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Envera Variable Compression Ratio Engine
Charles Mendler
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
Eccentric crank variable compression ratio mechanism
Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)
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.
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
Some investigations in design of low cost variable compression ratio two stroke petrol engine
Srinivas, A; rao, P Venkateswar; Reddy, M Penchal
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...
The Use of Fuel Chemistry and Property Variations to Evaluate the Robustness of Variable Compression Ratio as a Control Method for Gasoline HCCI
Szybist, James P [ORNL; Bunting, Bruce G [ORNL
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.
Variable ratio regenerative braking device
Hoppie, Lyle O. (Birmingham, MI)
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.
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...
Prediction-Based Compression Ratio Boundaries for Medical Images
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
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 &...
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
Particle acceleration in thick parallel shocks with high compression ratio
Joni J. P. Virtanen; Rami Vainio
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.
The relation of octane number, compression ratio, and exhaust temperature in the gasoline engine
Jentsch, Donald George
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...
Variable valve timing in a homogenous charge compression ignition engine
Lawrence, Keith E.; Faletti, James J.; Funke, Steven J.; Maloney, Ronald P.
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.
Effects of operating conditions, compression ratio, and gasoline reformate on SI engine knock limits
Gerty, Michael D
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 ...
High compression ratio turbo gasoline engine operation using alcohol enhancement
Lewis, Raymond (Raymond A.)
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 ...
The Effects of Fuel Composition and Compression Ratio on Thermal Efficiency in an HCCI Engine
Szybist, James P [ORNL; Bunting, Bruce G [ORNL
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.
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...
Variable compression ratio device for internal combustion engine
Maloney, Ronald P.; Faletti, James J.
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.
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%...
Mesoscale flows in large aspect ratio simulations of turbulent compressible convection
F. Rincon; F. Lignieres; M. Rieutord
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.
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
Temporal variability of uranium concentrations and 234 activity ratios in the Mississippi river and its tributaries
conservatively under oxic conditions. As a consequence, the uranium concentration of seawater is relativelyTemporal variability of uranium concentrations and 234 U/238 U activity ratios in the Mississippi/238 U activity ratios and total dissolved uranium concentrations in the Lower Mississippi River at New
Control system and method for a power delivery system having a continuously variable ratio transmission
Frank, A.A.
A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine. 4 figs.
Control system and method for a power delivery system having a continuously variable ratio transmission
Frank, Andrew A. (1034 Hillside Ave., Madison, WI 53705)
A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for minimum fuel consumption. CVT ratio is controlled as a function of commanded power or torque and measured load, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristic for any load placed on the engine.
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
Validation of a blowby model using experimental results in motoring condition with the change of compression ratio and engine speed
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)
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)
Stellar population models of Lick indices with variable element abundance ratios
Daniel Thomas; Claudia Maraston; Ralf Bender
We provide the whole set of Lick indices from CN1 to TiO2 of Simple Stellar Population models with, for the first time, variable element abundance ratios, [alpha/Fe]=0.0, 0.3, 0.5, [alpha/Ca]=-0.1, 0.0, 0.2, 0.5, and [alpha/N]=-0.5, 0.0. The models cover ages between 1 and 15 Gyr, metallicities between 1/200 and 3.5 solar. Our models are free from the intrinsic alpha/Fe bias that was imposed by the Milky Way template stars up to now, hence they reflect well-defined alpha/Fe ratios at all metallicities. The models are calibrated with Milky Way globular clusters for which metallicities and alpha/Fe ratios are known from independent spectroscopy of individual stars. The metallicities that we derive from the Lick indices Mgb and Fe5270 are in excellent agreement with the metallicity scale by Zinn & West (1984), and we show that the latter provides total metallicity rather than iron abundance. We can reproduce the relatively strong CN-absorption features CN1 and CN2 of galactic globular clusters with models in which nitrogen is enhanced by a factor three. An enhancement of carbon, instead, would lead to serious inconsistencies with the indices Mg1 and C24668. The calcium sensitive index Ca4227 of globular clusters is well matched by our models with [Ca/Fe]= 0.3, including the metal-rich Bulge clusters NGC 6528 and NGC 6553. From our alpha/Fe enhanced models we infer that the index [MgFe] defined by Gonzalez (1993) is quite independent of alpha/Fe, but still slightly decreases with increasing alpha/Fe. We define a slight modification of this index that is completely independent of alpha/Fe and serves best as a tracer of total metallicity. Searching for blue indices that give similar information as Mgb and Fe, we find that CN1 and Fe4383 may be best suited to estimate alpha/Fe ratios of objects at redshifts z~1. (Abridged)
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...
Compressing bitmap indexes for faster search operations
Wu, Kesheng; Otoo, Ekow J.; Shoshani, Arie
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.
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
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
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.
Mechanical Compression Heat Pumps�
Apaloo, T. L.; Kawamura, K.; Matsuda, J.
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...
Net pay evaluation: a comparison of methods to estimate net pay and net-to-gross ratio using surrogate variables
Bouffin, Nicolas
purposes. These methods usually involve the use of cut-off values of one or more surrogate variables to discriminate non-reservoir from reservoir rocks. This study investigates statistical issues related to the selection of such cut-off values...
Dynamic control of a homogeneous charge compression ignition engine
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)
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.
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...
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...
Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)
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%.
Sandford, M.T. II; Handel, T.G.; Bradley, J.N.
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.
Sandford, M.T. II; Handel, T.G.; Bradley, J.N.
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.
Sandford, II, Maxwell T. (Los Alamos, NM); Handel, Theodore G. (Los Alamos, NM); Bradley, Jonathan N. (Los Alamos, NM)
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.
High efficiency coarse-grained customised dynamically reconfigurable architecture for digital image processing and compression technologies�
Zhao, Xin
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 ...
High load operation in a homogeneous charge compression ignition engine
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)
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
Chapter 22: Compressed Air Evaluation Protocol
Benton, N.
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.
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...
A New Approach for Fingerprint Image Compression
Mazieres, Bertrand
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.
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
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
Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung
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.
Compressed Air Supply Efficiency
Joseph, B.
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...
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 ...
Compressed Air Supply Efficiency�
Joseph, B.
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...
Consider Compressed Combustion
Crowther, R. H.
sharing systems employing gas turbines. Incentives for compressed combustion have been explored and are presented in this discussion....
Hildebrand, Richard J. (Edgemere, MD); Wozniak, John J. (Columbia, MD)
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.
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.
MULTISCALE RANDOM PROJECTIONS FOR COMPRESSIVE CLASSIFICATION Marco F. Duarte,r
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
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
Secondary compression of peat with or without surcharging
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)
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.
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
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...
Modeling Compressed Turbulence
Israel, Daniel M. [Los Alamos National Laboratory
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.
Beals, C.
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...
Seismic pore space compressibility and Gassmann`s relation
Mavko, G.; Mukerji, T. [Stanford Univ., CA (United States). Rock Physics Lab.] [Stanford Univ., CA (United States). Rock Physics Lab.
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.
Wavelet/scalar quantization compression standard for fingerprint images
Brislawn, C.M.
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.
MASe UCRL-15037 CONTINUOUSLY VARIABLE TRANSMISSIONS: THEORY AND...
Office of Scientific and Technical Information (OSTI)
transmission when operating in the power recirculation mode 20 Simple manual system to control the speed ratio of a variable V-belt continuously variable transmission 21 Schematic...
Compressive Rendering of Multidimensional Scenes
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
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...
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...
Random Weights Search in CompressedNeural Networks Using OverdeterminedPseudoinverse
Wilamowski, Bogdan Maciej
regions by variable tabu list size. Overvieu, of combination of neural network gradient search and TabuRandom Weights Search in CompressedNeural Networks Using OverdeterminedPseudoinverse Milos Manic is reduction of weight set. Second phase is gradient calculation on such compressed network. Search for weights
Compression Aware Physical Database Design
Kimura, Hideaki; Syamala, Manoj
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...
Interannual variability in tropospheric nitrous oxide
Thompson, R. L.
Observations of tropospheric N2O mixing ratio show significant variability on interannual timescales (0.2?ppb, 1 standard deviation). We found that interannual variability in N2O is weakly correlated with that in CFC-12 ...
Efficient Joins with Compressed Bitmap Indexes
Computational Research Division; Madduri, Kamesh; Wu, Kesheng
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.
Shock compression of precompressed deuterium
Armstrong, M R; Crowhurst, J C; Zaug, J M; Bastea, S; Goncharov, A F; Militzer, B
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.
Making Compressed Air System Decisions
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...
New Regenerative Cycle for Vapor Compression Refrigeration
Mark J. Bergander
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.
Streaming Compression of Hexahedral Meshes
Isenburg, M; Courbet, C
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.
Application specific compression : final report.
Melgaard, David Kennett; Byrne, Raymond Harry; Myers, Daniel S.; Harrison, Carol D.; Lee, David S.; Lewis, Phillip J.; Carlson, Jeffrey J.
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.
Data Compression with Prime Numbers
Gordon Chalmers
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.
Viscosity, entropy and the viscosity to entropy density ratio; how perfect is a nucleonic fluid?
Aram Z. Mekjian
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.
Energy-Optimized Lossless Compression: Rate-Variability Tradeoff
Wu, Yihong
is larger in this case. This motivates the problem of designing efficient compressors to minimize total Alto, CA 94304 Email: email@example.com Abstract--We pose the problem of energy energy consumption. Such energy-optimized compressors could prove useful for embedded systems
alvar variable compression: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
effects are positive and some are negative. In this work we provide a basis for an analysis of these effects and suggestions to overcome the negative implications in order to...
Some facts concerning ratios of random variables N. Papadatos
Papadatos, Nickos
)). (5) Applying (5) to g(t, w, i) = (wti , wt1-i ) we get, in view of (4), that (X, Y ) d = (Y, X), so
Gas turbine power plant with supersonic shock compression ramps
Lawlor, Shawn P. (Bellevue, WA); Novaresi, Mark A. (San Diego, CA); Cornelius, Charles C. (Kirkland, WA)
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.
The FBI compression standard for digitized fingerprint images
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)
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.
Efficient Joins with Compressed Bitmap Indexes
Madduri, Kamesh
compression is extremely e?cient for compressing bitmap indexescompression: There are however various approaches to extend the e?ectiveness of bitmap indexes
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,...
The decommodified security ratio
Paris-Sud XI, Universit� 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
Advances in compressible turbulent mixing
Dannevik, W.P.; Buckingham, A.C.; Leith, C.E. [eds.
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.
Best compression: Reciprocating or rotary?
Cahill, C.
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.
Polak, J.C.
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.
Compressed gas fuel storage system
Wozniak, John J. (Columbia, MD); Tiller, Dale B. (Lincoln, NE); Wienhold, Paul D. (Baltimore, MD); Hildebrand, Richard J. (Edgemere, MD)
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.
Compressed Air Audits using AIRMaster
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...
Evaluation of compression members with non-ideal end conditions
Marek, David Leslie
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...
Variable delivery, fixed displacement pump
Sommars, Mark F. (Sparland, IL)
A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.
The wavelet/scalar quantization compression standard for digital fingerprint images
Bradley, J.N.; Brislawn, C.M.
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.
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
Electron Pulse Compression with a Practical Reflectron Design for Ultrafast Electron Diffraction
Wang, Yihua
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.
Apparatus for measuring tensile and compressive properties of solid materials at cryogenic temperatures
Gonczy, John D. (Oaklawn, IL); Markley, Finley W. (St. Charles, IL); McCaw, William R. (Burr Ridge, IL); Niemann, Ralph C. (Downers Grove, IL)
An apparatus for evaluating the tensile and compressive properties of material samples at very low or cryogenic temperatures employs a stationary frame and a dewar mounted below the frame. A pair of coaxial cylindrical tubes extend downward towards the bottom of the dewar. A compressive or tensile load is generated hydraulically and is transmitted by the inner tube to the material sample. The material sample is located near the bottom of the dewar in a liquid refrigerant bath. The apparatus employs a displacement measuring device, such as a linear variable differential transformer, to measure the deformation of the material sample relative to the amount of compressive or tensile force applied to the sample.
Compressive behavior of fine sand.
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)
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.
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,...
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...
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
Image Compression by Back Propagation
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
Jeffrey Gutterman; A. J. Lasley
Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.
Compression of cooked freeze-dried carrots
Macphearson, Bruce Alan
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...
Robert Connon Smith
Cataclysmic variables are binary stars in which a relatively normal star is transferring mass to its compact companion. This interaction gives rise to a rich range of behaviour, of which the most noticeable are the outbursts that give the class its name. Novae belong to the class, as do the less well known dwarf novae and magnetic systems. Novae draw their energy from nuclear reactions, while dwarf novae rely on gravity to power their smaller eruptions. All the different classes of cataclysmic variable can be accommodated within a single framework and this article will describe the framework, review the properties of the main types of system and discuss models of the outbursts and of the long-term evolution.
Compressibility and strength of nanocrystalline tungsten boride under compression to 60GPa
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
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
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.
Mixed RL-Huffman Encoding for Power Reduction and Data Compression in Scan Test
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
Computation of Weakly-Compressible Highly-Viscous Polymeric Liquid Flows
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
Liquid piston gas compression James D. Van de Ven a,*, Perry Y. Li b,1
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
The impact of skull bone intensity on the quality of compressed CT neuro images
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
A Numerical Method for Two Phase Flow Consisting of Separate Compressible and
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
Compressed air energy storage system
Ahrens, Frederick W. (Naperville, IL); Kartsounes, George T. (Naperville, IL)
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.
Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons
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
An Efficient Technique for Text Compression
Azad, Md Abul Kalam; Ahmad, Shabbir; Kamruzzaman, S M
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...
Effect of Compressibility on the Annihilation Process
Michal Hnati?; Juha Honkonen; Tom� Lu?ivjansk�
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.
Industrial Compressed Air System Energy Efficiency Guidebook.
United States. Bonneville Power Administration.
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.
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...
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
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
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
A Compressed Air Reduction Program
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...
High ratio recirculating gas compressor
Weinbrecht, J.F.
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.
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.
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
Optimization Online - Compressed Sensing Off the Grid
Gongguo Tang
Sep 13, 2012 ... Compressed Sensing Off the Grid. Gongguo Tang(gtang5 ***at*** wisc.edu) Badri Narayan Bhaskar(bnbhaskar ***at*** wisc.edu) Parikshit�...
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...
Curran, Scott [ORNL; Briggs, Thomas E [ORNL; Cho, Kukwon [ORNL; Wagner, Robert M [ORNL
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.
A Numerical Study of Methods for Moist Atmospheric Flows: Compressible Equations
Duarte, Max; Balakrishnan, Kaushik; Bell, John B; Romps, David M
We investigate different numerical techniques for evolving moist atmospheric flows within a fully compressible framework. In the standard numerical approach, the choice of variables is motivated by those that remain invariant in dry adiabatic flow, phase transitions are treated as an external energy source, and the physically-irrelevant fast acoustic modes are decoupled during the numerical integration. For the purposes of this study, we consider the compressible Euler equations in terms of the primitive thermodynamic variables, namely density, momentum, and total energy of moist air, without any special numerical treatment of the fast acoustic dynamics. This allows us to incorporate consistent moist thermodynamic properties throughout the numerical solution, and to thoroughly investigate both the standard two-step splitting approach for moist atmospheric flows as well as a fully coupled technique based on the use of variables that are conserved in moist flows, i.e. total energy of moist air and total water c...
