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Note: This page contains sample records for the topic "variable compression ratio" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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1

Eccentric crank variable compression ratio mechanism  

DOE Patents [OSTI]

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.

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

2008-05-13T23:59:59.000Z

2

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

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

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

3

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

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

th , 2012 Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains DEER Conference 2012 D. Tomazic, H. Kleeberg, S. Bowyer, FEV Inc. J....

4

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 Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyTheTwoVulnerabilities | Department of|VTA,anCompression Ratio

5

Combustion engine variable compression ratio apparatus and method  

DOE Patents [OSTI]

An apparatus and method for varying a compression ratio of an engine having a block and a head mounted thereto. The apparatus and method includes a cylinder having a block portion and a head portion, a piston linearly movable in the block portion of the cylinder, a cylinder plug linearly movable in the head portion of the cylinder, and a valve located in the cylinder plug and operable to provide controlled fluid communication with the block portion of the cylinder.

Lawrence; Keith E. (Peoria, IL); Strawbridge, Bryan E. (Dunlap, IL); Dutart, Charles H. (Washington, IL)

2006-06-06T23:59:59.000Z

6

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

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

Fuels Practical Full Time HCCI Operation Will Require Specific HCCI Fuel Low Octane gasoline Experimental Variables Experimental Variables Engine Variables Intake Manifold...

7

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

E-Print Network [OSTI]

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...

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

2012-01-01T23:59:59.000Z

8

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

SciTech Connect (OSTI)

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.

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

2007-01-01T23:59:59.000Z

9

Effect of Compression Ratio and Piston Geometry on RCCI load...  

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

Compression Ratio and Piston Geometry on RCCI load limit Effect of Compression Ratio and Piston Geometry on RCCI load limit Explores the effect of compression ratio and piston...

10

Variable ratio regenerative braking device  

DOE Patents [OSTI]

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.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15T23:59:59.000Z

11

Prediction-Based Compression Ratio Boundaries for Medical Images  

E-Print Network [OSTI]

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

Qi, Xiaojun

12

Variable valve timing in a homogenous charge compression ignition engine  

DOE Patents [OSTI]

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.

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

2004-08-03T23:59:59.000Z

13

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

E-Print Network [OSTI]

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 ...

Gerty, Michael D

2005-01-01T23:59:59.000Z

14

High compression ratio turbo gasoline engine operation using alcohol enhancement  

E-Print Network [OSTI]

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 ...

Lewis, Raymond (Raymond A.)

2013-01-01T23:59:59.000Z

15

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

SciTech Connect (OSTI)

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.

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

2007-01-01T23:59:59.000Z

16

SciTech Connect: Envera Variable Compression Ratio Engine  

Office of Scientific and Technical Information (OSTI)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article:Biasi, A.long baseline neutrino experiment" Find +Search ResultsName Name

17

Evaluation of Variable Compression Ratio on Energy Efficiency | Department  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat PumpRecord ofESPCof EnergyHouse11 DOE Hydrogen and Fuel|Skutterudite-Basedof

18

Variable compression ratio device for internal combustion engine  

DOE Patents [OSTI]

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.

Maloney, Ronald P.; Faletti, James J.

2004-03-23T23:59:59.000Z

19

Influence of Transport Variables on Isospin Transport Ratios  

E-Print Network [OSTI]

The symmetry energy in the nuclear equation of state affects many aspects of nuclear astrophysics, nuclear structure, and nuclear reactions. Recent constraints from heavy ion collisions, including isospin diffusion observables, have started to put constraints on the symmetry energy below nuclear saturation density, but these constraints depend on the employed transport model and input physics other than the symmetry energy. To understand these dependencies, we study the influence of the symmetry energy, isoscaler mean field compressibility and momentum dependence, in-medium nucleon-nucleon cross sections, and light cluster production on isospin diffusion within the pBUU transport code. In addition to the symmetry energy, several uncertain issues strongly affect isospin diffusion, most notably the cross sections and cluster production. In addition, there is a difference in the calculated isospin transport ratios, depending upon whether they are computed using the isospin asymmetry of either the residue or of a...

Coupland, D D S; Tsang, M B; Danielewicz, P; Zhang, Yingxun

2011-01-01T23:59:59.000Z

20

Influence of Transport Variables on Isospin Transport Ratios  

E-Print Network [OSTI]

The symmetry energy in the nuclear equation of state affects many aspects of nuclear astrophysics, nuclear structure, and nuclear reactions. Recent constraints from heavy ion collisions, including isospin diffusion observables, have started to put constraints on the symmetry energy below nuclear saturation density, but these constraints depend on the employed transport model and input physics other than the symmetry energy. To understand these dependencies, we study the influence of the symmetry energy, isoscaler mean field compressibility and momentum dependence, in-medium nucleon-nucleon cross sections, and light cluster production on isospin diffusion within the pBUU transport code. In addition to the symmetry energy, several uncertain issues strongly affect isospin diffusion, most notably the cross sections and cluster production. In addition, there is a difference in the calculated isospin transport ratios, depending upon whether they are computed using the isospin asymmetry of either the residue or of all forward moving fragments. Measurements that compare the isospin transport ratios of these two quantities would help place constraints on the input physics, such as the density dependence of the symmetry energy.

D. D. S. Coupland; W. G. Lynch; M. B. Tsang; P. Danielewicz; Yingxun Zhang

2011-07-19T23:59:59.000Z

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


21

Formation of compressed flat electron beams with high transverse-emittance ratios  

SciTech Connect (OSTI)

Flat beams—beams with asymmetric transverse emittances—have important applications in novel light-source concepts and advanced-acceleration schemes and could possibly alleviate the need for damping rings in lepton colliders. Over the last decade, a flat beam generation technique based on the conversion of an angular-momentum-dominated beam was proposed and experimentally tested. In this paper we explore the production of compressed flat beams. We especially investigate and optimize the flat beam transformation for beams with substantial fractional energy spread. We use as a simulation example the photoinjector of Fermilab’s Advanced Superconducting Test Accelerator. The optimizations of the flat beam generation and compression at Advanced Superconducting Test Accelerator were done via start-to-end numerical simulations for bunch charges of 3.2 nC, 1.0 nC, and 20 pC at ?37??MeV. The optimized emittances of flat beams with different bunch charges were found to be 0.25???m (emittance ratio is ?400), 0.13????m, 15 nm before compression, and 0.41???m, 0.20???m, 16 nm after full compression, respectively, with peak currents as high as 5.5 kA for a 3.2?nC flat beam. These parameters are consistent with requirements needed to excite wakefields in asymmetric dielectric-lined waveguides or produce significant photon flux using small-gap micro-undulators.

Zhu, J. [Fermilab; Institute of Fluid Physics, CAEP, China; Piot, P. [Northern Illinois University; Fermilab; Mihalcea, D. [Northern Illinois University; Prokop, C. R. [Northern Illinois University

2014-08-01T23:59:59.000Z

22

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 Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensional Subject:Ground SourceHBLED Hot Testing 2014Energy

23

Temporal variability of uranium concentrations and 234 activity ratios in the Mississippi river and its tributaries  

E-Print Network [OSTI]

Temporal variability of uranium concentrations and 234 U/238 U activity ratios in the Mississippi Department of Geology and Geophysics, Texas A&M University, College Station, TX 77845, United States c/238 U activity ratios and total dissolved uranium concentrations in the Lower Mississippi River at New

24

Influence of variables on the consolidation and unconfined compressive strength of crushed salt: Technical report  

SciTech Connect (OSTI)

Eight hydrostatic compression creep tests were performed on crushed salt specimens fabricated from Avery Island dome salt. Following the creep test, each specimen was tested in unconfined compression. The experiments were performed to assess the influence of the following four variables on the consolidation and unconfined strength of crushed salt: grain size distribution, temperature, time, and moisture content. The experiment design comprised a half-fraction factorial matrix at two levels. The levels of each variable investigated were grain size distribution, uniform-graded and well-graded (coefficient of uniformity of 1 and 8); temperature 25/sup 0/C and 100/sup 0/C; time, 3.5 x 10/sup 3/s and 950 x 10/sup 3/s (approximately 60 minutes and 11 days, respectively); and moisture content, dry and wet (85% relative humidity for 24 hours). The hydrostatic creep stress was 10 MPa. The unconfined compression tests were performed at an axial strain rate of 1 x 10/sup -5/s/sup -1/. Results show that the variables time and moisture content have the greatest influence on creep consolidation, while grain size distribution and, to a somewhat lesser degree, temperature have the greatest influence on total consolidation. Time and moisture content and the confounded two-factor interactions between either grain size distribution and time or temperature and moisture content have the greatest influence on unconfined strength. 7 refs., 7 figs., 11 tabs.

Pfeifle, T.W.; Senseny, P.E.; Mellegard, K.D.

1987-01-01T23:59:59.000Z

25

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

DOE Patents [OSTI]

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.

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

1984-01-01T23:59:59.000Z

26

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

DOE Patents [OSTI]

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.

Frank, A.A.

1984-07-10T23:59:59.000Z

27

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 Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyTheTwo New Energy Storage Safety Reports NowGasoline Powertrains

28

Reducing Pausing at Rich-to-Lean Schedule Transitions: Effects of Variable-Ratio Schedules and Noncontingent Timeouts  

E-Print Network [OSTI]

-schedule component), which may maintain responding in the lean component when there is insufficient reinforcement. 4 General Introduction The Basic Problem: Pausing on FR Schedules Fixed-ratio (FR) schedules require that a certain number of responses occur.... In the context of a FR schedule, pausing may be considered counterproductive (or maladaptive) because it postpones the receipt of a reinforcer for a food-deprived organism. A host of variables affect pausing on FR schedules; for example, pausing increases as a...

Brewer, Adam Thornton

2012-08-31T23:59:59.000Z

29

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...

30

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

SciTech Connect (OSTI)

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.

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

2009-01-01T23:59:59.000Z

31

Net pay evaluation: a comparison of methods to estimate net pay and net-to-gross ratio using surrogate variables  

E-Print Network [OSTI]

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...

Bouffin, Nicolas

2009-06-02T23:59:59.000Z

32

Dynamic control of a homogeneous charge compression ignition engine  

DOE Patents [OSTI]

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.

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

2008-06-03T23:59:59.000Z

33

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...

34

Compression embedding  

DOE Patents [OSTI]

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.

1998-07-07T23:59:59.000Z

35

Compression embedding  

DOE Patents [OSTI]

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

1998-01-01T23:59:59.000Z

36

Compression embedding  

DOE Patents [OSTI]

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.

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

1998-01-01T23:59:59.000Z

37

Compression embedding  

DOE Patents [OSTI]

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

1998-03-10T23:59:59.000Z

38

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...

39

Economic and Technical Tradeoffs Between Open and Closed Cycle Vapor Compression Evaporators  

E-Print Network [OSTI]

compressor. The blowers and centrifugal compressors used for steam recompression are limited to compression ratios of around 2:1 in a single stage. This compression ratio is perfectly adequate for many applications. But if a larger driving force with a... higher compression ratio is desired. two or more compression stages must be used resulting in sig nificantly increased compressor costs. Closed Cycle Vapor Compression A schematic of a closed cycle vapor compression evaporator is shown in Figure 3...

Timm, M. L.

40

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

E-Print Network [OSTI]

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 ...

Zhao, Xin

2012-06-25T23:59:59.000Z

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


41

Chapter 22: Compressed Air Evaluation Protocol  

SciTech Connect (OSTI)

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.

Benton, N.

2014-11-01T23:59:59.000Z

42

High load operation in a homogeneous charge compression ignition engine  

DOE Patents [OSTI]

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

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

2008-12-23T23:59:59.000Z

43

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...

44

Spatial Variability in the Ratio of Interstellar Atomic Deuterium to Hydrogen. I. Observations toward delta Orionis by the Interstellar Medium Absorption Profile Spectrograph  

E-Print Network [OSTI]

Studies of the abundances of deuterium in different astrophysical sites are of fundamental importance to answering the question about how much deuterium was produced during big bang nucleosynthesis and what fraction of it was destroyed later. With this in mind, we used the Interstellar Medium Absorption Profile Spectrograph (IMAPS) on the ORFEUS-SPAS II mission to observe at a wavelength resolution of 4 km/s (FWHM) the L-delta and L-epsilon absorption features produced by interstellar atomic deuterium in the spectrum of delta Ori A. A chi-square analysis indicated that 0.96 atomic ratio of D to H, we measured the L-alpha absorption features in 57 spectra of delta Ori in the IUE archive. From our measurement of N(H I)= 1.56e20 cm^{-2}, we found that N(D I)/N(H I)= 7.4(+1.9,-1.3)e-6 (90% confidence). Our result for D/H contrasts with the more general finding along other lines of sight that D/H is approximately 1.5e-5. The underabundance of D toward delta Ori A is not accompanied by an overabundance of N or O relative to H, as one might expect if the gas were subjected to more stellar processing than usual.

Edward B. Jenkins; Todd M. Tripp; Przemyslaw R. Wozniak; Ulysses J. Sofia; G. Sonneborn

1999-01-28T23:59:59.000Z

45

A New Approach for Fingerprint Image Compression  

SciTech Connect (OSTI)

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.

Mazieres, Bertrand

1997-12-01T23:59:59.000Z

46

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

SciTech Connect (OSTI)

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.

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

2007-12-31T23:59:59.000Z

47

Sequential Compressed Sensing  

E-Print Network [OSTI]

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 ...

Malioutov, Dmitry M.

48

Compressed gas manifold  

DOE Patents [OSTI]

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.

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

2001-01-01T23:59:59.000Z

49

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.

50

Second-order Schemes for Steady Weakly Compressible Liquid Flows  

E-Print Network [OSTI]

]. Under such circumstances, the speed of sound is much larger than the velocity of the liquid, resulting-differences, such flows may display compressibility effects. Mach number, the ratio of fluid velocity to speed of sound1 Second-order Schemes for Steady Weakly Compressible Liquid Flows I. J. Keshtiban , F. Belblidia

Grant, P. W.

51

Stresses resulting from compression of bulk cotton lint fibers  

E-Print Network [OSTI]

The modulus of elasticity, Poisson's ratio and shear modulus of bulk cotton lint fibers were determined. The cotton lint was compressed in an MTS machine to a predetermined density, and the resilient forces induced by the cotton lint after being...

Chimbombi, Ezekiel Maswe

1998-01-01T23:59:59.000Z

52

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 Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment ofEnergy VictorofPolicy LanguageApplication

53

High Compression Ratio Turbo Gasoline Engine Operation Using...  

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

information * Project start date: 9012011 * Project end date: 1152015 (with no-cost extension) * Percent complete: 77% * Barriers addressed - Peak thermal efficiency...

54

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

E-Print Network [OSTI]

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

55

Hydrogen Delivery Liquefaction & Compression  

E-Print Network [OSTI]

Hydrogen Delivery Liquefaction & Compression Raymond Drnevich Praxair - Tonawanda, NY Strategic Initiatives for Hydrogen Delivery Workshop - May 7, 2003 #12;2 Agenda Introduction to Praxair Hydrogen Liquefaction Hydrogen Compression #12;3 Praxair at a Glance The largest industrial gas company in North

56

LAPPED TRANSFORMS COMPRESSION  

E-Print Network [OSTI]

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

de Queiroz, Ricardo L.

57

Fundamentals of Compressed Air Systems  

Broader source: Energy.gov [DOE]

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...

58

Modeling Compressed Turbulence  

SciTech Connect (OSTI)

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.

Israel, Daniel M. [Los Alamos National Laboratory

2012-07-13T23:59:59.000Z

59

Consider Compressed Combustion  

E-Print Network [OSTI]

, and costs. In addition, overall advantages for applications involving energy sharing, such as cogeneration are even greater. Thus, compressed combustion should be considered seriously as an economical alternative to conventional heaters, especially in energy...

Crowther, R. H.

1982-01-01T23:59:59.000Z

60

Padding with Compressed Air  

E-Print Network [OSTI]

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...

Beals, C.

2004-01-01T23:59:59.000Z

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


61

Mechanical Compression Heat Pumps  

E-Print Network [OSTI]

MECHANICAL COMPRESSION HEAT PUMPS Thomas-L. Apaloo and K. Kawamura Mycom Corporation, Los Angeles, California J. Matsuda, Mayekawa Mfg. Co., Tokyo, Japan ABSTRACT Mechanical compression heat pumping is not new in industrial applications.... In fact, industry history suggests that the theoretical concept was developed before 1825. Heat pump manufacturers gained the support of consultants and end-users when the energy crisis hit this country in 1973. That interest, today, has been...

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

62

Image compression technique  

DOE Patents [OSTI]

An image is compressed by identifying edge pixels of the image; creating a filled edge array of pixels each of the pixels in the filled edge array which corresponds to an edge pixel having a value equal to the value of a pixel of the image array selected in response to the edge pixel, and each of the pixels in the filled edge array which does not correspond to an edge pixel having a value which is a weighted average of the values of surrounding pixels in the filled edge array which do correspond to edge pixels; and subtracting the filled edge array from the image array to create a difference array. The edge file and the difference array are then separately compressed and transmitted or stored. The original image is later reconstructed by creating a preliminary array in response to the received edge file, and adding the preliminary array to the received difference array. Filling is accomplished by solving Laplace`s equation using a multi-grid technique. Contour and difference file coding techniques also are described. The techniques can be used in a method for processing a plurality of images by selecting a respective compression approach for each image, compressing each of the images according to the compression approach selected, and transmitting each of the images as compressed, in correspondence with an indication of the approach selected for the image. 16 figs.

Fu, C.Y.; Petrich, L.I.

1997-03-25T23:59:59.000Z

63

isotopic ratio | EMSL  

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

isotopic ratio isotopic ratio Leads No leads are available at this time. Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. Abstract: As a candidate...

64

Wavelet/scalar quantization compression standard for fingerprint images  

SciTech Connect (OSTI)

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.

Brislawn, C.M.

1996-06-12T23:59:59.000Z

65

Compressed Air Energy Storage System  

E-Print Network [OSTI]

/expanders are crucial for the economical viability of a Compressed Air Energy Storage (CAES) system such as the

Farzad A. Shirazi; Mohsen Saadat; Bo Yan; Perry Y. Li; Terry W. Simon

66

Compressive Rendering of Multidimensional Scenes  

E-Print Network [OSTI]

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

Sen, Pradeep

67

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...

68

Finding Structure via Compression Jason L. Hutchens  

E-Print Network [OSTI]

Structurevia Compression Jason L. Hutchens and Michael D. Alder (1998) Finding Structure via Compression. In D.M.W

69

EMSL - isotopic ratio  

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

isotopic-ratio en Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. http:www.emsl.pnl.govemslwebpublicationsmagnesium-behavior-and-structural-def...

70

Efficient Joins with Compressed Bitmap Indexes  

SciTech Connect (OSTI)

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.

Computational Research Division; Madduri, Kamesh; Wu, Kesheng

2009-08-19T23:59:59.000Z

71

Shock compression of precompressed deuterium  

SciTech Connect (OSTI)

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.

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

2011-07-31T23:59:59.000Z

72

Making Compressed Air System Decisions  

E-Print Network [OSTI]

spawned an entire industry dedicated to manufacturing equipment designed to remove moisture, lubricant, particulate and vapor contaminants from compressed air. Purification equipment, such as air dryers and filters, are used alone or in combination... to reduce the amount of contaminants in the compressed air to the desired purity. All compressed ESL-IE-96-04-32 Proceedings from the Eighteenth Industrial Energy Technology Conference, Houston, TX, April 17-18, 1996 air purification equipment requires...

Porri, R. E.

73

Interannual variability in tropospheric nitrous oxide  

E-Print Network [OSTI]

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 ...

Thompson, R. L.

74

ECG Compression: Fast Block-Sorting Compression John Halloran  

E-Print Network [OSTI]

ECG Compression: Fast Block-Sorting Compression John Halloran Department of Electrical Engineering University of Hawaii at Manoa EE 628 Fall 2008 April 13, 2010 1 Introduction Electrocardiography(ECG. Given ECG data, a patient may be diagnosed with health issues such as a heart attack or improper levels

Noble, William Stafford

75

In Proceedings of the International Symposium on High Performance Distributed Computing (HPDC), August 2001. Reducing Delay With Dynamic Selection of Compression Formats  

E-Print Network [OSTI]

archives (jar files) on average, for the networks, compression techniques, and benchmarks studied. 1). More- over, since such performance is highly variable [1, 22], se- lection of the "best" compression reduces 36% (5.5 1 #12;seconds) of total delay of compressed transfer on average, for the range of network

Sair, Suleyman

76

Data Compression with Prime Numbers  

E-Print Network [OSTI]

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.

