Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Energy, Office of Inspector General - Recovery Act Strategy Overview Under the recently passed American Recovery and Reinvestment Act of 2009, the Department of Energy will receive approximately $40 billion for various energy initiatives. The Recovery Act will have a significant impact on the operations and activities of the Department and, in turn, the Office of Inspector General. In recognition of the need for effective oversight to protect taxpayer interests, the Recovery Act includes the
Yanbu, Saudi Arabia: Energy Resources | Open Energy Information
Saudi Arabia. Registered Energy Companies in Yanbu, Saudi Arabia Saudi Aramco Mobile Refinery Company (SAMREF) References "NGA Geonames Search" Retrieved from "http:...
Riyadh, Saudi Arabia: Energy Resources | Open Energy Information
Riyadh is a city in Saudi Arabia. Registered Energy Companies in Riyadh, Saudi Arabia King Abdulaziz City for Science and Technology Saudi Electricity Company References "NGA...
Readout of Energy Secretary Chu's Meetings in Riyadh, Saudi Arabia...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Energy Secretary Chu's Meetings in Riyadh, Saudi Arabia Readout of Energy Secretary Chu's Meetings in Riyadh, Saudi Arabia February 22, 2010 - 12:00am Addthis Secretary Chu was in ...
6th Carbon Sequestration Leadership Forum Ministers’ Meeting Underway in Saudi Arabia
Broader source: Energy.gov [DOE]
The event, which is being co-chaired by the United States and Saudi Arabia, kicked off with various policy and technical meetings with representatives from more than 20 countries. It will culminate on Wednesday with a day-long conference of energy ministers, including Energy Secretary Ernest Moniz.
U.S., Saudi Arabia Announce International Collaboration on Supercritical
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
CO2 Tech Development | Department of Energy , Saudi Arabia Announce International Collaboration on Supercritical CO2 Tech Development U.S., Saudi Arabia Announce International Collaboration on Supercritical CO2 Tech Development June 3, 2016 - 1:00pm Addthis The U. S. and the Kingdom of Saudi Arabia have announced the intention to establish an international consortium to promote the research, development, and demonstration (RD&D) of supercritical carbon dioxide (sCO2) power cycles. The
Secretary Bodman Travels to Saudi Arabia to Discuss Global Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Investments | Department of Energy Saudi Arabia to Discuss Global Energy Investments Secretary Bodman Travels to Saudi Arabia to Discuss Global Energy Investments January 19, 2007 - 10:38am Addthis Furthers Strategic Energy Dialogue between the Nations and Highlights U.S. - Saudi Scientific Innovation RIYADH, SAUDI ARABIA - U.S. Secretary of Energy Samuel W. Bodman today continued his six-nation visit to the Middle East and Europe with a two-day stop in Saudi Arabia where he met with Saudi
GE Opens Research Center in Saudi Arabia | GE Global Research
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
GE's US1 billion investment in Saudi Arabia creates a path for new initiatives in localization, technology innovation and manufacturing to drive country's digital transformation...
NASA Remote Sensing Validation Data: Saudi Arabia
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Myers, Daryl R. [NREL; Al-Abbadi, Naif [King Abdulaziz City for Science and Technology, Energy Research Institite; Wilcox, Steve [NREL
Since 1995, the King Abdulaziz City for Science and Technology (KACST) and the National Renewable Energy Laboratory (NREL) have co-operated to establish a 12 station network of high quality solar radiation monitoring installations across the Kingdom of Saudi Arabia. NREL and KACST realized the value of accurate surface solar radiation flux measurements for validation of satellite derived surface and atmospheric solar radiation flux measurements, and is making this data available to support validation of satellite data products related to the NASA Mission to Planet Earth component of the Earth Science Enterprise Earth Observing System (EOS) project to evaluate long term climate trends based on measuements from EOS Terra Platforms. A CIMEL 8 channel sunphotometer for measuring aerosol optical depth at 6 wavelengths and total column water has been deployed at the Solar Village station since February 24, 1999. [Taken from http://rredc.nrel.gov/solar/new_data/Saudi_Arabia/
Waters and desalination programs of Saudi Arabia
Wojcik, C.K.; Maadhah, A.G.
1981-07-01
Saudi Arabia is an arid desert country without rivers or sweet-water lakes. It does, however, have large amounts of ground water and seawater. These waters must be desalted by some means in order to make them potable. The most frequently used methods for that purpose are: multistage flash (MSF) evaporation, reverse osmosis (RO), and electrodialysis (ED). Because of rapid industrialization of the country, the demand for fresh water has been growing steadily. This, in turn, has resulted in a spectacular growth of the water-desalination industry. This paper discusses the availability and properties of the waters. It gives a detailed description of the major accomplishments and of the ongoing and future programs in the field of water desalination in Saudi Arabia. 14 references, 6 figures, 8 tables.