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
Defect Analysis of Vehicle Compressed Natural Gas
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
The Spatial Scaling Laws of Compressible Turbulence
Sun, Bohua
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}})\
Compressible fluid model for hydrodynamic lubrication cavitation
Sart, Remi
Compressible fluid model for hydrodynamic lubrication cavitation G. Bayada L. Chupin I.C.J. email@example.com 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
Revealing the potential of Compressed Earth Blocks : a visual narration
Rabie, Omar
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 ...
Wavelet compression for unsteady CFD data Oxford University Computing Laboratory
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
Compressed bitmap indices for efficient query processing
Wu, Kesheng; Otoo, Ekow; Shoshani, Arie
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.
Secure Compressed Reading in Smart Grids
Cai, Sheng; Chen, Minghua; Yan, Jianxin; Jaggi, Sidharth
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 ...
Quantum Data Compression of a Qubit Ensemble
Lee A. Rozema; Dylan H. Mahler; Alex Hayat; Peter S. Turner; Aephraim M. Steinberg
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.
Compression molding of aerogel microspheres
Pekala, R.W.; Hrubesh, L.W.
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.
Compression molding of aerogel microspheres
Pekala, Richard W. (Pleasant Hill, CA); Hrubesh, Lawrence W. (Pleasanton, CA)
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.
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...
High-Efficiency Clean Combustion Engine Designs for Compression...
High-Efficiency Clean Combustion Engine Designs for Compression Ignition Engines High-Efficiency Clean Combustion Engine Designs for Compression Ignition Engines Presentation from...
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...
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,...
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:...
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...
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...
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...
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)...
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...
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...
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...
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...
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...
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...
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...
DOE Announces Webinars on Compressed Natural Gas Infrastructure...
Compressed Natural Gas Infrastructure, an Advanced Rooftop Unit Campaign, and More DOE Announces Webinars on Compressed Natural Gas Infrastructure, an Advanced Rooftop Unit...
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...
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...
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...
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...
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...
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...
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...
Apparatus for measuring tensile and compressive properties of solid materials at cryogenic temperatures
Gonczy, J.D.; Markley, F.W.; McCaw, W.R.; Niemann, R.C.
An apparatus for evaluating the tensile and compressive properties of material samples at very low or cryogenic temperatures employs a stationary frame and a dewar mounted below the frame. A pair of coaxial cylindrical tubes extend downward towards the bottom of the dewar. A compressive or tensile load is generated hydraulically and is transmitted by the inner tube to the material sample. The material sample is located near the bottom of the dewar in a liquid refrigerant bath. The apparatus employs a displacement measuring device, such as a linear variable differential transformer, to measure the deformation of the material sample relative to the amount of compressive or tensile force applied to the sample. 7 figs.
Objective index of image fidelity for JPEG2000 compressed body CT images
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)
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.
Compressed Gas Safety for Experimental Fusion Facilities
Lee C. Cadwallader
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.
Compressed Gas Safety for Experimental Fusion Facilities
Cadwallader, L.C. [Idaho National Engineering and Environmental Laboratory (United States)
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.
Autoignition of toluene and benzene at elevated pressures in a rapid compression machine
Mittal, Gaurav; Sung, Chih-Jen [Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States)
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)
Nuclear Instruments and Methods in Physics Research A 577 (2007) 223230 Neutralized drift compression experiments with a
Gilson, Erik
.: +1 510 495 2616; fax: +1 510 486 5392. E-mail address: firstname.lastname@example.com (P.K. Roy). #12;ratio, the ratio compression experiments with a high-intensity ion beam P.K. Roya,�, 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
Moore, J. Jeffrey; Allison, Timothy; Evans, Neal; Moreland, Brian; Hernandez, Augusto; Day, Meera; Ridens, Brandon
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.
Shock compression profiles in ceramics
Grady, D.E.; Moody, R.L.
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.
PHELIX for flux compression studies
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
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.
Heat pump employing optimal refrigerant compressor for low pressure ratio applications
Ecker, Amir L. (Dallas, TX)
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.
Analysis of Arithmetic Coding for Data Compression
Howard, Paul G.; Vitter, Jeffrey Scott
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 ...
Compressed Index for Dictionary Matching (extended abstract)
Hon, Wing-Kai; Lam, Tak-Wah; Shah, Rahul; Siu-Lung, Tam; Vitter, Jeffrey Scott
the kth- order empirical entropy of T, and � 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...
Ramp Compression Experiments - a Sensitivity Study
Bastea, M; Reisman, D
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.
Compressed Air Load Reduction Approaches and Innovations
D'Antonio, M.; Epstein, G.; Moray, S.; Schmidt, C.
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...
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 &...
Wavelet compression of geodetic integral operators
Stuttgart, Universit�t
1 Wavelet compression of geodetic integral operators W. Keller Institute of Geodesy, Universit�t 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
An advanced vapor-compression desalination system�
Lara Ruiz, Jorge Horacio Juan
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...
Seneca Compressed Air Energy Storage (CAES) Project
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.
Compressing measurements in quantum dynamic parameter estimation
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 ...
Compression and Creep of Venice Lagoon Sands
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 ...
Dictionary Design for Distributed Compressive Sensing
Chen, Wei; Wassell, Ian J.; Rodrigues, Miguel R. D.
-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...
Compressed Indexes for Approximate String Matching
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,email@example.com Abstract. We revisit the problem of indexing a string S[1..n] to support searching all substrings
Exergy Analysis of Industrial Air Compression
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...
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
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.
Energy Efficiency in Compressed Air Systems�
Hingorani, A.; Pavlov, A.
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...
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
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
The Future of Image Compression William A. Pearlman
compact, higher power batteries would expand application scenarios for compression � Miniaturization
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
Paris-Sud XI, Universit� de
Wavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image Compression and MathematicalWavelet Based Color Image email@example.com Abstract One of the advantages of the Discrete Wavelet Transform (DWT) compared to Fourier Transform (e
DNA Compression Challenge Revisited: a Dynamic Programming Approach
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
Dynamic time expansion and compression using nonlinear waveguides
Findikoglu, Alp T. (Los Alamos, NM); Hahn, Sangkoo F. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)
Dynamic time expansion or compression of a small-amplitude input signal generated with an initial scale is performed using a nonlinear waveguide. A nonlinear waveguide having a variable refractive index is connected to a bias voltage source having a bias signal amplitude that is large relative to the input signal to vary the reflective index and concomitant speed of propagation of the nonlinear waveguide and an electrical circuit for applying the small-amplitude signal and the large amplitude bias signal simultaneously to the nonlinear waveguide. The large amplitude bias signal with the input signal alters the speed of propagation of the small-amplitude signal with time in the nonlinear waveguide to expand or contract the initial time scale of the small-amplitude input signal.
Dynamic Time Expansion and Compression Using Nonlinear Waveguides
Findikoglu, Alp T.; Hahn, Sangkoo F.; Jia, Quanxi
Dynamic time expansion or compression of a small amplitude input signal generated with an initial scale is performed using a nonlinear waveguide. A nonlinear waveguide having a variable refractive index is connected to a bias voltage source having a bias signal amplitude that is large relative to the input signal to vary the reflective index and concomitant speed of propagation of the nonlinear waveguide and an electrical circuit for applying the small amplitude signal and the large amplitude bias signal simultaneously to the nonlinear waveguide. The large amplitude bias signal with the input signal alters the speed of propagation of the small-amplitude signal with time in the nonlinear waveguide to expand or contract the initial time scale of the small-amplitude input signal.
Radiative Decay of Bubble Oscillations in a Compressible Fluid
A. M. Shapiro; M. I. Weinstein
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.
RESEARCH ARTICLE Development and characterization of a variable turbulence
Lieuwen, Timothy C.
(7):1037�1048, 2009), where variable blockage ratio slots are located upstream of a contoured nozzle. Vortical A Nozzle exit area E Power spectral density ReD Geometric Reynolds number Rel Turbulent Reynolds number SLRESEARCH ARTICLE Development and characterization of a variable turbulence generation system A
Weather-Corrected Performance Ratio
Dierauf, T.; Growitz, A.; Kurtz, S.; Cruz, J. L. B.; Riley, E.; Hansen, C.
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.
Fixed Block Compression Boosting in FM-Indexes
K�rkk�inen, Juha
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.
Performances of Multi-Level and Multi-Component Compressed Bitmap Indices
Wu, Kesheng; Stockinger, Kurt; Shoshani, Arie
Without compression, the index sizes monotonically decreaseprocessing cost. With compression, the index sizes no longermulti-component indexes without compression. Let C 1 , C
Improving Energy Efficiency of Compressed Air System Based on System Audit
Shanghai, Hongbo Qin; McKane, Aimee
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
Alternative Fuel Vehicles: The Case of Compressed Natural Gas (CNG) Vehicles in California Households
Abbanat, Brian A.
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
Hydrodynamic compressibility of high-strength ceramics
Grady, D.E.
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.
Compressed Air Systems Audits - Why? And How?
Kemp, H. L.
. 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...
Understanding the Basics of Compressed Air Systems
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...
Fast electron microscopy via compressive sensing
Larson, Kurt W; Anderson, Hyrum S; Wheeler, Jason W
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.
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
Conservation Theory Process Control Using Variable Frequency Drives
Myers, N. S.
name from the vari able DC voltage which the rectifier section pro duces. Variable DC voltage is required in order to produce controlled AC with the volts per hz ratio constant. To operate an AC motor over a speed range from 5-60 hz and still... be capable of producing con stant torque,the ratio: Volts ~ = Constant must be satisfied. The rectifier and inverter stages work in concert to produce variable voltage, variable frequency AC power. The linear relation ship between voltage and frequency...
Anisotropic Characterization of Asphalt Mixtures in Compression�
Zhang, Yuqing 1983-
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...
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...
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...
Massive-scale RDF Processing Using Compressed Bitmap Indexes
Madduri, Kamesh
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.
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...
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...
CO? compression for capture-enabled power systems
Suri, Rajat
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 ...
Compressing Social Networks The Minimum Logarithmic Arrangement Problem
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
Energy Efficiency in Compressed Air Systems
Hingorani, A.; Pavlov, A.
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...
Advanced Controls for Industrial Compressed Air Systems
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...
Cryo-compressed Hydrogen Storage. Tobias Brunner
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
Compression of Antiproton Clouds for Antihydrogen Trapping
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
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.
Technical Notes Compressive Sensing and Reconstruction
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
Distributed Compressed Sensing in Dynamic Networks
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
Regression Cubes with Lossless Compression and Aggregation
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
Asynchronous Compressive Radar , Samuel Palermo1
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
Georgia Tech Profiling Overconsolidation Ratio in
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
Blowing Ratio Effects on Film Cooling Effectiveness�
Liu, Kuo-Chun
. 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...
Summary of Compression Testing of U-10Mo
Nyberg, Eric A.; Joshi, Vineet V.; Lavender, Curt A.; Burkes, Douglas
The mechanical properties of depleted uranium plus 10 weight percent molybdenum alloy have been evaluated by high temperature compression testing.
Novel Spark Plugs Improve Energy Efficiency of Compressed Natural
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
PDM performance Test Results and Preliminary Analysis: Incompressible and Compressible Fluids
Dreesen, D.S.; Gruenhagan, E.; Cohen, J.C.; Moran, D.W.
Three, small diameter, Moineau, positive displacement (drilling) motors (PDMs) were dynamometer tested using water, air-water mist, air-water foam, and aerated water. The motors included (1) a 1.5-inch OD, single-lobe mud motor; (2) a 1.69-inch OD, 5:6 multi-lobe mud motor; and (3) a 1.75-inch OD, 5:6 multi-lobe air motor. This paper describes the test apparatus, procedures, data analysis, and results. Incompressible and compressible fluid performance are compared; linear performance, predicted by a positive displacement motor model, is identified where it occurs. Preliminary results and conclusions are (1) the performance of all three motors is accurately modeled using a two-variable, linear model for incompressible fluid and (2) the model was not successfully adapted to model compressible fluid performance.
Ashtekar's variables without spin
Thomas Schucker
Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.
Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns
Rutqvist, J.
compressed air energy storage technology by the hydraulicscale electric energy storage technologies. Compressed air
Experimental investigation of piston heat transfer under conventional diesel and reactivity-controlled compression ignition combustion regimes
Splitter, Derek A [ORNL; Hendricks, Terry Lee [Sandia National Laboratories (SNL); Ghandhi, Jaal B [University of Wisconsin
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.
Practical method and device for enhancing pulse contrast ratio for lasers and electron accelerators
Zhang, Shukui; Wilson, Guy
An apparatus and method for enhancing pulse contrast ratios for drive lasers and electron accelerators. The invention comprises a mechanical dual-shutter system wherein the shutters are placed sequentially in series in a laser beam path. Each shutter of the dual shutter system has an individually operated trigger for opening and closing the shutter. As the triggers are operated individually, the delay between opening and closing first shutter and opening and closing the second shutter is variable providing for variable differential time windows and enhancement of pulse contrast ratio.
A Well-Balanced Scheme For Two-Fluid Flows In Variable Cross-Section ducts
Paris-Sud XI, Université de
, ) p = p(, s, ), h = h(, s, ). (21) Then in these variables the sound speed c satisfies c2 = p = h. (22 of a mixture of two compressible fluids (a gas (1) and a liquid (2), for instance) in a cross-section duct
Compressive Sensing Based High Resolution Channel Estimation ...
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.
arXiv:cond-mat/0305430v119May2003 Shearing or Compressing a Soft Glass in 2D: Time-concentration superposition
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
Compression mode resonances in Zr-90
Youngblood, David H.; Lui, YW; John, B.; Tokimoto, Y.; Clark, HL; Chen, X.
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...
Compression of ground-motion data
Long, J.W.
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.
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)
Combined rankine and vapor compression cycles
Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.
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.
Abundance Ratios in Early-Type Galaxies
Reynier Peletier
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.
Rice, C Keith [ORNL; Abdelaziz, Omar [ORNL; Shrestha, Som S [ORNL
This paper uses a well-regarded, hardware based heat pump system model to investigate a two-stage economizing cycle for cold climate heat pump applications. The two-stage compression cycle has two variable-speed compressors. The high stage compressor was modelled using a compressor map, and the low stage compressor was experimentally studied using calorimeter testing. A single-stage heat pump system was modelled as the baseline. The system performance predictions are compared between the two-stage and single-stage systems. Special considerations for designing a cold climate heat pump are addressed at both the system and component levels.
Homogenous charge compression ignition engine having a cylinder including a high compression space
Agama, Jorge R.; Fiveland, Scott B.; Maloney, Ronald P.; Faletti, James J.; Clarke, John M.
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.
Ratio model serves suprathreshold color luminance discrimination
Mullen, Kathy T.
Ratio model serves suprathreshold color� luminance discrimination Marcel J. Sankeralli and Kathy T quadrants of the red� green/luminance and blue�yellow/luminance planes of cardinal color space. We showed model of suprathreshold color�luminance dis- crimination, in which discrimination depends on a ratio
High Transformer ratios in collinear wakefield accelerators.
Power, J. G.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanreykin, A.; Schoessow, P.; High Energy Physics; Euclid Techlabs, LLC
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.