Gordon Chalmers

2005-11-16T23:59:59.000Z

77

Edge compression manifold apparatus  

DOE Patents [OSTI]

A manifold for connecting external capillaries to the inlet and/or outlet ports of a microfluidic device for high pressure applications is provided. The fluid connector for coupling at least one fluid conduit to a corresponding port of a substrate that includes: (i) a manifold comprising one or more channels extending therethrough wherein each channel is at least partially threaded, (ii) one or more threaded ferrules each defining a bore extending therethrough with each ferrule supporting a fluid conduit wherein each ferrule is threaded into a channel of the manifold, (iii) a substrate having one or more ports on its upper surface wherein the substrate is positioned below the manifold so that the one or more ports is aligned with the one or more channels of the manifold, and (iv) device to apply an axial compressive force to the substrate to couple the one or more ports of the substrate to a corresponding proximal end of a fluid conduit.

Renzi, Ronald F. (Tracy, CA)

2007-02-27T23:59:59.000Z

78

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...

79

Energy-Optimized Lossless Compression: Rate-Variability Tradeoff  

E-Print Network [OSTI]

efficiency alone is not necessarily the best approach to minimizing total energy consumption. This conclusion is larger in this case. This motivates the problem of designing efficient compressors to minimize total energy consumption. Such energy-optimized compressors could prove useful for embedded systems

Wu, Yihong

80

Some facts concerning ratios of random variables N. Papadatos  

E-Print Network [OSTI]

)). (5) Applying (5) to g(t, w, i) = (wti , wt1-i ) we get, in view of (4), that (X, Y ) d = (Y, X), so

Papadatos, Nickos

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


81

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,...

82

Advances in compressible turbulent mixing  

SciTech Connect (OSTI)

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.

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

1992-01-01T23:59:59.000Z

83

Best compression: Reciprocating or rotary?  

SciTech Connect (OSTI)

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.

Cahill, C.

1997-07-01T23:59:59.000Z

84

The FBI compression standard for digitized fingerprint images  

SciTech Connect (OSTI)

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.

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

1996-10-01T23:59:59.000Z

85

Gas turbine power plant with supersonic shock compression ramps  

DOE Patents [OSTI]

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.

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

2008-10-14T23:59:59.000Z

86

Compressed Air 101: Getting Compressed Air to Work  

E-Print Network [OSTI]

plant energy use. Furthermore, air compression is inefficient with up to 95% of compressor power dissipated as heat. Thus even minor improvements in system operation, control strategies, and efficiency can yield large energy savings and significant non-energy...

Burke, J. J.; Bessey, E. G.

87

Simple Limits on Achieving A Quasi-Linear Magnetic Compression for an FEL Driver  

SciTech Connect (OSTI)

Free electron lasers (FEL) need a very bright electron beam in three dimensions and a high peak charge density. In order to compress an initially longer electron bunch generated from the photoinjector, magnetic bunch compression systems are widely employed. In this paper, first harmonic RF linearization and its associated requirements are reviewed. Meanwhile it is also briefly discussed what is the relation between a proper initial bunch length and main RF frequency, when a harmonic RF linearization is included. Then given a reasonable bunch compression ratio, a proper initial bunch length as a function of the main RF frequency and RF phase is estimated analytically by several approaches, assuming that no harmonic RF section is needed to linearize the energy modulation introduced during main RF acceleration, and at the same time still linearly compress the bunch length. Next the upper limit of the bunch compression ratio in a single stage is evaluated analytically. The analytical relations derived on choosing a proper initial bunch length as a function of main RF frequency are confirmed by numerical simulation. These simple limit provide rough estimations and may be beneficial for choosing bunch compression ratios in different stages of an FEL driver, especially in a first stage bunch compression where there is usually a harmonic RF linearization applied. It may also be useful in evaluating the possibility of low charge operation mode without any harmonic RF linearization, where a shorter initial bunch length can be achieved from the photoinjector.

Sun, Yipeng; /SLAC

2012-02-16T23:59:59.000Z

88

SPH compressible turbulence  

E-Print Network [OSTI]

In this paper an SPH version of the alpha turbulence model devised by Holm and his colleagues is formulated for compressible flow with a resolution that varies in space and time. The alpha model involves two velocity fields. One velocity field is obtained from the momentum equation, the other by averaging this velocity field as in the version of SPH called XSPH. The particles (fluid elements) are moved with the averaged velocity. In analogy to the continuum alpha model we obtain a particle Lagrangian from which the SPH alpha equations can be derived. The system satisfies a discrete Kelvin circulation theorem identical to that obtained with no velocity averaging. In addition, the energy, linear and angular momentum are conserved. We show that the continuum equivalent of the SPH equations are identical to the continuum alpha model, and we conjecture that they will have the same desirable features of the continuum modelincluding the reduction of energy in the high wave number modes even when the dissipation is zero. Regardless of issues concerning turbulence modelling, the SPH alpha model is a powerful extension of the XSPH algorithm which reduces disorder at short length scales and retains the constants of the motion. The SPH alpha model is simple to implement.

J. J. Monaghan

2002-04-08T23:59:59.000Z

89

Compressed gas fuel storage system  

DOE Patents [OSTI]

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.

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

2001-01-01T23:59:59.000Z

90

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearch Related InformationAciddropletgovMeasurementsIsotope ratio ARM

91

PERFORMANCE STUDY OF COMPRESSIVE SAMPLING FOR ECG SIGNAL COMPRESSION IN NOISY AND VARYING SPARSITY ACQUISITION  

E-Print Network [OSTI]

PERFORMANCE STUDY OF COMPRESSIVE SAMPLING FOR ECG SIGNAL COMPRESSION IN NOISY AND VARYING SPARSITY of compressive sam- pling (CS) for ECG compression in telecardiology, when the signal acquisition is noisy transform (TH-DWT), which is the best technique for real-time ECG compression. We show that CS is quite

Durrani, Salman

92

The wavelet/scalar quantization compression standard for digital fingerprint images  

SciTech Connect (OSTI)

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.

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

1994-04-01T23:59:59.000Z

93

Variable delivery, fixed displacement pump  

DOE Patents [OSTI]

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.

Sommars, Mark F. (Sparland, IL)

2001-01-01T23:59:59.000Z

94

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

E-Print Network [OSTI]

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.

Wang, Yihua

2013-01-01T23:59:59.000Z

95

Integrating Online Compression to Accelerate Large-Scale Data Analytics Applications  

SciTech Connect (OSTI)

Abstract—With growing dataset sizes, and as computing cycles are increasing faster than storage and wide-area bandwidths, compression appears like a promising approach for improving the performance of large-scale data analytics applications. In this context, this paper makes the following contributions. First, we develop a new compression methodology, which exploits the similarities between spatial and/or temporal neighbors in a simulation dataset, and enables high compression ratios and low decompression costs. Second, we have developed a framework that can be used to incorporate a variety of compression and decompression algorithms. This framework also supports a simple API to allow integration with an existing application or data processing middleware. Once a compression algorithm is implemented, this framework can allow multi-threaded retrieval, multi-threaded data decompression, and use of informed prefetching and caching. By integrating this framework with a data-intensive middleware, we have applied our compression methodology and framework to three applications over two datasets, including a GCRM climate model dataset. We obtained an average compression ratio of 51.68%, and up to 53.27% improvement in execution time of data analysis applications.

Bicer, T.; Yin, Jian; Chiu, David; Agrawal, Gagan; Schuchardt, Karen L.

2013-05-19T23:59:59.000Z

96

Apparatus for measuring tensile and compressive properties of solid materials at cryogenic temperatures  

DOE Patents [OSTI]

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.

Gonczy, John D. (Oaklawn, IL); Markley, Finley W. (St. Charles, IL); McCaw, William R. (Burr Ridge, IL); Niemann, Ralph C. (Downers Grove, IL)

1992-01-01T23:59:59.000Z

97

Peak power ratio generator  

DOE Patents [OSTI]

A peak power ratio generator is described for measuring, in combination with a conventional power meter, the peak power level of extremely narrow pulses in the gigahertz radio frequency bands. The present invention in a preferred embodiment utilizes a tunnel diode and a back diode combination in a detector circuit as the only high speed elements. The high speed tunnel diode provides a bistable signal and serves as a memory device of the input pulses for the remaining, slower components. A hybrid digital and analog loop maintains the peak power level of a reference channel at a known amount. Thus, by measuring the average power levels of the reference signal and the source signal, the peak power level of the source signal can be determined.

Moyer, Robert D. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

98

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,...

99

Mechanical compression attenuates normal human bronchial epithelial wound healing  

E-Print Network [OSTI]

Open Access Research Mechanical compression attenuatesto the application of mechanical compression in the presenceResults: We found that mechanical compression and scrape

Arold, Stephen P.; Malavia, Nikita; George, Steven C.

2009-01-01T23:59:59.000Z

100

Compressed Gas EHS-2200-WEB  

E-Print Network [OSTI]

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

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


101

Forecourt Storage and Compression Options  

E-Print Network [OSTI]

capital costs and maximize utilization NATURAL GAS & HYDROGEN FUELING STATION SIZING SOFTWARE Developed 510 520 530 540 Minutes Bank1 Bank2 Bank3 Cascade Banks Pressure Vs.Time (Hydrogen) #12;16 Compressor> Forecourt Storage and Compression Options DOE and FreedomCAR & Fuel Partnership Hydrogen Delivery

102

Energy Profit Ratio Compared  

SciTech Connect (OSTI)

We need more oil energy to take out oil under the ground. Limit resources make us consider other candidates of energy source instead of oil. Electricity shall be the main role more and more like electric vehicles and air conditioners so we should consider electricity generation ways. When we consider what kind of electric power generation is the best or suitable, we should not only power generation plant but whole process from mining to power generation. It is good way to use EPR, Energy Profit Ratio, to analysis which type is more efficient and which part is to do research and development when you see the input breakdown analysis. Electricity by the light water nuclear power plant, the hydrogen power plant and the geothermal power plant are better candidates from EPR analysis. Forecasting the world primly energy supply in 2050, it is said that the demand will be double of the demand in 2000 and the supply will not be able to satisfy the demand in 2050. We should save 30% of the demand and increase nuclear power plants 3.5 times more and recyclable energy like hydropower plants 3 times more. When the nuclear power plants are 3.5 times more then uranium peak will come and we will need breed uranium. I will analysis the EPR of FBR. Conclusion: A) the EPR of NPS in Japan is 17.4 and it is the best of all. B) Many countries will introduce new nuclear power plants rapidly may be 3.5 times in 2050. C) Uranium peak will happen around 2050. (author)

Amano, Osamu [2-11-1, Iwado Kita, Komae-shi, Tokyo 201-8511 (Japan)

2007-07-01T23:59:59.000Z

103

Technical Assessment: Cryo-Compressed Hydrogen Storage  

E-Print Network [OSTI]

Technical Assessment: Cryo-Compressed Hydrogen Storage for Vehicular Applications October 30, 2006 .....................................................................................................................................................................8 APPENDIX A: Review of Cryo-Compressed Hydrogen Storage Systems ......................................................................................18 APPENDIX C: Presentation to the FreedomCAR & Fuel Hydrogen Storage Technical Team

104

Compressed Gas Cylinder Safe Handling, Use and  

E-Print Network [OSTI]

Compressed Gas Cylinder Safe Handling, Use and Storage 2012 Workplace Safety and Environmental Protection #12;i College/Unit: Workplace Safety and Environmental Protection Procedure Title: Compressed Gas................................................ 4 7 General Gas Cylinder Information

Saskatchewan, University of

105

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...

106

Compressed Air Energy Storage for Offshore  

E-Print Network [OSTI]

transmitting peak power levels. A solution to these issues is a novel high-efficiency compressed air energy

Perry Y. Li; Eric Loth; Terrence W. Simon; James D. Van De Ven; Stephen E. Crane

2011-01-01T23:59:59.000Z

107

Outline Inverted File Building Compression for Inverted Files Building and Compression Techniques for Inverted  

E-Print Network [OSTI]

Outline Inverted File Building Compression for Inverted Files Building and Compression Techniques for Inverted Files Roi Blanco Dpt. Computing Science, University of A Coruna December 13, 2005 Roi Blanco Building and Compression Techniques for Inverted Files #12;Outline Inverted File Building Compression

Barreiro, Alvaro

108

ADVANCED RECIPROCATING COMPRESSION TECHNOLOGY (ARCT)  

SciTech Connect (OSTI)

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.

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

2005-12-01T23:59:59.000Z

109

Cataclysmic Variables  

E-Print Network [OSTI]

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.

Robert Connon Smith

2007-01-23T23:59:59.000Z

110

Compressed Air Audits using AIRMaster  

E-Print Network [OSTI]

&M measures. An introduction to the AIRMaster software is provided. Goals The project goals were to develop and test a method and tools to perform Compressed Air System audits. The audits should use only simple instrumentation during a relatively short... air system leaks. 2. AIRMaster Software and User's Manual. AIRMaster is a spreadsheet-based program that can model part load system operation with up to five rotary screw and reciprocating compressors operating simultaneously with varying...

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

111

Compressed air energy storage system  

DOE Patents [OSTI]

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.

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

1981-01-01T23:59:59.000Z

112

Compressive strength, plastic flow properties, and surface frictional effects of 1100, 3003 and 6061 aluminum alloys  

SciTech Connect (OSTI)

The purpose of this study is to find aluminum alloys that are effective for use as wire vacuum seals in the 800MeV particle accelerator located at the Louis Anderson Meson Physics Facility (LAMPF) in Los Alamos, NM. Three alloys, Al 1100, Al 3003, and Al 6061, are investigated under uniaxial compression to determine stresses for a given height reduction from 0 to 70 percent, and to find plastic flow and surface interaction effects. Right-circular cylindrical specimens are compressed on-end (cylindrically) and radially (for modeling as compressed wire). Aluminum 1100 and 3003 alloys are compared for length to diameter ratios of 1 and 2 for both compression types, and are then compared to results of radial compression of annealed small diameter Al 1100 wire currently used at LAMPE. The specimens are also compressed between three different platen surfaces, polished steel, etched steel, and aluminum 6061-T6, to determine effects of friction. The Al 3003 alloy exhibits 20 to 25% lower stresses at all height reductions than Al 1100 for both cylindrical and radial compression.

Pinkerton, G.W.

1993-12-31T23:59:59.000Z

113

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

E-Print Network [OSTI]

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

Soatto, Stefano

114

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

E-Print Network [OSTI]

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

Tehranipoor, Mohammad

115

Computation of Weakly-Compressible Highly-Viscous Polymeric Liquid Flows  

E-Print Network [OSTI]

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

Grant, P. W.

116

Effect of Compressibility on the Annihilation Process  

E-Print Network [OSTI]

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.

Michal Hnati?; Juha Honkonen; Tomáš Lu?ivjanský

2013-02-01T23:59:59.000Z

117

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

E-Print Network [OSTI]

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

Tsien, Roger Y.

118

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...

119

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

E-Print Network [OSTI]

on the engine consisted of a battery, two induction coils, distributor, spark indicator and spark plug. One induction coil was connected to the spark indicator on which could be read the amount of spark advance or retardation, while the other was connected... into the spark plug circuit. Fuel was supplied to the engine by gravity flow through flexible and copper tubing, a ceramic filter, and a simple float type carburetor from a gallon tank mounted on platform scales, The scales were graduated in hundredths...

Jentsch, Donald George

1951-01-01T23:59:59.000Z

120

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 Data Center Home Page on Delicious RankCombustion |Energy Usage »of Energy StrainClientDesignOfficeTheDepartmentAgreementThe Effects ofin

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


121

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 Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment(October-DecemberBasedToward a More Secure and Cleaner Energy

122

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 Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat PumpRecord ofESPC ENABLE: ECM Summary ECM IncludedEcoHouseinINDIANDepartment of

123

A Compressed Air Reduction Program  

E-Print Network [OSTI]

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...

Hawks, K. D.

124

General Compression | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision has beenFfe2fb55-352f-473b-a2dd-50ae8b27f0a6TheoreticalFuelCellGemini Solar DevelopmentCompression Jump

125

Atomic effect algebras with compression bases  

SciTech Connect (OSTI)

Compression base effect algebras were recently introduced by Gudder [Demonstr. Math. 39, 43 (2006)]. They generalize sequential effect algebras [Rep. Math. Phys. 49, 87 (2002)] and compressible effect algebras [Rep. Math. Phys. 54, 93 (2004)]. The present paper focuses on atomic compression base effect algebras and the consequences of atoms being foci (so-called projections) of the compressions in the compression base. Part of our work generalizes results obtained in atomic sequential effect algebras by Tkadlec [Int. J. Theor. Phys. 47, 185 (2008)]. The notion of projection-atomicity is introduced and studied, and several conditions that force a compression base effect algebra or the set of its projections to be Boolean are found. Finally, we apply some of these results to sequential effect algebras and strengthen a previously established result concerning a sufficient condition for them to be Boolean.

Caragheorgheopol, Dan [Department of Mathematics and Informatics, Technical University of Civil Engineering in Bucharest, 124 Lacul Tei blv., RO-020396 and 'Ilie Murgulescu' Institute of Physical Chemistry, Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest (Romania); Tkadlec, Josef [Department of Mathematics, Faculty of Electrical Engineering, Czech Technical University in Prague, 166 27 Prague (Czech Republic)

2011-01-15T23:59:59.000Z

126

Industrial Compressed Air System Energy Efficiency Guidebook.  

SciTech Connect (OSTI)

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

United States. Bonneville Power Administration.

1993-12-01T23:59:59.000Z

127

CULTURAL RATCHETING RESULTS PRIMARILY FROM SEMANTIC COMPRESSION  

E-Print Network [OSTI]

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

Bryson, Joanna J.

128

Energy efficiency improvements in Chinese compressed airsystems  

SciTech Connect (OSTI)

Industrial compressed air systems use more than 9 percent ofall electricity used in China. Experience in China and elsewhere hasshown that these systems can be much more energy efficient when viewed asa whole system and rather than as isolated components.This paper presentsa summary and analysis of several compressed air system assessments.Through these assessments, typical compressed air management practices inChina are analyzed. Recommendations are made concerning immediate actionsthat China s enterprises can make to improve compressed air systemefficiency using best available technology and managementstrategies.

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

2007-06-01T23:59:59.000Z

129

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.

130

Optimization Online - Compressed Sensing Off the Grid  

E-Print Network [OSTI]

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

Gongguo Tang

2012-09-13T23:59:59.000Z

131

High ratio recirculating gas compressor  

DOE Patents [OSTI]

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.

Weinbrecht, J.F.

1989-08-22T23:59:59.000Z

132

Modeling of homogeneous charge compression ignition (HCCI) of methane  

SciTech Connect (OSTI)

The operation of piston engines on a compression ignition cycle using a lean, homogeneous charge has many potential attractive features. These include the potential for extremely low NO{sub x} and particulate emissions while maintaining high thermal efficiency and not requiring the expensive high pressure injection system of the typical modem diesel engine. Using the HCT chemical kinetics code to simulate autoignition of methane-air mixtures, we have explored the ignition timing, burn duration, NO{sub x} production, indicated efficiency and power output of an engine with a compression ratio of 15:1 at 1200 and 2400 rpm. HCT was modified to include the effects of heat transfer. This study used a single control volume reaction zone that varies as a function of crank angle. The ignition process is controlled by varying the intake equivalence ratio and varying the residual gas trapping (RGT). RGT is internal exhaust gas recirculation which recycles both heat and combustion product species. It is accomplished by varying the timing of the exhaust valve closure. Inlet manifold temperature was held constant at 330 Kelvins. Results show that there is a narrow range of operational conditions that show promise of achieving the control necessary to vary power output while keeping indicated efficiency above 50% and NO{sub x} levels below 100 ppm.