A Top to Bottom Lithospheric Study of Africa and Arabia
Pasyanos, M
2006-10-31
We study the lithospheric structure of Africa, Arabia and adjacent oceanic regions with fundamental-mode surface waves over a wide period range. Including short period group velocities allows us to examine shallower features than previous studies of the whole continent. In the process, we have developed a crustal thickness map of Africa. Main features include crustal thickness increases under the West African, Congo, and Kalahari cratons. We find crustal thinning under Mesozoic and Cenozoic rifts, including the Benue Trough, Red Sea, and East, Central, and West African rift systems. Crustal shear wave velocities are generally faster in oceanic regions and cratons, and slower in more recent crust and in active and formerly active orogenic regions. Deeper structure, related to the thickness of cratons and modern rifting, is generally consistent with previous work. Under cratons we find thick lithosphere and fast upper mantle velocities, while under rifts we find thinned lithosphere and slower upper mantle velocities. There are no consistent effects in areas classified as hotspots, indicating that there seem to be numerous origins for these features. Finally, it appears that the African Superswell has had a significantly different impact in the north and the south, indicating specifics of the feature (temperature, time of influence, etc.) to be dissimilar between the two regions. Factoring in other information, it is likely that the southern portion has been active in the past, but that shallow activity is currently limited to the northern portion of the superswell.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
PACKAGE INCLUDES: Airfare from Seattle, 4 & 5 Star Hotels, Transfers, Select Meals, Guided Tours and Excursions DAY 01: BANGKOK - ARRIVAL DAY 02: BANGKOK - SIGHTSEEING DAY 03: BANGKOK - FLOATING MARKET DAY 04: BANGKOK - AT LEISURE DAY 05: BANGKOK - CHIANG MAI BY AIR DAY 06: CHIANG MAI - SIGHTSEEING DAY 07: CHIANG MAI - ELEPHANT CAMP DAY 08: CHIANG MAI - PHUKET BY AIR DAY 09: PHUKET - PHI PHI ISLAND BY FERRY DAY 10: PHUKET - AT LEISURE DAY 11: PHUKET - CORAL ISLAND BY SPEEDBOAT DAY 12: PHUKET
Microsoft PowerPoint - Saudi Arabia 2-22-10 final for distribution.pptx |
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Department of Energy Saudi Arabia 2-22-10 final for distribution.pptx Microsoft PowerPoint - Saudi Arabia 2-22-10 final for distribution.pptx Microsoft PowerPoint - Saudi Arabia 2-22-10 final for distribution.pptx (3.54 MB) More Documents & Publications Microsoft PowerPoint - UAE Masdar 2-24
GE Opens Research Center in Saudi Arabia | GE Global Research
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
GE's US$1 billion investment in Saudi Arabia creates a path for new initiatives in localization, technology innovation and manufacturing to drive country's digital transformation by 2020 Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) GE's US$1 billion investment in Saudi Arabia creates a path for new initiatives in
Broader source: Energy.gov [DOE]
JEDDAH, SAUDI ARABIA - At the conclusion of the Jeddah Energy Meeting in Saudi Arabia, U.S. Secretary of Energy Samuel W. Bodman issued the following statement:
Meeting Our Partners in Saudi Arabia and U.S. Military Forces in Bahrain |
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Department of Energy Our Partners in Saudi Arabia and U.S. Military Forces in Bahrain Meeting Our Partners in Saudi Arabia and U.S. Military Forces in Bahrain January 26, 2015 - 1:15am Addthis Deputy Secretary of Energy Elizabeth Sherwood-Randall looks out at Dhahran, Saudi Arabia, from a helicopter en route to view the Manifa Oil Field. | Photo by Kathryn Grant, Energy Department. Deputy Secretary of Energy Elizabeth Sherwood-Randall looks out at Dhahran, Saudi Arabia, from a helicopter en
Chalasani, P.; Saias, I.; Jha, S.
1996-04-08
As increasingly large volumes of sophisticated options (called derivative securities) are traded in world financial markets, determining a fair price for these options has become an important and difficult computational problem. Many valuation codes use the binomial pricing model, in which the stock price is driven by a random walk. In this model, the value of an n-period option on a stock is the expected time-discounted value of the future cash flow on an n-period stock price path. Path-dependent options are particularly difficult to value since the future cash flow depends on the entire stock price path rather than on just the final stock price. Currently such options are approximately priced by Monte carlo methods with error bounds that hold only with high probability and which are reduced by increasing the number of simulation runs. In this paper the authors show that pricing an arbitrary path-dependent option is {number_sign}-P hard. They show that certain types f path-dependent options can be valued exactly in polynomial time. Asian options are path-dependent options that are particularly hard to price, and for these they design deterministic polynomial-time approximate algorithms. They show that the value of a perpetual American put option (which can be computed in constant time) is in many cases a good approximation to the value of an otherwise identical n-period American put option. In contrast to Monte Carlo methods, the algorithms have guaranteed error bounds that are polynormally small (and in some cases exponentially small) in the maturity n. For the error analysis they derive large-deviation results for random walks that may be of independent interest.
Approximate error conjugation gradient minimization methods
Kallman, Jeffrey S
2013-05-21
In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.
Microsoft PowerPoint - Saudi Arabia 2-22-10 final for distribution.pptx
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Solving the Energy and Climate Challenge Together Secretary Steven Chu International Energy Forum Riyadh, Saudi Arabia 22 February 2010 King Faisal Prize Winners, 1993 The United States of America and Saudi Arabia have a long and deep relationship We are adding a new dimension to our Saudi King Abdul Aziz Al Saud and President Franklin Delano Roosevelt on the USS Quincy 65 years ago dimension to our relationship - as we move to meet shared energy and climate challenges (1) The global economy
Approximate circuits for increased reliability
Hamlet, Jason R.; Mayo, Jackson R.
2015-08-18
Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.
Approximate circuits for increased reliability
Hamlet, Jason R.; Mayo, Jackson R.
2015-12-22
Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.
The status and prospective of environmental radiation monitoring stations in Saudi Arabia
Al-Kheliewi, Abdullah S.; Holzheimer, Clous
2014-09-30
The use of nuclear technology requires an environmental monitoring program to ensure the safety of the environment, and to protect people from the hazards of radioactive materials, and nuclear accidents. Nuclear accidents are unique, for they incur effects that surpass international frontiers, and can even have a long lasting impact on Earth. Such was the case of the Chernobyl accident in the Ukraine on April 6, 1986. For that purpose, international and national efforts come together to observe for any nuclear or radioactive accident. Many states, including Saudi Arabia which oversees the operation of the National Radiation, Environmental and Early Monitoring Stations, The Radiation Monitoring Stations(RMS’s) are currently scattered across 35 cities in the country,. These locations are evaluated based on various technological criteria such as border cities, cities of high population density, wind direction, etc. For new nuclear power plants hovering around, it is strongly recommended to increase the number of radiation monitoring stations to warn against any threat that may arise from a nuclear leak or accident and to improve the performance of the existing RMS’s. SARA (Spectroscopic Monitoring Station for air) should be implemented due to the high sensitivity to artificial radiation, automatic isotope identification, free of maintenance, and fully independent due to solar power supply (incl. battery backup) and wireless communication (GPRS)
Evolution of gas processing industry in Saudi Arabia
Showail, A.