Hewitt, Jacqueline H.
with independent measurements carried out at the same epoch (Biggs et al. 1999), lending confidence in a confidence intervals that are somewhat larger than those of Biggs et al., probably because we adopt a more in relation to the lens mass model of Biggs et al., our bestfit time delay implies a Hubble constant of H o
Accurate Prediction of the Ammonia Probes of a Variable Proton-to-Electron Mass Ratio
Owens, Alec; Thiel, Walter; �pirko, Vladimir
A comprehensive study of the mass sensitivity of the vibration-rotation-inversion transitions of $^{14}$NH$_3$, $^{15}$NH$_3$, $^{14}$ND$_3$, and $^{15}$ND$_3$ is carried out variationally using the TROVE approach. Variational calculations are robust and accurate, offering a new way to compute sensitivity coefficients. Particular attention is paid to the $\\Delta k=\\pm 3$ transitions between the accidentally coinciding rotation-inversion energy levels of the $\
Understanding Biomass Feedstock Variability
Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover
If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.
Understanding Biomass Feedstock Variability
Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover
If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.
Percutaneous Vertebroplasty for Osteoporotic Compression Fracture: Multivariate Study of Predictors of New Vertebral Body Fracture
Komemushi, Atsushi, E-mail: firstname.lastname@example.com; 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)
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.
Modeling ramp compression experiments using large-scale molecular dynamics simulation.
Mattsson, Thomas Kjell Rene; Desjarlais, Michael Paul; Grest, Gary Stephen; Templeton, Jeremy Alan; Thompson, Aidan Patrick; Jones, Reese E.; Zimmerman, Jonathan A.; Baskes, Michael I. (University of California, San Diego); Winey, J. Michael (Washington State University); Gupta, Yogendra Mohan (Washington State University); Lane, J. Matthew D.; Ditmire, Todd (University of Texas at Austin); Quevedo, Hernan J. (University of Texas at Austin)
Molecular dynamics simulation (MD) is an invaluable tool for studying problems sensitive to atomscale physics such as structural transitions, discontinuous interfaces, non-equilibrium dynamics, and elastic-plastic deformation. In order to apply this method to modeling of ramp-compression experiments, several challenges must be overcome: accuracy of interatomic potentials, length- and time-scales, and extraction of continuum quantities. We have completed a 3 year LDRD project with the goal of developing molecular dynamics simulation capabilities for modeling the response of materials to ramp compression. The techniques we have developed fall in to three categories (i) molecular dynamics methods (ii) interatomic potentials (iii) calculation of continuum variables. Highlights include the development of an accurate interatomic potential describing shock-melting of Beryllium, a scaling technique for modeling slow ramp compression experiments using fast ramp MD simulations, and a technique for extracting plastic strain from MD simulations. All of these methods have been implemented in Sandia's LAMMPS MD code, ensuring their widespread availability to dynamic materials research at Sandia and elsewhere.
International magnetic pulse compression workshop: (Proceedings)
Kirbie, H.C.; Newton, M.A.; Siemens, P.D.
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.
Low emissions compression ignited engine technology
Coleman, Gerald N. (Dunlap, IL); Kilkenny, Jonathan P. (Peoria, IL); Fluga, Eric C. (Dunlap, IL); Duffy, Kevin P. (East Peoria, IL)
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.
Coke cake behavior under compressive forces
Watakabe, S.; Takeda, T.; Itaya, H.; Suginobe, H.
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.
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
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
The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems
Guo, Jiquan; /SLAC
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.
Almond, P.; Kaplan, D.; Shine, E.
Measured distribution coefficients (K{sub d} values) for environmental contaminants provide input data for performance assessments (PA) that evaluate physical and chemical phenomena for release of radionuclides from wasteforms, degradation of engineered components and subsequent transport of radionuclides through environmental media. Research efforts at SRNL to study the effects of formulation and curing variability on the physiochemical properties of the saltstone wasteform produced at the Saltstone Disposal Facility (SDF) are ongoing and provide information for the PA and Saltstone Operations. Furthermore, the range and distribution of plutonium K{sub d} values in soils is not known. Knowledge of these parameters is needed to provide guidance for stochastic modeling in the PA. Under the current SRS liquid waste processing system, supernate from F & H Tank Farm tanks is processed to remove actinides and fission products, resulting in a low-curie Decontaminated Salt Solution (DSS). At the Saltstone Production Facility (SPF), DSS is mixed with premix, comprised of blast furnace slag (BFS), Class F fly ash (FA), and portland cement (OPC) to form a grout mixture. The fresh grout is subsequently placed in SDF vaults where it cures through hydration reactions to produce saltstone, a hardened monolithic waste form. Variation in saltstone composition and cure conditions of grout can affect the saltstone's physiochemical properties. Variations in properties may originate from variables in DSS, premix, and water to premix ratio, grout mixing, placing, and curing conditions including time and temperature (Harbour et al. 2007; Harbour et al. 2009). There are no previous studies reported in the literature regarding the range and distribution of K{sub d} values in cementitious materials. Presently, the Savannah River Site (SRS) estimate ranges and distributions of K{sub d} values based on measurements of K{sub d} values made in sandy SRS sediments (Kaplan 2010). The actual cementitious material K{sub d} values and solubility values differ from the sandy sediments. The K{sub d} value range and distribution currently used in the PA are estimated to range between 0.25*K{sub d} and 1.75*K{sub d}, where the minimum and maximum values of the ranges reflect the 95% confidence level for the mean K{sub d} value (Kaplan 2010). The objective of the research with cementitious materials was to measure the range and distribution of a monovalent (Cs) and I{sup -} (anion), divalent (Sr), and trivalent (Eu) ions for a variety of laboratory-prepared saltstone surrogate samples to establish a K{sub d} range other than that which is presently used in the PA. It has been observed in laboratory samples that cure temperature profiles can affect properties such as heat of hydration, permeability, porosity, compressive strength, and set time (Harbour et al. 2009). The intent was to identify a range and distribution that could be used by stochastic modelers for the PA. Furthermore, the intent was to replace the arbitrarily selected distributions based on geological sandy sediments and to base it on actual cementitious materials. The scope of this study did not include understanding saltstone sorption mechanisms responsible for increasing or decreasing sorption. Similar to the work with cementitious materials, the purpose of the Pu sediment K{sub d} dataset was not to attempt to understand through statistics how to better understand Pu sorption to sediments or to lower Pu K{sub d} variance. The sediment Pu K{sub d} data is included in this study because it is a key risk driver for the PAs on the SRS, and there is presently no direct studies of Pu variability in SRS soils. Instead the distribution of Pu sediment K{sub d} values was assumed to be similar to other cations, as presented by Kaplan (2010).
A New Compressive Imaging Camera Architecture using Optical-Domain Compression
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
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...
A Compressed Self-Index for Genomic Databases
Gagie, Travis; Nekrich, Yakov; Puglisi, Simon J
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.
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...
COMPRESSIVE SAMPLING VS. CONVENTIONAL IMAGING Jarvis Haupt and Robert Nowak
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
Saturable inductor and transformer structures for magnetic pulse compression
Birx, Daniel L. (Londonderry, NH); Reginato, Louis L. (Orinda, CA)
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.
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...
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...
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...
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...
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...
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...
Multilayer compressive seal for sealing in high temperature devices
Chou, Yeong-Shyung (Richland, WA); Stevenson, Jeffry W. (Richland, WA)
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.
VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater
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
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...
Fuel-Free Compressed-Air Energy Storage: Fuel-Free, Ubiquitous Compressed-Air Energy Storage and Power Conditioning
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.
Probabilistic Analysis of the Compressibility of Soils
Jung, Byoung C.
of surface loads or variable soil deposits. In current practice, the analysis to determine settlements is deterministic. It assumes that the soil profile at a site is uniform from location to location, and only allows limited consideration of the variations...
University of Arizona Compressed Air Energy Storage
Simmons, Joseph; Muralidharan, Krishna
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.
Compact wavefunctions from compressed imaginary time evolution
Jarrod R. McClean; Al�n Aspuru-Guzik
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.
Compression station key to Texas pipeline project
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.
Frequency extrapolation by nonconvex compressive sensing
Chartrand, Rick [Los Alamos National Laboratory; Sidky, Emil Y [UNIV OF CHICAGO; Pan, Xiaochaun [UNIV OF CHICAGO
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.
Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns
Rutqvist, J.
Williams, Compressed air energy storage: Theory, resources,for the compressed air energy storage technology by thefor compressed air energy storage power generation, Japan
The roles of depth varying mechanical properties and permeability of the deep boundary condition in confined compression of articular cartilage
Lee, John J.
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,
Hydro-mechanical behavior of Municipal Solid Waste subject to leachate recirculation in a large-scale compression reactor cell
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: firstname.lastname@example.com; Gourc, Jean-Pierre [Laboratoire LIRIGM - Maison des Geosciences, 1381, rue de la piscine 38400 Saint-Martin d'Heres (France)]. E-mail: email@example.com
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.
Simple lossless and near-lossless waveform compression Tony Robinson
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
Mesh Geometry Compression for Mobile Graphics Jongseok Lee
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 email@example.com Sungyul--This paper presents a compression scheme for mesh geometry, which is suitable for mobile graphics. The main
A PARADIGM FOR TIME-PERIODIC SOUND WAVE PROPAGATION IN THE COMPRESSIBLE EULER EQUATIONS BLAKE consistent with time-periodic sound wave propagation in the 3 �? 3 nonlinear compressible Euler equations description of shock-free waves that propagate through an oscillating entropy field without breaking or dis
Lossless Wavelet Based Image Compression with Adaptive 2D Decomposition
Lossless Wavelet Based Image Compression with Adaptive 2D Decomposition Manfred Kopp firstname.lastname@example.com 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
Techno-economic Performance Evaluation of Compressed Air
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
Recovery of partially occluded objects by applying compressive Fresnel holography
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
Homogeneous Charge Compression Ignition: Formulation Effect of a Diesel Fuel
Paris-Sud XI, Universit� 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
Compressed Gas Cylinder Safety I. Background. Due to the nature
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
Simplified Compression of Redundancy Free Trellis Sections in Turbo Decoder
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
Variable nonlinear resistances
Howard, James Edgar
VARIETAL". NONLINEAR RESIS'IANCES A Thes1s JA'. 4ES EDGAR HOWARD as to style and content by Head Department January 1955 LIBRARY A 4 IS COLLEGE PF TEXAS VARIABLE NONLINEAR RESISTANCES A Thesis By JAMES EDGAR HOWARD Submitted...
Vector Boson Fusion Higgs Production at the LHC - Mass Variables
Dan Green
There exist substantial backgrounds to the vector boson fusion production of Higgs at the LHC. Mass variables are studied which may alleviate the need to assume a spin zero WW resonance in order to achieve a sufficient signal to noise ratio in the two jet plus two lepton and missing energy final state.
Video compression with 1-D directional transforms in H.264/AVC
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 ...
Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about Uncertainty
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
Coding for Transmission Coding for Compression Bonus Section CMPSCI 240: Reasoning about Uncertainty
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
Vacuum/Compression Valving (VCV) Using Parrafin-Wax on a Centrifugal Microfluidic CD Platform
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)
Correlation and image compression for limited-bandwidth CCD.
Thompson, Douglas G.
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.
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)
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.
Combustion dynamics in steady compressible flows
S. Berti; D. Vergni; A. Vulpiani
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.
Seneca Compressed Air Energy Storage (CAES) Project
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.
Progressive Compression of Volumetric Subdivision Meshes
Laney, D; Pascucci, V
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.
Quantum Bootstrapping via Compressed Quantum Hamiltonian Learning
Nathan Wiebe; Christopher Granade; David G. Cory
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.
Shock compression of low-density foams
Holmes, N.C.
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.
Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System
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.
Radioactive anomaly discrimination from spectral ratios
Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements
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.
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...
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...
A Decision-Based Analysis of Compressed Air Usage Patterns in Automotive Manufacturing
Yuan, Chris; Zhang, Teresa; Rangarajan, Arvind; Dornfeld, David; Ziemba, Bill; Whitbeck, Rod
Air Usage Patterns in Automotive Manufacturing Chris Y. Yuanper vehicle built from automotive manufacturing facilities,2004). Compressed Air in Automotive Manufacturing Compressed
SU-E-J-48: Development of An Abdominal Compression Device for Respiratory Correlated Radiation Therapy
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)
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.
Bourgeois, P.M.; Reger, R.J.
A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.
Sartin, Marvin; Sammons, Ray
)OC lAL45.7 173 1. 1224 Texas Agricultural Extension Service The Texas A&M University System Daniel C. Pfannstiel,Director colleg e Station, Texas / f , ' '~ :';,; ,,: ''': ~ " k , -~. _Variable _Crop Share _Leases ... Marvin... Sartin and Ray Sammons* Renting or leasing farmland is part of many modern farming operations and increases average farm size in U. S. agriculture. Economies of size are vitally import ant to farm operations as they strive to cope with the continuous...
Variable Frequency Pump Drives
Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.
. In a conventional pump and driver arrangement (for example, a centrifugal pump coupled to an AC induction motor'with no speed control provision), the motor runs at. a constant speed, which is determined by the incoming line frequency, and the pump... when it is needed. LONG RANGE DESIGN TRENDS The growing use of variable-frequency electric motor drives will permit the integration of 60 and 50 cycle pump lines. One important concern for future improvements is the growing possibility...
Fission Product Ratios as Treaty Monitoring Discriminants
Miley, Harry S.; Bowyer, Ted W.; Greenwood, Lawrence R.; Arthur, Richard J.
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�.
Viscosity to entropy ratio at extremality
Sayan K. Chakrabarti; Sachin Jain; Sudipta Mukherji
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.
Ratio method of measuring $w$ boson mass
Guo, Feng; /SUNY, Stony Brook
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.
Kusoglu, Ahmet; Weber, Adam; Jiang, Ruichin; Gittleman, Craig
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.
Hydrogen isotopic variability in leaf waxes among terrestrial and aquatic plants around Blood Pond, Massachusetts (USA)
Massachusetts at Amherst, University of
Hydrogen isotopic variability in leaf waxes among terrestrial and aquatic plants around Blood Pond interpretation of the hydrogen isotope ratios of plant leaf waxes extracted from sediments requires a thor- ough at a single site to determine how leaf wax hydro- gen isotope (D/H) ratios differ in different plant types
Variable Camshaft Timing Engine Control A. G. Stefanopoulou, J. S. Freudenberg, J. W. Grizzle
Grizzle, Jessy W.
| Multivariable Feedback Control, Air-to-Fuel Ratio, Emissions, Pollution Control, Internal Combustion Engines. I of Michigan an internal combustion engine to reduce feedgas emis- sions, regulate air-to-fuel ratio A. For the variable cam timing engine, issue i arises from the fact that minimization of feedgas emissions, smooth eng
Compression of solid nitromethane to 15 GPa at 298 K
Yarger, F.L.; Olinger, B.
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.
Stresses resulting from compression of bulk cotton lint fibers
Chimbombi, Ezekiel Maswe
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...
Statistical issues in Mendelian randomization: use of genetic instrumental variables for assessing causal associations
Burgess, Stephen
HWE Hardy�Weinberg equilibrium I(L)OR individual (log) odds ratio IL6 interleukin-6 IPD individual participant data IV instrumental variable LIML limited information maximum likelihood LD linkage disequilibrium LDL-C low-density lipoprotein cholesterol... (L)OR marginal (log) odds ratio P(L)OR population (log) odds ratio RCT randomized controlled trial SE standard error (G)SMM (generalized) structural mean model SNP single nucleotide polymorphism Abbreviations for the various studies in the CCGC are given...
Improved Grammar-Based Compressed Indexes
Claude, Francisco
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.
Analytical bunch compression studies for FLUTE
Schreck, M
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...