Smith, J.R.; Aceves, S.M.; Westbrook, C.; Pitz, W.

1997-05-01T23:59:59.000Z

133

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

SciTech Connect (OSTI)

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.

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

2011-01-01T23:59:59.000Z

134

Defect Analysis of Vehicle Compressed Natural Gas  

E-Print Network [OSTI]

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

135

FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS  

E-Print Network [OSTI]

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

Baskurt, Atilla

136

Compressible fluid model for hydrodynamic lubrication cavitation  

E-Print Network [OSTI]

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

Sart, Remi

137

Compression molding of aerogel microspheres  

DOE Patents [OSTI]

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.

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

1998-03-24T23:59:59.000Z

138

Compression molding of aerogel microspheres  

DOE Patents [OSTI]

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.

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

1998-03-24T23:59:59.000Z

139

Quantum Data Compression of a Qubit Ensemble  

E-Print Network [OSTI]

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.

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

2014-10-15T23:59:59.000Z

140

Secure Compressed Reading in Smart Grids  

E-Print Network [OSTI]

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 ...

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

2012-01-01T23:59:59.000Z

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


141

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...

142

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...

143

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...

144

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...

145

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...

146

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...

147

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

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

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

148

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...

149

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

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

NJ Compressed Natural Gas Refuse Trucks, Shuttle Buses and Infrastructure NJ Compressed Natural Gas Refuse Trucks, Shuttle Buses and Infrastructure 2012 DOE Hydrogen and Fuel Cells...

150

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)...

151

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...

152

Compressed Sensing accelerated radial acquisitions for dynamic Magnetic Resonance Imaging.  

E-Print Network [OSTI]

??We present a flexible method dubbed Accelerated Radial Compressed Sensing (ARCS) which uses Compressed Sensing to reconstruct 2D and 3D radial data. Our tests on… (more)

Zwaan, I.N.

2013-01-01T23:59:59.000Z

153

High Fidelity Modeling of Premixed Charge Compression Ignition...  

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

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

154

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,...

155

New Methodologies for Analysis of Premixed Charge Compression...  

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

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

156

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

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

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

157

Apparatus for measuring tensile and compressive properties of solid materials at cryogenic temperatures  

DOE Patents [OSTI]

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.

Gonczy, J.D.; Markley, F.W.; McCaw, W.R.; Niemann, R.C.

1992-04-21T23:59:59.000Z

158

Compressed Gas Safety for Experimental Fusion Facilities  

SciTech Connect (OSTI)

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.

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

2005-05-15T23:59:59.000Z

159

Compressed Gas Safety for Experimental Fusion Facilities  

SciTech Connect (OSTI)

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.

Lee C. Cadwallader

2004-09-01T23:59:59.000Z

160

Shock compression profiles in ceramics  

SciTech Connect (OSTI)

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.

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

1996-03-01T23:59:59.000Z

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


161

PHELIX for flux compression studies  

SciTech Connect (OSTI)

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.

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

2010-06-28T23:59:59.000Z

162

Seneca Compressed Air Energy Storage (CAES) Project  

SciTech Connect (OSTI)

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.

None

2012-11-30T23:59:59.000Z

163

Compressing Propositional Refutations Using Subsumption Hasan Amjad  

E-Print Network [OSTI]

Compressing Propositional Refutations Using Subsumption Hasan Amjad University of Cambridge Computer Laboratory 15 J J Thomson Avenue, Cambridge CB3 0FD, UK Hasan.Amjad@cl.cam.ac.uk Abstract We

Miller, Alice

164

Compressive Sensing Based High Resolution Channel Estimation ...  

E-Print Network [OSTI]

carefully design its encoding and decoding steps. They cor- .... present this process by ...... [34] J. Paredes, G.Arce, and Z. Wang, “Ultra-wideband compressed sensing: ... actions on Information Theory, vol.51, no.12, p.p. 4203–

2011-09-17T23:59:59.000Z

165

Compression and Creep of Venice Lagoon Sands  

E-Print Network [OSTI]

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 ...

Sanzeni, Alex

166

Compressed Air Load Reduction Approaches and Innovations  

E-Print Network [OSTI]

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...

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

2005-01-01T23:59:59.000Z

167

Method for compression of binary data  

DOE Patents [OSTI]

The disclosed method for compression of a series of data bytes, based on LZSS-based compression methods, provides faster decompression of the stored data. The method involves the creation of a flag bit buffer in a random access memory device for temporary storage of flag bits generated during normal LZSS-based compression. The flag bit buffer stores the flag bits separately from their corresponding pointers and uncompressed data bytes until all input data has been read. Then, the flag bits are appended to the compressed output stream of data. Decompression can be performed much faster because bit manipulation is only required when reading the flag bits and not when reading uncompressed data bytes and pointers. Uncompressed data is read using byte length instructions and pointers are read using word instructions, thus reducing the time required for decompression. 5 figs.

Berlin, G.J.

1996-03-26T23:59:59.000Z

168

Understanding the Basics of Compressed Air Systems  

E-Print Network [OSTI]

, contaminated filters, conversion to electrically operated hoists, and the use of centrifugal fans or compressed air with pressure regulators to purge control cabinets. Finally, a review of compressor technologies with typical cfm, pressure ranges, and price...

Herron, D. J.

169

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

SciTech Connect (OSTI)

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)

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

2007-09-15T23:59:59.000Z

170

Lossy compression of weak lensing data  

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

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.

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

2011-06-01T23:59:59.000Z

171

Compressed Air Systems Audits - Why? And How?  

E-Print Network [OSTI]

% of the compressed air costs, most with little or no capital investment. Almost always, in the event of a capital outlay, energy savings alone afford less than one-year payback. Many energy utility companies energetically support these efforts, and some.... 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...

Kemp, H. L.

2004-01-01T23:59:59.000Z

172

NOVEL CONCEPTS FOR THE COMPRESSION OF LARGE VOLUMES OF CARBON DIOXIDE – PHASE III  

SciTech Connect (OSTI)

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.

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

2014-06-30T23:59:59.000Z

173

INTEGRATION OF WIND TURBINES WITH COMPRESSED AIR ENERGY STORAGE  

E-Print Network [OSTI]

and an unpredictable nature, can be overcome. After an overview on storage systems, the Compressed Air

I. Arsie; V. Marano; G. Rizzo; M. Moran

174

Heat pump employing optimal refrigerant compressor for low pressure ratio applications  

DOE Patents [OSTI]

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.

Ecker, Amir L. (Dallas, TX)

1982-01-01T23:59:59.000Z

175

Dynamic Time Expansion and Compression Using Nonlinear Waveguides  

DOE Patents [OSTI]

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.

Findikoglu, Alp T.; Hahn, Sangkoo F.; Jia, Quanxi

2004-06-22T23:59:59.000Z

176

Radiative Decay of Bubble Oscillations in a Compressible Fluid  

E-Print Network [OSTI]

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.

A. M. Shapiro; M. I. Weinstein

2011-01-01T23:59:59.000Z

177

Burner Designs and Controls for Variable Air Preheat Systems  

E-Print Network [OSTI]

and batch type melting operations resulting in cyclic or variable air preheat temperatures will be discussed. Fuel savings relating to the use of recuperation and various types of fuel/air ratio systems will also be discussed....

Lied, C. R.

1981-01-01T23:59:59.000Z

178

Weather-Corrected Performance Ratio  

SciTech Connect (OSTI)

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.

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

2013-04-01T23:59:59.000Z

179

Fast electron microscopy via compressive sensing  

DOE Patents [OSTI]

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.

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

2014-12-09T23:59:59.000Z

180

Techniques for optically compressing light intensity ranges  

DOE Patents [OSTI]

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten uranium in an atomic vapor laser isotope separator (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. A number of different means for compressing the intensity range are disclosed. These include the use of photogray glass, the use of a pair of interference filters, and the utilization of a new liquid crystal notch filter in combination with an interference filter. 18 figs.

Rushford, M.C.

1989-03-28T23:59:59.000Z

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


181

Improving Energy Efficiency of Compressed Air System Based on System Audit  

E-Print Network [OSTI]

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

Shanghai, Hongbo Qin; McKane, Aimee

2008-01-01T23:59:59.000Z

182

E-Print Network 3.0 - adiabatic compression heating Sample Search...  

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

Compression H2... Hydrogen Delivery Liquefaction & Compression Raymond Drnevich Praxair - Tonawanda, NY Strategic... Liquefaction Hydrogen Compression 12;3 Praxair at a...

183

E-Print Network 3.0 - adiabatic compressed air Sample Search...  

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

& Compression Summary: Hydrogen Delivery Liquefaction & Compression Raymond Drnevich Praxair - Tonawanda, NY Strategic... Liquefaction Hydrogen Compression 12;3 Praxair at a...

184

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

E-Print Network [OSTI]

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

Abbanat, Brian A.

2001-01-01T23:59:59.000Z

185

Portable and Transparent Message Compression in MPI Libraries to Improve the Performance and Scalability of Parallel Applications  

SciTech Connect (OSTI)

The goal of this project has been to develop a lossless compression algorithm for message-passing libraries that can accelerate HPC systems by reducing the communication time. Because both compression and decompression have to be performed in software in real time, the algorithm has to be extremely fast while still delivering a good compression ratio. During the first half of this project, they designed a new compression algorithm called FPC for scientific double-precision data, made the source code available on the web, and published two papers describing its operation, the first in the proceedings of the Data Compression Conference and the second in the IEEE Transactions on Computers. At comparable average compression ratios, this algorithm compresses and decompresses 10 to 100 times faster than BZIP2, DFCM, FSD, GZIP, and PLMI on the three architectures tested. With prediction tables that fit into the CPU's L1 data acache, FPC delivers a guaranteed throughput of six gigabits per second on a 1.6 GHz Itanium 2 system. The C source code and documentation of FPC are posted on-line and have already been downloaded hundreds of times. To evaluate FPC, they gathered 13 real-world scientific datasets from around the globe, including satellite data, crash-simulation data, and messages from HPC systems. Based on the large number of requests they received, they also made these datasets available to the community (with permission of the original sources). While FPC represents a great step forward, it soon became clear that its throughput was too slow for the emerging 10 gigabits per second networks. Hence, no speedup can be gained by including this algorithm in an MPI library. They therefore changed the aim of the second half of the project. Instead of implementing FPC in an MPI library, they refocused their efforts to develop a parallel compression algorithm to further boost the throughput. After all, all modern high-end microprocessors contain multiple CPUs on a single die and will undoubtedly contain even larger numbers of CPUs in the future. Hence, a compute node in a parallel system is likely to have multiple processors per interconnection link. Thus, they investigated how to best exploit multiple CPUs to compress and decompress data for a single link, i.e., they developed a parallel version of the FPC algorithm called pFPC. On a 4-core 3 GHz Xeon system, pFPC exceeds 10 gigabits per second both in compression and decompression throughput while still reaching a compression ratio of 18%, which is reasonable for their double-precision floating-point datasets. At half this throughput, it achieves a 41% compression ratio. Moreover, the algorithm scales well to four cores and promises even higher throughputs on larger machines. Additional results and a description of the pFPC algorithm have recently been published in the proceedings of the Data Compression Conference. The C source code of pFPC is also publicly available.

David Albonesi; Martin Burtscher

2009-04-17T23:59:59.000Z

186

RESEARCH ARTICLE Development and characterization of a variable turbulence  

E-Print Network [OSTI]

(7):1037­1048, 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

Lieuwen, Timothy C.

187

Desalination Using Vapor-Compression Distillation  

E-Print Network [OSTI]

and MSF, this research investigates a high-efficiency mechanical vapor-compression distillation system that employs an improved water flow arrangement. The incoming salt concentration was 0.15% salt for brackish water and 3.5% salt for seawater, whereas...

Lubis, Mirna R.

2010-07-14T23:59:59.000Z

188

Faster Compressed Dictionary Matching (extended abstract)  

E-Print Network [OSTI]

The past few years have witnessed several exciting results on compressed represen- tation of a string T that supports e±cient pattern matching, and the space complexity has been reduced to jTjHk(T)+o(jTj log ¾) bits [8, ...

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

2010-01-01T23:59:59.000Z

189

Compressed Index for Dictionary Matching (extended abstract)  

E-Print Network [OSTI]

The past few years have witnessed several exciting results on compressed represen- tation of a string T that supports e±cient pattern matching, and the space complexity has been reduced to jTjHk(T)+o(jTj log ¾) bits [8, ...

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

2008-01-01T23:59:59.000Z

190

Energy Efficiency in Compressed Air Systems  

E-Print Network [OSTI]

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

Hingorani, A.; Pavlov, A.

2010-01-01T23:59:59.000Z

191

Advanced Controls for Industrial Compressed Air Systems  

E-Print Network [OSTI]

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...

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

192

Compressive Computation in Analog VLSI Motion Sensors  

E-Print Network [OSTI]

Compressive Computation in Analog VLSI Motion Sensors Rainer A. Deutschmann1 and Oliver G. Wenisch2 analog VLSI mo- tion sensors developed in the past. We show how their pixel-parallel architecture can is best suited to perform the algorithm even at high noise levels. 1 Analog VLSI Motion Sensors Inthe past

Deutschmann, Rainer

193

Regression Cubes with Lossless Compression and Aggregation  

E-Print Network [OSTI]

, 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

Pei, Jian

194

From sideward flow to nuclear compressibility  

SciTech Connect (OSTI)

We show that the differences between the Plastic Ball and DIOGENE experiments on sideward flow make it possible to asses independently, within the transport description of collisions, the effect of density dependence and momentum dependence of the nucleon optical potential. We estimate that the nuclear compressibility [ital K] lies between 180 and 235 MeV.

Pan, Q.; Danielewicz, P. (National Superconducting Cyclotron Laboratory and Department of Physics Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States))

1993-04-05T23:59:59.000Z

195

From sideward flow to nuclear compressibility  

SciTech Connect (OSTI)

The authors use the transport model (BUU) with different optical potentials, combining density and momentum dependence with strong or weak nuclear compressibility, to simulate heavy-ion collisions. Experiment by DIOGENE allows them to show that experimental sideward flow is close to their calculations using optical potential of soft momentum- and density-dependence (Potential I), as well as calculations using optical potential of stiff pure density-dependence (Potential II). On the other hand, the Plastic Ball experiment on sideward flow, mainly due to the instrumental rejection of low transverse momentum particles, allows the authors to tell the differences between Potential I and II, with calculations using Potential I being close to the experimental data. Combining the results above, they see that only potential I with soft nuclear compressibility can describe the experimental data. The uncertainty of NN cross section in the medium leads to the uncertainty in nuclear compressibility, they estimate that the nuclear compressibility K lies between 180 and 235 MeV.

Pan, Q.; Danielewicz, P.

1993-04-01T23:59:59.000Z

196

Thickness and drainage of perfluoropolyethers under compression  

SciTech Connect (OSTI)

The Surface Forces Apparatus was used to study the compression and drainage of perfluoropolyethers (PFPE) between two flat parallel mica surfaces. In the case of Zdols and Demnum-SA, the PFPE can be squeezed out during slow compression to a final residual film one gyration diameter in thickness. This thickness remained constant up to the highest applied pressure of (is similar to)10 MPa. The residual thickness for Demnum-SA, with one active end group, was found to be approximately 40% larger than that for Zdol of the same molecular weight, with two active end groups. In contrast, Z03, with no active end groups, could be displaced completely from the contact. The dynamics of expulsion were studied by monitoring the variation of the gap width as a function of time after fast (a few milliseconds) step increase in the compressive load. It was found that Zdol behaves as the bulk liquid down to gap widths of 4 equivalent gyration diameters. A viscosity increase of more than 10 times was observed when the gap width was between 4 and 2 gyration diameters. Finally, slow compression to the maximum achievable pressure (approximately 10 MPa) led to a residual layer one gyration diameter in thickness trapped between the mica surfaces.

Xu, Lei; Ogletree, D Frank; Salmeron, Miquel; Tang, Huan; Gui, Jing

2001-01-01T23:59:59.000Z

197

Wave motions in unbounded poroelastic solids infused with compressible fluids  

E-Print Network [OSTI]

Wave motions in unbounded poroelastic solids infused with compressible fluids S. Quiligotti, G at proposing a two-scale constitutive theory of a poroelastic solid infused with an inviscid compressible fluid

198

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...

199

CO? compression for capture-enabled power systems  

E-Print Network [OSTI]

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 ...

Suri, Rajat

2009-01-01T23:59:59.000Z

200

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...

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


201

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...

202

2015 - LNG Export, Compressed Natural Gas (CNG), Re-Exports ...  

Energy Savers [EERE]

2015 - LNG Export, Compressed Natural Gas (CNG), Re-Exports & Long Term Natural Gas Applications 2015 - LNG Export, Compressed Natural Gas (CNG), Re-Exports & Long Term Natural Gas...

203

Centralized Collaborative Compressed Sensing of Wideband Spectrum for Cognitive Radios  

E-Print Network [OSTI]

1 Centralized Collaborative Compressed Sensing of Wideband Spectrum for Cognitive Radios Hessam, spectrum sensing, cognitive radio, distri- bution discontinuities, algebraic detection, wideband. I technique for cognitive radio systems which combines algebraic tools and compressive sampling techniques

Paris-Sud XI, Université de

204

Low-dimensional Models for Compression, Compressed Sensing, and Prediction of Large-Scale  

E-Print Network [OSTI]

Technological University, Singapore, 639798; nikola001@e.ntu.edu.sg, muhammad89@e.ntu.edu.sg, jdauwels@ntu) is commonly deployed to compress large traffic data sets [2], [4]­[6]. PCA provides an effective low

Jaillet, Patrick

205

Summary of Compression Testing of U-10Mo  

SciTech Connect (OSTI)

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

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

2012-10-31T23:59:59.000Z

206

Conservation Theory Process Control Using Variable Frequency Drives  

E-Print Network [OSTI]

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...

Myers, N. S.

1980-01-01T23:59:59.000Z

207

Novel Spark Plugs Improve Energy Efficiency of Compressed Natural  

E-Print Network [OSTI]

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

208

Mesh Geometry Compression for Mobile Graphics Jongseok Lee  

E-Print Network [OSTI]

technology has not caught up with the energy requirement of 3D graphics processing. Data compression canMesh Geometry Compression for Mobile Graphics Jongseok Lee POSTECH thirdeye@postech.ac.kr Sungyul--This paper presents a compression scheme for mesh geometry, which is suitable for mobile graphics. The main

Lee, Seungyong

209

Modern Compressed Air Piping Selection and Design Can Have a Great Impact on Your Compressed Air Energy Dollars  

E-Print Network [OSTI]

This paper introduces new concepts in compressed air piping, sizing, and system design beyond the conventional pipe sizing charts and standard system layout guide lines. The author shows how compressed air velocity has a very significant impact...

Van Ormer, H.

2005-01-01T23:59:59.000Z

210

Compressed Air Energy Savings: SAV-AIR Monitor and Control System and the PNW Compressed Air Challenge  

E-Print Network [OSTI]

Portland, OR Portland, OR ABSTRACT This paper presents the results from two compressed air programs supported by the Northwest Energy Efficiency Alliance (Alliance) over the last five years. In 1997 the Alliance funded the Northwest regional version...Resource Group Portland, OR COMPRESSED A[R CHALLENGE The Compressed Air Challenge (CAC) is a national collaborative that develops and provides resources to educate industrial plant operating staff on ways to increase net profits through compressed air...

Anderson, K. J.; Annen, B.; Scott, S.

211

Radial Structure of Shell Modulations Near Peak Compression of Spherical Implosions  

SciTech Connect (OSTI)

The structure of shell modulations is measured at peak compression of directly driven spherical implosions using absorption of titanium-doped layers placed at various distances of 1, 5, 7, and 9 mm from the inner surface of 20-mm-thick plastic CH shells filled with 18 atm of D3He gas. The modulations are measured using the ratios of monochromatic core images taken inside and outside of the titanium 1s-2p absorption spectral region. Peak-compression, time-integrated areal-density modulations are higher at the inner shell surface, which is unstable during the deceleration phase of an implosion with a modulation level of 59{+-}14%, The perturbations are lower in the central part of the shell, having a modulation level of 18{+-}5%. The outer surface of the shell, which is unstable during the acceleration phase of an implosion, has a modulation level of 52{+-}20%.