1983-01-01
The beginning of the natural gas processing industry in Saudi Arabia is traced back to 1959 when Aramco embarked on a program to recover natural gas liquids (NGL) for export from low pressure gases such as stabilizer overhead, spheroid, tank farm, and refinery off-gases. The processing scheme involves compression and refrigeration to extract C3+ raw NGL, a raw NGL gathering system, and a fractionation plant to separate propane, butane, and natural gasoline. NGL extracted in Abqaiq and Ras Tanura is moved to Ras Tanura for fractionation, storage, and export. The system, built in several increments, has total design capacity of 500 MMscfd of feed gases to produce 320,000 bpd of NGL composed of 40% propane, 30% butane, and 30% natural gasoline. Phase II of the Saudi gas program envisages collection and processing of associated gas produced with Arabian medium and heavy crude oils largely in the northern onshore and offshore fields. Further domestic development may focus on more diversification in gas product utilization and on upgrading to higher value products.
Automated management of radioactive sources in Saudi Arabia
Al-Kheliewi, Abdullah S.; Jamil, M. F.; Basar, M. R.; Tuwaili, W. R.
2014-09-30
For usage of radioactive substances, any facility has to register and take license from relevant authority of the country in which such facility is operating. In the Kingdom of Saudi Arabia (KSA), the authority for managing radioactive sources and providing licenses to organizations for its usage is the National Center of Radiation Protection (NCRP). This paper describes the system that automates registration and licensing process of the National Center of Radiation Protection. To provide 24×7 accesses to all the customers of NCRP, system is developed as web-based application that provide facility to online register, request license, renew license, check request status, view historical data and reports etc. and other features are provided as Electronic Services that would be accessible to users via internet. The system also was designed to streamline and optimize internal operations of NCRP besides providing ease of access to its customers by implementing a defined workflow through which every registration and license request will be routed. In addition to manual payment option, the system would also be integrated with SADAD (online payment system) that will avoid lengthy and cumbersome procedures associated with manual payment mechanism. Using SADAD payment option license fee could be paid through internet/ATM machine or branch of any designated bank, Payment will be instantly notified to NCRP hence delay in funds transfer and verification of invoice could be avoided, SADAD integration is discussed later in the document.
Charge-conjugation symmetric complete impulse approximation for...
Office of Scientific and Technical Information (OSTI)
from the spectator quark (referred to as the relativistic impulse approximation). In this study we also include the contributions from the poles of the quark which interacts with ...
Pump apparatus including deconsolidator
Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew
2014-10-07
A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.
Optical modulator including grapene
Liu, Ming; Yin, Xiaobo; Zhang, Xiang
2016-06-07
The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.
Plasma Physics Approximations in Ares
Managan, R. A.
2015-01-08
Lee & More derived analytic forms for the transport properties of a plasma. Many hydro-codes use their formulae for electrical and thermal conductivity. The coefficients are complex functions of Fermi-Dirac integrals, F_{n}( μ/θ ), the chemical potential, μ or ζ = ln(1+e^{ μ/θ} ), and the temperature, θ = kT. Since these formulae are expensive to compute, rational function approximations were fit to them. Approximations are also used to find the chemical potential, either μ or ζ . The fits use ζ as the independent variable instead of μ/θ . New fits are provided for A^{α} (ζ ),A^{β} (ζ ), ζ, f(ζ ) = (1 + e^{-μ/θ})F_{1/2}(μ/θ), F_{1/2}'/F_{1/2}, F_{c}^{α}, and F_{c}^{β}. In each case the relative error of the fit is minimized since the functions can vary by many orders of magnitude. The new fits are designed to exactly preserve the limiting values in the non-degenerate and highly degenerate limits or as ζ→ 0 or ∞. The original fits due to Lee & More and George Zimmerman are presented for comparison.
Sale of US military aircraft to Saudi Arabia. Master`s thesis
Bents, E.R.
1995-05-01
The end of the Cold War in the late 1980s resulted in a gigantic downsizing and consolidation of America`s defense industries, as domestic demand plummeted and the volume of international arms trading fell. However, in total world arms exports the United States exports more arms than any other nation. The country of Saudi Arabia has been the destination of a disproportionate amount of these weapons. The following account is an examination of the US military aerospace industry, the world military aerospace market, US government policy concerning arms exports, and the Saudi aerospace market. Each of these entities profoundly impacts US-Saudi military aerospace commerce. By individually analyzing the above factors, it will be demonstrated that the supply relationship between the US and Saudi Arabia is dependent on the convergence of several long standing and deep seated aspirations on the part of the three major players: the US Aerospace Industry, the US Government, and the Saudi Government. The US military aerospace industry`s exports are critical to ensure its independent survival, help fund crucial RD programs, and maintain a viable defense high tech industrial base in the U.S. In addition, it wishes to exert a military presence in the Gulf area and nurture relations with Saudi Arabia in particular, as the world`s leading oil producer. The Saudi government requires a military defense anchored in high tech aerospace systems, as well as a dependable and capable military ally such as the US.
An approximation technique for jet impingement flow
Najafi, Mahmoud; Fincher, Donald; Rahni, Taeibi; Javadi, KH.; Massah, H.
2015-03-10
The analytical approximate solution of a non-linear jet impingement flow model will be demonstrated. We will show that this is an improvement over the series approximation obtained via the Adomian decomposition method, which is itself, a powerful method for analysing non-linear differential equations. The results of these approximations will be compared to the Runge-Kutta approximation in order to demonstrate their validity.
Kingdom of Saudi Arabia Ministry of Petroleum and Mineral Resources...
leaders and government ministers. The Supreme Council is responsible for petroleum and natural gas policy-making, including contract review. It also sets broad policies for the...