Blowing Ratio Effects on Film Cooling Effectiveness
Liu, Kuo-Chun
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...
aspect ratio wings: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratios numerical: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio microstructuring: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
average aspect ratios: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio tori: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio ion: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio su-8: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio micro: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio domains: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio electrodes: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
aspect ratio plasmas: Topics by E-print Network
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efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern Texas A&M University - TxSpace Summary: ratios on five-spot and...
Double-periodic blue variables in the Magellanic Clouds
R. E. Mennickent; G. Pietrzynski; M. Diaz; W. Gieren
We report the discovery, based on an inspection of the OGLE-II database, of a group of blue variables in the Magellanic Clouds showing simultaneously two kinds of photometric variability: a short-term cyclic variability with typical amplitude $\\Delta I \\sim$ 0.05 mag and period $P_{1}$ between 4 and 16 days and a sinusoidal, long-term cyclic oscillation with much larger amplitude $\\Delta I \\sim$ 0.2 mag with period $P_{2}$ in the range of 150-1000 days. We find that both periods seems to be coupled through the relationship $P_{2}$ = 35.2 $\\pm$ 0.8 $P_{1}$. In general, the short term variability is reminiscent of those shown by Algol-type binaries. We propose that the long-term oscillation could arise in the precession of a elliptical disc fed by a Roche-lobe filling companion in a low mass ratio Algol system.
Fuel effects in homogeneous charge compression ignition (HCCI) engines
Angelos, John P. (John Phillip)
Homogenous-charge, compression-ignition (HCCI) combustion is a new method of burning fuel in internal combustion (IC) engines. In an HCCI engine, the fuel and air are premixed prior to combustion, like in a spark-ignition ...
Global Inference for Sentence Compression: An Integer Linear Programming Approach�
Clarke, James
In this thesis we develop models for sentence compression. This text rewriting task has recently attracted a lot of attention due to its relevance for applications (e.g., summarisation) and simple formulation by means ...
Energy efficiency improvements in Chinese compressed air systems
McKane, Aimee; Li, Li; Li, Yuqi; Taranto, T.
system pressure problem because VSD compressors are able toproblems, the enterprise should first consider whether the existing array of compressorsproblems When enterprises focus their attention on their compressed air system, it is mainly on the compressors.
Weak-strong clustering transition in renewing compressible flows
Ajinkya Dhanagare; Stefano Musacchio; Dario Vincenzi
We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.
Algorithms for transform selection in multiple-transform video compression
Cai, Xun, S.M. Massachusetts Institute of Technology
Selecting proper transforms for video compression has been based on the rate-distortion criterion. Transforms that appear reasonable are incorporated into a video coding system and their performance is evaluated. This ...
Copper laser modulator driving assembly including a magnetic compression laser
Cook, Edward G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Ball, Don G. (Livermore, CA)
A laser modulator (10) having a low voltage assembly (12) with a plurality of low voltage modules (14) with first stage magnetic compression circuits (20) and magnetic assist inductors (28) with a common core (91), such that timing of the first stage magnetic switches (30b) is thereby synchronized. A bipolar second stage of magnetic compression (42) is coupled to the low voltage modules (14) through a bipolar pulse transformer (36) and a third stage of magnetic compression (44) is directly coupled to the second stage of magnetic compression (42). The low voltage assembly (12) includes pressurized boxes (117) for improving voltage standoff between the primary winding assemblies (34) and secondary winding (40) contained therein.
Pre-In-Plant Training Webinar (Compressed Air)
Broader source: Energy.gov [DOE]
This pre-In-Plant training webinar for the Better Plants Program covers the basics of finding energy savings in Compressed Air systems and introduces the AIRMaster+ software tool.
Workshop Agenda: Compressed Natural Gas and Hydrogen Fuels, Lesssons...
Broader source: Energy.gov (indexed) [DOE]
U. S. Department of Transportation and U.S. Department of Energy Compressed Natural Gas and Hydrogen Fuels: Lessons Learned for the Safe Deployment of Vehicles December 10-11,...
Outphasing Energy Recovery Amplifier With Resistance Compression for Improved Efficiency
Godoy, Philip Andrew
We describe a new outphasing energy recovery amplifier (OPERA) which replaces the isolation resistor in the conventional matched combiner with a resistance-compressed rectifier for improved efficiency. The rectifier recovers ...
Compressibility of Nuclear Matter from Shell Effects in Nuclei
M. M. Sharma
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.
A Space-Charge-Neutralizing Plasma for Beam Drift Compression
Roy, P.K.
beam drift compression P. K. Roy , P. A. Seidl , A. Anders ,45, 131 (2005). [3] P. K. Roy et al. , NIMA 544, 225 (the PAC05, p.4006. [10] P. K. Roy et al. , PRL, 95, (2005),
Representation and compression of multidimensional piecewise functions using surflets
Chandrasekaran, Venkat
We study the representation, approximation, and compression of functions in M dimensions that consist of constant or smooth regions separated by smooth (M-1)-dimensional discontinuities. Examples include images containing ...
Statistical Models for Images: Compression, Restoration and Synthesis
Simoncelli, Eero
/or nonlinear transfor� mations, into statistically independent components. The classical approach, and the Sloan Center for Theoretical Neurobiology at NYU. 1. Wavelet Marginal Statistical Model Recently, multiStatistical Models for Images: Compression, Restoration and Synthesis Eero P. Simoncelli Center
Business Case for Compressed Natural Gas in Municipal Fleets
Johnson, C.
This report describes how NREL used the CNG Vehicle and Infrastructure Cash-Flow Evaluation (VICE) model to establish guidance for fleets making decisions about using compressed natural gas.
Weak-strong clustering transition in renewing compressible flows
Dhanagare, Ajinkya; Vincenzi, Dario
We investigate the statistical properties of Lagrangian tracers transported by a time-correlated compressible renewing flow. We show that the preferential sampling of the phase space performed by tracers yields significant differences between the Lagrangian statistics and its Eulerian counterpart. In particular, the effective compressibility experienced by tracers has a non-trivial dependence on the time correlation of the flow. We examine the consequence of this phenomenon on the clustering of tracers, focusing on the transition from the weak- to the strong-clustering regime. We find that the critical compressibility at which the transition occurs is minimum when the time correlation of the flow is of the order of the typical eddy turnover time. Further, we demonstrate that the clustering properties in time-correlated compressible flows are non-universal and are strongly influenced by the spatio-temporal structure of the velocity field.
Grid adaptation for functional outputs of compressible flow simulations
Venditti, David Anthony, 1973-
An error correction and grid adaptive method is presented for improving the accuracy of functional outputs of compressible flow simulations. The procedure is based on an adjoint formulation in which the estimated error in ...
Mission Design for Compressive Sensing with Mobile Robots
Hummel, Robert
This paper considers mission design strategies for mobile robots whose task is to perform spatial sampling of a static environmental field, in the framework of compressive sensing. According to this theory, we can reconstruct ...
of the thermal compression process. However, many applications either do not have adequate waste heat, or the waste heat is difficult to access economically. In these cases, traditional fuels can be used to provide
The Many Faces of a Compressed Air Audit
Kemp, H. L.
with independent compressed air consultant organizations. Energy Audits Supplied by DOE-Sponsored University Students University students led by their instructors as part of their training perform these studies. Often the reports are accurate about...Air Power USA, Inc. PO Box 292 Pickerington, OH 43147 740 862-4112 740 862-8464 (Fax) www.airpowerusainc.com THE MANY FACES OF A COMPRESSED AIR AUDIT Industrial Energy Technology Conference May 9-12, 2006 New Orleans, LA Today...
Two-phase compressibility factors for retrograde gases
Rayes, Daniel George
of a liquid phase. Gas compressibility factors are used in the gas material balance equations. These equations are used to estimate initial gas in place and reserves. Normally gas compressibility factors are used when a reservoir fluid depletion.... 0 on a material balance plot. Dake's equation has limited usefulness because the initial gas in place G is an unknown in the field. Also note that Gp at the abandonment pressure is the ultimate reserves of the reservoir. We can also derive...
Optimized Node Selection for Compressive Sleeping Wireless Sensor Networks
Chen, Wei; Wassell, Ian J.
1Optimized Node Selection for Compressive Sleeping Wireless Sensor Networks Wei Chen, Member, IEEE, and Ian J. Wassell Abstract�In this paper, we propose an active node selection framework for compressive sleeping wireless sensor networks (WSNs... development oftechnologies in sensing, computing and communication has made it possible to employ wireless sensor networks (WSNs) to continuously monitor physical phenomena in a variety of applications, for example air quality monitoring, wildlife tracking...
Compression induced delamination in a unidirectional graphite/epoxy composite�
Earley, John W.
December 1981 Major Subject: Civil Engineering COMPRESSION INDUCED DELAMINATION IN A UNIDIRECTIONAL GRAPHITE/EPOXY COMPOSITE A Thesis by JOHN W. EARLEY Approved as to style and content by: (K. L. Jerina, Chairman) (R, A. Schape y', MemP ) W. L.... Bradley, Me er Il. 8 0 1d, O. pa t~tH d December 1981 ABSTRACT Compression Induced Delamination in a Unidirectional Graphite/Epoxy Composite (December 1981) John William Earley, B. S. Aeronautical Engineering California Polytechnic State University...
Efficiency of compressed-air systems. Final report
Not Available
The program undertaken by this contract is intended to quantify the current state of knowledge in American industry concerning the energy efficient design and operation of industrial compressed air systems and system components. Since there is no standard reference for designers and operators of compressed air systems which provides guidelines for maximizing the energy efficiency of these systems, a major product of this contract was the preparation of a guidebook for this purpose.
The effect of neutralization on compressive strength of stabilized phosphogypsum�
Yung, Chung Che
36 38 38 49 CONCLUSIONS AND RECQMMENDATIQNS 73 ' REFERENCES . APPENDIX A. APPENDIX B. APPENDIX C. APPENDIX D. IAFIQRATORY PROCEDURES FOR DETERMINING CaO CONTENT IN FLY ASH ~ ~ ~ DATA FROM PHASE I ~ ~ ~ IABORATORY PROCEDURES... . of neutralization using calcium hydroxide of neutralization using reclaimed fly ash 41 45 46 47 48 13 14 15 Three&ay unconf ined compressive strength versus phosphogypsum pB Seven-day unconfined compressive strength versus phosphogypsum pH Twentymight...
Correction of Wall Adhesion Effects in the Centrifugal Compression of Strong Colloidal Gels
Richard Buscall; Daniel R. Lester
Several methods for measuring the compressive strength of strong particulate gels are available, including the centrifuge method, whereby the strength as a function of volume-fraction is obtained parametrically from the dependence of equilibrium sediment height upon acceleration. The analysis used conventionally due to Buscall & White (1987) ignores the possibility that the particulate network might adhere to the walls of the centrifuge tube, even though many types of cohesive particulate gel can be expected to. The neglect of adhesion is justifiable when the ratio of the shear to compressive strength is small, which it can be for many systems away from the gel-point, but never very near it. The errors arising from neglect of adhesion are investigated theoretically and quantified by synthesising equilibrium sediment height versus acceleration data for various degrees of adhesion and then analysing them in the conventional manner. Approximate correction factors suggested by dimensionless analysis are then tested. The errors introduced by certain other approximations made routinely in order to render the data-inversion practicable are analysed too. For example, it shown that the error introduced by treating the acceleration vector as approximately one-dimensional is minuscule for typical centrifuge dimensions, whereas making this assumption renders the data inversion tractable.
Compression-induced stacking fault tetrahedra around He bubbles in Al
Shao, Jian-Li, E-mail: email@example.com; Wang, Pei; He, An-Min [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)
Classic molecular dynamics methods are used to simulate the uniform compression process of the fcc Al containing He bubbles. The formation of stacking fault tetrahedra (SFTs) during the collapse of He bubbles is found, and their dependence on the initial He bubble size (0.6�6?nm in diameter) is presented. Our simulations indicate only elastic deformation in the samples for the He bubble size not more than 2?nm. Instead, increasing the He bubble size, we detect several small SFTs forming on the surface of the He bubble (3?nm), as well as the two intercrossed SFTs around the He bubbles (4�6?nm). All these SFTs are observed to be stable under further compression, though there may appear some SF networks outside the SFTs (5�6?nm). Furthermore, the dynamic analysis on the SFTs shows that the yield pressure keeps a near-linear increase with the initial He bubble pressure, and the potential energy of Al atoms inside the SFTs is lower than outside because of their gliding inwards. In addition, the pressure increments of 2�6?nm He bubbles with strain are less than that of Al, which just provides the opportunity for the He bubble collapse and the SFTs formation. Note that the current work only focuses on the case that the number ratio between He atoms and Al vacancies is 1:1.
A correlation for the coefficient of isothermal compressibility of black oil at pressures below the bubble point
Villena Lanzi, Alejandro J
differential liberation and separator test data of black oil samples from 260 worldwide well locations. The data base consisted of values of isothermal compressibility, stock-tank oil gravity, surface gas gravity, total solution gas-oil ratio, and reservoir... Bubble Point Pressure, pb Surface Gas Specific Gravity, yg 2, 500 31. 0 x 10 to 6600 x 10 psi 1. 5 to 1947 scf/STB 6. 0 to 52. 0 'API 78. 0 to 330. 0 'F 500. 0 to 5300. 0 psig 763. 0 to 5300. 0 psig 0. 58 to 1. 2 Bod ~ relative oil volume...
SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) 2013
Gordon Rueff; Lyle Roybal; Denis Vollmer
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.
System using data compression and hashing adapted for use for multimedia encryption
Coffland, Douglas R. (Livermore, CA)
A system and method is disclosed for multimedia encryption. Within the system of the present invention, a data compression module receives and compresses a media signal into a compressed data stream. A data acquisition module receives and selects a set of data from the compressed data stream. And, a hashing module receives and hashes the set of data into a keyword. The method of the present invention includes the steps of compressing a media signal into a compressed data stream; selecting a set of data from the compressed data stream; and hashing the set of data into a keyword.
Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities
Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)
An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.
Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation
Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.
The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.
Selective document image data compression technique
Fu, C.Y.; Petrich, L.I.
A method of storing information from filled-in form-documents comprises extracting the unique user information in the foreground from the document form information in the background. The contrast of the pixels is enhanced by a gamma correction on an image array, and then the color value of each of pixel is enhanced. The color pixels lying on edges of an image are converted to black and an adjacent pixel is converted to white. The distance between black pixels and other pixels in the array is determined, and a filled-edge array of pixels is created. User information is then converted to a two-color format by creating a first two-color image of the scanned image by converting all pixels darker than a threshold color value to black. All the pixels that are lighter than the threshold color value to white. Then a second two-color image of the filled-edge file is generated by converting all pixels darker than a second threshold value to black and all pixels lighter than the second threshold color value to white. The first two-color image and the second two-color image are then combined and filtered to smooth the edges of the image. The image may be compressed with a unique Huffman coding table for that image. The image file is also decimated to create a decimated-image file which can later be interpolated back to produce a reconstructed image file using a bilinear interpolation kernel. 10 figs.
Commissioning of helium compression system for the 12 GeV refrigerator
Knudsen, Peter N. [JLAB; Ganni, Venkatarao [JLAB; Dixon, Kelly D. [JLAB; Norton, Robert O. [JLAB; Creel, Jonathan D. [JLAB; Arenius, Dana M. [JLAb
The compressor system used for the Jefferson Lab (JLab) 12 GeV upgrade, also known as the CHL-2 compressor system, incorporates many design changes to the typical compressor skid design to improve the efficiency, reliability and maintainability from previous systems. These include a considerably smaller bulk oil separator design that does not use coalescing elements/media, automated control of cooling oil injection based on the helium discharge temperature, a helium after-cooler design that is designed for and promotes coalescing of residual oil and a variable speed bearing oil pump to reduce oil bypass. The CHL-2 helium compression system has five compressors configured with four pressure levels that supports the three pressure levels in the cold box. This paper will briefly review several of these improvements and discuss some of the recent commissioning results.