Smalyuk, V.A.; Dumanis, S.B.; Marshall, F.J.; Delettrez, J.A.; Meyerhofer, D.D.; Regan, S.P.; Sangster, T.C.; Yaakobi, B.; Koch, J.A.

2003-03-11T23:59:59.000Z

212

PDM performance Test Results and Preliminary Analysis: Incompressible and Compressible Fluids  

SciTech Connect (OSTI)

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.

Dreesen, D.S.; Gruenhagan, E.; Cohen, J.C.; Moran, D.W.

1999-02-01T23:59:59.000Z

213

E-Print Network 3.0 - advanced reciprocating compression Sample...  

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

Machines... Hydrogen Delivery Liquefaction & Compression Raymond Drnevich Praxair - Tonawanda, NY Strategic... Liquefaction Hydrogen Compression 12;3 Praxair at a...

214

Thermodynamic Modeling and Analysis of the Ratio of Heat to Power Based on a Conceptual CHP System  

E-Print Network [OSTI]

The CHP system not only produces electrical energy, but also produces thermal energy. An extensive analysis of the CHP market reveals that one of the most important engineering characteristics is flexibility. A variable heat-to-power ratio has...

Liu, Z.; Li, X.; Liu, Z.

2006-01-01T23:59:59.000Z

215

Compression of ground-motion data  

SciTech Connect (OSTI)

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.

Long, J.W.

1981-04-01T23:59:59.000Z

216

Compression of cooked freeze-dried carrots  

E-Print Network [OSTI]

. Reduction in volume of up to 18-fold can be obtained by com- pressing dehydrated vegetables (Rabman, 1969). During World War II, the United Kingdom produced dehydrated cabbage and carrots in compressed blocks (Gooding and Rolfe, 1967). Fairbrother (1968...-propanol at low concentration by freeze-drying carbohydrate solutions. J. of Food Sci. 37:617. Flosdorf, E. W. 1949. "Freeze-drying, " Reinhold Publishing Co. , New York. Gooding, E. B. B. and Rolfe, E. J. 1957. Some Recent Work on Dehy- dration...

Macphearson, Bruce Alan

2012-06-07T23:59:59.000Z

217

Compression mode resonances in Zr-90  

E-Print Network [OSTI]

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...

Youngblood, David H.; Lui, YW; John, B.; Tokimoto, Y.; Clark, HL; Chen, X.

2004-01-01T23:59:59.000Z

218

Combined rankine and vapor compression cycles  

DOE Patents [OSTI]

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.

Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

2005-04-19T23:59:59.000Z

219

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

SciTech Connect (OSTI)

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.

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

2014-01-01T23:59:59.000Z

220

Practical method and device for enhancing pulse contrast ratio for lasers and electron accelerators  

DOE Patents [OSTI]

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.

Zhang, Shukui; Wilson, Guy

2014-09-23T23:59:59.000Z

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


221

Abundance Ratios in Early-Type Galaxies  

E-Print Network [OSTI]

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.

Reynier Peletier

1999-04-21T23:59:59.000Z

222

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

DOE Patents [OSTI]

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.

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

2003-12-30T23:59:59.000Z

223

arXiv:cond-mat/0305430v119May2003 Shearing or Compressing a Soft Glass in 2D: Time-concentration superposition  

E-Print Network [OSTI]

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

Cicuta, Pietro

224

A Well-Balanced Scheme For Two-Fluid Flows In Variable Cross-Section ducts  

E-Print Network [OSTI]

, ) 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

Paris-Sud XI, Université de

225

What is the Chance that the Equity Premium Varies Evidence from Regressions on the Dividend-Price Ratio  

E-Print Network [OSTI]

on the Dividend-Price Ratio Jessica A. Wachter University of Pennsylvania and NBER Missaka Warusawitharana Board of predictability. When we apply our methods to the dividend-price ratio, we find that even investors who are quite confronted by the historical time series of returns and predictor variables. Correctly taking into account

Kahana, Michael J.

226

FURTHER INVESTIGATION OF THE TIME DELAY, MAGNIFICATION RATIOS, AND VARIABILITY IN THE  

E-Print Network [OSTI]

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

Hewitt, Jacqueline H.

227

Rarefactive and compressive soliton waves in unmagnetized dusty plasma with non-thermal electron and ion distribution  

SciTech Connect (OSTI)

Sagdeev's pseudo potential method is employed to study dust acoustic solitary waves in an unmagnetized plasma containing negatively charged dusts with non-thermal electron and ion. The range of parameters for the existence of solitary waves using the analytical expression of the Sagdeev potential has been found. It is observed that, depending on the values of the plasma parameters like ion to electron temperature ratio ?, non-thermal parameters ? and ?, electron to ion density ratio ?, and the value of the Mach number M, both rarefactive and compressive solitary waves may exist.

Eslami, Esmaeil, E-mail: eeslami@iust.ac.ir; Baraz, Rasoul [Department of Physics, Iran University of Science and Technology, Narmak, Tehran, 16846-13114 (Iran, Islamic Republic of)] [Department of Physics, Iran University of Science and Technology, Narmak, Tehran, 16846-13114 (Iran, Islamic Republic of)

2014-02-15T23:59:59.000Z

228

International magnetic pulse compression workshop: (Proceedings)  

SciTech Connect (OSTI)

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.

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

1991-04-01T23:59:59.000Z

229

Low emissions compression ignited engine technology  

DOE Patents [OSTI]

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.

Coleman, Gerald N. (Dunlap, IL); Kilkenny, Jonathan P. (Peoria, IL); Fluga, Eric C. (Dunlap, IL); Duffy, Kevin P. (East Peoria, IL)

2007-04-03T23:59:59.000Z

230

Coke cake behavior under compressive forces  

SciTech Connect (OSTI)

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.

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

1997-12-31T23:59:59.000Z

231

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 on Delicious Rank EERE:Year in3.pdfEnergy HealthComments MEMA:May1.docEx5.docof Energy Adverse MotorCompressed Air

232

Percutaneous Vertebroplasty for Osteoporotic Compression Fracture: Multivariate Study of Predictors of New Vertebral Body Fracture  

SciTech Connect (OSTI)

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.

Komemushi, Atsushi, E-mail: kome64@yo.rim.or.jp; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo [Kansai Medical University, Department of Radiology (Japan); Komemushi, Sadao [Kinki University, Schoool of Agriculture (Japan); Sawada, Satoshi [Kansai Medical University, Department of Radiology (Japan)

2006-08-15T23:59:59.000Z

233

Modeling ramp compression experiments using large-scale molecular dynamics simulation.  

SciTech Connect (OSTI)

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.

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)

2011-10-01T23:59:59.000Z

234

Understanding Biomass Feedstock Variability  

SciTech Connect (OSTI)

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.

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

2013-01-01T23:59:59.000Z

235

Understanding Biomass Feedstock Variability  

SciTech Connect (OSTI)

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.

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

2013-01-01T23:59:59.000Z

236

A New Compressive Imaging Camera Architecture using Optical-Domain Compression  

E-Print Network [OSTI]

for processing, to a "computa- tional signal processing" (CSP) paradigm, where analog signals are converted nonlinear techniques. 1.1. Compressive sensing CSP builds upon a core tenet of signal processing a decorrelating transform to compact a correlated signal's energy into just a few essential coefficients.1

237

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...

238

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...

239

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...

240

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

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

Land Areas Forecourt Storage and Compression Options Forecourt and Gas Infrastructure Optimization Home About the Fuel Cell Technologies Office Hydrogen Production Hydrogen...

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


241

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...

242

Advanced CFD Models for High Efficiency Compression Ignition...  

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

for high efficiency compression-ignition engines can be used to show how turbulence-chemistry interactions influence autoignition and combustion. p-19raja.pdf More Documents &...

243

VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater  

E-Print Network [OSTI]

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

Furht, Borko

244

New Methodologies for Analysis of Premixed Charge Compression...  

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

New Methodologies for Analysis of Premixed Charge Compression Ignition Engines Salvador M. Aceves, Daniel L. Flowers, J. Ray Smith, Lee Davisson, Francisco Espinosa-Loza, Tim Ross,...

245

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

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

to ensure safe use of onboard and bulk storage hydrogen and compressed natural gas tanks * Enhance domestic and international harmonization between natural gas and hydrogen...

246

Saturable inductor and transformer structures for magnetic pulse compression  

DOE Patents [OSTI]

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.

Birx, Daniel L. (Londonderry, NH); Reginato, Louis L. (Orinda, CA)

1990-01-01T23:59:59.000Z

247

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...

248

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

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

with input from Gene Berry (Lawrence Livermore National Laboratory), Tobias Brunner (BMW) and Bill Clinkscales (SCI). Technical Assessment of Cryo-Compressed Hydrogen Storage...

249

Multilayer compressive seal for sealing in high temperature devices  

DOE Patents [OSTI]

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.

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

2007-08-21T23:59:59.000Z

250

Probabilistic Analysis of the Compressibility of Soils  

E-Print Network [OSTI]

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...

Jung, Byoung C.

2010-07-14T23:59:59.000Z

251

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

SciTech Connect (OSTI)

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.

None

2010-09-13T23:59:59.000Z

252

Compression station key to Texas pipeline project  

SciTech Connect (OSTI)

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.

NONE

1996-10-01T23:59:59.000Z

253

Frequency extrapolation by nonconvex compressive sensing  

SciTech Connect (OSTI)

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.

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

2010-12-03T23:59:59.000Z

254

Compact wavefunctions from compressed imaginary time evolution  

E-Print Network [OSTI]

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.

Jarrod R. McClean; Alán Aspuru-Guzik

2014-09-25T23:59:59.000Z

255

University of Arizona Compressed Air Energy Storage  

SciTech Connect (OSTI)

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.

Simmons, Joseph; Muralidharan, Krishna

2012-12-31T23:59:59.000Z

256

Very Low Fruit:Flower Ratios in Grevillea (Proteaceae) are Independent  

E-Print Network [OSTI]

breeding systems: G. linearifolia was self-incompatible (SI = 0.003), G. sphacelata, G. mucronulata, and G.61). Intrapopulation variability in the level of self-incompatibility was high in all species but G. linearifolia-specific compatibility was compared using the self-compatibility index (SI = ratio of selfed fruit set to crossed fruit

Innes, David J.

257

8, 41994219, 2008 Study of the ratios  

E-Print Network [OSTI]

(UV) spectra of atmospheric global irradiance with the miniature fiber optic spectrometer AvaSpec-256ACPD 8, 4199­4219, 2008 Study of the ratios UV-A/UV-B from UV irradiance spectra I. Ansko et al@aai.ee) 4199 #12;ACPD 8, 4199­4219, 2008 Study of the ratios UV-A/UV-B from UV irradiance spectra I. Ansko et

Boyer, Edmond

258

VARIABILITY OF KD VALUES IN CEMENTITIOUS MATERIALS AND SEDIMENTS  

SciTech Connect (OSTI)

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).

Almond, P.; Kaplan, D.; Shine, E.

2012-02-02T23:59:59.000Z

259

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

E-Print Network [OSTI]

Williams, Compressed air energy storage: Theory, resources,study for the compressed air energy storage technology byplant for compressed air energy storage power generation,

Rutqvist, J.

2013-01-01T23:59:59.000Z

260

Porous media compressed air energy storage (PM-CAES): Theory and simulation of the coupled wellbore-reservoir system  

E-Print Network [OSTI]

of selected compressed air energy storage studes, Pacificaspects of compressed-air energy storage in aquifers, J. ofresources and compressed air energy storage (CAES), Energy,

Oldenburg, C.M.

2014-01-01T23:59:59.000Z

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


261

Characterizing excavation damaged zone and stability of pressurized lined rock caverns for underground compressed air energy storage  

E-Print Network [OSTI]

for Underground Compressed Air Energy Storage Hyung-Mok Kimperformance of compressed air energy storage (CAES) in linedcavern (LRC); Compressed air energy storage (CAES); TOUGH-

Kim, H.M.

2014-01-01T23:59:59.000Z

262

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

E-Print Network [OSTI]

Williams, Compressed air energy storage: Theory, resources,for the compressed air energy storage technology by thefor compressed air energy storage power generation, Japan

Rutqvist, J.

2013-01-01T23:59:59.000Z

263

ENG 4793: Composite Materials and Processes 1 Compression Molding  

E-Print Network [OSTI]

1 ENG 4793: Composite Materials and Processes 1 Compression Molding ver 2 ENG 4793: Composite Materials and Processes 2 ENG 4793: Composite Materials and Processes 3 ENG 4793: Composite Materials and Processes 4 Schematic of a Compression Molding Press ENG 4793: Composite Materials and Processes 5 Matched

Colton, Jonathan S.

264

Circle criterion observer for a compression system Bjrnar Bhagen  

E-Print Network [OSTI]

.gravdahl@itk.ntnu.no Abstract-- Observers for a compression system using turbo compressors are derived for a model that captures speed. Results are validated by simulations. I. MOTIVATION Compression systems using turbo compressors, centrifugal or axial, are exposed to the phenomenons of surge and rotating stall. Surge is an axisymmtrical

Gravdahl, Jan Tommy

265

Compressed Gas Cylinder Safety I. Background. Due to the nature  

E-Print Network [OSTI]

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

Suzuki, Masatsugu

266

Using Statistical Transformations to Improve Compression for Linear Decompressors  

E-Print Network [OSTI]

in the test data to reduce the number of specified bits that need to be produced by the linear decompressor described in this paper. 1. Introduction Test data compression provides a means to reduce test costs by reducing tester storage, test time, and test data bandwidth requirements. Compressing the output response

Touba, Nur A.

267

Homogeneous Charge Compression Ignition: Formulation Effect of a Diesel Fuel  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

268

Simplified Compression of Redundancy Free Trellis Sections in Turbo Decoder  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

269

Techno-economic Performance Evaluation of Compressed Air  

E-Print Network [OSTI]

PNNL-22235 Techno-economic Performance Evaluation of Compressed Air Energy Storage in the Pacific of Compressed Air Energy Storage in the Pacific Northwest BP McGrail JE Cabe CL Davidson FS Knudsen DH Bacon MD air energy storage (CAES) in the unique geologic setting of inland Washington and Oregon. The basic

270

Raw Data Compression in Computed Tomography: Noise Shaping  

E-Print Network [OSTI]

Raw Data Compression in Computed Tomography: Noise Shaping Yao Xie (team member: Adam Wang) Project.1 Background X-ray computed tomography (CT) builds on the physical principles of radiography. It uses multiple ring that has a limited data transfer rate. Compression can be used to reduce the data rate through

Xie, Yao

271

TIME-PERIODIC SOUND WAVE PROPAGATION COMPRESSIBLE EULER EQUATIONS  

E-Print Network [OSTI]

A PARADIGM FOR TIME-PERIODIC SOUND WAVE PROPAGATION IN THE COMPRESSIBLE EULER EQUATIONS BLAKE consistent with time-periodic sound wave propagation in the 3 Ã? 3 nonlinear compressible Euler equations description of shock-free waves that propagate through an oscillating entropy field without breaking or dis

272

Shock compression of low-density foams  

SciTech Connect (OSTI)

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.

Holmes, N.C.

1993-07-01T23:59:59.000Z

273

Seneca Compressed Air Energy Storage (CAES) Project  

SciTech Connect (OSTI)

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.

None

2012-11-30T23:59:59.000Z

274

Combustion dynamics in steady compressible flows  

E-Print Network [OSTI]

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.

S. Berti; D. Vergni; A. Vulpiani

2008-07-03T23:59:59.000Z

275

Quantum Bootstrapping via Compressed Quantum Hamiltonian Learning  

E-Print Network [OSTI]

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.

Nathan Wiebe; Christopher Granade; David G. Cory

2015-03-30T23:59:59.000Z

276

Variable Frequency Pump Drives  

E-Print Network [OSTI]

-frequency electric motor drive. What is happenin9 with variable frequency driven pun,ps is a classical illustration that evolution in technical products takes place not only because of changes in the processes served by these products, or because of innovations...-pole 3550 rpm squirrel caqe induction motor became available in the early 1930s that high pressure pumps operating at that speed could be buil t. And now, in the 1980s, the development of the solid-state, variable frequency electric motor drive...

Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

277

Hydro-mechanical behavior of Municipal Solid Waste subject to leachate recirculation in a large-scale compression reactor cell  

SciTech Connect (OSTI)

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.

Olivier, Franck [Environment, Energy and Waste Research Center (CREED), 291, avenue Dreyfous Ducas, 78520 Limay (France) and Laboratoire LIRIGM - Maison des Geosciences, 1381, rue de la piscine 38400 Saint-Martin d'Heres (France)]. E-mail: franck.olivier@ujf-grenoble.fr; Gourc, Jean-Pierre [Laboratoire LIRIGM - Maison des Geosciences, 1381, rue de la piscine 38400 Saint-Martin d'Heres (France)]. E-mail: gourc@ujf-grenoble.fr

2007-07-01T23:59:59.000Z

278

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

SciTech Connect (OSTI)

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.

None

2012-01-04T23:59:59.000Z

279

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

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 on Delicious RankCombustion |Energy Usage »of EnergyTheTwoVulnerabilities | Department of|VTA,anCompressionVARIABLE

280

Utilization of CO2 as cushion gas for porous media compressed air energy storage  

E-Print Network [OSTI]

design of compressed air energy storage electric powerS and Williams RH, Compressed Air Energy Storage: Theory,Porous media compressed air energy storage (PM-CAES): theory

Oldenburg, C.M.

2014-01-01T23:59:59.000Z

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


281

An experimental study on the effects of compressive stress on the fatigue crack growth of low-alloy steel  

SciTech Connect (OSTI)

A series of fatigue crack growth rate tests was conducted in order to study effects of negative stress ratio on fatigue crack growth rate of low-alloy steel in air. Four-point bend specimens were used to simulate linear stress distributions typical of pressure vessel applications. This type of testing adds to knowledge on negative stress ratio effects for low-alloy steels obtained in the past from uniform tension-compression tests. Applied bending stress range was varied over twice the yield strength. Load control was used for tests for which the stress range was less than twice the yield strength and deflection control was used for the higher stress range tests. Crack geometries were both short and long fatigue cracks started at notches and tight fatigue cracks for which crack closure could occur over the full crack face. Results are presented in terms of the stress intensity factor ratio R = K{sub MIN}/K{sub MAX}. The negative R-ratio test results were correlated to an equation of the form da/dN = C[{Delta}K/(A-R)]{sup n}, where A, C, and n are curve fitting parameters. It was found that effects of negative R-ratio on fatigue crack growth rates for even the high stress range tests could be bounded by correlating the above equation to only positive R-ratio test results and extending the resulting equation into the negative R-ratio regime.

Jones, D.P.; Hoppe, R.G. [Westinghouse Electric Corp., West Mifflin, PA (United States). Bettis Atomic Power Lab.; Hechmer, J.L. [Babcock and Wilcox Co., Barberton, OH (United States); James, B.A. [Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgy

1993-12-01T23:59:59.000Z

282

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...

283

E-Print Network 3.0 - acute compression fracture Sample Search...  

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

compression fracture Search Powered by Explorit Topic List Advanced Search Sample search results for: acute compression fracture Page: << < 1 2 3 4 5 > >> 1 1. RESERVOIR...

284

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...