Selection of a suitable reactor type for water desalination and power generation in Saudi Arabia
Hussein, F.M.
1988-03-01
Selection of a reactor type suitable for water desalination and power generation is a complex process that involves the evaluation of many criteria and requires the professional judgment of many experts in different fields. A reactor type that is suitable for one country might not be suitable for another. This is especially true in the case of Saudi Arabia because of its strategic location, the nature of its land and people, and its moderate technological situation. A detailed study using a computer code based on Saaty's mathematical pairwise comparison technique and developed in a previous study was carried out to find the most suitable reactor for water desalination and power generation in Saudi Arabia from among five potential types: boiling water reactors (BWRs), pressurized water reactors, CANDU heavy water reactors (HWRs), steam-generating heavy water reactors (SGHWRs), and high-temperature gas-cooled reactors. It was concluded that the CANDU HWR is the most suitable type for this purpose followed first by the BWR, then the SGHWR.
A Survey of Techniques for Approximate Computing
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Mittal, Sparsh
2016-03-18
Approximate computing trades off computation quality with the effort expended and as rising performance demands confront with plateauing resource budgets, approximate computing has become, not merely attractive, but even imperative. Here, we present a survey of techniques for approximate computing (AC). We discuss strategies for finding approximable program portions and monitoring output quality, techniques for using AC in different processing units (e.g., CPU, GPU and FPGA), processor components, memory technologies etc., and programming frameworks for AC. Moreover, we classify these techniques based on several key characteristics to emphasize their similarities and differences. Finally, the aim of this paper is tomore » provide insights to researchers into working of AC techniques and inspire more efforts in this area to make AC the mainstream computing approach in future systems.« less
An improved proximity force approximation for electrostatics
Fosco, Cesar D.; Instituto Balseiro, Universidad Nacional de Cuyo, R8402AGP Bariloche ; Lombardo, Fernando C.; IFIBA ; Mazzitelli, Francisco D.
2012-08-15
A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated with their shapes. Indeed, in the so called 'proximity force approximation' the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contributions of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied in different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful for discussing the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes. - Highlights: Black-Right-Pointing-Pointer The proximity force approximation (PFA) has been widely used in different areas. Black-Right-Pointing-Pointer The PFA can be improved using a derivative expansion in the shape of the surfaces. Black-Right-Pointing-Pointer We use the improved PFA to compute electrostatic forces between conductors. Black-Right-Pointing-Pointer The results can be used as an analytic benchmark for numerical calculations in AFM. Black-Right-Pointing-Pointer Insight is provided for people who use the PFA to compute nuclear and Casimir forces.
Variational principles with Pad approximants for tearing mode analysis
Cole, Andrew J.; Finn, John M.
2014-03-15
Tearing modes occur in several distinct physical regimes, and it is often important to compute the inner layer response for these modes with various effects. There is a need for an approximate and efficient method of solving the inner layer equations in all these regimes. In this paper, we introduce a method of solving the inner layer equations based on using a variational principle with Pad approximants. For all the regimes considered, the main layer equations to be solved are inhomogeneous, and Pad approximants give a convenient and efficient method of satisfying the correct asymptotic behavior at the edge of the layer. Results using this variational principlePad approximant method in three of these regimes is presented. These regimes are the constant-? resistive-inertial (RI) regime, the constant-? viscoresistive regime, and the non-constant-? inviscid tearing regime. The last regime includes the constant-? RI regime and the inertial regime. The results show that reasonable accuracy can be obtained very efficiently with Pad approximants having a small number of parameters.
Extractant composition including crown ether and calixarene extractants
Meikrantz, David H.; Todd, Terry A.; Riddle, Catherine L.; Law, Jack D.; Peterman, Dean R.; Mincher, Bruce J.; McGrath, Christopher A.; Baker, John D.
2009-04-28
An extractant composition comprising a mixed extractant solvent consisting of calix[4] arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The DtBu18C6 may be present at from approximately 0.01M to approximately 0.4M, such as at from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present at from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The extractant composition further comprises an aqueous phase. The mixed extractant solvent may be used to remove cesium and strontium from the aqueous phase.
MHK technology developments include current
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
technology developments include current energy conversion (CEC) devices, for example, hydrokinetic turbines that extract power from water currents (riverine, tidal, and ocean) and wave energy conversion (WEC) devices that extract power from wave motion. Sandia's MHK research leverages decades of experience in engineering, design, and analysis of wind power technologies, and its vast research complex, including high- performance computing (HPC), advanced materials and coatings, nondestructive
Second derivatives for approximate spin projection methods
Thompson, Lee M.; Hratchian, Hrant P.
2015-02-07
The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical second derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives.
Relativistic Random Phase Approximation At Finite Temperature
Niu, Y. F.; Paar, N.; Vretenar, D.; Meng, J.
2009-08-26
The fully self-consistent finite temperature relativistic random phase approximation (FTRRPA) has been established in the single-nucleon basis of the temperature dependent Dirac-Hartree model (FTDH) based on effective Lagrangian with density dependent meson-nucleon couplings. Illustrative calculations in the FTRRPA framework show the evolution of multipole responses of {sup 132}Sn with temperature. With increased temperature, in both monopole and dipole strength distributions additional transitions appear in the low energy region due to the new opened particle-particle and hole-hole transition channels.
