a fourth compressor unit. This is the second unit to be put in service at the facility this year and is identical to the previous one. Hanover Compression packaged both units which consist of a Caterpillar G-3616 engine (4,450 hp) and an Ariel JGC-6 compressor. The units are configured to accommodate the wide operating range encountered at a natural gas salt dome storage facility and are designed to operate with a suction range of 600--900 psi and a discharge range of 800--3,000 psi.