285

Renewed experimentation with Ranchero flux compression genereators  

SciTech Connect (OSTI)

In the late 1990s, Los Alamos pursued a coaxial flux compression generator (FCG) concept that was described in several publications under the name 'Ranchero.' These FCGs were designed to be cost effective high current generators, and a variety of configurations were tested. The Ranchero armature is a 152 mm diameter aluminum cylinder with a 6 mm thick wall. The high explosive (HE) is detonated simultaneously on axis, and as the armature expands a factor of two, the wall thins to {approx}3 mm. At the final 300 mm diameter, the circumference is over 900 mm, and this should allow currents to be generated in the 90 MA range. No tests significantly over 50 MA have been performed but an experiment is planned. We have recently begun using Ranchero devices for a new application and we continue to improve the design. In this paper we describe recent tests of Ranchero and its subsystems. The load for our new application is an imploding aluminum liner that would deform due to the magnetic pressure applied during the initial flux loading. It will, however, implode properly when powered only during the {approx}29 {micro}s Ranchero flux compression time. This gives rise to a new system with explOSively formed fuse (EFF) opening switches and an integral closing switch that isolates the load. A capacitor bank delivers 2.8 MA to the Ranchero circuit in {approx}85 {micro}s. During this time, four parallel 63.5 mm wide EFFs, external to the coaxial system, complete the circuit. After armature motion begins, insulation which initially isolates the load is severed, connecting the load to the FCG in parallel with the EFFs. External HE charges are initiated on each of the EFFs to produce a resistance rise timed to not precede closure of the load isolation switch. The EFFs achieve significant resistance, and the flux remaining in the 191 nH generator and 3 nH transmission line is compressed to generate 30.85 MA in a {approx}12.5 nH static load. On three tests, the EFF system has operated flawlessly, and only {approx}100kA is driven back into the EFFs during peak voltage of the generator output. A test incorporating a 19.5 nH dual liner dynamic load has also been completed, and these results are also presented. Ranchero generators have been operated with armatures from 43 cm to 1.4 m long, corresponding to initial inductances from 56 to 191 nH. MHD code modeling gives better agreement with experiments using modules 43 cm long than the 1.4 m modules, and these results will also be presented.

Goforth, James H [Los Alamos National Laboratory; Herrera, Dennis H [Los Alamos National Laboratory; Tasker, Douglas G [Los Alamos National Laboratory; Torres, David T [Los Alamos National Laboratory; Atchison, W. L. [Los Alamos National Laboratory; Colgate, S. A. [Los Alamos National Laboratory; Griego, J. R. [Los Alamos National Laboratory; Guzik, J. [Los Alamos National Laboratory; Holtkamp, D. B. [Los Alamos National Laboratory; Idzorek, G. [Los Alamos National Laboratory; Kaul, A [Los Alamos National Laboratory; Kirkpatrick, R. C. [Los Alamos National Laboratory; Menikoff, R. [Los Alamos National Laboratory; Meyer, R. K. [Los Alamos National Laboratory; Oona, H. [Los Alamos National Laboratory; Reardon, P. T. [Los Alamos National Laboratory; Reinovsky, R. E. [Los Alamos National Laboratory; Rousculp, C. L. [Los Alamos National Laboratory; Sgro, A. G. [Los Alamos National Laboratory; Tabaka, L. J. [Los Alamos National Laboratory; Watt, R. G. [Los Alamos National Laboratory; Riesman, D. B. [LLNL

2010-11-08T23:59:59.000Z

286

Fission Product Ratios as Treaty Monitoring Discriminants  

SciTech Connect (OSTI)

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’.

Miley, Harry S.; Bowyer, Ted W.; Greenwood, Lawrence R.; Arthur, Richard J.

2008-05-15T23:59:59.000Z

287

Blowing Ratio Effects on Film Cooling Effectiveness  

E-Print Network [OSTI]

The research focuses on testing the film cooling effectiveness on a gas turbine blade suction side surface. The test is performed on a five bladed cascade with a blow down facility. Four different blowing ratios are used in this study, which are 0...

Liu, Kuo-Chun

2010-01-14T23:59:59.000Z

288

Vector Boson Fusion Higgs Production at the LHC - Mass Variables  

E-Print Network [OSTI]

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.

Dan Green

2005-01-12T23:59:59.000Z

289

EFFECT OF COMPRESSION ON CONDUCTIVITY AND MORPHOLOGY OF PFSA MEMBRANES  

SciTech Connect (OSTI)

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.

Kusoglu, Ahmet; Weber, Adam; Jiang, Ruichin; Gittleman, Craig

2011-07-20T23:59:59.000Z

290

Variable Crop Share Leases.  

E-Print Network [OSTI]

)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...

Sartin, Marvin; Sammons, Ray

1980-01-01T23:59:59.000Z

291

Variable depth core sampler  

DOE Patents [OSTI]

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.

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

1996-02-20T23:59:59.000Z

292

Compression induced delamination in a unidirectional graphite/epoxy composite  

E-Print Network [OSTI]

110 Vl Table LIST OF TABLES Page 1 Compression Delamination Test Results P = 19. 79 N (4, 45 lb) E* = 136. 55 GPa (19. 8E6 Psi) s 2 Compression Delamination Test Results P = 24. OZ N (5. 4 lb) E = 136. 55 GPa (19. 8E6 Psi) s 3 Compression... Involving Different Crack Surface Displacements 3 fl . P /P 4 f2 vs. Pa/Pc 5 f3 vs. Pa/Pc 6 f4 vs. Pa/Pc 7 Test Specimen 8 Specimen Geometry 9 Cure Cycle for ASl/3502 Graphite/Epoxy Panels 10 Split Laminate in the Form of a Double-Cantilever Beam...

Earley, John W.

1981-01-01T23:59:59.000Z

293

Analytical bunch compression studies for FLUTE  

E-Print Network [OSTI]

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...

Schreck, M

2014-01-01T23:59:59.000Z

294

Representation and compression of multidimensional piecewise functions using surflets  

E-Print Network [OSTI]

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 ...

Chandrasekaran, Venkat

295

Heat release effects on decaying homogeneous compressible turbulence  

E-Print Network [OSTI]

turbulence. A good understanding of high-enthalpy compressible turbulence is crucial for analyzing the flow around re-entry spacecrafts and hypersonic flight vehicles, and inside scramjet engines. One main factor affecting turbulence in these high...

Lee, Kurn Chul

2009-05-15T23:59:59.000Z

296

XML Structure Compression Mark Levene and Peter Wood  

E-Print Network [OSTI]

XML Structure Compression Mark Levene and Peter Wood Birkbeck College, University of London London WC1E 7HX, U.K. {m.levene,p.wood}@dcs.bbk.ac.uk Abstract XML is becoming the universal language

Levene, Mark

297

Outphasing Energy Recovery Amplifier With Resistance Compression for Improved Efficiency  

E-Print Network [OSTI]

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 ...

Godoy, Philip Andrew

298

Business Case for Compressed Natural Gas in Municipal Fleets  

SciTech Connect (OSTI)

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.

Johnson, C.

2010-06-01T23:59:59.000Z

299

Weak-strong clustering transition in renewing compressible flows  

E-Print Network [OSTI]

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.

Ajinkya Dhanagare; Stefano Musacchio; Dario Vincenzi

2014-11-01T23:59:59.000Z

300

Fuel effects in homogeneous charge compression ignition (HCCI) engines  

E-Print Network [OSTI]

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 ...

Angelos, John P. (John Phillip)

2009-01-01T23:59:59.000Z

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


301

Global Inference for Sentence Compression: An Integer Linear Programming Approach   

E-Print Network [OSTI]

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 ...

Clarke, James

2008-01-01T23:59:59.000Z

302

Grid adaptation for functional outputs of compressible flow simulations  

E-Print Network [OSTI]

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 ...

Venditti, David Anthony, 1973-

2002-01-01T23:59:59.000Z

303

Mission Design for Compressive Sensing with Mobile Robots  

E-Print Network [OSTI]

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 ...

Hummel, Robert

304

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.

305

Copper laser modulator driving assembly including a magnetic compression laser  

DOE Patents [OSTI]

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.

Cook, Edward G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Ball, Don G. (Livermore, CA)

1994-01-01T23:59:59.000Z

306

Correlated spectral variability in brown dwarfs  

E-Print Network [OSTI]

Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over timescales of hours. Here I report results of infrared (0.95-1.64 micron) spectrophotometric monitoring of four field L and T dwarfs spanning timescales of 0.1-5.5 hrs, the goal being to learn more about the physical nature of this variability. Spectra are analysed differentially with respect to a simultaneously observed reference source in order to remove Earth-atmospheric variations. The variability amplitude detected is typically 2-10%, depending on the source and wavelength. I analyse the data for correlated variations between spectral indices. This approach is more robust than single band or chisq analyses, because it does not assume an amplitude for the (often uncertain) noise level (although the significance test still assumes a shape for the noise power spectrum). Three of the four targets show significant evidence for correlated variability. Some of this can be associated with specific features including Fe, FeH, VO and KI, and there is good evidence for intrinsic variability in water and possibly also methan. Yet some of this variability covers a broader spectral range which would be consistent with dust opacity variations. The underlying common cause is plausibly localized temperature or composition fluctuations caused by convection. Looking at the high signal-to-noise ratio stacked spectra we see many previously identified spectral features of L and T dwarfs, such as KI, NaI, FeH, water and methane. In particular we may have detected methane absorption at 1.3-1.4 micron in the L5 dwarf SDSS 0539-0059.

C. A. L. Bailer-Jones

2007-11-28T23:59:59.000Z

307

Effect of three-dimensionality on compressible mixing  

SciTech Connect (OSTI)

Existing experimental data and hypotheses on the growth rates of compressible and incompressible turbulent shear layers are used to estimate the effect of three-dimensionality in the turbulent mixing enhancement in compressible shear flows that is critically important to the efficiency of scramjet powerplants. The general trend is found to be a decrease in growth rate with increasing three-dimensionality, excepting only the restricted regime, where the growth-rate increase is modest. 9 refs.

Papamoschou, D. (California, University, Irvine (United States))

1992-02-01T23:59:59.000Z

308

Efficiency of compressed-air systems. Final report  

SciTech Connect (OSTI)

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.

Not Available

1983-01-01T23:59:59.000Z

309

The Many Faces of a Compressed Air Audit  

E-Print Network [OSTI]

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...

Kemp, H. L.

2006-01-01T23:59:59.000Z

310

Two-phase compressibility factors for retrograde gases  

E-Print Network [OSTI]

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...

Rayes, Daniel George

1989-01-01T23:59:59.000Z

311

Hot compression process for making edge seals for fuel cells  

DOE Patents [OSTI]

A hot compression process for forming integral edge seals in anode and cade assemblies wherein the assemblies are made to a nominal size larger than a finished size, beads of AFLAS are applied to a band adjacent the peripheral margins on both sides of the assemblies, the assemblies are placed in a hot press and compressed for about five minutes with a force sufficient to permeate the peripheral margins with the AFLAS, cooled and cut to finished size.

Dunyak, Thomas J. (Blacksburg, VA); Granata, Jr., Samuel J. (South Greensburg, PA)

1994-01-01T23:59:59.000Z

312

Compression effects on pressure loss in flexible HVAC ducts  

SciTech Connect (OSTI)

A study was conducted to evaluate the effect of compression on pressure drop in flexible, spiral wire helix core ducts used in residential and light commercial applications. Ducts of 6 inches, 8 inches and 10 inches (150, 200 and 250 mm) nominal diameters were tested under different compression configurations following ASHRAE Standard 120-1999--Methods of Testing to Determine Flow Resistance of HVAC Air Ducts and Fittings. The results showed that the available published references tend to underestimate the effects of compression. The study demonstrated that moderate compression in flexible ducts, typical of that often seen in field installations, could increase the pressure drop by a factor of four, while further compression could increase the pressure drop by factors close to ten. The results proved that the pressure drop correction factor for compressed ducts cannot be independent of the duct size, as suggested by ASHRAE Fundamentals, and therefore a new relationship was developed for better quantification of the pressure drop in flexible ducts. This study also suggests potential improvements to ASHRAE Standard 120-1999 and provides new data for duct design.

Abushakra, Bass; Walker, Iain S.; Sherman, Max H.

2002-07-01T23:59:59.000Z

313

SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) 2013  

SciTech Connect (OSTI)

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.

Gordon Rueff; Lyle Roybal; Denis Vollmer

2013-01-01T23:59:59.000Z

314

Selective document image data compression technique  

DOE Patents [OSTI]

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.--(235 words)

Fu, Chi-Yung (29 Cameo Way, San Francisco, CA 94131); Petrich, Loren I. (1674 Cordoba St., #4, Livermore, CA 94550)

1998-01-01T23:59:59.000Z

315

Selective document image data compression technique  

DOE Patents [OSTI]

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.

Fu, C.Y.; Petrich, L.I.

1998-05-19T23:59:59.000Z

316

Shock compression and expansion in central collisions  

SciTech Connect (OSTI)

Physics of central symmetric reactions of heavy nuclei, in the beam energy range from few tens of MeV to a couple of GeV per nucleon, is discussed. Within transport simulations, it is shown that shock fronts perpendicular to the beam axis form in the head-on reactions. The fronts propagate into projectile and target and they separate hot compressed matter from normal matter. With an increase of the impact parameter, the angle of inclination of fronts relative to the beam axis decreases, and in-between the fronts a weak tangential discontinuity develops. Hot matter exposed to the vacuum in directions perpendicular to the shock motion (and parallel to fronts), starts to expand sideways, early within reactions. Expansion in the direction of shock motion follows, after the shocks traverse nuclei, but due to the delay does not acquire same strength. Expansion affects angular distributions and mean-energy components, and further shapes of spectra and mean energies of different particles emitted into any one direction, and also particle yields. Both the anisotropy in the expansion and a collective motion associated with the weak discontinuity, affect the magnitude of sideward flow within reaction plane. Differences in mean particle energy components in and out of the reaction plane in semicentral collisions, depend sensitively on the relative magnitude of shock speed in normal matter and speed of sound in hot matter. The missing energy, considered in the past in association with low measured pion-multiplicity in central reactions, may be identified with the energy of collective expansion.

Danielewicz, P. [Univ. of Washington, Seattle, WA (United States). Institute for Nuclear Theory]|[Michigan State Univ., East Lansing, MI (United States)

1995-01-01T23:59:59.000Z

317

aspect ratio tori: 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...

318

aspect ratio su-8: 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...

319

BAdvanced adiabatic compressed air energy storage for the article has been accepted for inclusion  

E-Print Network [OSTI]

advantages, only compressed air energy storage (“CAES”) has the storage capacity of pumped hydro, but with

Chris Bullough; Christoph Gatzen; Christoph Jakiel; Martin Koller; Andreas Nowi; Stefan Zunft; Alstom Power; Technology Centre; Leicester Le Lh

2004-01-01T23:59:59.000Z

320

Paper Number (Assigned by IFPE Staff) Compressed Air Energy Storage for Offshore Wind Turbines  

E-Print Network [OSTI]

transmitting peak power levels. A solution to these issues is a novel highefficiency compressed air energy

Perry Y. Li; Eric Loth; Terrence W. Simon; James D. Van De Ven; Stephen E. Crane

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


321

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

E-Print Network [OSTI]

. As the compressed gas cools at constant pressure in a storage reservoir, the potential energy of the gas de- creases process and enables efficient energy storage through gas compression. Current applications involving piston Gas compression Air compressor Compression efficiency a b s t r a c t A liquid piston concept

Li, Perry Y.

322

Variable Camshaft Timing Engine Control A. G. Stefanopoulou, J. S. Freudenberg, J. W. Grizzle  

E-Print Network [OSTI]

| 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

Grizzle, Jessy W.

323

Compression-induced stacking fault tetrahedra around He bubbles in Al  

SciTech Connect (OSTI)

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.

Shao, Jian-Li, E-mail: shao-jianli@iapcm.ac.cn; Wang, Pei; He, An-Min [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)

2014-10-28T23:59:59.000Z

324

Correction of Wall Adhesion Effects in the Centrifugal Compression of Strong Colloidal Gels  

E-Print Network [OSTI]

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.

Richard Buscall; Daniel R. Lester

2014-10-09T23:59:59.000Z

325

Optimisation de l'alimentation des machines rluctance variable polyphases avec inductances mutuelles  

E-Print Network [OSTI]

, the electric connections, the excitation and the machine parameters on the size-power ratio and the torque dans les systèmes à vitesse variable. Pour améliorer les performances de la machine et diminuer le161 Optimisation de l'alimentation des machines à réluctance variable polyphasées avec inductances

Paris-Sud XI, Université de

326

ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING  

E-Print Network [OSTI]

ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING in turbocharged gasoline engines with variable valve timing requires knowledge of exhaust mani- fold pressure, Pe control systems for gasoline engines rely heavily on feedforward air-fuel ratio (A/F) control to meet

Grizzle, Jessy W.

327

System using data compression and hashing adapted for use for multimedia encryption  

DOE Patents [OSTI]

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.

Coffland, Douglas R. (Livermore, CA)

2011-07-12T23:59:59.000Z

328

PHP: Constructs and Variables Introduction  

E-Print Network [OSTI]

PHP: Constructs and Variables Introduction This document describes: 1. the syntax and types of variables, 2. PHP control structures (i.e., conditionals and loops), 3. mixed-mode processing, 4. how to use one script from within another, 5. how to define and use functions, 6. global variables in PHP, 7

Vander Zanden, Brad

329

Statistical issues in Mendelian randomization: use of genetic instrumental variables for assessing causal associations  

E-Print Network [OSTI]

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...

Burgess, Stephen

2012-03-06T23:59:59.000Z

330

Energy Balance Bowen Ratio Station (EBBR) Handbook  

SciTech Connect (OSTI)

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.

Cook, DR

2011-02-23T23:59:59.000Z

331

Implications of Fast Reactor Transuranic Conversion Ratio  

SciTech Connect (OSTI)

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.

Steven J. Piet; Edward A. Hoffman; Samuel E. Bays

2010-11-01T23:59:59.000Z

332

High aspect ratio, remote controlled pumping assembly  

DOE Patents [OSTI]

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.

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

1995-11-14T23:59:59.000Z

333

Meteorological Effects on Air/Fuel Ratio  

E-Print Network [OSTI]

1. "Temperature Compensat d Air/Fuel Ratio Control on a Recuperated Furnace," by J. L. Ferri. GTE Products Corporation, Towanda, PA, lECTC '83 2. Chemical Engineers Handbook, PerTY and Chilton, 5th ed.., (McGraw Hlln, p. 12-7. 3. "Technology..., E = (100 ... 10) (ill) - 100 = 17.2% excess a . 2 Example 2 A furnace uses recuperators which prehe~t the combustion air to 1200 OF using 30 OF air. WithJlOO OF air, the preheated air temperature will be approxIjrnately 1270 OF, a 70 OF increase...

Ferri, J. L.

1984-01-01T23:59:59.000Z

334

Commissioning of helium compression system for the 12 GeV refrigerator  

SciTech Connect (OSTI)

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.

Knudsen, Peter N. [JLAB; Ganni, Venkatarao [JLAB; Dixon, Kelly D. [JLAB; Norton, Robert O. [JLAB; Creel, Jonathan D. [JLAB; Arenius, Dana M. [JLAb

2014-01-01T23:59:59.000Z

335

Modeling added compressibility of porosity and the thermomechanical response of wet porous rock  

SciTech Connect (OSTI)

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.

Rubin, M.B.; Elata, D.; Attia, A.V.

1995-06-01T23:59:59.000Z

336

Energy recovery during expansion of compressed gas using power plant low-quality heat sources  

DOE Patents [OSTI]

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.

Ochs, Thomas L. (Albany, OR); O'Connor, William K. (Lebanon, OR)

2006-03-07T23:59:59.000Z

337

Real-Time SCADA Cyber Protection Using Compression Techniques  

SciTech Connect (OSTI)

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.

Lyle G. Roybal; Gordon H Rueff

2013-11-01T23:59:59.000Z

338

Hydraulic system for a ratio change transmission  

DOE Patents [OSTI]

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.

Kalns, Ilmars (Northville, MI)

1981-01-01T23:59:59.000Z

339

Ratios of heavy hadron semileptonic decay rates  

E-Print Network [OSTI]

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.

Michael Gronau; Jonathan L. Rosner

2010-12-27T23:59:59.000Z

340

Flexible Conversion Ratio Fast Reactor Systems Evaluation  

SciTech Connect (OSTI)

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.

Neil Todreas; Pavel Hejzlar

2008-06-30T23:59:59.000Z

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


341

Seneca Compressed Air Energy Storage (CAES) Project  

SciTech Connect (OSTI)

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

None

2012-11-30T23:59:59.000Z

342

Word aligned bitmap compression method, data structure, and apparatus  

DOE Patents [OSTI]

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.