Modeling added compressibility of porosity and the thermomechanical response of wet porous rock
Rubin, M.B.; Elata, D.; Attia, A.V.
This paper concerned with modeling the response of a porous brittle solid whose pores may be dry or partially filled with fluid. A form for the Helmholtz free energy is proposed which incorporated known Mie-Grueneisen constitutive equations for the nonporous solid and for the fluid, and which uses an Eilnstein formulation with variable specific heat. In addition, a functional form for porosity is postulated which porous rock. Restrictions on constitutive assumptions for the composite of porous solid ad fluid are obtained which ensure thermodynamic consistency. Examples show that although the added compressibility of porosity is determined by fitting data for dry Mt. Helen Tuff, the predicted responses of saturated and partially saturated tuff agree well with experimental data.
Compressed Air Energy Savings: SAV-AIR Monitor and Control System and the PNW Compressed Air Challenge
Anderson, K. J.; Annen, B.; Scott, S.
year in compressed air energy costs. Their system included three older oil-flooded screw compressors two 25-horsepower (HP) and one 75 -HP. Although 100-HP ofcompressor was running continuously, it was having trouble providing enough air... such as improperly installed or leaking distribution lines, outdated or inadequate controls, and excess compressor capacity. But efficiency improvements and speed controls could save over [7%. In the Pacific Northwest (PNW) compressed air systems consumed 4...
Energy recovery during expansion of compressed gas using power plant low-quality heat sources
Ochs, Thomas L. (Albany, OR); O'Connor, William K. (Lebanon, OR)
A method of recovering energy from a cool compressed gas, compressed liquid, vapor, or supercritical fluid is disclosed which includes incrementally expanding the compressed gas, compressed liquid, vapor, or supercritical fluid through a plurality of expansion engines and heating the gas, vapor, compressed liquid, or supercritical fluid entering at least one of the expansion engines with a low quality heat source. Expansion engines such as turbines and multiple expansions with heating are disclosed.
Implications of Fast Reactor Transuranic Conversion Ratio
Steven J. Piet; Edward A. Hoffman; Samuel E. Bays
Theoretically, the transuranic conversion ratio (CR), i.e. the transuranic production divided by transuranic destruction, in a fast reactor can range from near zero to about 1.9, which is the average neutron yield from Pu239 minus 1. In practice, the possible range will be somewhat less. We have studied the implications of transuranic conversion ratio of 0.0 to 1.7 using the fresh and discharge fuel compositions calculated elsewhere. The corresponding fissile breeding ratio ranges from 0.2 to 1.6. The cases below CR=1 (�burners�) do not have blankets; the cases above CR=1 (�breeders�) have breeding blankets. The burnup was allowed to float while holding the maximum fluence to the cladding constant. We graph the fuel burnup and composition change. As a function of transuranic conversion ratio, we calculate and graph the heat, gamma, and neutron emission of fresh fuel; whether the material is �attractive� for direct weapon use using published criteria; the uranium utilization and rate of consumption of natural uranium; and the long-term radiotoxicity after fuel discharge. For context, other cases and analyses are included, primarily once-through light water reactor (LWR) uranium oxide fuel at 51 MWth-day/kg-iHM burnup (UOX-51). For CR<1, the heat, gamma, and neutron emission increase as material is recycled. The uranium utilization is at or below 1%, just as it is in thermal reactors as both types of reactors require continuing fissile support. For CR>1, heat, gamma, and neutron emission decrease with recycling. The uranium utilization exceeds 1%, especially as all the transuranic elements are recycled. exceeds 1%, especially as all the transuranic elements are recycled. At the system equilibrium, heat and gamma vary by somewhat over an order of magnitude as a function of CR. Isotopes that dominate heat and gamma emission are scattered throughout the actinide chain, so the modest impact of CR is unsurprising. Neutron emitters are preferentially found among the higher actinides, so the neutron emission varies much stronger with CR, about three orders of magnitude.
High aspect ratio, remote controlled pumping assembly
Brown, Steve B. (Livermore, CA); Milanovich, Fred P. (Lafayette, CA)
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.
Energy Balance Bowen Ratio Station (EBBR) Handbook
Cook, DR
The energy balance Bowen ratio (EBBR) system produces 30-minute estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity (RH). Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.
Meteorological Effects on Air/Fuel Ratio
Ferri, J. L.
) where subscript 1 indicates at condition 1 and subsc 1pt 2 Indicates at condition 2. Solving for E gives 2 100. (E . 13) Example 1 A furnace with a pressure type ratio control sys~em is calibrated at 10% excess air with 30 of air. If the air... of ... 30 of ... 460? 590 oR Substituting in Equation 13 and solving for E gives 2 E = (100 ... 10) (:;~)II, - 100 = 3.3% excess ir. 2 If the furnace had been calibrated to 10% excess air with iOO of air, the % excess air with 30 of air would bJI 590 II...
High aspect ratio, remote controlled pumping assembly
Brown, S.B.; Milanovich, F.P.
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.
Three-dimensional evaluation of the compression and recovery behavior in a flexible graphite sheet by synchrotron radiation microtomography
Kobayashi, M., E-mail: firstname.lastname@example.com [Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, AICHI 441-8580 (Japan); Toda, H. [Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, AICHI 441-8580 (Japan); Takeuchi, A.; Uesugi, K.; Suzuki, Y. [Japan Synchrotron Radiation Research Institute, Sayo-gun, HYOGO 679-5198 (Japan)
The compression and unloading behavior of flexible graphite sheets was investigated using synchrotron radiation microtomography with 1 {mu}m voxel size. The recovery ratio of the flexible graphite sheet was measured accurately by in-situ observation. The three-dimensional strain distribution in the interior of the specimen was obtained using the microstructural tracking method. The inner strain distribution with micrometer scale indicated inhomogeneous deformation. The microstructural tracking analysis revealed that deformation units exist in the flexible graphite sheet. The units seem to deform, affecting the neighboring units with each other. The units had a similar size and shape with compacted exfoliated graphite worms that constitute the flexible graphite sheet. Microscopic deformations during compression and unloading are surely affected by the microstructure of the sheet. Highlights: Black-Right-Pointing-Pointer The compression and recovery behavior was investigated using microtomography. Black-Right-Pointing-Pointer The tracking analysis revealed that deformation units exist in the specimen. Black-Right-Pointing-Pointer Each unit deforms in relation to the neighboring unit.
Ratios of heavy hadron semileptonic decay rates
Michael Gronau; Jonathan L. Rosner
Ratios of charmed meson and baryon semileptonic decay rates appear to be satisfactorily described by considering only the lowest-lying (S-wave) hadronic final states and assuming the kinematic factor describing phase space suppression is the same as that for free quarks. For example, the rate for $D_s$ semileptonic decay is known to be $(17.0 \\pm 5.3)%$ lower than those for $D^0$ or $D^+$, and the model accounts for this difference. When applied to hadrons containing $b$ quarks, this method implies that the $B_s$ semileptonic decay rate is about 1% higher than that of the nonstrange $B$ mesons. This small difference thus suggests surprisingly good local quark-hadron duality for $B$ semileptonic decays, complementing the expectation based on inclusive quark-hadron duality that these differences in rates should not exceed a few tenths of a percent. For $\\Lambda_b$ semileptonic decay, however, the inclusive rate is predicted to be about 13% greater than that of the nonstrange $B$ mesons. This value, representing a considerable departure from a calculation using a heavy quark expansion, is close to the corresponding experimental ratio $\\Gamma(\\Lambda_b)/ \\bar \\Gamma(B) = 1.13 \\pm 0.03$ of total decay rates.
Hydraulic system for a ratio change transmission
Kalns, Ilmars (Northville, MI)
Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.
Flexible Conversion Ratio Fast Reactor Systems Evaluation
Neil Todreas; Pavel Hejzlar
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.
Real-Time SCADA Cyber Protection Using Compression Techniques
Lyle G. Roybal; Gordon H Rueff
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.
Compressive auto-indexing in femtosecond nanocrystallography
Maia, F R N C; Marchesini, S; 10.1016/j.ultramic.2010.10.016
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.
Word aligned bitmap compression method, data structure, and apparatus
Wu, Kesheng; Shoshani, Arie; Otoo, Ekow
The Word-Aligned Hybrid (WAH) bitmap compression method and data structure is a relatively efficient method for searching and performing logical, counting, and pattern location operations upon large datasets. The technique is comprised of a data structure and methods that are optimized for computational efficiency by using the WAH compression method, which typically takes advantage of the target computing system's native word length. WAH is particularly apropos to infrequently varying databases, including those found in the on-line analytical processing (OLAP) industry, due to the increased computational efficiency of the WAH compressed bitmap index. Some commercial database products already include some version of a bitmap index, which could possibly be replaced by the WAH bitmap compression techniques for potentially increased operation speed, as well as increased efficiencies in constructing compressed bitmaps. Combined together, this technique may be particularly useful for real-time business intelligence. Additional WAH applications may include scientific modeling, such as climate and combustion simulations, to minimize search time for analysis and subsequent data visualization.
Seneca Compressed Air Energy Storage (CAES) Project
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
Abundance ratios in hierarchical galaxy formation
D. Thomas
The chemical enrichment and stellar abundance ratios of galaxies which form in a hierarchical clustering scheme are calculated. For this purpose I adopt the star formation histories (SFH) as they are delivered by semi-analytic models in Kauffmann (1996}. It turns out that the average SFH of cluster ellipticals does not yield globally alpha-enhanced stellar populations. The star burst that occurs when the elliptical forms in the major merger plays therefore a crucial role in producing alpha-enhancement. Only under the assumption that the IMF is significantly flattened with respect to the Salpeter value during the burst, a Mg/Fe overabundant population can be obtained. In particular for the interpretation of radial gradients in metallicity and alpha-enhancement, the mixing of global and burst populations are of great importance. The model predicts bright field galaxies to be less alpha-enhanced than their counterparts in clusters.
Compressive strength of concrete and mortar containing fly ash
Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)
The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.
Compressive strength of concrete and mortar containing fly ash
Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.
The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.
Compressive strength of concrete and mortar containing fly ash
Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)
The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.
Compressive strength of concrete and mortar containing fly ash
Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.
The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.
Indentation size effect and the plastic compressibility of glass
Smedskjaer, Morten M., E-mail: firstname.lastname@example.com [Section of Chemistry, Aalborg University, 9000 Aalborg (Denmark)
Oxide glasses exhibit significant densification under an applied isostatic pressure at the glass transition temperature. The glass compressibility is correlated with the chemical composition and atomic packing density, e.g., borate glasses with planar triangular BO{sub 3} units are more disposed for densification than silicate glasses with tetrahedral units. We here show that there is a direct relation between the plastic compressibility following hot isostatic compression and the extent of the indentation size effect (ISE), which is the decrease of hardness with indentation load exhibited by most materials. This could suggest that the ISE is correlated with indentation-induced shear bands, which should form in greater density when the glass network is more adaptable to volume changes through structural and topological rearrangements under an applied pressure.
A compression scheme for radio data in high performance computing
Masui, Kiyoshi; Connor, Liam; Deng, Meiling; Fandino, Mateus; H�fer, Carolin; Halpern, Mark; Hanna, David; Hincks, Adam D; Hinshaw, Gary; Parra, Juan Mena; Newburgh, Laura B; Shaw, J Richard; Vanderlinde, Keith
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.
Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II), a novel pulse-compressing ion accelerator
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
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.
Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II),a novel pulse-compressing ion accelerator
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.
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.
Spatial compression algorithm for the analysis of very large multivariate images
Keenan, Michael R. (Albuquerque, NM)
A method for spatially compressing data sets enables the efficient analysis of very large multivariate images. The spatial compression algorithms use a wavelet transformation to map an image into a compressed image containing a smaller number of pixels that retain the original image's information content. Image analysis can then be performed on a compressed data matrix consisting of a reduced number of significant wavelet coefficients. Furthermore, a block algorithm can be used for performing common operations more efficiently. The spatial compression algorithms can be combined with spectral compression algorithms to provide further computational efficiencies.
Ignition properties of n-butane and iso-butane in a rapid compression machine
Gersen, S.; Darmeveil, J.H. [Gasunie Engineering and Technology, P.O. Box 19, 9700 MA Groningen (Netherlands); Mokhov, A.V. [Laboratory for Fuel and Combustion Science, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Levinsky, H.B. [Gasunie Engineering and Technology, P.O. Box 19, 9700 MA Groningen (Netherlands); Laboratory for Fuel and Combustion Science, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)
Autoignition delay times of n-butane and iso-butane have been measured in a Rapid Compression Machine in the temperature range 660-1010 K, at pressures varying from 14 to 36 bar and at equivalence ratios {phi} = 1.0 and {phi} = 0.5. Both butane isomers exhibit a negative-temperature-coefficient (NTC) region and, at low temperatures, two-stage ignition. At temperatures below {proportional_to}900 K, the delay times for iso-butane are longer than those for the normal isomer, while above this temperature both butanes give essentially the same results. At temperatures above {proportional_to}720 K the delay times of the lean mixtures are twice those for stoichiometric compositions; at T < 720 K, the equivalence ratio is seen to have little influence on the ignition behavior. Increasing the pressure from 15 bar to 30 bar decreases the amplitude of the NTC region, and reduces the ignition delay time for both isomers by roughly a factor of 3. In the region in which two-stage ignition is observed, 680-825 K, the duration of the first ignition stage decreases sharply in the range 680-770 K, but is essentially flat above 770 K. Good quantitative agreement is found between the measurements and calculations for n-butane using a comprehensive model for butane ignition, including both delay times in the two-stage region, with substantial differences being observed for iso-butane, particularly in the NTC region. (author)
A rapid compression machine study of the oxidation of propane in the negative temperature coefficient regime
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)
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)
p/pi Ratio in Di-Hadron Correlations
Misha Veldhoen; for the ALICE Collaboration
Particle ratios are important observables used to constrain models of particle production in heavy-ion collisions. In this work we report on a measurement of the p/pi ratio in the transverse momentum range 2.0 p_{T,assoc} p_{T,trig} p/pi ratio in the bulk region is compatible with the p/pi ratio of an inclusive measurement, and is much larger than the p/pi ratio in the jet peak. The p/pi ratio in the jet peak is compatible with a PYTHIA reference, in which fragmentation in the vacuum is the dominant mechanism of particle production.
Compressed supersymmetry after 1 fb?� at the Large Hadron Collider
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
LeCompte, Thomas J.; Martin, Stephen P.
We study the reach of the Large Hadron Collider with 1 fb?� of data at ?s=7 TeV for several classes of supersymmetric models with compressed mass spectra, using jets and missing transverse energy cuts like those employed by ATLAS for summer 2011 data. In the limit of extreme compression, the best limits come from signal regions that do not require more than 2 or 3 jets and that remove backgrounds by requiring more missing energy rather than a higher effective mass.