COMPLEXITY & APPROXIMABILITY OF QUANTIFIED & STOCHASTIC CONSTRAINT SATISFACTION PROBLEMS
H. B. HUNT; M. V. MARATHE; R. E. STEARNS
2001-06-01
Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S and T be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SATc(S).) Here, we study simultaneously the complexity of decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. We present simple yet general techniques to characterize simultaneously, the complexity or efficient approximability of a number of versions/variants of the problems SAT(S), Q-SAT(S), S-SAT(S),MAX-Q-SAT(S) etc., for many different such D,C,S,T. These versions/variants include decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. Our unified approach is based on the following two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic representability. Some of the results extend the earlier results in [Pa85,LMP99,CF+93,CF+94] Our techniques and results reported here also provide significant steps towards obtaining dichotomy theorems, for a number of the problems above, including the problems MAX-Q-SAT(S), and MAX-S-SAT(S). The discovery of such dichotomy theorems, for unquantified formulas, has received significant recent attention in the literature [CF+93, CF+94, Cr95, KSW97]. Keywords: NP-hardness; Approximation Algorithms; PSPACE-hardness; Quantified and Stochastic Constraint Satisfaction Problems.
Limit on Saudi Arabia's oil pricing policy: a short-run econometric-simulation model
Bagour, O.S.M.
1985-01-01
Absence of a unified OPEC policy is largely attributed to frequent Saudi Arabian pricing/production decisions to influence oil price changes. Such demonstrated ability in the past prompted many to attribute oil price current downward rigidity to Saudi Arabian unwillingness to increase production. Empirically, this study presents a simultaneous equations oil market model in a simulation setting to test this hypothesis and to predict future oil prices under specific assumptions. Major conclusions are: (1) contrary to popular belief the international oil industry rarely, if ever, operated competitively; (2) the sole association of oil price increases to the embargo of 1973 is an outright distortion of facts; (3) the roots of the so-called energy crisis lie in: (a) post-World War II West European reconstruction, (b) US industrial adjustments from a war to a consumer-oriented economy, (c) the continuously dwindling oil reserves in major industrial countries, and (d) the comparative advantage of location and cost-per-unit of the Middle Eastern oil; (4) barring further market institutionalizations, a per barrel price below $15 by the end of 1990 (in constant 1984 prices) is not unlikely; and (5) future Saudi Arabian pricing/production policies to exert downward pressures on prices could lead to price increases, if perceived to be permanent by the OPEC group excluding Saudi Arabia.
Semiclassical approximation to supersymmetric quantum gravity
Kiefer, Claus; Lueck, Tobias; Moniz, Paulo
2005-08-15
We develop a semiclassical approximation scheme for the constraint equations of supersymmetric canonical quantum gravity. This is achieved by a Born-Oppenheimer type of expansion, in analogy to the case of the usual Wheeler-DeWitt equation. The formalism is only consistent if the states at each order depend on the gravitino field. We recover at consecutive orders the Hamilton-Jacobi equation, the functional Schroedinger equation, and quantum gravitational correction terms to this Schroedinger equation. In particular, the following consequences are found: (i) the Hamilton-Jacobi equation and therefore the background spacetime must involve the gravitino, (ii) a (many-fingered) local time parameter has to be present on super Riem {sigma} (the space of all possible tetrad and gravitino fields) (iii) quantum supersymmetric gravitational corrections affect the evolution of the very early Universe. The physical meaning of these equations and results, in particular, the similarities to and differences from the pure bosonic case, are discussed.
Magnetic reconnection under anisotropic magnetohydrodynamic approximation
Hirabayashi, K.; Hoshino, M.
2013-11-15
We study the formation of slow-mode shocks in collisionless magnetic reconnection by using one- and two-dimensional collisionless MHD codes based on the double adiabatic approximation and the Landau closure model. We bridge the gap between the Petschek-type MHD reconnection model accompanied by a pair of slow shocks and the observational evidence of the rare occasion of in-situ slow shock observations. Our results showed that once magnetic reconnection takes place, a firehose-sense (p{sub ?}>p{sub ?}) pressure anisotropy arises in the downstream region, and the generated slow shocks are quite weak comparing with those in an isotropic MHD. In spite of the weakness of the shocks, however, the resultant reconnection rate is 10%30% higher than that in an isotropic case. This result implies that the slow shock does not necessarily play an important role in the energy conversion in the reconnection system and is consistent with the satellite observation in the Earth's magnetosphere.
Approximate Model for Turbulent Stagnation Point Flow.
Dechant, Lawrence
2016-01-01
Here we derive an approximate turbulent self-similar model for a class of favorable pressure gradient wedge-like flows, focusing on the stagnation point limit. While the self-similar model provides a useful gross flow field estimate this approach must be combined with a near wall model is to determine skin friction and by Reynolds analogy the heat transfer coefficient. The combined approach is developed in detail for the stagnation point flow problem where turbulent skin friction and Nusselt number results are obtained. Comparison to the classical Van Driest (1958) result suggests overall reasonable agreement. Though the model is only valid near the stagnation region of cylinders and spheres it nonetheless provides a reasonable model for overall cylinder and sphere heat transfer. The enhancement effect of free stream turbulence upon the laminar flow is used to derive a similar expression which is valid for turbulent flow. Examination of free stream enhanced laminar flow suggests that the rather than enhancement of a laminar flow behavior free stream disturbance results in early transition to turbulent stagnation point behavior. Excellent agreement is shown between enhanced laminar flow and turbulent flow behavior for high levels, e.g. 5% of free stream turbulence. Finally the blunt body turbulent stagnation results are shown to provide realistic heat transfer results for turbulent jet impingement problems.
COMPLEXITY&APPROXIMABILITY OF QUANTIFIED&STOCHASTIC CONSTRAINT SATISFACTION PROBLEMS
Hunt, H. B.; Marathe, M. V.; Stearns, R. E.
2001-01-01
Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S and T be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SATc(S).) Here, we study simultaneously the complexity of decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. We present simple yet general techniques to characterize simultaneously, the complexity or efficient approximability of a number of versions/variants of the problems SAT(S), Q-SAT(S), S-SAT(S),MAX-Q-SAT(S) etc., for many different such D,C ,S, T. These versions/variants include decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. Our unified approach is based on the following two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic represent ability. Some of the results extend the earlier results in [Pa85,LMP99,CF+93,CF+94O]u r techniques and results reported here also provide significant steps towards obtaining dichotomy theorems, for a number of the problems above, including the problems MAX-&-SAT( S), and MAX-S-SAT(S). The discovery of such dichotomy theorems, for unquantified formulas, has received significant recent attention in the literature [CF+93,CF+94,Cr95,KSW97
Bond selective chemistry beyond the adiabatic approximation
Butler, L.J.