Wu, Kesheng; Shoshani, Arie; Otoo, Ekow

2004-12-14T23:59:59.000Z

343

Abundance ratios in hierarchical galaxy formation  

E-Print Network [OSTI]

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.

D. Thomas

1999-01-18T23:59:59.000Z

344

Compressive strength of concrete and mortar containing fly ash  

DOE Patents [OSTI]

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.

Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

1997-01-01T23:59:59.000Z

345

Compressive strength of concrete and mortar containing fly ash  

DOE Patents [OSTI]

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.

Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

1997-04-29T23:59:59.000Z

346

Compressive strength of concrete and mortar containing fly ash  

DOE Patents [OSTI]

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.

Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

1998-01-01T23:59:59.000Z

347

Compressive strength of concrete and mortar containing fly ash  

DOE Patents [OSTI]

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.

Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

1998-12-29T23:59:59.000Z

348

Indentation size effect and the plastic compressibility of glass  

SciTech Connect (OSTI)

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.

Smedskjaer, Morten M., E-mail: mos@bio.aau.dk [Section of Chemistry, Aalborg University, 9000 Aalborg (Denmark)

2014-06-23T23:59:59.000Z

349

A compression scheme for radio data in high performance computing  

E-Print Network [OSTI]

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.

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

2015-01-01T23:59:59.000Z

350

Compressive turbulent cascade and heating in the solar wind  

SciTech Connect (OSTI)

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.

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

2010-03-25T23:59:59.000Z

351

Negative compressibility observed in graphene containing resonant impurities  

SciTech Connect (OSTI)

We observed negative compressibility in monolayer graphene containing resonant impurities under different magnetic fields. Hydrogenous impurities were introduced into graphene by electron beam (e-beam) irradiation. Resonant states located in the energy region of {+-}0.04 eV around the charge neutrality point were probed in e-beam-irradiated graphene capacitors. Theoretical results based on tight-binding and Lifshitz models agreed well with experimental observations of graphene containing a low concentration of resonant impurities. The interaction between resonant states and Landau levels was detected by varying the applied magnetic field. The interaction mechanisms and enhancement of the negative compressibility in disordered graphene are discussed.

Chen, X. L.; Wang, L.; Li, W.; Wang, Y.; He, Y. H.; Wu, Z. F.; Han, Y.; Zhang, M. W.; Xiong, W.; Wang, N. [Department of Physics and The William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)] [Department of Physics and The William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)

2013-05-20T23:59:59.000Z

352

Benchmarking Compressed Sensing, Super-Resolution, and Filter Diagonalization  

E-Print Network [OSTI]

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.

Markovich, Thomas; Sanders, Jacob N; Aspuru-Guzik, Alan

2015-01-01T23:59:59.000Z

353

Homogeneous Charge Compression Ignition Free Piston Linear Alternator  

SciTech Connect (OSTI)

An experimental and theoretical investigation of a homogeneous charge compression ignition (HCCI) free piston powered linear alternator has been conducted to determine if improvements can be made in the thermal and conversion efficiencies of modern electrical generator systems. Performance of a free piston engine was investigated using a rapid compression expansion machine and a full cycle thermodynamic model. Linear alternator performance was investigated with a computer model. In addition linear alternator testing and permanent magnet characterization hardware were developed. The development of the two-stroke cycle scavenging process has begun.

Janson Wu; Nicholas Paradiso; Peter Van Blarigan; Scott Goldsborough

1998-11-01T23:59:59.000Z

354

Spatial compression algorithm for the analysis of very large multivariate images  

DOE Patents [OSTI]

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.

Keenan, Michael R. (Albuquerque, NM)

2008-07-15T23:59:59.000Z

355

Structural feature controlling superconductivity in compressed BaFe{sub 2}As{sub 2}  

SciTech Connect (OSTI)

Superconductivity can be induced with the application of pressure but it disappears eventually upon heavy compression in the iron-based parent compound BaFe{sub 2}As{sub 2}. Structural evolution with pressure is used to understand this behavior. By performing synchrotron X-ray powder diffraction measurements with diamond anvil cells up to 26.1?GPa, we find an anomalous behavior of the lattice parameter with a S shape along the a axis but a monotonic decrease in the c-axis lattice parameter with increasing pressure. The close relationship between the axial ratio c/a and the superconducting transition temperature T{sub c} is established for this parent compound. The c/a ratio is suggested to be a measure of the spin fluctuation strength. The reduction of T{sub c} with the further increase of pressure is a result of the pressure-driven weakness of the spin-fluctuation strength in this material.

Yang, Wenge, E-mail: wyang@ciw.edu [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); High Pressure Synergetic Consortium, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States); Jia, Feng-Jiang [Key Laboratory of Materials Physics and Center for Energy Matter in Extreme Environments, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Tang, Ling-Yun [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Department of Physics, South China University of Technology, Guangzhou 510640 (China); Tao, Qian; Xu, Zhu-An [Department of Physics, Zhejiang University, Hangzhou 310027 (China); Chen, Xiao-Jia, E-mail: xjchen@ciw.edu [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Key Laboratory of Materials Physics and Center for Energy Matter in Extreme Environments, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015 (United States)

2014-02-28T23:59:59.000Z

356

Ignition properties of n-butane and iso-butane in a rapid compression machine  

SciTech Connect (OSTI)

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)

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)

2010-02-15T23:59:59.000Z

357

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

SciTech Connect (OSTI)

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)

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

2008-04-15T23:59:59.000Z

358

Exploring the concept of compressed air energy storage (CAES) in lined rock caverns at shallow depth: A modeling study of air tightness and energy balance  

E-Print Network [OSTI]

wind- diesel-compressed air energy storage system for remotestudy for the compressed air energy storage technology bydesign of compressed air energy storage electric power

Kim, H.-M.

2012-01-01T23:59:59.000Z

359

Selection automatique de variables pertinentes  

E-Print Network [OSTI]

S´election automatique de variables pertinentes Vers la d´ecouverte de nouvelles modalit´es sensori-motrices corr´elations entre ses variables sensori-motrices afin d'apprendre `a r´esoudre sa t^ache d

Boyer, Edmond

360

Mechanically stable, high aspect ratio, multifilar, wound, ribbon-type conductor and method for manufacturing same  

DOE Patents [OSTI]

A mechanically stable, wound, multifilar, ribbon-type conductor having a cross-sectional aspect ratio which may be greater than 12:1, comprising a plurality of conductive strands wound to form a flattened helix containing a plastic strip into which the strands have been pressed so as to form a bond between the strip and the strands. The bond mechanically stabilizes the conductor under tension, preventing it from collapsing into a tubular configuration. In preferred embodiments the plastic strip may be polytetrafluoroethylene, and the conductive strands may be formed from a superconductive material. Conductors in accordance with the present invention may be manufactured by winding a plurality of conductive strands around a hollow mandrel; the cross-section of a hollow mandrel; the cross-section of the mandrel continuously varying from substantially circular to a high aspect ratio elipse while maintaining a constant circumference. The wound conductive strands are drawn from the mandrel as a multifilar helix while simultaneously a plastic strip is fed through the hollow mandrel so that it is contained within the helix as it is withdrawn from the mandrel. The helical conductor is then compressed into a ribbon-like form and the strands are bonded to the plastic strip by a combination of heat and pressure.

Cottingham, James G. (Center Moriches, NY)

1987-01-01T23:59:59.000Z

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361

The orifice expansion correction for a 50 mm line size at various diameter ratios  

SciTech Connect (OSTI)

The expansion coefficient or factor for a compressible flowmeter corrects for the change in pressure and density as the fluid is accelerated through the flowmeter. The expansion correction currently in use in the United States and also in other countries was developed over fifty years ago by Buckingham and Bean. More recent work reported by Kinghorn shows the equation currently in use to be in error. This paper describes the results of a test program to determine the expansion factors for flange-tapped sharp-edged orifices with diameter ratios between 0.242 and 0.726 in a nominal 50 mm (2 inch) line. Critical flow Venturis are used as the reference standards and dry air as the flowing fluid. The ratio of differential pressure to inlet static pressure is varied over a range of zero to about 0.2 at a constant Reynolds number. The expansion factor is determined form the apparent change in discharge coefficient at a constant Reynolds number.

Seidl, W. [Colorado Engineering Experiment Station, Inc., Nunn, CO (United States)

1995-12-31T23:59:59.000Z

362

High-Order Entropy-Compressed Text Indexes  

E-Print Network [OSTI]

We present a novel implementation of compressed su~x arrays exhibiting new tradeoffs between search time and space occupancy for a given text (or sequence) of n symbols over an alphabet E, where each symbol is encoded by lg ]E I bits. We show...

Grossi, Roberto; Gupta, Ankur; Vitter, Jeffrey Scott

2003-01-01T23:59:59.000Z

363

POLARIZATION AND COMPRESSIBILITY OF OBLIQUE KINETIC ALFVEN WAVES  

SciTech Connect (OSTI)

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.

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)

2013-04-01T23:59:59.000Z

364

On optimally partitioning a text to improve its compression  

E-Print Network [OSTI]

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}...

Ferragina, Paolo; Venturini, Rossano

2009-01-01T23:59:59.000Z

365

Direct Compressive Measurements of Individual Titanium Dioxide Nanotubes  

E-Print Network [OSTI]

Direct Compressive Measurements of Individual Titanium Dioxide Nanotubes Tolou Shokuhfar the syn- thesis of TiO2 nanotube arrays using an aqueous HF based electrolyte.5 The pH of F ion containing electrolytes was con- trolled to form nanotubes up to a few mi- crometers in length. They reported

Endres. William J.

366

STATUS OF THE NEUTRALIZED DRIFT COMPRESSION EXPERIMENT (NDCX-II)  

SciTech Connect (OSTI)

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.

Waldron, W.L.; Kwan, J.W.

2011-04-21T23:59:59.000Z

367

Pellet Production Wood Pellets are made by compressing  

E-Print Network [OSTI]

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

368

Energy Aware Lossless Data Compression Kenneth C. Barr  

E-Print Network [OSTI]

Energy Aware Lossless Data Compression by Kenneth C. Barr B.S.E. Computer Engineering University of Michigan, April 2000 Submitted to the Department of Electrical Engineering and Computer Science in partial at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY September 2002 c Massachusetts Institute of Technology 2002. All rights

369

Random Access Compressed Sensing over Fading and Noisy Communication Channels  

E-Print Network [OSTI]

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

Stojanovic, Milica

370

Test Data Compression Using Dictionaries with Selective Entries  

E-Print Network [OSTI]

-based test data compression approach for reducing test data volume in SOCs. The proposed method is based and to drive a large number of internal scan chains in the circuit under test. Therefore, it is especially suitable for a reduced pin-count and low- cost DFT test environment, where a narrow interface between

Chakrabarty, Krishnendu

371

Compression of redundancy free trellis stages in Turbo-Decoder  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

372

POSTER PRESENTATION Open Access Compressed sensing with stochastic spikes  

E-Print Network [OSTI]

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

Kreiter, Andreas K.

373

COMPRESSION OF A PLASMA COLUMN OF INFINITE ELECTROCONDUCTIVITY SITUATED  

E-Print Network [OSTI]

45 COMPRESSION OF A PLASMA COLUMN OF INFINITE ELECTROCONDUCTIVITY SITUATED IN AN EXTERNAL AXIAL velocity, ion temperature, electron temperature and plasma density is analysed. The experimental results [1. Amongst the dissipative processes we are primarily concerned here with the electron heat conductivity

Boyer, Edmond

374

DIRECT SIMULATION OF SPATIALLY EVOLVING COMPRESSIBLE TURBULENT BOUNDARY LAYERS  

E-Print Network [OSTI]

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

Erlebacher, Gordon

375

Compression of Computer Graphics Images with Image-Based Rendering  

E-Print Network [OSTI]

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

Shahabi, Cyrus

376

NUMERICAL INVESTIGATION OF CAVITATION IN MULTI-DIMENSIONAL COMPRESSIBLE FLOWS  

E-Print Network [OSTI]

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

377

Ch. 15 Wavelet-Based Compression The Wavelet Transform  

E-Print Network [OSTI]

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

Fowler, Mark

378

Densities and Compressibilities of Chiral Molecules in the Liquid State  

E-Print Network [OSTI]

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

Baltisberger, Jay H.

379

Improvements to the Block Sorting Text Compression Algorithm  

E-Print Network [OSTI]

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

Fenwick, Peter

380

Experiments with a Block Sorting Text Compression Algorithm  

E-Print Network [OSTI]

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

Fenwick, Peter

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


381

Compressive Strength of Gamma-Irradiated Polymer Concrete  

E-Print Network [OSTI]

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

North Texas, University of

382

Novel Compression and Fueling Apparatus to Meet Hydrogen  

E-Print Network [OSTI]

compressor concept involving compression of hydrogen with a "liquid piston" with little temperature rise that are available commercially Cost increases, but cost per kg of delivered hydrogen decreases slightly 700 barg delivers 71% more hydrogen for a similar sized vehicle tank #12;8 Novel Compressor Targets: ­ Prototype

383

Method for curing polymers using variable-frequency microwave heating  

DOE Patents [OSTI]

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

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

1998-02-24T23:59:59.000Z

384

Method for curing polymers using variable-frequency microwave heating  

DOE Patents [OSTI]

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

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

1998-01-01T23:59:59.000Z

385

GLOBAL STABILITY STUDY OF THE ULTRALOW ASPECT RATIO TOKAMAK,  

E-Print Network [OSTI]

generated with aspect ratios as low as 1.1. In this extreme limit the transition of the spheromak (qedge= 0] is similar to the spheromak [5]in its strong paramagnetism and magnetic helical pitch. As the aspect ratio

386

Ultra-short nacelles for low fan pressure ratio propulsors  

E-Print Network [OSTI]

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 ...

Peters, Andreas, Ph. D. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

387

BUILDING EFFECTIVENESS COMMUNICATION RATIOS FOR IMPROVED BUILDING LIFE CYCLE MANAGEMENT  

E-Print Network [OSTI]

BUILDING EFFECTIVENESS COMMUNICATION RATIOS FOR IMPROVED BUILDING LIFE CYCLE MANAGEMENT Elmer building energy performance assessment frameworks, quantifying and categorising buildings post occupancy a performance-based strategy utilising building effectiveness communication ratios stored in Building

388

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...

389

Analysis of combustion in a small homogeneous charge compression assisted ignition engine  

E-Print Network [OSTI]

characteristics to homogeneous charge compression ignition (HCCI) engines. Difficulties such as unknown ignition.raine@auckland.ac.nz geneous charge compression ignition (HCCI) engines. JER03805 © IMechE 2006 Int. J. Engine Res. Vol. 7 #12

390

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

E-Print Network [OSTI]

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 ...

Scaringe, Robert J. (Robert Joseph)

2009-01-01T23:59:59.000Z

391

3D microstructure modeling of compressed fiber-based Gerd Gaiselmanna,  

E-Print Network [OSTI]

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

Schmidt, Volker

392

Optical, electronic, and dynamical phenomena in the shock compression of condensed matter  

E-Print Network [OSTI]

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 ...

Reed, Evan J. (Evan John), 1976-

2003-01-01T23:59:59.000Z

393

E-Print Network 3.0 - af compressed air Sample Search Results  

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

6 Page 1 of 8 2011-xx-xxxx Summary: Page 1 of 8 2011-xx-xxxx Improving Compressed Air Energy Efficiency in Automotive Plants Nasr... are typically large users of compressed...

394

EXTRACTION COMPRESSION AND ACCELERATION OF HIGH LINE CHARGE DENSITY ION BEAMS  

E-Print Network [OSTI]

on compression of heavy ion beams for creating high energyet al, “Highly Compressed Ion Beams for High Energy DensityPulsed Solenoid for Intense Ion Beam Transport,” these Proc:

Henestroza, E.

2008-01-01T23:59:59.000Z

395

Effects of electrode compression on the performance of a solid polymer electrolyte fuel cell  

E-Print Network [OSTI]

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...

Del Campo, Christopher Scott

1997-01-01T23:59:59.000Z

396

1000 JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 14, NO. 5, OCTOBER 2005 Incompressible and Compressible Flows Through  

E-Print Network [OSTI]

, discharge coefficient, in- compressible and compressible flows, microfluidics, microorifice, size effects. I. INTRODUCTION MICROFLUIDIC systems are becoming increasingly popular and finding widespread applications dispensing contraptions, DNA microarrays, genomics, microfluidic systems have recorded exponential growth

Peles, Yoav

397

RATE OF STRAIN TENSOR STATISTICS IN COMPRESSIBLE HOMOGENEOUS G. Erlebacher 1 , S. Sarkar 1  

E-Print Network [OSTI]

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

Erlebacher, Gordon

398

The effects of plasticization and storage on quality of freeze-dried and compressed carrot bars  

E-Print Network [OSTI]

of this study were: To evaluate the effects of selected plasticizing methods on quality of stored freeze-dried compressed carrot cubes. To evaluate the effects of storage temperature on quality of freeze-dried compressed carrot cubes. To subjectively... carrots. than for those which had not been compressed before storage. Retention was much lower for compressed carrots packed in air compared to those packed in an inert gas or in vacuum (Hendel, 1973). Subjective Analysis Although taste panel...

Greaves, Donald William

1978-01-01T23:59:59.000Z

399

3D compression: from A to Zip: a first complete example THOMAS LEWINER  

E-Print Network [OSTI]

the design of compression schemes adapted to specific class of models. The recent launch of Google Sketch'up

Lewiner, Thomas (Thomas Lewiner)

400

Rate-Distortion-Optimized Predictive Compression of Dynamic 3D Mesh Sequences  

E-Print Network [OSTI]

on recent static mesh compression advances can be found in [2]. An important pre-condition for successful

Eisert, Peter

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


401

Quantum information with modular variables  

E-Print Network [OSTI]

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.

A. Ketterer; S. P. Walborn; A. Keller; T. Coudreau; P. Milman

2014-06-24T23:59:59.000Z

402

ME 360L Compressible Flow and Turbomachinery ABET EC2000 syllabus  

E-Print Network [OSTI]

ME 360L ­ Compressible Flow and Turbomachinery Page 1 ABET EC2000 syllabus ME 360L ­ Compressible Flow and Turbomachinery Fall 2009 Required or Elective: Elective 2008-2010 Catalog Data: Positive Assignments: None #12;ME 360L ­ Compressible Flow and Turbomachinery Page 2 ABET EC2000 syllabus Laboratory

Ben-Yakar, Adela

403

Planning and Installation Guide: North Carolina Compressed Natural Gas Fueling Stations  

E-Print Network [OSTI]

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

404

A Low-power, Low-memory System for Wavelet-based Image Compression  

E-Print Network [OSTI]

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

Walker, James S.

405

Extracting Constitutive Stress-Strain Behavior of Microscopic Phases by Micropillar Compression  

SciTech Connect (OSTI)

The manuscript describes how micropillar compression technique can be used to perform uniaxial compression tests within individual grains so as to generate local-scale constitutive behavior which, otherwise cannot be ascertained from the conventional macroscale compression test techniques. The manuscript uses steel and magnesium alloys as an example. A portion of the magnesium work was performed at PNNL.

Williams, J. J.; Walters, Jennifer; Wang, Mingyue; Chawla, N.; Rohatgi, Aashish

2013-02-01T23:59:59.000Z

406

COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES  

E-Print Network [OSTI]

COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES Dominique materials, flywheels, pumped hydro (PH), superconducting magnetic energy storage (SMES) and compressed air-grid alternative to the large-scale compressed air energy storage systems we propose to examine the viability

Deymier, Pierre

407

DRAFT: NONLINEAR CONTROLLER DESIGN WITH BANDWIDTH CONSIDERATION FOR A NOVEL COMPRESSED AIR ENERGY STORAGE SYSTEM  

E-Print Network [OSTI]

regulation and gen- erator power tracking for a Compressed Air Energy Storage (CAES) system, a nonlinearDRAFT: NONLINEAR CONTROLLER DESIGN WITH BANDWIDTH CONSIDERATION FOR A NOVEL COMPRESSED AIR ENERGY available wind power in normal situations. Storing energy in high pressure compressed air is attractive

Li, Perry Y.