Target Plasma Formation for Magnetic Compression/Magnetized Target Fusion
Lindemuth, I.R.; Reinovsky, R.E.; Chrien, R.E.; Christian, J.M.; Ekdahl, C.A.; Goforth, J.H.; Haight, R.C.; Idzorek, G.; King, N.S.; Kirkpatrick, R.C.; Larson, R.E.; Morgan, G.L.; Olinger, B.W.; Oona, H.; Sheehey, P.T.; Shlachter, J.S.; Smith, R.C.; Veeser, L.R.; Warthen, B.J.; Younger, S.M. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Chernyshev, V.K.; Mokhov, V.N.; Demin, A.N.; Dolin, Y.N.; Garanin, S.F.; Ivanov, V.A.; Korchagin, V.P.; Mikhailov, O.D.; Morozov, I.V.; Pak, S.V.; Pavlovskii, E.S.; Seleznev, N.Y.; Skobelev, A.N.; Volkov, G.I.; Yakubov, V.A. [All-Russian Scientific Research Institute of Experimental Physics, Arzamas-16 (Russian Federation)] [All-Russian Scientific Research Institute of Experimental Physics, Arzamas-16 (Russian Federation)
Experimental observations of plasma behavior in a novel plasma formation chamber are reported. Experimental results are in reasonable agreement with two-dimensional magnetohydrodynamic computations suggesting that the plasma could subsequently be adiabatically compressed by a magnetically driven pusher to yield 1 GJ of fusion energy. An explosively driven helical flux compression generator mated with a unique closing switch/opening switch combination delivered a 2.7 MA, 347 {mu}s magnetization current and an additional 5 MA, 2.5 {mu}s electrical pulse to the chamber. A hot plasma was produced and 10{sup 13} D-T fusion reactions were observed.
Tensile and compressive behavior of a swirl mat composite
Ruggles, M.B.
The Durability of Lightweight Composite Structures Project was established at Oak Ridge National Laboratory (ORNL) by the US Department of Energy to provide the experimentally-based, durability-driven design guidelines necessary to assure long-term structural integrity of automotive composite components. The initial focus of the ORNL Durability Project was on one representative reference material--an isocyanurate (polyurethane) reinforced with continuous strand, swirl-mat E-glass. The present report describes tensile and compressive testing and results for the reference composite. Behavior trends and proportional limit are established for both tension and compression. Damage development due to tensile loading and strain rate effects are discussed.
Benchmarking Compressed Sensing, Super-Resolution, and Filter Diagonalization
Markovich, Thomas; Sanders, Jacob N; Aspuru-Guzik, Alan
Signal processing techniques have been developed that use different strategies to bypass the Nyquist sampling theorem in order to recover more information than a traditional discrete Fourier transform. Here we examine three such methods: filter diagonalization, compressed sensing, and super-resolution. We apply them to a broad range of signal forms commonly found in science and engineering in order to discover when and how each method can be used most profitably. We find that filter diagonalization provides the best results for Lorentzian signals, while compressed sensing and super-resolution perform better for arbitrary signals.
Compressed Air System Analysis and Retrofit for Energy Savings�
Harding, C.; Nutter, D.
. 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...
Compressive turbulent cascade and heating in the solar wind
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)
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.
A boost for the EW SUSY hunt: monojet-like search for compressed sleptons at LHC14 with 100 fb^-1
Alan Barr; James Scoville
Current Large Hadron Collider (LHC) analyses are blind to compressed supersymmetry (SUSY) models with sleptons near the lightest super partner (LSP) in mass: $m_{\\tilde{l}} - m_{\\tilde{\\chi}_1^0} \\equiv \\Delta m \\lesssim 60$ GeV. We present a search sensitive to the very compressed range $3~\\text{GeV} 100$ GeV). The sleptons recoil against the jet boosting them and their decay products, making the leptons detectable and providing substantial missing transverse momentum. We use the kinematic variable $m_{\\rm T 2}$ along with a different-flavor control region to reduce the large standard model backgrounds and control systematic uncertainty. We find the analysis should allow LHC14 with $100~\\text{fb}^{-1}$ to search for degenerate left-handed selectrons and smuons in the compressed region up to $m_{\\tilde{l}_L} \\lesssim 150$ GeV. In addition, it should be sensitive to $m_{\\tilde{l}_L} \\lesssim 110$ GeV for the very challenging case of auto-concealed SUSY, in which left-handed sleptons decay to the Kaluza-Klein tower of a modulino LSP which lives in $d=6$ extra dimensions. In both the compressed spectrum and auto-concealed SUSY scenarios this analysis will need more data to improve on LEP2 limits for right-handed sleptons due to their smaller cross sections.
Low Temperature Combustion and Diesel Emission Reduction Research
Broader source: Energy.gov (indexed) [DOE]
Compression ratio control Enablers: Advanced controls Variable Valve Timing Two-stage turbo-charging CoolingEGR Two stage combustion Fuel CN reduction Vaporization too slow...
Sex ratios in the rodent malaria parasite, Plasmodium chabaudi�
Reece, S E; Duncan, Alison B; West, Stuart A; Read, Andrew F
The sex ratios of malaria and related Apicomplexan parasites play a major role in transmission success. Here, we address 2 fundamental issues in the sex ratios of the rodent malaria parasite, Plasmodium chabaudi. First we ...
Ultra-short nacelles for low fan pressure ratio propulsors
Peters, Andreas, Ph. D. Massachusetts Institute of Technology
This thesis addresses the uncharted inlet and nacelle design space for low pressure ratio fans for advanced aeroengines. A key feature in low fan pressure ratio (FPR) propulsors with short inlets and nacelles is the increased ...
374 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 55, NO. 1, JANUARY 2009 Representation and Compression of Multidimensional
. Index Terms--Compression, discontinuities, metric entropy, multidimensional signals, multiscale and Compression of Multidimensional Piecewise Functions Using Surflets Venkat Chandrasekaran, Student Member, IEEE--We study the representation, approximation, and compression of functions in M dimensions that consist
Kouzuma, S. [School of International Liberal Studies, Chukyo University, Toyota 470-0393 (Japan); Yamaoka, H., E-mail: email@example.com, E-mail: email@example.com [Department of Physics, Kyushu University, Fukuoka 812-8581 (Japan)
We present the properties of the ensemble variability V for nearly 5000 near-infrared active galactic nuclei (AGNs) selected from the catalog of Quasars and Active Galactic Nuclei (13th Edition) and the SDSS-DR7 quasar catalog. From three near-infrared point source catalogs, namely, Two Micron All Sky Survey (2MASS), Deep Near Infrared Survey (DENIS), and UKIDSS/LAS catalogs, we extract 2MASS-DENIS and 2MASS-UKIDSS counterparts for cataloged AGNs by cross-identification between catalogs. We further select variable AGNs based on an optimal criterion for selecting the variable sources. The sample objects are divided into subsets according to whether near-infrared light originates by optical emission or by near-infrared emission in the rest frame; and we examine the correlations of the ensemble variability with the rest-frame wavelength, redshift, luminosity, and rest-frame time lag. In addition, we also examine the correlations of variability amplitude with optical variability, radio intensity, and radio-to-optical flux ratio. The rest-frame optical variability of our samples shows negative correlations with luminosity and positive correlations with rest-frame time lag (i.e., the structure function, SF), and this result is consistent with previous analyses. However, no well-known negative correlation exists between the rest-frame wavelength and optical variability. This inconsistency might be due to a biased sampling of high-redshift AGNs. Near-infrared variability in the rest frame is anticorrelated with the rest-frame wavelength, which is consistent with previous suggestions. However, correlations of near-infrared variability with luminosity and rest-frame time lag are the opposite of these correlations of the optical variability; that is, the near-infrared variability is positively correlated with luminosity but negatively correlated with the rest-frame time lag. Because these trends are qualitatively consistent with the properties of radio-loud quasars reported by some previous studies, most of our sample objects are probably radio-loud quasars. Finally, we also discuss the negative correlations seen in the near-infrared SFs.
Variable rate CELP speech coding using widely variable parameter updates
Moodie, Myron L.
bit rates for a given quality level. This work develops new techniques, referred to as widely variable CELP parameter updates, which dynamically adapt the transmit frequency of the CELP spectral parameters to the characteristics of the input speech...
Monitoring System Used to Optimize Compressed Air System Efficiency, Cut Costs
Holmes, W. A.
feeders, and major equipment and systems including compressed air. For the compressed air system, monitored data included compressor amps, electrical demand and consumption, pressure and airflow. The resulting UtiliTRACK� reports and graphs showed a...
A new and efficient error resilient entropy code for image and video compression
Min, Jungki
Image and video compression standards such as JPEG, MPEG, H.263 are severely sensitive to errors. Among typical error propagation mechanisms in video compression schemes, loss of block synchronization causes the worst result. Even one bit error...
Effects of electrode compression on the performance of a solid polymer electrolyte fuel cell
Del Campo, Christopher Scott
The effects of electrode compression on the performance of a polymer electrolyte fuel cell (PEFC) were investigated. Preliminary testing showed that considerable compression of the carbon cloth electrodes was provided by the PEFC structure. Further...
Extension of the high load limit in the Homogeneous Charge Compression Ignition engine
Scaringe, Robert J. (Robert Joseph)
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 ...
Optical, electronic, and dynamical phenomena in the shock compression of condensed matter
Reed, Evan J. (Evan John), 1976-
Despite the study of shock wave compression of condensed matter for over 100 years, scant progress has been made in understanding the microscopic details. This thesis explores microscopic phenomena in shock compression of ...
3D microstructure modeling of compressed fiber-based Gerd Gaiselmanna,
Schmidt, Volker
consideration of compression conditions as found in fuel cells. Given the input of a 3D microstructure of some compression states, an optimal vector field is estimated by simulated annealing. The model is applied to 3D im
FUJIFILM Hunt Chemicals U.S.A. Achieves Compressed Air System...
Broader source: Energy.gov (indexed) [DOE]
FUJIFILM Hunt Chemicals U.S.A. Achieves Compressed Air System Energy-Reduction Goals with a Three-Phased Strategy FUJIFILM Hunt Chemicals U.S.A. Achieves Compressed Air System...
Evaluating the Gap Between Compressive Sensing and Distributed Source Coding in WSN
Rossi, Michele
providing the best compression performance and the latter being the most energy efficient in terms of local is based on the premise that compressed data implies the transmission of smaller packets. This, in turn
RATE OF STRAIN TENSOR STATISTICS IN COMPRESSIBLE HOMOGENEOUS G. Erlebacher 1 , S. Sarkar 1
Erlebacher, Gordon
RATE OF STRAIN TENSOR STATISTICS IN COMPRESSIBLE HOMOGENEOUS TURBULENCE G. Erlebacher 1 , S. Sarkar was determined in Sarkar, Erlebacher and Hus saini (ref. 2) to be due to enhanced compressible dis sipation
Abstract--Heart rate variability (HRV) is frequently used to measure autonomic nervous system (ANS) activity. However,
1 of 4 Abstract--Heart rate variability (HRV) is frequently used to measure autonomic nervous frequency (HF) ratio with little change in mean heart rate. Results suggest that nicotine affects both components may yield erroneous results. Keywords--Autonomic regulation, heart rate variability, Lomb
Quantum information with modular variables
A. Ketterer; S. P. Walborn; A. Keller; T. Coudreau; P. Milman
We introduce a novel strategy, based on the use of modular variables, to encode and deterministically process quantum information using states described by continuous variables. Our formalism leads to a general recipe to adapt existing quantum information protocols, originally formulated for finite dimensional quantum systems, to infinite dimensional systems described by continuous variables. This is achieved by using non unitary and non-gaussian operators, obtained from the superposition of gaussian gates, together with adaptative manipulations in qubit systems defined in infinite dimensional Hilbert spaces. We describe in details the realization of single and two qubit gates and briefly discuss their implementation in a quantum optical set-up.
LETTERS GLOBAL STABILITY STUDY OF THE ULTRALOW ASPECT RATIO TOKAMAK, ULART M. YAMADA, N. POMPHREY of the TS-3device at Tokyo Univesity, ultralow aspect ratio tokamak (ULART) configurations have been of the tiltishift modes agree well with the TS-3 data. 1. INTRODUCTION In recent years, low aspect ratio tokamak
XML Structure Compression Mark Levene and Peter Wood
Levene, Mark
(www.gzip.org/) or bzip2 (sourceware.cygnus.com/bzip2/index.html). The problems with this approach existing text compressors. Another XML compression system, XMLPPM, refines this idea further by using different text compressors with different XML components, i.e. one model for element and attribute
Energy Efficient Signal Acquisition in Wireless Sensor Networks : A Compressive
Cambridge, University of
and transmission. To save the energy in WSNs and thus prolong the network lifetime, we present a novel approach1 Energy Efficient Signal Acquisition in Wireless Sensor Networks : A Compressive Sensing Framework networks (WSNs) determines the rate of its energy consumption since most of the energy is used in sampling
Compressed Index for Dictionary Matching with One Error
Hon, Wing-Kai; Lam, Tak-Wah; Shah, Rahul; Siu-Lung, Tam; Vitter, Jeffrey Scott
. (1999), which requires O(n^{1+epsilon}) words of space and reports all occurrences in O(|T|loglog n + occ) time. Recently, there have been successes in compressing the dictionary matching index while keeping the query time optimal (Belazzougui, 2010, Hon...
POSTER PRESENTATION Open Access Compressed sensing with stochastic spikes
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
Inexpensive delivery of compressed hydrogen with advanced vessel technology
of flexible refueling (compressed/cryogenic H2/(L)H2) #12;The PVT properties of H2 drive storage and delivery) Explore station demand from 70 kg H2/day to 1000 kg H2/day � Real hydrogen thermodynamic and PVT diagram and vessel characteristics to minimize delivery cost � Hydrogen and material properties Increased
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
Compression of Computer Graphics Images with Image-Based Rendering
Shahabi, Cyrus
Compression of Computer Graphics Images with Image-Based Rendering Ilmi Yoon and Ulrich Neumann information from previously rendered images. Images predicted from prior images are combined with a residual-based rendering tech- nique provides accurate motion prediction and accelerates rendering at the same time
Densities and Compressibilities of Chiral Molecules in the Liquid State
Baltisberger, Jay H.
polarized light into circularly polarized light. #12;Objective · Measure the speed of sound in Limonene 1360 15 20 25 30 35 40 45 50 55 Speed of Sound (m/s) Temperature ( °C) Speed of Sound in LimoneneDensities and Compressibilities of Chiral Molecules in the Liquid State Imelda Hot and Dr. Amer S
Pulse compression in plasma: generation of femtosecond pulses without CPA
�frequency laser beam into the energy of a short lower�frequency laser pulse. The standard approach to generating high�intensity ultra�short 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
Pellet Production Wood Pellets are made by compressing
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
ESTIMATING ENERGY SAVINGS IN COMPRESSED AIR SYSTEMS Chris Schmidt
Kissock, Kelly
ESTIMATING ENERGY SAVINGS IN COMPRESSED AIR SYSTEMS Chris Schmidt Project Engineer Energy Industrial Assessment Center Department of Mechanical Engineering University of Dayton Dayton, Ohio ABSTRACT energy savings must be calculated in order to justify the cost of implementing the savings opportunity
Improvements to the Block Sorting Text Compression Algorithm
Fenwick, Peter
that it is a contextbased compressor of unbounded order, but those contexts are completely restructured by the sort that the requirements on the final compression stage are quite different from those in compressors of more conventional, eventually yielding a compressor which is among the best so far presented and is actually based
Experiments with a Block Sorting Text Compression Algorithm
Fenwick, Peter
compressors. The original paper did little more than present the algorithm, with strong advice for efficient on aspects of its operation. Consideration of the possible efficiency of text compression leads to the revival of ideas by Shannon as the basis of a text compressor and then to the classification of the Block
Compressive Strength of Gamma-Irradiated Polymer Concrete
North Texas, University of
Compressive Strength of Gamma-Irradiated Polymer Concrete Gonzalo Marti´nez-Barrera,1,2 Uriel concrete (PC) was developed by using differ- ent concentrations of silica sand as aggregate of Plastics Engineers INTRODUCTION Polymer concrete (PC) is a particulate composite where thermoset resins
Hunana, P.; Goldstein, M. L. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Passot, T.; Sulem, P. L.; Laveder, D. [Laboratoire J. L. Lagrange, Universite de Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, BP 4229, F-06304 Nice Cedex 4 (France)] [Laboratoire J. L. Lagrange, Universite de Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, BP 4229, F-06304 Nice Cedex 4 (France); Zank, G. P. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35805 (United States)] [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35805 (United States)
It is well known that a complete description of the solar wind requires a kinetic description and that, particularly at sub-proton scales, kinetic effects cannot be ignored. It is nevertheless usually assumed that at scales significantly larger than the proton gyroscale r{sub L} , magnetohydrodynamics or its extensions, such as Hall-MHD and two-fluid models with isotropic pressures, provide a satisfactory description of the solar wind. Here we calculate the polarization and magnetic compressibility of oblique kinetic Alfven waves and show that, compared with linear kinetic theory, the isotropic two-fluid description is very compressible, with the largest discrepancy occurring at scales larger than the proton gyroscale. In contrast, introducing anisotropic pressure fluctuations with the usual double-adiabatic (or CGL) equations of state yields compressibility values which are unrealistically low. We also show that both of these classes of fluid models incorrectly describe the electric field polarization. To incorporate linear kinetic effects, we use two versions of the Landau fluid model that include linear Landau damping and finite Larmor radius (FLR) corrections. We show that Landau damping is crucial for correct modeling of magnetic compressibility, and that the anisotropy of pressure fluctuations should not be introduced without taking into account the Landau damping through appropriate heat flux equations. We also show that FLR corrections to all the retained fluid moments appear to be necessary to yield the correct polarization. We conclude that kinetic effects cannot be ignored even for kr{sub L} << 1.