1993-12-01
One of the most important challenges in chemistry is to develop predictive ability for the branching between energetically allowed chemical reaction pathways. Such predictive capability, coupled with a fundamental understanding of the important molecular interactions, is essential to the development and utilization of new fuels and the design of efficient combustion processes. Existing transition state and exact quantum theories successfully predict the branching between available product channels for systems in which each reaction coordinate can be adequately described by different paths along a single adiabatic potential energy surface. In particular, unimolecular dissociation following thermal, infrared multiphoton, or overtone excitation in the ground state yields a branching between energetically allowed product channels which can be successfully predicted by the application of statistical theories, i.e. the weakest bond breaks. (The predictions are particularly good for competing reactions in which when there is no saddle point along the reaction coordinates, as in simple bond fission reactions.) The predicted lack of bond selectivity results from the assumption of rapid internal vibrational energy redistribution and the implicit use of a single adiabatic Born-Oppenheimer potential energy surface for the reaction. However, the adiabatic approximation is not valid for the reaction of a wide variety of energetic materials and organic fuels; coupling between the electronic states of the reacting species play a a key role in determining the selectivity of the chemical reactions induced. The work described below investigated the central role played by coupling between electronic states in polyatomic molecules in determining the selective branching between energetically allowed fragmentation pathways in two key systems.
Silicon carbide fibers and articles including same
Garnier, John E; Griffith, George W
2015-01-27
Methods of producing silicon carbide fibers. The method comprises reacting a continuous carbon fiber material and a silicon-containing gas in a reaction chamber at a temperature ranging from approximately 1500.degree. C. to approximately 2000.degree. C. A partial pressure of oxygen in the reaction chamber is maintained at less than approximately 1.01.times.10.sup.2 Pascal to produce continuous alpha silicon carbide fibers. Continuous alpha silicon carbide fibers and articles formed from the continuous alpha silicon carbide fibers are also disclosed.
Exploring the Random Phase Approximately for materials chemistry and physics
Ruzsinsky, Adrienn
2015-03-23
This proposal focuses on improved accuracy for the delicate energy differences of interest in materials chemistry with the fully nonlocal random phase approximation (RPA) in a density functional context. Could RPA or RPA-like approaches become standard methods of first-principles electronic-structure calculation for atoms, molecules, solids, surfaces, and nano-structures? Direct RPA includes the full exact exchange energy and a nonlocal correlation energy from the occupied and unoccupied Kohn-Sham orbitals and orbital energies, with an approximate but universal description of long-range van der Waals attraction. RPA also improves upon simple pair-wise interaction potentials or vdW density functional theory. This improvement is essential to capture accurate energy differences in metals and different phases of semiconductors. The applications in this proposal are challenges for the simpler approximations of Kohn-Sham density functional theory, which are part of the current “standard model” for quantum chemistry and condensed matter physics. Within this project we already applied RPA on different structural phase transitions on semiconductors, metals and molecules. Although RPA predicts accurate structural parameters, RPA has proven not equally accurate in all kinds of structural phase transitions. Therefore a correction to RPA can be necessary in many cases. We are currently implementing and testing a nonempirical, spatially nonlocal, frequency-dependent model for the exchange-correlation kernel in the adiabatic-connection fluctuation-dissipation context. This kernel predicts a nearly-exact correlation energy for the electron gas of uniform density. If RPA or RPA-like approaches prove to be reliably accurate, then expected increases in computer power may make them standard in the electronic-structure calculations of the future.
Methods of producing adsorption media including a metal oxide
Mann, Nicholas R; Tranter, Troy J
2014-03-04
Methods of producing a metal oxide are disclosed. The method comprises dissolving a metal salt in a reaction solvent to form a metal salt/reaction solvent solution. The metal salt is converted to a metal oxide and a caustic solution is added to the metal oxide/reaction solvent solution to adjust the pH of the metal oxide/reaction solvent solution to less than approximately 7.0. The metal oxide is precipitated and recovered. A method of producing adsorption media including the metal oxide is also disclosed, as is a precursor of an active component including particles of a metal oxide.
Quantitative Analysis of Biofuel Sustainability, Including Land...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Quantitative Analysis of Biofuel Sustainability, Including Land Use Change GHG Emissions Quantitative Analysis of Biofuel Sustainability, Including Land Use Change GHG Emissions ...
How to Solve Schroedinger Problems by Approximating the Potential Function
Ledoux, Veerle; Van Daele, Marnix
2010-09-30
We give a survey over the efforts in the direction of solving the Schroedinger equation by using piecewise approximations of the potential function. Two types of approximating potentials have been considered in the literature, that is piecewise constant and piecewise linear functions. For polynomials of higher degree the approximating problem is not so easy to integrate analytically. This obstacle can be circumvented by using a perturbative approach to construct the solution of the approximating problem, leading to the so-called piecewise perturbation methods (PPM). We discuss the construction of a PPM in its most convenient form for applications and show that different PPM versions (CPM,LPM) are in fact equivalent.
Quasiparticle random-phase approximation with interactions from...
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Quasiparticle random-phase approximation with interactions from the Similarity Renormalization Group Citation Details In-Document Search Title: Quasiparticle random-phase ...
A Multithreaded Algorithm for Network Alignment Via Approximate...
Office of Scientific and Technical Information (OSTI)
The best current approaches are entirely heuristic, and are iterative in nature. They generate real-valued heuristic approximations that must be rounded to find integer solutions. ...
ANALOG QUANTUM NEURON FOR FUNCTIONS APPROXIMATION A. EZHOV; A...