408

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

E-Print Network [OSTI]

compressor is the critical part of a Compressed Air En- ergy Storage (CAES) system. Efficient and fast and expansion has many applications in pneumatic and hydraulic systems, including in the Compressed Air Energy CAES system, high pressure (20-30MPa) compressed air is stored in a dual chamber storage vessel

Li, Perry Y.

409

Fractal Volume Compression Wayne O. Cochran John C. Hart Patrick J. Flynn  

E-Print Network [OSTI]

Fractal Volume Compression Wayne O. Cochran John C. Hart Patrick J. Flynn School of Electrical@eecs.wsu.edu 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

410

Partial Encryption of Compressed Images and Videos \\Lambda Howard Cheng y and Xiaobo Li z  

E-Print Network [OSTI]

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

Cheng, Howard

411

DIRECT NUMERICAL SIMULATION OF COMPRESSIBLE TRANSITION: AN OVERVIEW M.Y. Hussaini and G. Erlebacher  

E-Print Network [OSTI]

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

Erlebacher, Gordon

412

Wavelet Compression of ECG Signals by JPEG2000 Ali Bilgin1  

E-Print Network [OSTI]

Wavelet Compression of ECG Signals by JPEG2000 Ali Bilgin1 , Michael W. Marcellin1 , and Maria I codec can be used to compress electrocardiogram (ECG) data. Experiments using the MIT-BIH arrhythmia database illustrate that the proposed approach outperforms many existing ECG compression schemes

Bilgin, Ali

413

ENSEMBLE VARIABILITY OF NEAR-INFRARED-SELECTED ACTIVE GALACTIC NUCLEI  

SciTech Connect (OSTI)

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.

Kouzuma, S. [School of International Liberal Studies, Chukyo University, Toyota 470-0393 (Japan); Yamaoka, H., E-mail: skouzuma@lets.chukyo-u.ac.jp, E-mail: yamaoka@phys.kyushu-u.ac.jp [Department of Physics, Kyushu University, Fukuoka 812-8581 (Japan)

2012-03-01T23:59:59.000Z

414

An experimental and modeling study of iso-octane ignition delay times under homogeneous charge compression ignition conditions  

SciTech Connect (OSTI)

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.

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)

2005-08-01T23:59:59.000Z

415

TECHNOLOGIES TO ENHANCE THE OPERATION OF EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE  

SciTech Connect (OSTI)

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

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

2006-05-31T23:59:59.000Z

416

Variable metric conjugate gradient methods  

SciTech Connect (OSTI)

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.

Barth, T.; Manteuffel, T.

1994-07-01T23:59:59.000Z

417

Abstract--Heart rate variability (HRV) is frequently used to measure autonomic nervous system (ANS) activity. However,  

E-Print Network [OSTI]

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

418

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...

419

Image compression/decompression based on mathematical transform, reduction/expansion, and image sharpening  

DOE Patents [OSTI]

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.

Fu, C.Y.; Petrich, L.I.

1997-12-30T23:59:59.000Z

420

Shock compression experiments on Lithium Deuteride single crystals.  

SciTech Connect (OSTI)

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.

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

2014-10-01T23:59:59.000Z

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


421

Proton radiography of a shock-compressed target  

SciTech Connect (OSTI)

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.

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

2010-07-15T23:59:59.000Z

422

Frequency shift measurement in shock-compressed materials  

DOE Patents [OSTI]

A method is disclosed for determining molecular vibrational frequencies in shock-compressed transparent materials. A single laser beam pulse is directed into a sample material while the material is shock-compressed from a direction opposite that of the incident laser beam. A Stokes beam produced by stimulated Raman scattering is emitted back along the path of the incident laser beam, that is, in the opposite direction to that of the incident laser beam. The Stokes beam is separated from the incident beam and its frequency measured. The difference in frequency between the Stokes beam and the incident beam is representative of the characteristic frequency of the Raman active mode of the sample. Both the incident beam and the Stokes beam pass perpendicularly through the stock front advancing through the sample, thereby minimizing adverse effects of refraction.

Moore, D.S.; Schmidt, S.C.

1984-02-21T23:59:59.000Z

423

Ultrafast electron diffraction with radio-frequency compressed electron pulses  

SciTech Connect (OSTI)

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.

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)

2012-08-20T23:59:59.000Z

424

Shock compression of liquid helium to 56 GPa (560 kbar)  

SciTech Connect (OSTI)

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.

Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Trainor, R.J.; Governo, G.K.; Ross, M.; Young, D.A.

1984-09-24T23:59:59.000Z

425

Application of energy release rate principles to compression debonding  

E-Print Network [OSTI]

analyzed. An experimental program employing a polymethylmethacrylate (PMMA) model system was conducted to verify the proposed analytical technique. The model system consisted of a symmetrical beam-column arrangement subjected simultaneously to axial... to axial compressive P and synusetrical side loads P as illustrated in a s Figure 4b. PMMA was selected as the model system material for this investi- gation because it is a clear glassy thermoplastic which enables one to record debond propagation as a...

Poniktera, Christopher Dale

1980-01-01T23:59:59.000Z

426

Costs Associated With Compressed Natural Gas Vehicle Fueling Infrastructure  

SciTech Connect (OSTI)

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.

Smith, M.; Gonzales, J.

2014-09-01T23:59:59.000Z

427

Active high-power RF switch and pulse compression system  

DOE Patents [OSTI]

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.

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

1998-01-01T23:59:59.000Z

428

Shockless compression and release behavior of beryllium to 110?GPa  

SciTech Connect (OSTI)

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.

Brown, J. L.; Knudson, M. D.; Alexander, C. S.; Asay, J. R. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

2014-07-21T23:59:59.000Z

429

Low-pressure-ratio regenerative exhaust-heated gas turbine  

SciTech Connect (OSTI)

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.

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

1991-01-01T23:59:59.000Z

430

Multiple-Zone Variable Refrigerant Flow System Modeling and Equipment Performance Mapping  

SciTech Connect (OSTI)

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.

Shen, Bo [ORNL] [ORNL; Rice, C Keith [ORNL] [ORNL

2012-01-01T23:59:59.000Z

431

aerosol ratio program: Topics by E-print Network  

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

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...

432

Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From...  

Open Energy Info (EERE)

boiling or by isotopic exchange at low waterrock ratios in new fractures. The mineralogy and apparent 18O enrichments of hydrothermal fracture-filling minerals are...

433

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

SciTech Connect (OSTI)

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)

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

2007-05-15T23:59:59.000Z

434

V. Havran & J. Filip & K. Myszkowski / Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization Bidirectional Texture Function Compression Based on  

E-Print Network [OSTI]

and illumination dependent texels into a set of multidimensional conditional probability density functionsV. Havran & J. Filip & K. Myszkowski / Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization V

Havran, Vlastimil

435

In-situ neutron diffraction of LaCoO{sub 3} perovskite under uniaxial compression. II. Elastic properties  

SciTech Connect (OSTI)

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.

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: Nina.Orlovskaya@ucf.edu [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Chen, Yan [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Chemical and Engineering Materials Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); 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)

2014-07-07T23:59:59.000Z

436

Evidence for Two Distinct Morphological Classes of Gamma-Ray Bursts from their Short Timescale Variability  

E-Print Network [OSTI]

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.

D. Q. Lamb; C. Graziani; I. A. Smith

1993-06-15T23:59:59.000Z

437

IEA Workshop 59 Shape and Aspect Ratio Optimization for  

E-Print Network [OSTI]

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

438

Operating Reserves and Variable Generation  

SciTech Connect (OSTI)

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

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

2011-08-01T23:59:59.000Z

439

White dwarf masses in cataclysmic variables  

E-Print Network [OSTI]

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...

Wijnen, T P G; Schreiber, M R

2015-01-01T23:59:59.000Z

440

Reversible compression of an optical piston through Kramers dynamics  

E-Print Network [OSTI]

We study the reversible crossover between stable and bistable phases of an over-damped Brownian bead inside an optical piston. The interaction potentials are solved developing a method based on Kramers' theory that exploits the statistical properties of the stochastic motion of the bead. We evaluate precisely the energy balance of the crossover. We show that the deformation of the optical potentials induced by the compression of the piston is related to a production of heat which measures the non-adiabatic character of the crossover. This reveals how specific thermodynamic processes can be designed and controlled with a high level of precision by tailoring the optical landscapes of the piston.

Schnoering, Gabriel

2015-01-01T23:59:59.000Z

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


441

Coherent structures in compressible free-shear-layer flows  

SciTech Connect (OSTI)

Large scale coherent structures are intrinsic fluid mechanical characteristics of all free-shear flows, from incompressible to compressible, and laminar to fully turbulent. These quasi-periodic fluid structures, eddies of size comparable to the thickness of the shear layer, dominate the mixing process at the free-shear interface. As a result, large scale coherent structures greatly influence the operation and efficiency of many important commercial and defense technologies. Large scale coherent structures have been studied here in a research program that combines a synergistic blend of experiment, direct numerical simulation, and analysis. This report summarizes the work completed for this Sandia Laboratory-Directed Research and Development (LDRD) project.

Aeschliman, D.P.; Baty, R.S. [Sandia National Labs., Albuquerque, NM (United States). Engineering Sciences Center; Kennedy, C.A.; Chen, J.H. [Sandia National Labs., Livermore, CA (United States). Combustion and Physical Sciences Center

1997-08-01T23:59:59.000Z

442

Compressed air energy storage technology program. Annual report for 1980  

SciTech Connect (OSTI)

All of the major research funded under the Compressed Air Energy Storage Technology Program during the period March 1980 to March 1981 is described. This annual report is divided into two segments: Reservoir Stability Studies and Second-Generation Concepts Studies. The first represents research performed to establish stability criteria for CAES reservoirs while the second reports progress on research performed on second-generation CAES concepts. The report consists of project reports authored by research engineers and scientists from PNL and numerous subcontractors including universities, architect-engineering, and other private firms.

Kannberg, L.D.

1981-06-01T23:59:59.000Z

443

Real time electrocardiographic data compression using Walsh functions  

E-Print Network [OSTI]

been used by pre- vious investigators for data compression are Fourier, Haar, Discrete Cosine, Karhunen-Loe've (6) and Welsh (7). These transformations can be calculated by equation 2 which has approximately N operations. The Cooley-Tukey algorithm... (8) is much faster to compute having only NeLog2(N) operations and can be used on the Fourier, Haar, and Welsh transformations. The Fourier transform uses the set of exponental functions defined by the Fourier series as the orthogonal basis. Un...

Jank, Philip Charles

1982-01-01T23:59:59.000Z

444

Controlling And Operating Homogeneous Charge Compression Ignition (Hcci) Engines  

DOE Patents [OSTI]

A Homogeneous Charge Compression Ignition (HCCI) engine system includes an engine that produces exhaust gas. A vaporization means vaporizes fuel for the engine an air induction means provides air for the engine. An exhaust gas recirculation means recirculates the exhaust gas. A blending means blends the vaporized fuel, the exhaust gas, and the air. An induction means inducts the blended vaporized fuel, exhaust gas, and air into the engine. A control means controls the blending of the vaporized fuel, the exhaust gas, and the air and for controls the inducting the blended vaporized fuel, exhaust gas, and air into the engine.

Flowers, Daniel L. (San Leandro, CA)

2005-08-02T23:59:59.000Z

445

Wave motions in unbounded poroelastic solids infused with compressible fluids  

E-Print Network [OSTI]

Looking at rational solid-fluid mixture theories in the context of their biomechanical perspectives, this work aims at proposing a two-scale constitutive theory of a poroelastic solid infused with an inviscid compressible fluid. The propagation of steady-state harmonic plane waves in unbounded media is investigated in both cases of unconstrained solid-fluid mixtures and fluid-saturated poroelastic solids. Relevant effects on the resulting characteristic speed of longitudinal and transverse elastic waves, due to the constitutive parameters introduced, are finally highlighted and discussed.

Quiligotti, S; dell'Isola, F

2010-01-01T23:59:59.000Z

446

Simulation study of two-stroke cycle compression ignition engines  

E-Print Network [OSTI]

An analytical model of a &wo-strok& rycl&, r?iprocating, compression-ignition engine fueled with either diesel fuel or dry par&i& le coal fuel was developed to simulate three different two-stroke &. y& l?ngines (similar to three commercial engines.... The submodels developed were for the & I lind& r gas propert irs and for & agin& processes such as combustion, heat transfer. intake and exhaust How, scavenging and work. Diesel combustion was simulated hy?sing a correlation to rno&lel the total heat release...

Kishan, Sandeep

1985-01-01T23:59:59.000Z

447

A correlation of rock compressibility with temperature and pressure  

E-Print Network [OSTI]

reservoir rocks to higher temperatures. Tests were conducted on 17 specimens cut from 5 sandstone cores and 0 4 specimens cut from one limestone core at temperatures of 76 F, 0 0 0 200 F, 300 F, and 400 F and at pressures ranging from 100-14, 000 0 psi.... The net change in 0 0 pore volume from 100-14, 000 psi ranges between 4. 0 /o and 9. 6 /o 0 0 at room temperature and 5. 1 ? 14. 1 /o at 400 F. A definite trend was established between pore volume compressibility and porosity of the specimens tested...

Choudhary, Bijoy Kumar

1967-01-01T23:59:59.000Z

448

Exhaust gas recirculation in a homogeneous charge compression ignition engine  

DOE Patents [OSTI]

A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

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

2008-05-27T23:59:59.000Z

449

Compressed Natural Gas and Hydrogen Fuels Workshop | 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 on Delicious Rank EERE:Year in Review: Top FiveDepartment ofCarrieofPropertyEnergyWorkshopCompressed Natural Gas and

450

Compressed/Liquid Hydrogen Tanks | 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 on Delicious Rank EERE:Year in Review: Top FiveDepartment ofCarrieofPropertyEnergyWorkshopCompressed Natural Gas

451

In-situ neutron diffraction of LaCoO{sub 3} perovskite under uniaxial compression. I. Crystal structure analysis and texture development  

SciTech Connect (OSTI)

The dynamics of texture formation, changes in crystal structure, and stress accommodation mechanisms have been studied in perovskite-type R3{sup ¯}c rhombohedral LaCoO{sub 3} during uniaxial compression using in-situ neutron diffraction. The in-situ neutron diffraction revealed the complex crystallographic changes causing the texture formation and significant straining along certain crystallographic directions during compression, which are responsible for the appearance of hysteresis and non-linear ferroelastic deformation in the LaCoO{sub 3} perovskite. The irreversible strain after the first loading was connected with the appearance of non-recoverable changes in the intensity ratio of certain crystallographic peaks, causing non-reversible texture formation. However, in the second loading/unloading cycle, the hysteresis loop was closed and no further irrecoverable strain appeared after deformation. The significant texture formation is responsible for an increase in the Young's modulus of LaCoO{sub 3} at high compressive stresses, ranging from 76?GPa at the very beginning of the loading to 194?GPa at 900?MPa at the beginning of the unloading curve.

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

2014-07-07T23:59:59.000Z

452

Motion planning for experimental air path control of a variable-valve-timing spark ignition engine  

E-Print Network [OSTI]

to driveability problems) and on the fuel/air ratio (FAR) (leading to pollution peaks). To compensateMotion planning for experimental air path control of a variable-valve-timing spark ignition engine Syste´mes, Mines-ParisTech 60, bd St Michel, 75272 Paris, France a r t i c l e i n f o Article history

453

Variable Camshaft Timing Engine Control A. G. Stefanopoulou, J. S. Freudenberg, J. W. Grizzle  

E-Print Network [OSTI]

| Multivariable Feedback Control, Air-to-Fuel Ratio, Emissions, Pollution Control, Internal Combustion Engines. I and Computer Science, University of Michigan an internal combustion engine to reduce feedgas emis- sions1 Variable Camshaft Timing Engine Control A. G. Stefanopoulou, J. S. Freudenberg, J. W. Grizzle

Stefanopoulou, Anna

454

Prominence seismology using the period ratio of transverse thread oscillations  

E-Print Network [OSTI]

The ratio of the period of the fundamental mode to that of the first overtone of kink oscillations, from here on the "period ratio", is a seismology tool that can be used to infer information about the spatial variation of density along solar magnetic flux tubes. The period ratio is 2 in longitudinally homogeneous thin tubes, but it differs from 2 due to longitudinal inhomogeneity. In this paper we investigate the period ratio in longitudinally inhomogeneous prominence threads and explore its implications for prominence seismology. We numerically solve the two-dimensional eigenvalue problem of kink oscillations in a model of a prominence thread. We take into account three nonuniform density profiles along the thread. In agreement with previous works that used simple piecewise constant density profiles, we find that the period ratio is larger than 2 in prominence threads. When the ratio of the central density to that at the footpoints is fixed, the period ratio depends strongly on the form of the density profi...

Soler, R; Ballester, J L

2015-01-01T23:59:59.000Z

455

The Prospects of Alternatives to Vapor Compression Technology for Space Cooling and Food Refrigeration Applications  

SciTech Connect (OSTI)

Five alternatives to vapor compression technology were qualitatively evaluated to determine their prospects for being better than vapor compression for space cooling and food refrigeration applications. The results of the assessment are summarized in the report. Overall, thermoacoustic and magnetic technologies were judged to have the best prospects for competing with vapor compression technology, with thermotunneling, thermoelectric, and thermionic technologies trailing behind in that order.

Brown, Daryl R.; Dirks, James A.; Fernandez, Nicholas; Stout, Tyson E.

2010-03-31T23:59:59.000Z

456

X-ray Raman compression via two-stream instability in dense plasmas  

E-Print Network [OSTI]

A Raman compression scheme suitable for x-rays, where the Langmuir wave is created by an intense beam rather than the pondermotive potential between the seed and pump pulses, is proposed. The required intensity of the seed and pump pulses enabling the compression could be mitigated by more than a factor of 100, compared to conventionally available other Raman compression schemes. The relevant wavelength of x-rays ranges from 1 to 10 nm.

S. Son; Sung Joon Moon

2011-03-27T23:59:59.000Z

457

Permeability anisotropy and resistivity anisotropy of mechanically compressed mudrocks  

E-Print Network [OSTI]

Permeability anisotropy (the ratio of the horizontal to vertical permeability) is an important parameter used in sedimentary basin models and geotechnical design to model fluid flow, locate hydrocarbon reserves and estimate ...

Adams, Amy Lynn

2014-01-01T23:59:59.000Z

458

Variable frequency microwave heating apparatus  

DOE Patents [OSTI]

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

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

1999-01-01T23:59:59.000Z

459

Massive Variability Surveys from Venezuela  

E-Print Network [OSTI]

At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ~180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community.

Cesar Briceno

2003-04-03T23:59:59.000Z

460

Method of controlling coherent synchroton radiation-driven degradation of beam quality during bunch length compression  

DOE Patents [OSTI]

A method of avoiding CSR induced beam quality defects in free electron laser operation by a) controlling the rate of compression and b) using a novel means of integrating the compression with the remainder of the transport system: both are accomplished by means of dispersion modulation. A large dispersion is created in the penultimate dipole magnet of the compression region leading to rapid compression; this large dispersion is demagnified and dispersion suppression performed in a final small dipole. As a result, the bunch is short for only a small angular extent of the transport, and the resulting CSR excitation is small.

Douglas, David R. (Newport News, VA); Tennant, Christopher D. (Williamsburg, VA)

2012-07-10T23:59:59.000Z

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


461

E-Print Network 3.0 - adiabatic compression plasma Sample Search...  

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

and can depend on the compression history... . The transformation of thermal energy into wave energy increases the ... Source: Fisch, Nathaniel J.- Princeton Plasma Physics...

462

E-Print Network 3.0 - axially compressed cylinders Sample Search...  

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

securely using a chain, belt, or strap - Must... distances Safety: Gas Cylinders Massachusetts Institute of Technology EHS Compressed Gases SOP (21607) 12... not withstand...

463

Spectral compression algorithms for the analysis of very large multivariate images  

DOE Patents [OSTI]

A method for spectrally compressing data sets enables the efficient analysis of very large multivariate images. The spectral compression algorithm uses a factored representation of the data that can be obtained from Principal Components Analysis or other factorization technique. Furthermore, a block algorithm can be used for performing common operations more efficiently. An image analysis can be performed on the factored representation of the data, using only the most significant factors. The spectral compression algorithm can be combined with a spatial compression algorithm to provide further computational efficiencies.