On optimally partitioning a text to improve its compression
Ferragina, Paolo; Venturini, Rossano
In this paper we investigate the problem of partitioning an input string T in such a way that compressing individually its parts via a base-compressor C gets a compressed output that is shorter than applying C over the entire T at once. This problem was introduced in the context of table compression, and then further elaborated and extended to strings and trees. Unfortunately, the literature offers poor solutions: namely, we know either a cubic-time algorithm for computing the optimal partition based on dynamic programming, or few heuristics that do not guarantee any bounds on the efficacy of their computed partition, or algorithms that are efficient but work in some specific scenarios (such as the Burrows-Wheeler Transform) and achieve compression performance that might be worse than the optimal-partitioning by a $\\Omega(\\sqrt{\\log n})$ factor. Therefore, computing efficiently the optimal solution is still open. In this paper we provide the first algorithm which is guaranteed to compute in $O(n \\log_{1+\\eps}...
Ris-R-1393(EN) Compression Strength of a Fibre
Risø-R-1393(EN) Compression Strength of a Fibre Composite Main Spar in a Wind Turbine Blade Find out in the project "Fun- damentals for improved design of large wind turbine blade of fibre composites of a wind turbine blade is found and compared with a full-scale test, made in the same project. Especially
Digitally-Assisted Mixed-Signal Wideband Compressive Sensing
Yu, Zhuizhuan
knowledge, this prototype is the first reported integrated chip for wideband mixed-signal compressive sensing. The proposed prototype achieves 7 bits ENOB and 3 GS/s equivalent sampling rate in simulation assuming a 0.5 ps state-of-art jitter variance, whose...
Dynamic Phase Boundaries for Compressible Fluids , Z. L. Xu
New York at Stoney Brook, State University of
discontinuity. The emphasis here is on the coupling of the phase transition process to acoustic waves, whichDynamic Phase Boundaries for Compressible Fluids T. Lu § , Z. L. Xu § , R. Samulyak§ , J. Glimm algorithm is verified by application to various physical regimes. 1 Introduction The coupling
Random Access Compressed Sensing over Fading and Noisy Communication Channels
Stojanovic, Milica
of the climate change. Such applications require the least control and intervention as well as minimum energy1 Random Access Compressed Sensing over Fading and Noisy Communication Channels Fatemeh Fazel on integrating random sensing with the communication architecture, and achieves overall efficiency in terms
Waldron, W.L.; Kwan, J.W.
The Neutralized Drift Compression Experiment (NDCX-II) is an 11 M$ induction accelerator project currently in construction at Lawrence Berkeley National Laboratory for warm dense matter (WDM) experiments investigating the interaction of ion beams with matter at elevated temperature and pressure. The machine consists of a lithium injector, induction accelerator cells, diagnostic cells, a neutralized drift compression line, a final focus solenoid, and a target chamber. The induction cells and some of the pulsed power systems have been reused from the decommissioned Advanced Test Accelerator at Lawrence Livermore National Laboratory after refurbishment and modification. The machine relies on a sequence of acceleration waveforms to longitudinally compress the initial ion pulse from 600 ns to less than 1 ns in {approx} 12 m. Radial confinement of the beam is achieved with 2.5 T pulsed solenoids. In the initial hardware configuration, 50 nC of Li{sup +} will be accelerated to 1.25 MeV and allowed to drift-compress to a peak current of {approx}40 A. The project started in the summer of 2009. Construction of the accelerator will be completed in the fall of 2011 and will provide a worldwide unique opportunity for ion-driven warm dense matter experiments as well as research related to novel beam manipulations for heavy ion fusion drivers.
Kurien, Susan
� . Scalar quantities (density , pressure p, specific internal energy and temperature T) are approximated Lagrangian system is numerically treated by compatible method [8, 9] conserving total energy. Several types Lagrangian-Eulerian (ALE [1]) code for simulation of problems in compressible fluid dynamics and plasma
Compression of redundancy free trellis stages in Turbo-Decoder
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
Vortex stabilized electron beam compressed fusion grade plasma
Hershcovitch, Ady [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.
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.
NUMERICAL INVESTIGATION OF CAVITATION IN MULTI-DIMENSIONAL COMPRESSIBLE FLOWS KRISTEN J. DEVAULT, cavitation, pseudospectral AMS subject classifications. 35Q30, 65M70, 76N99 1. Introduction. A long to first make a careful numerical study of the simplest possible scenario where one could expect cavitation
Ch. 15 Wavelet-Based Compression The Wavelet Transform
Fowler, Mark
sent to describe allocations WT-BASED COMPRESSION EXAMPLE Time Frequency #12;42 From http://www.amara.com/IEEEwave/IW_fbi.html See also http://www.c3.lanl.gov/~brislawn/FBI/FBI.html Original Fingerprint Image Decoded Fingerprint
COMPRESSIVE DEFORMATION AND YIELDING MECHANISMS IN CELLULAR Al ALLOYS DETERMINED
Wadley, Haydn
compressive stress/strain characteristics that enhance the thermomechanical performance of buckling or bending is used as an interior for a double-walled tube, its ability to suppress local buckling leads to slightly enhanced structural eciency [Fig. 1(a)] [1]. Moreover, and more importantly, by suppressing lateral defor
Beyond Leaks: Demand-side Strategies for Improving Compressed Air Efficiency
Howe, B.; Scales, B.
Beyond Leaks: Demand-side Strategies for Bill Howe, PE Director, Corporate Energy Services E Source, Inc. Boulder, Colorado SUMMARY Staggering amounts of compressed air are wasted or misapplied in otherwise well run manufacturing...-maintained plants lose about 10 percent of compressed air to leaks, while many more lose over 50 percent. In addition to leaks, wasteful application of compressed air can eat up another 5 to 40 percent of compressed air volume-even in otherwise well...
Evolution of some Los Alamos flux compression programs
Fowler, C.M.; Goforth, J.H.
When we were approached to give a general discussion of some aspects of the Los Alamos flux compression program, we decided to present historical backgrounds of a few topics that have some relevance to programs that we very much In the forefront of activities going on today. Of some thirty abstracts collected at Los Alamos for this conference, ten of them dealt with electromagnetic acceleration of materials, notably the compression of heavy liners, and five dealt with plasma compression. Both of these topics have been under investigation, off and on, from the time a formal flux compression program was organized at Los Alamos. We decided that a short overview of work done In these areas would be of some interest. Some of the work described below has been discussed in Laboratory reports that, while referenced and available, are not readily accessible. For completeness, some previously published, accessible work Is also discussed but much more briefly. Perhaps the most striking thing about the early work In these two areas is how primitive much of it was when compared to the far more sophisticated, related activities of today. Another feature of these programs, actually for most programs, Is their cyclic nature. Their relevance and/or funding seems to come land go. Eventually, many of the older programs come back into favor. Activities Involving the dense plasma focus (DPF), about which some discussions will be given later, furnish a classic example of this kind, coming Into and then out of periods of heightened interest. We devote the next two sections of this paper to a review of our work In magnetic acceleration of solids and of plasma compression. A final section gives a survey of our work In which thin foils are imploded to produce intense quantities of son x-rays. The authors are well aware of much excellent work done elsewhere In all of these topics, but partly because of space limitations, have confined this discussion to work done at Los Alamos.
An experimental and modeling study of iso-octane ignition delay times under homogeneous charge compression ignition conditions
He, X.; Donovan, M.T.; Zigler, B.T.; Palmer, T.R.; Walton, S.M.; Wooldridge, M.S.; Atreya, A. [Department of Mechanical Engineering, University of Michigan, 2350 Hayward Street, Ann Arbor, MI 48109-2125 (United States)
Autoignition of iso-octane was examined using a rapid compression facility (RCF) with iso-octane, oxygen, nitrogen, and argon mixtures. The effects of typical homogeneous charge compression ignition (HCCI) conditions on the iso-octane ignition characteristics were studied. Experimental results for ignition delay times, t{sub ign}, were obtained from pressure time-histories. The experiments were conducted over a range of equivalence ratios (f=0.25-1.0), pressures (P=5.12-23 atm), temperatures (T=943-1027 K), and oxygen mole fractions ({chi}{sub O{sub 2}}=9-21%), and with the addition of trace amounts of combustion product gases (CO{sub 2} and H{sub 2}O). It was found that the ignition delay times were well represented by the expression t{sub ign}=1.3x10{sup -4}P{sup -1.05}f{sup -0.77}{chi}{sub O{sub 2}}{sup -1.41}exp(33,700/R{sub (c} {sub al/mol/K)}T), where P is pressure (atm), T is temperature (K), f is the equivalence ratio (based on iso-octane to O{sub 2} molar ratios), {chi}{sub O{sub 2}} is the oxygen mole percent (%), and t{sub ign} is the ignition delay time (ms). Carbon dioxide was found to have no chemical effect on t{sub ign}. Water was found to systematically decrease t{sub ign} by a small amount (less than 14% for the range of conditions studied). The maximum uncertainty in the measured t{sub ign} is +/-12% with an average uncertainty of +/-6%. The performance of several proposed chemical reaction mechanisms (including detailed, reduced, and skeletal mechanisms) was evaluated in the context of the current experimental results.
Fractal Volume Compression Wayne O. Cochran John C. Hart Patrick J. Flynn
Fractal Volume Compression Wayne O. Cochran John C. Hart Patrick J. Flynn School of email@example.com October 18, 1995 Abstract This research is the rst application of fractal compression to volumetric data. The various components of the fractal image compression method extend simply and di- rectly to the volumetric
Performance of Multi-Level and Multi-Component Compressed Bitmap Indexes
Geddes, Cameron Guy Robinson
LBNL-60891 Performance of Multi-Level and Multi-Component Compressed Bitmap Indexes Kesheng Wu cardinality attributes when certain compression methods are applied. There are many different bitmap indexes subsets of compressed bitmap indexes that use multi-component and multi-level encodings. We combine
DIRECT NUMERICAL SIMULATION OF COMPRESSIBLE TRANSITION: AN OVERVIEW M.Y. Hussaini and G. Erlebacher
Erlebacher, Gordon
DIRECT NUMERICAL SIMULATION OF COMPRESSIBLE TRANSITION: AN OVERVIEW M.Y. Hussaini and G. Erlebacher in the field of compressible transition. As a result, new computational tools have made their appearance. Recently however, research at Langley has begun to focus on the simulation of compressible transition
Planning and Installation Guide: North Carolina Compressed Natural Gas Fueling Stations
1 Planning and Installation Guide: North Carolina Compressed Natural Gas Fueling Stations Introduction Are you considering installing a compressed natural gas (CNG) fueling station for your fleet to provide your fleet with fuel. One resource for locating and identifying public compressed natural gas
CALIBRATING MS-SSIM FOR COMPRESSION DISTORTIONS USING MLDS C. Charrier1
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
A Low-power, Low-memory System for Wavelet-based Image Compression
Walker, James S.
of the components of our particular method of wavelet transform based image compression. 2 Wavelet transformsA Low-power, Low-memory System for Wavelet-based Image Compression James S. Walker Department the following advan- tages: low-power utilization, low RAM requirements, embedded bit-plane compression, scal
BAP Sparsing: A Novel Approach to MPEG-4 Body Animation Parameter Compression
Bhandarkar, Suchendra "Suchi" M.
, such as virtual humans [1] [2]. A virtual human body model is animated using a stream of body animation parameters virtual bodies and their animation to be compressed using a standard compression pipeline comprisingBAP Sparsing: A Novel Approach to MPEG-4 Body Animation Parameter Compression Siddhartha
Leus, Geert
COMPRESSIVE SAMPLING FOR NON-INTRUSIVE APPLIANCE LOAD MONITORING (NALM) USING CURRENT WAVEFORMS advanced services like dynamic electricity pricing. The non-intrusive appliance load monitoring (NALM) [1/off status of each appliance from the compressed measurement as if the original non-compressed measurement
Partial Encryption of Compressed Images and Videos \\Lambda Howard Cheng y and Xiaobo Li z
Cheng, Howard
Partial Encryption of Compressed Images and Videos \\Lambda Howard Cheng y and Xiaobo Li z, if not impossible, to carry out realtime secure image and video communication and processing. Methods have been of the compressed data. Partial encryption is applied to several image and video compression algorithms
Anyonic statistics with continuous variables
Jing Zhang; Changde Xie; Kunchi Peng; Peter van Loock
We describe a continuous-variable scheme for simulating the Kitaev lattice model and for detecting statistics of abelian anyons. The corresponding quantum optical implementation is solely based upon Gaussian resource states and Gaussian operations, hence allowing for a highly efficient creation, manipulation, and detection of anyons. This approach extends our understanding of the control and application of anyons and it leads to the possibility for experimental proof-of-principle demonstrations of anyonic statistics using continuous-variable systems.
Variable metric conjugate gradient methods
Barth, T.; Manteuffel, T.
1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.
Anthony J. Smalley; Ralph E. Harris; Gary D. Bourn; Ford A. Phillips; Danny M. Deffenbaugh
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
Multiple-Zone Variable Refrigerant Flow System Modeling and Equipment Performance Mapping
Shen, Bo [ORNL] [ORNL; Rice, C Keith [ORNL] [ORNL
We developed a variable refrigerant flow (VRF) vapor compression system model, which has five indoor units, one outdoor unit and one water heater. The VRF system can run simultaneous space conditioning (cooling or heating) and water heating. The indoor units and outdoor unit use fin-&-tube coil heat exchangers, and the water heater uses a tube-in-tube heat exchanger. The fin-&-tube coil heat exchangers are modeled using a segment-by-segment approach and the tube-in-tube water heater is modeled using a phase-by-phase approach. The compressor used is a variable-speed rotary design. We calibrated our model against a manufacturer s product literature. Based on the vapor compression system model, we investigated the methodology for generating VRF equipment performance maps, which can be used for energy simulations in TRNSYS and EnergyPlus, etc. In the study, the major independent variables for mapping are identified and the deviations between the simplified performance map and the actual equipment system simulation are quantified.