Office of Scientific and Technical Information (OSTI)
FOR FUNCTIONS APPROXIMATION A. EZHOV; A. KHROMOV; G. BERMAN 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; IMPLEMENTATION; NERVE CELLS; WAVEGUIDES We describe a system able...
Meikrantz, David H.; Todd, Terry A.; Riddle, Catherine L.; Law, Jack D.; Peterman, Dean R.; Mincher, Bruce J.; McGrath, Christopher A.; Baker, John D.
2007-11-06
A mixed extractant solvent including calix[4]arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The mixed extractant solvent may be used to remove cesium and strontium from an acidic solution. The DtBu18C6 may be present from approximately 0.01 M to approximately 0.4M, such as from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The mixed extractant solvent may form an organic phase in an extraction system that also includes an aqueous phase. Methods of extracting cesium and strontium as well as strontium alone are also disclosed.
Topic A Note: Includes STEPS Subtopic
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Topic A Note: Includes STEPS Subtopic 33 Total Projects Developing and Enhancing Workforce Training Programs
Properties of the Boltzmann equation in the classical approximation
Tanji, Naoto; Epelbaum, Thomas; Gelis, Francois; Wu, Bin
2014-12-30
We study the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since one has also access to the non-approximated result for comparison.
Properties of the Boltzmann equation in the classical approximation
Epelbaum, Thomas; Gelis, François; Tanji, Naoto; Wu, Bin
2014-12-30
We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since one has also access to the non-approximated result for comparison.
Properties of the Boltzmann equation in the classical approximation
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Epelbaum, Thomas; Gelis, François; Tanji, Naoto; Wu, Bin
2014-12-30
We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since onemore » has also access to the non-approximated result for comparison.« less
Higher-degree linear approximations of nonlinear systems
Karahan, S.
1989-01-01
In this dissertation, the author develops a new method for obtaining higher degree linear approximations of nonlinear control systems. The standard approach in the analysis and synthesis of nonlinear systems is a first order approximation by a linear model. This is usually performed by obtaining a series expansion of the system at some nominal operating point and retaining only the first degree terms in the series. The accuracy of this approximation depends on how far the system moves away from the normal point, and on the relative magnitudes of the higher degree terms in the series expansion. The approximation is achieved by finding an appropriate nonlinear coordinate transformation-feedback pair to perform the higher degree linearization. With the proposed method, one can improve the accuracy of the approximation up to arbitrarily higher degrees, provided certain solvability conditions are satisfied. The Hunt-Su linearizability theorem makes these conditions precise. This approach is similar to Poincare's Normal Form Theorem in formulation, but different in its solution method. After some mathematical background the author derives a set of equations (called the Homological Equations). A solution to this system of linear equations is equivalent to the solution to the problem of approximate linearization. However, it is generally not possible to solve the system of equations exactly. He outlines a method for systematically finding approximate solutions to these equations using singular value decomposition, while minimizing an error with respect to some defined norm.
Communication: Improved pair approximations in local coupled-cluster methods
Schwilk, Max; Werner, Hans-Joachim; Usvyat, Denis
2015-03-28
In local coupled cluster treatments the electron pairs can be classified according to the magnitude of their energy contributions or distances into strong, close, weak, and distant pairs. Different approximations are introduced for the latter three classes. In this communication, an improved simplified treatment of close and weak pairs is proposed, which is based on long-range cancellations of individually slowly decaying contributions in the amplitude equations. Benchmark calculations for correlation, reaction, and activation energies demonstrate that these approximations work extremely well, while pair approximations based on local second-order Møller-Plesset theory can lead to errors that are 1-2 orders of magnitude larger.
Improved approximate formulas for flux from cylindrical and rectangular sources
Wallace, O.J.; Bokharee, S.A.
1993-03-01
This report provides two new approximate formulas for the flux at detector points outside the radial and axial extensions of a homogeneous cylindrical source and improved approximate formulas for the flux at points opposite rectangular surface sources. These formulas extend the range of geometries for which analytic approximations may be used by shield design engineers to make rapid scoping studies and check more extensive calculations for reasonableness. These formulas can be used to support skeptical, independent evaluations and are also valuable teaching tools for introducing shield designers to complex shield analyses.
INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; RADIATION
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interval technical basis document Chiaro, P.J. Jr. 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; RADIATION DETECTORS; RADIATION MONITORS; DOSEMETERS;...
Integral approximations to classical diffusion and smoothed particle hydrodynamics
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Du, Qiang; Lehoucq, R. B.; Tartakovsky, A. M.
2014-12-31
The contribution of the paper is the approximation of a classical diffusion operator by an integral equation with a volume constraint. A particular focus is on classical diffusion problems associated with Neumann boundary conditions. By exploiting this approximation, we can also approximate other quantities such as the flux out of a domain. Our analysis of the model equation on the continuum level is closely related to the recent work on nonlocal diffusion and peridynamic mechanics. In particular, we elucidate the role of a volumetric constraint as an approximation to a classical Neumann boundary condition in the presence of physical boundary.more » The volume-constrained integral equation then provides the basis for accurate and robust discretization methods. As a result, an immediate application is to the understanding and improvement of the Smoothed Particle Hydrodynamics (SPH) method.« less
Second post-Newtonian approximation of Einstein-aether theory
Xie Yi; Huang Tianyi
2008-06-15
In this paper, second post-Newtonian approximation of Einstein-aether theory is obtained by Chandrasekhar's approach. Five parametrized post-Newtonian parameters in first post-Newtonian approximation are presented after a time transformation and they are identical with previous works, in which {gamma}=1, {beta}=1, and two preferred-frame parameters remain. Meanwhile, in second post-Newtonian approximation, a parameter, which represents third order nonlinearity for gravity, is zero--the same as in general relativity. For an application for future deep space laser ranging missions, we reduce the metric coefficients for light propagation in a case of N point masses as a simplified model of the Solar System. The resulting light deflection angle in second post-Newtonian approximation poses another constraint on the Einstein-aether theory.