Keenan, Michael R. (Albuquerque, NM)

2007-10-16T23:59:59.000Z

464

Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange  

DOE Patents [OSTI]

In various embodiments, efficiency of energy storage and recovery systems compressing and expanding gas is improved via heat exchange between the gas and a heat-transfer fluid.

McBride, Troy O; Bell, Alexander; Bollinger, Benjamin R; Shang, Andrew; Chmiel, David; Richter, Horst; Magari, Patrick; Cameron, Benjamin

2013-07-02T23:59:59.000Z

465

Evaluation of ANSI compression in a bulk data file transfer system.  

E-Print Network [OSTI]

??This report evaluates the use of a newly proposed American National Standard Institute (ANSI) standard for data compression in a bulk data transmission system. An… (more)

Chaulklin, Douglas Gary

2010-01-01T23:59:59.000Z

466

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

E-Print Network [OSTI]

compression; plasma; neutralization; diagnostics; inductioncolumn with plasma plug, and beam diagnostics. Figure 2(a)the plasma column. 3. Experiment setup and diagnostics The

2006-01-01T23:59:59.000Z

467

Effect of ambient conditions and fuel properties on homogeneous charge compression ignition engine operation  

E-Print Network [OSTI]

Practical application of Homogeneous Charge Compression Ignition (HCCI) combustion must demonstrate robust responses to variations in environmental conditions. This work examines the impact of ambient conditions and fuel ...

Andreae, Morgan M. (Morgan MacKenzie)

2006-01-01T23:59:59.000Z

468

E-Print Network 3.0 - aluminum-alloy flat compression Sample...  

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

tension compression tension (a) Longitudinal (b) Short transverse... DUCTILE FRACTURE CHARACTERIZATION OF ALUMINUM ALLOY 2024-T351 USING DAMAGE PLASTICITY THEORY LIANG...

469

Numerical Modeling of Failure in Magnesium Alloys under Axial Compression and Bending for Crashworthiness Applications.  

E-Print Network [OSTI]

??Numerical modeling of failure was performed for magnesium alloys with circular and square cross-sections under axial compression. The failure criterion was employed using material model… (more)

Ali, Usman

2012-01-01T23:59:59.000Z

470

Mechanical and electronic-structure properties of compressed CdSe tetrapod nanocrystals  

E-Print Network [OSTI]

Mechanical and electronic-structure properties of compressed94720 USA The coupling of mechanical and optical propertiestheoretical examination of the mechanical properties of CdSe

Schrier, Joshua; Lee, Byounghak; Wang, Lin-Wang

2008-01-01T23:59:59.000Z

471

Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange  

DOE Patents [OSTI]

In various embodiments, efficiency of energy storage and recovery systems compressing and expanding gas is improved via heat exchange between the gas and a heat-transfer fluid.

McBride, Troy O.; Bell, Alexander; Bollinger, Benjamin R.

2012-08-07T23:59:59.000Z

472

E-Print Network 3.0 - adaptive pulse compression Sample Search...  

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

de mathmatiques Collection: Mathematics 10 Generation of 20-GHz picosecond pulse trains in the normal and anomalous dispersion Summary: compression in an anomalous dispersive...

473

E-Print Network 3.0 - artery compression syndrome Sample Search...  

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

results for: artery compression syndrome Page: << < 1 2 3 4 5 > >> 1 Journal of Biomedical Optics 16(2), 021110 (February 2011) Stent-induced coronary artery stenosis...

474

Cyclic Variability During the Transition Between Spark-ignited Combustion and HCCI  

SciTech Connect (OSTI)

Experimental observations of cyclic variability are described for the transition between conventional spark-ignited (SI) propagating-flame combustion and homogeneous charge compression ignition (HCCI) combustion in a single-cylinder, stoichiometrically fueled, gasoline engine. The engine under study is equipped with a fully variable valve actuation (VVA) system which was used to control the levels of internal exhaust gas recirculation (EGR) to achieve the transition from conventional SI to HCCI. Engine operation in both SI and HCCI modes was observed to be very stable with only minor, stochastic cyclic variability. However, during transitions between these modes, operation was observed to be highly unstable with high levels of cyclic variability and occasionally the engine could not sustain combustion. Analysis of the observed cyclic variability suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. The deterministic nature of the instabilities observed during the transition suggest that it is possible to make accurate, short-term predictions of combustion performance allowing for the possibility of developing on-line diagnostics and proactive control algorithms for expanding stable HCCI operation and improving transitions between conventional combustion modes and HCCI.

Edwards, Kevin Dean [ORNL; Daw, C Stuart [ORNL; Wagner, Robert M [ORNL; Green Jr, Johney Boyd [ORNL

2006-01-01T23:59:59.000Z

475

Review of Probability Random Variable  

E-Print Network [OSTI]

at close 4) Height of wheel going over a rocky road #12;3 Random Variable Non-examples 1) `Heads' or `Tails' on coin 2) Red or Black ball from urn But we can make these into RV's Basic Idea ­ don't know · Temperature · Wheel height #12;5 Given Continuous RV X... What is the probability that X = x0 ? Oddity : P

Fowler, Mark

476

Generation of Coherent X-Ray Radiation Through Modulation Compression  

E-Print Network [OSTI]

In this letter, we propose a scheme to generate tunable coherent X-ray radiation for future light source applications. This scheme uses an energy chirped electron beam, a laser modulators, a laser chirper and two bunch compressors to generate a prebunched kilo-Ampere current electron beam from a few tens Ampere electron beam out of a linac. The initial modulation energy wavelength can be compressed by a factor of $1+h_b R_{56}^a$ in phase space, where $h_b$ is the energy bunch length chirp introduced by the laser chirper, $R_{56}^a$ is the momentum compaction factor of the first bunch compressor. As an illustration, we present an example to generate more than $400$ MW, $170$ atto-seconds pulse, $1$ nm coherent X-ray radiation using a $60$ Ampere electron beam out of the linac and $200$ nm laser seed. Both the final wavelength and the radiation pulse length in the proposed scheme are tunable by adjusting the compression factor and the laser parameters.

Qiang, Ji

2010-01-01T23:59:59.000Z

477

Generation of Coherent X-Ray Radiation Through Modulation Compression  

SciTech Connect (OSTI)

In this letter, we propose a scheme to generate tunable coherent X-ray radiation for future light source applications. This scheme uses an energy chirped electron beam, a laser modulators, a laser chirper and two bunch compressors to generate a prebunched kilo-Ampere current electron beam from a few tens Ampere electron beam out of a linac. The initial modulation energy wavelength can be compressed by a factor of 1 + h{sub b}R{sub 56}{sup a} phase space, where h{sub b} is the energy bunch length chirp introduced by the laser chirper, R{sub 56}{sup a} is the momentum compaction factor of the first bunch compressor. As an illustration, we present an example to generate more than 400 MW, 170 atto-seconds pulse, 1 nm coherent X-ray radiation using a 60 Ampere electron beam out. of the linac and 200 nm laser seed. Both the final wavelength and the radiation pulse length in the proposed scheme are tunable by adjusting the compression factor and the laser parameters.

Qiang, Ji; Wu, Juhao

2010-12-14T23:59:59.000Z

478

Optical transitions of holes in uniaxially compressed germanium  

SciTech Connect (OSTI)

Spontaneous emission and photoconductivity of germanium with gallium impurity are studied for determining the energy spectrum of hole states in this material in which radiation can be induced as a result of transitions of holes between these states. Holes were excited by electric field pulses with a strength up to 12 kV/cm at T = 4.2 K under uniaxial compression of samples up to 12 kbar. It has been found that hole emission spectra for transitions between resonant and local states of the impurity have a structure identical to the photoconductivity and absorption spectra. Transitions from resonance states, which are associated with the heavy hole subband, have not been detected. It has been found that in an electric field lower than 100 V/cm, a compressed crystal emits as a result of transitions of heavy holes. In a strong electric field (1-3 kV/cm), emission is observed in the energy range up to 140 meV, and transitions with emission of TA and LO phonons appear in such a field. The emission spectra under pressures of 0 and 12 kbar differ insignificantly. Hence, it follows that the contributions from heavy and light holes in a strong electric field are indistinguishable.

Pokrovskii, Ya. E., E-mail: yaep@cplire.ru; Khvalkovskii, N. A. [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Russian Federation)] [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Russian Federation)

2013-10-15T23:59:59.000Z

479

Massive-scale RDF Processing Using Compressed Bitmap Indexes  

SciTech Connect (OSTI)

The Resource Description Framework (RDF) is a popular data model for representing linked data sets arising from the web, as well as large scienti#12;c data repositories such as UniProt. RDF data intrinsically represents a labeled and directed multi-graph. SPARQL is a query language for RDF that expresses subgraph pattern-#12;nding queries on this implicit multigraph in a SQL- like syntax. SPARQL queries generate complex intermediate join queries; to compute these joins e#14;ciently, we propose a new strategy based on bitmap indexes. We store the RDF data in column-oriented structures as compressed bitmaps along with two dictionaries. This paper makes three new contributions. (i) We present an e#14;cient parallel strategy for parsing the raw RDF data, building dictionaries of unique entities, and creating compressed bitmap indexes of the data. (ii) We utilize the constructed bitmap indexes to e#14;ciently answer SPARQL queries, simplifying the join evaluations. (iii) To quantify the performance impact of using bitmap indexes, we compare our approach to the state-of-the-art triple-store RDF-3X. We #12;nd that our bitmap index-based approach to answering queries is up to an order of magnitude faster for a variety of SPARQL queries, on gigascale RDF data sets.

Madduri, Kamesh; Wu, Kesheng

2011-05-26T23:59:59.000Z

480

In situ repair of a failed compression fitting  

DOE Patents [OSTI]

A method and apparatus for the in situ repair of a failed compression fitting is provided. Initially, a portion of a guide tube is inserted coaxially in the bore of the compression fitting and locked therein. A close fit dethreading device is then coaxially mounted on the guide tube to cut the threads from the fitting. Thereafter, the dethreading device and guide tube are removed and a new fitting is inserted onto the dethreaded fitting with the body of the new fitting overlaying the dethreaded portion. Finally, the main body of the new fitting is welded to the main body of the old fitting whereby a new threaded portion of the replacement fitting is precisely coaxial with the old threaded portion. If needed, a bushing is located on the dethreaded portion which is sized to fit snugly between the dethreaded portion and the new fitting. Preferably, the dethreading device includes a cutting tool which is moved incrementally in a radial direction whereby the threads are cut from the threaded portion of the failed fitting in increments.

Wolbert, R.R.; Jandrasits, W.G.

1985-08-05T23:59:59.000Z

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


481

In situ repair of a failed compression fitting  

DOE Patents [OSTI]

A method and apparatus for the in situ repair of a failed compression fitg is provided. Initially, a portion of a guide tube is inserted coaxially in the bore of the compression fitting and locked therein. A close fit dethreading device is then coaxially mounted on the guide tube to cut the threads from the fitting. Thereafter, the dethreading device and guide tube are removed and a new fitting is inserted onto the dethreaded fitting with the body of the new fitting overlaying the dethreaded portion. Finally, the main body of the new fitting is welded to the main body of the old fitting whereby a new threaded portion of the replacement fitting is precisely coaxial with the old threaded portion. If needed, a bushing is located on the dethreaded portion which is sized to fit snugly between the dethreaded portion and the new fitting. Preferably, the dethreading device includes a cutting tool which is moved incrementally in a radial direction whereby the threads are cut from the threaded portion of the failed fitting in increments.

Wolbert, Ronald R. (McKees Rocks, PA); Jandrasits, Walter G. (Pittsburgh, PA)

1986-01-01T23:59:59.000Z

482

Rapid Replication of High Aspect Ratio Molds for UV Embossing  

E-Print Network [OSTI]

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

Yan, Yehai

483

The Ne/O abundance ratio in the quiet Sun  

E-Print Network [OSTI]

Aims: To determine the neon-to-oxygen abundance in the quiet Sun, a proxy for the photospheric abundance ratio. Method: An emission measure method applied to extreme ultraviolet emission lines of Ne IV-VI and O III-V ions observed by the Coronal Diagnostic Spectrometer on the SOHO satellite. Results: The average Ne/O abundance ratio in supergranule cell centre regions is 0.18 +/- 0.05, while in supergranule network regions is 0.16 +/- 0.04. A photospheric Ne/O ratio of 0.17 +/- 0.05 is suggested, in good agreement with the most recent compilation of solar photospheric abundances, but discrepant with a recent Ne/O ratio derived from stellar X-ray spectra and revised neon abundances suggested from solar interior models.

P. R. Young

2005-10-10T23:59:59.000Z

484

Chloride-Magnesium Ratio of Shallow Groundwaters as a Regional...  

Open Energy Info (EERE)

Chloride-Magnesium Ratio of Shallow Groundwaters as a Regional Geothermal Indicator in Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

485

aspect ratio silicon: Topics by E-print Network  

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

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

486

Separated Response Function Ratios in Exclusive, Forward ?[superscript ±] Electroproduction  

E-Print Network [OSTI]

The study of exclusive ?[superscript ±] electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio R[subscript L] = ?[?? over L]/?[?+ over ...

Huber, G.?M.

487

Interpretation of the atmospheric muon charge ratio in MINOS  

E-Print Network [OSTI]

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

Philip Schreiner; Maury Goodman

2007-06-04T23:59:59.000Z

488

The E2/M1 ratio in {Delta} photoproduction  

SciTech Connect (OSTI)

New high-precision measurements of p({rvec {gamma}}, {pi}) and p({rvec {gamma}}, {gamma}) cross sections and beam asymmetries have been combined with other polarization ratios in a simultaneous analysis of both reactions. The E2/M1 mixing ratio for the n {r_arrow} {Delta} transition extracted from this analysis is EMR = {minus}3.0% {+-} 0.3 (stat+sys) {+-} 0.2 (model).

Hoblit, S. [Brookhaven National Lab., Upton, NY (United States). Physics Dept.]|[Univ. of Virginia, Charlottesville, VA (United States). Dept. of Physics; Blanpied, G. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Physics; Blecher, M. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Physics Dept.] [and others; LEGS Collaboration

1997-10-01T23:59:59.000Z

489

System and method for high precision isotope ratio destructive analysis  

DOE Patents [OSTI]

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

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

2013-07-02T23:59:59.000Z

490

Variable flexure-based fluid filter  

DOE Patents [OSTI]

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

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

2007-03-13T23:59:59.000Z

491

Effect of cooler electrons on a compressive ion acoustic solitary wave in a warm ion plasma — Forbidden regions, double layers, and supersolitons  

SciTech Connect (OSTI)

It is observed that the presence of a minority component of cooler electrons in a three component plasma plays a deterministic role in the evolution of solitary waves, double layers, or the newly discovered structures called supersolitons. The inclusion of the cooler component of electrons in a single electron plasma produces sharp increase in nonlinearity in spite of a decrease in the overall energy of the system. The effect maximizes at certain critical value of the number density of the cooler component (typically 15%–20%) giving rise to a hump in the amplitude variation profile. For larger amplitudes, the hump leads to a forbidden region in the ambient cooler electron concentration which dissociates the overall existence domain of solitary wave solutions in two distinct parameter regime. It is observed that an inclusion of the cooler component of electrons as low as < 1% affects the plasma system significantly resulting in compressive double layers. The solution is further affected by the cold to hot electron temperature ratio. In an adequately hotter bulk plasma (i.e., moderately low cold to hot electron temperature ratio), the parameter domain of compressive double layers is bounded by a sharp discontinuity in the corresponding amplitude variation profile which may lead to supersolitons.

Ghosh, S. S., E-mail: sukti@iigs.iigm.res.in [Indian Institute of Geomagnetism, New Panvel, Navi Mumbai 410218 (India); Sekar Iyengar, A. N. [Plasma Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India)

2014-08-15T23:59:59.000Z

492

Principal Components Instrumental Variable Estimation  

E-Print Network [OSTI]

of the main results are displayed in two appendices. 2 Econometric Framework Consider the simultaneous equations model y = X? + u and X = Z?+ V , (1) 1 An advantage of such general structure is that the ‘large-sample’ condition used in previous studies Kn/ p n... ? 0, where Kn is the number of instruments and n is the sample size, is not required in our asymptotic approximations. 4 where y is the n × 1 vector containing n observations of the dependent variable; X is the n × G matrix with observations...

Winkelried, Diego; Smith, Richard J.

2011-01-31T23:59:59.000Z

493

Variable Average Absolute Percent Differences  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500II FieldVacancy-InducedCloudPoissonVampire Power1 -Variable

494

Variable Mass Theories of Gravity  

E-Print Network [OSTI]

Several attempts to construct theories of gravity with variable mass are considered. The theoretical impacts of allowing the rest mass to vary with respect to time or an appropriate curve parameter are examined in the framework of Newtonian and Einsteinian gravity theories. In further steps, scalar-tensor theories are examined with respect to their relation to the variation of the mass and in an ultimate step, an additional coordinate is introduced and its possible relation to the mass is examined, yielding a five dimensional space-time-matter theory.

M. Leclerc

2002-12-03T23:59:59.000Z

495

On the Performance of Lossy Compression Schemes for Energy Constrained Sensor Networking  

E-Print Network [OSTI]

A On the Performance of Lossy Compression Schemes for Energy Constrained Sensor Networking DAVIDE of Padova Lossy temporal compression is key for energy constrained wireless sensor networks (WSN), where complexity and energy consumption. Specifically, we first carry out a performance evaluation of existing

Rossi, Michele

496

SPATIAL-TEMPORAL TECHNIQUES FOR PREDICTION AND COMPRESSION OF SOIL FERTILITY DATA  

E-Print Network [OSTI]

SPATIAL-TEMPORAL TECHNIQUES FOR PREDICTION AND COMPRESSION OF SOIL FERTILITY DATA D. Pokrajac propose several techniques for data reduction and spatial- temporal prediction in precision agriculture and applied for analysis and compression of multi-temporal precision agriculture data. The spatial

Obradovic, Zoran

497

Compressible air cushioning in liquid-solid impacts Peter D. Hicks  

E-Print Network [OSTI]

Compressible air cushioning in liquid-solid impacts Peter D. Hicks Department of Mechanical of Mathematics, University of East Anglia, Norwich, NR4 7TJ, UK. r.purvis@uea.ac.uk Abstract--Air cushioning the influence of air compressibility. Building on earlier incompress- ible analyses, a local asymptotic model

Purvis, Richard

498

Simultaneous compression and characterization of ultrashort laser pulses using chirped mirrors and glass wedges  

E-Print Network [OSTI]

We present a simple and robust technique to retrieve the phase of ultrashort laser pulses, based on a chirped mirror and glass wedges compressor. It uses the compression system itself as a diagnostic tool, thereby making unnecessary the use of complementary diagnostic tools. We used this technique to compress and characterize 7.1 fs laser pulses from an ultrafast laser oscillator.

Miranda, Miguel; Arnold, Cord; L'Huillier, Anne; Crespo, Helder

2011-01-01T23:59:59.000Z

499

Improving MPEG-4 coding performance by jointly optimising compression and blocking effect elimination  

E-Print Network [OSTI]

1 Improving MPEG-4 coding performance by jointly optimising compression and blocking effect and Information Engineering The Hong Kong Polytechnic University, Hong Kong ABSTRACT In most current block into account in the compression and the two processes can be jointly optimised. An example is also provided

Chan, Chris Y. H.

500

Numerical study of compressibility effects on the reversed shear Alfvén eigenmode in tokamak plasma  

SciTech Connect (OSTI)

Compressibility effects on the reversed shear Alfvén eigenmode in tokamak plasma are studied numerically. It is shown that compressibility is favorable for the existence of the reversed shear Alfvén eigenmode even without the pressure gradient, and the frequency of the reversed shear Alfvén eigenmode is modified by the geodesic frequency, which is consistent with an analytical theory.

Yu, Limin; Zhang, Xianmei [Department of Physics, East China University of Science and Technology, Shanghai 200237 (China)] [Department of Physics, East China University of Science and Technology, Shanghai 200237 (China); Sheng, Zheng-Mao [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)] [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)

2013-08-15T23:59:59.000Z