Managing Variability throughout the Software Development Lifecycle
Managing Variability throughout the Software Development Lifecycle Neil Loughran and Awais Rashid levels of the software development lifecycle, especially when new requirements arise. We believe of the software development lifecycle. Moreover, the effects of variability and, in particular, new variabilities
Image compression/decompression based on mathematical transform, reduction/expansion, and image sharpening
Fu, C.Y.; Petrich, L.I.
An image represented in a first image array of pixels is first decimated in two dimensions before being compressed by a predefined compression algorithm such as JPEG. Another possible predefined compression algorithm can involve a wavelet technique. The compressed, reduced image is then transmitted over the limited bandwidth transmission medium, and the transmitted image is decompressed using an algorithm which is an inverse of the predefined compression algorithm (such as reverse JPEG). The decompressed, reduced image is then interpolated back to its original array size. Edges (contours) in the image are then sharpened to enhance the perceptual quality of the reconstructed image. Specific sharpening techniques are described. 22 figs.
Image compression/decompression based on mathematical transform, reduction/expansion, and image sharpening
Fu, Chi-Yung (San Francisco, CA); Petrich, Loren I. (Livermore, CA)
An image represented in a first image array of pixels is first decimated in two dimensions before being compressed by a predefined compression algorithm such as JPEG. Another possible predefined compression algorithm can involve a wavelet technique. The compressed, reduced image is then transmitted over the limited bandwidth transmission medium, and the transmitted image is decompressed using an algorithm which is an inverse of the predefined compression algorithm (such as reverse JPEG). The decompressed, reduced image is then interpolated back to its original array size. Edges (contours) in the image are then sharpened to enhance the perceptual quality of the reconstructed image. Specific sharpening techniques are described.
Quasi-Periodic Variability in NGC 5408 X-1
Tod E. Strohmayer; Richard F. Mushotzky; Lisa Winter; Roberto Soria; Phil Uttley; Mark Cropper
We report the discovery with XMM-Newton of quasiperiodic variability in the 0.2 - 10 keV X-ray flux from the ultraluminous X-ray source NGC 5408 X-1. The average power spectrum of all EPIC-pn data reveals a strong 20 mHz QPO with an average amplitude (rms) of 9%, and a coherence of Q~6. In a 33 ksec time interval when the 20 mHz QPO is strongest we also find evidence for a 2nd QPO peak at 15 mHz. This is the first indication for a close pair of QPOs in a ULX source. Interestingly, the frequency ratio of this QPO pair is inconsistent with 3:2 at the 3sigma level, but is consistent with a 4:3 ratio. A powerlaw noise component with slope near 1.5 is also present below 0.1 Hz with evidence for a break to a flatter slope at about 3 mHz. The source shows substantial broadband variability, with a total amplitude (rms) of about 30% in the 0.1 - 100 mHz frequency band, and there is strong energy dependence to the variability. We discuss the implications of these findings in the context of models for ULXs, and their implications for the object's mass.
Compression of laser radiation in plasmas via electromagnetic cascading
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)
A train of few-laser-cycle relativistically intense radiation spikes with a terahertz repetition rate can be organized self-consistently in plasma from two frequency detuned co-propagating laser beams of low intensity. Large frequency bandwidth for the compression of spikes is produced via laser-induced periodic modulation of the plasma refractive index. The beat-wave-driven electron plasma wave downshifted from the plasma frequency creates a moving index grating thus inducing a periodic phase modulation of the driving laser (in spectral terms, electromagnetic cascading). The group velocity dispersion compresses the chirped laser beat notes to a few-cycle duration and relativistic intensity either concurrently in the same, or sequentially in different plasmas. Particle-in-cell simulations indicate that the effect persists in a realistic three-dimensional axisymmetric geometry.
Ultrafast electron diffraction with radio-frequency compressed electron pulses
Chatelain, Robert P.; Morrison, Vance R.; Godbout, Chris; Siwick, Bradley J. [Departments of Physics and Chemistry, Center for the Physics of Materials, McGill University, Montreal (Canada)
We report on the complete characterization of time resolution in an ultrafast electron diffraction (UED) instrument based on radio-frequency electron pulse compression. The temporal impulse response function of the instrument was determined directly in pump-probe geometry by performing electron-laser pulse cross-correlation measurements using the ponderomotive interaction. With optimal settings, a stable impulse response of 334{+-}10 fs was measured at a bunch charge of 0.1 pC (6.24 Multiplication-Sign 10{sup 5} electrons/pulse); a dramatic improvement compared to performance without pulse compression. Phase stability currently limits the impulse response of the UED diffractometer to the range of 334-500 fs, for bunch charges ranging between 0.1 and 0.6 pC.
Shock compression experiments on Lithium Deuteride single crystals.
Knudson, Marcus D.; Desjarlais, Michael P.; Lemke, Raymond W.
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.
Explosive flux compression generators for rail gun power sources
Fowler, C.M.; Peterson, D.R.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; King, J.C.
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.
Proton radiography of a shock-compressed target
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)
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.
Isentropic compression studies using the NHMFL single turn
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
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.
Observation of Enhanced Transformer Ratio in Collinear Wakefield Acceleration
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)
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.
Costs Associated With Compressed Natural Gas Vehicle Fueling Infrastructure
Smith, M.; Gonzales, J.
This document is designed to help fleets understand the cost factors associated with fueling infrastructure for compressed natural gas (CNG) vehicles. It provides estimated cost ranges for various sizes and types of CNG fueling stations and an overview of factors that contribute to the total cost of an installed station. The information presented is based on input from professionals in the natural gas industry who design, sell equipment for, and/or own and operate CNG stations.
Shock compression of liquid helium to 56 GPa (560 kbar)
Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Trainor, R.J.; Governo, G.K.; Ross, M.; Young, D.A.
The first shock-compression experiments on liquid helium are reported. With a two-stage light-gas gun, liquid He at 4.3 K and 1 atm was shocked to 16 GPa and 12 000 K and double shocked to 56 GPa and 21 000 K. Liquid perturbation theory has been used to determine an effective interatomic potential from which the equation of state of He can be obtained over a wide range of densities and temperatures.
Evidence for Two Distinct Morphological Classes of Gamma-Ray Bursts from their Short Timescale Variability
D. Q. Lamb; C. Graziani; I. A. Smith
We have analyzed the 241 bursts for which peak counts $\\C$ exist in the publicly available Burst and Transient Source Experiment (BATSE) catalog. Introducing peak counts in 1024 ms as a measure of burst brightness $\\B$ and the ratio of peak counts in 64 and 1024 ms as a measure of short timescale variability $\\V$, we find a statistically significant correlation between the brightness and the short timescale variability of \\g-ray bursts. The bursts which are smoother on short timescales are both faint and bright, while the bursts which are variable on short timescales are faint only, suggesting the existence of two distinct morphological classes of bursts.
Experimental study and chemical analysis of n-heptane homogeneous charge compression ignition combustion with port injection of reaction inhibitors
Lue, Xingcai; Ji, Libin; Zu, Linlin; Hou, Yuchun; Huang, Cheng; Huang, Zhen [School of Mechanical and Power Engineering, Shanghai Jiaotong University, Shanghai (China)
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)
Compression of Laser Radiation in Plasmas Using Electromagnetic Cascading
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)
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.
Shockless compression and release behavior of beryllium to 110?GPa
Brown, J. L.; Knudson, M. D.; Alexander, C. S.; Asay, J. R. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)
A magnetohydrodynamic loading technique was used to shocklessly compress beryllium to peak longitudinal stresses of 19�110?GPa and, subsequently, unload in order to determine both the compressive response and also the shear stress supported upon release. Loading strain rates were on the order of 10{sup 6?}s{sup ?1}, while the unloading rates were nearly constant at 3?�?10{sup 5?}s{sup ?1}. Velocimetry was used to monitor the ramp and release behavior of a beryllium/lithium fluoride window interface. After applying window corrections to infer in situ beryllium velocities, a Lagrangian analysis was employed to determine the material response. The Lagrangian wavespeed-particle velocity response is integrated to generate the stress-strain path, average change in shear stress over the elastic unloading, and estimates of the shear modulus at peak compression. These data are used to infer the pressure dependence of the flow strength at the unloading rate. Comparisons to several strength models reveal good agreement to 45?GPa, but the data indicate 20%�30% higher strength near 100?GPa.
Centrifugal compression of soft particle packings - theory and experiment
K. N. Nordstrom; E. Verneuil; W. G. Ellenbroek; T. C. Lubensky; J. P. Gollub; D. J. Durian
An exact method is developed for computing the height of an elastic medium subjected to centrifugal compression, for arbitrary constitutive relation between stress and strain. Example solutions are obtained for power-law media and for cases where the stress diverges at a critical strain -- for example as required by packings composed of deformable but incompressible particles. Experimental data are presented for the centrifugal compression of thermo-responsive N-isopropylacrylamide (NIPA) microgel beads in water. For small radial acceleration, the results are consistent with Hertzian elasticity, and are analyzed in terms of the Young elastic modulus of the bead material. For large radial acceleration, the sample compression asymptotes to a value corresponding to a space-filling particle volume fraction of unity. Therefore we conclude that the gel beads are incompressible, and deform without deswelling. In addition, we find that the Young elastic modulus of the particulate gel material scales with cross-link density raised to the power 3.3+-0.8, somewhat larger than the Flory expectation.
Active high-power RF switch and pulse compression system
Tantawi, Sami G. (San Mateo, CA); Ruth, Ronald D. (Woodside, CA); Zolotorev, Max (Mountain View, CA)
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.
Dual equilibrium in a finite aspect ratio tokamak
Gourdain, P A
achievable in conventional tokamaks. Previous research hasin a ?nite aspect ratio tokamak P. -A. Gourdain a , b ,? ,fusion reactor is the tokamak concept, a closed magnetic
Neutrino Flavor Ratios Modified by Cosmic Ray Re-acceleration
Kawanaka, Norita
Re-acceleration of $\\pi$'s and $\\mu$'s modifies the flavor ratio at Earth (at astrophysical sources) of neutrinos produced by $\\pi$ decay, $\
aspect ratio spherical: Topics by E-print Network
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Stability Modes of Low-Aspect-Ratio Wings Matt Shields Engineering Websites Summary: vehicles (MAVs) ranging from flexiblemorphing wing aircraft to nano- and pico-scale...
aspect ratio toroidal: Topics by E-print Network
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Stability Modes of Low-Aspect-Ratio Wings Matt Shields Engineering Websites Summary: vehicles (MAVs) ranging from flexiblemorphing wing aircraft to nano- and pico-scale...
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contribute a major portion of atmospheric aerosol mass loading 5. The estimated global annual Liou, K. N. 2 Studying Clouds and Aerosols with Lidar Depolarization Ratio and...
aspect ratio aluminium: Topics by E-print Network
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perturbations Reynolds numbers Re) by means of the minimal amplitude of an initial global perturbation triggering Meseguer, Alvaro 9 Effect of mineral dust aerosol aspect ratio...
Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From...
Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From Yellowstone Drill Cores Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Oxygen...
Effective fracture geometry obtained with large water sand ratio
Kumar, Amrendra
-Pressure z Compressibility Factor viii t Time M Molecular Weight R Gas Constant T Temperature Pi Initial Reservoir Pressure q Flow Rate qsc Flow Rate at Standard Condition B Formation Volume Factor Bg Formation Gas Volume Factor Gp Cumulative... be solved with two boundaries and one initial condition. iprp =)0,( (Initial Condition) (2.34) h qB r prk wrr r pi ? 2=? ? = (Constant Rate Inner Boundary...
Low-pressure-ratio regenerative exhaust-heated gas turbine
Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.
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.
Sparsity-based optimization of two lifting-based wavelet transforms for semi-regular mesh compression
Boyer, Edmond
, and consequently high compression performances. In computer graphics, the compact representation is not the sole
In-situ neutron diffraction of LaCoO{sub 3} perovskite under uniaxial compression. II. Elastic properties
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); Aman, Amjad; Orlovskaya, Nina, E-mail: email@example.com [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); Kuebler, Jakob; Graule, Thomas [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for High Performance Ceramics, Ueberlandstrasse 129, 8600 Duebendorf (Switzerland); 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)
Calculations of elastic constants and development of elastic anisotropy under uniaxial compression in originally isotropic polycrystalline LaCoO{sub 3} perovskite are reported. The lattice strains in individual (hkl) planes as well as average lattice strain were determined both for planes oriented perpendicular and parallel to the loading direction using in-situ neutron diffraction. Utilizing average lattice strains as well as lattice strains along the a and c crystallographic directions, an attempt was made to determine Poisson's ratio of LaCoO{sub 3}, which was then compared with that measured using an impulse excitation technique. The elastic constants were calculated and Young's moduli of LaCoO{sub 3} single crystal in different crystallographic directions were estimated.
Radial Velocity Variability of Field Brown Dwarfs
Prato, L; Rice, E L; McLean, I S; Kirkpatrick, J D; Burgasser, A J; Kim, S S
We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R~20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC infrared spectrograph at the W. M. Keck Observatory. With a radial velocity precision of ~2 km/s, we are sensitive to brown dwarf companions in orbits with periods of a few years or less given a mass ratio of 0.5 or greater. We do not detect any spectroscopic binary brown dwarfs in the sample. Given our target properties, and the frequency and cadence of observations, we use a Monte Carlo simulation to determine the detection probability of our sample. Even with a null detection result, our 1 sigma upper limit for very low mass binary frequency is 18%. Our targets included 7 known, wide brown dwarf binary systems. No significant radial velocity variability was measured in our multi-epoch observations of these systems, even for those pairs for which our data spanned a significant ...
White dwarf masses in cataclysmic variables
Wijnen, T P G; Schreiber, M R
The white dwarf (WD) mass distribution of cataclysmic variables (CVs) has recently been found to dramatically disagree with the predictions of the standard CV formation model. The high mean WD mass among CVs is not imprinted in the currently observed sample of CV progenitors and cannot be attributed to selection effects. Two possibilities have been put forward: either the WD grows in mass during CV evolution, or in a significant fraction of cases, CV formation is preceded by a (short) phase of thermal time-scale mass transfer (TTMT) in which the WD gains a sufficient amount of mass. We investigate if either of these two scenarios can bring theoretical predictions and observations into agreement. We employed binary population synthesis models to simulate the present intrinsic CV population. We incorporated aspects specific to CV evolution such as an appropriate mass-radius relation of the donor star and a more detailed prescription for the critical mass ratio for dynamically unstable mass transfer. We also imp...
Renewable variable speed hybrid system�
Stott, Paul Anthony
generator island grids, these generators will be running at a fraction of maximum output for most of the time. A new variable speed diesel generator allows for a reduction in fuel consumption at part load compared to constant speed operation. Combining...
Variable Structure Control of a
Ge, Shuzhi Sam
. INTRODUCTION Modelling and control of flexible link manipulators have been studied intensively controller for regulation of a flexible beam. Due to its simplicity and robustness to parametricVariable Structure Control of a Distributed-Parameter Flexible Beam S. S. Ge,* T. H. Lee, G. Zhu, F