Exact and approximate Kohn-Sham potentials in ensemble density...
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Title: Exact and approximate Kohn-Sham potentials in ensemble density-functional theory Authors: Yang, Zeng-hui ; Trail, John R. ; Pribram-Jones, Aurora ; Burke, Kieron ; Needs, ...
Berkel, M. van; Hogeweij, G. M. D.; Tamura, N.; Ida, K.; Zwart, H. J.; Inagaki, S.; Baar, M. R. de
2014-11-15
In this paper, a number of new explicit approximations are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in a cylindrical geometry. For this purpose, the harmonic components of heat waves induced by localized deposition of modulated power are used. The approximations are based upon the heat equation in a semi-infinite cylindrical domain. The approximations are based upon continued fractions, asymptotic expansions, and multiple harmonics. The relative error for the different derived approximations is presented for different values of frequency, transport coefficients, and dimensionless radius. Moreover, it is shown how combinations of different explicit formulas can yield good approximations over a wide parameter space for different cases, such as no convection and damping, only damping, and both convection and damping. This paper is the second part (Part II) of a series of three papers. In Part I, the semi-infinite slab approximations have been treated. In Part III, cylindrical approximations are treated for heat waves traveling towards the center of the plasma.
Gas storage materials, including hydrogen storage materials
Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji
2013-02-19
A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.
Communications circuit including a linear quadratic estimator
Ferguson, Dennis D.
2015-07-07
A circuit includes a linear quadratic estimator (LQE) configured to receive a plurality of measurements a signal. The LQE is configured to weight the measurements based on their respective uncertainties to produce weighted averages. The circuit further includes a controller coupled to the LQE and configured to selectively adjust at least one data link parameter associated with a communication channel in response to receiving the weighted averages.
Intentionally Including - Engaging Minorities in Physics Careers |
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Department of Energy Intentionally Including - Engaging Minorities in Physics Careers Intentionally Including - Engaging Minorities in Physics Careers April 24, 2013 - 4:37pm Addthis Joining Director Dot Harris (second from left) were Marlene Kaplan, the Deputy Director of Education and director of EPP, National Oceanic and Atmospheric Administration, Claudia Rankins, a Program Officer with the National Science Foundation and Jim Stith, the past Vice-President of the American Institute of
Gas storage materials, including hydrogen storage materials
Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji
2014-11-25
A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.
Berkel, M. van; Zwart, H. J.; Tamura, N.; Ida, K.; Hogeweij, G. M. D.; Inagaki, S.; Baar, M. R. de
2014-11-15
In this paper, a number of new approximations are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in cylindrical geometry. For this purpose, the harmonic components of heat waves induced by localized deposition of modulated power are used. The approximations are based on semi-infinite slab approximations of the heat equation. The main result is the approximation of χ under the influence of V and τ based on the phase of two harmonics making the estimate less sensitive to calibration errors. To understand why the slab approximations can estimate χ well in cylindrical geometry, the relationships between heat transport models in slab and cylindrical geometry are studied. In addition, the relationship between amplitude and phase with respect to their derivatives, used to estimate χ, is discussed. The results are presented in terms of the relative error for the different derived approximations for different values of frequency, transport coefficients, and dimensionless radius. The approximations show a significant region in which χ, V, and τ can be estimated well, but also regions in which the error is large. Also, it is shown that some compensation is necessary to estimate V and τ in a cylindrical geometry. On the other hand, errors resulting from the simplified assumptions are also discussed showing that estimating realistic values for V and τ based on infinite domains will be difficult in practice. This paper is the first part (Part I) of a series of three papers. In Part II and Part III, cylindrical approximations based directly on semi-infinite cylindrical domain (outward propagating heat pulses) and inward propagating heat pulses in a cylindrical domain, respectively, will be treated.
Scramjet including integrated inlet and combustor
Kutschenreuter, P.H. Jr.; Blanton, J.C.
1992-02-04
This patent describes a scramjet engine. It comprises: a first surface including an aft facing step; a cowl including: a leading edge and a trailing edge; an upper surface and a lower surface extending between the leading edge and the trailing edge; the cowl upper surface being spaced from and generally parallel to the first surface to define an integrated inlet-combustor therebetween having an inlet for receiving and channeling into the inlet-combustor supersonic inlet airflow; means for injecting fuel into the inlet-combustor at the step for mixing with the supersonic inlet airflow for generating supersonic combustion gases; and further including a spaced pari of sidewalls extending between the first surface to the cowl upper surface and wherein the integrated inlet-combustor is generally rectangular and defined by the sidewall pair, the first surface and the cowl upper surface.
Simulating higher-dimensional geometries in GADRAS using approximate one-dimensional solutions.
Thoreson, Gregory G.; Mitchell, Dean James; Harding, Lee T.
2013-02-01
The Gamma Detector Response and Analysis Software (GADRAS) software package is capable of simulating the radiation transport physics for one-dimensional models. Spherical shells are naturally one-dimensional, and have been the focus of development and benchmarking. However, some objects are not spherical in shape, such as cylinders and boxes. These are not one-dimensional. Simulating the radiation transport in two or three dimensions is unattractive because of the extra computation time required. To maintain computational efficiency, higher-dimensional geometries require approximations to simulate them in one-dimension. This report summarizes the theory behind these approximations, tests the theory against other simulations, and compares the results to experimental data. Based on the results, it is recommended that GADRAS users always attempt to approximate reality using spherical shells. However, if fissile material is present, it is imperative that the shape of the one-dimensional model matches the fissile material, including the use of slab and cylinder geometry.
Electric Power Monthly, August 1990. [Glossary included
Not Available
1990-11-29
The Electric Power Monthly (EPM) presents monthly summaries of electric utility statistics at the national, Census division, and State level. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data includes generation by energy source (coal, oil, gas, hydroelectric, and nuclear); generation by region; consumption of fossil fuels for power generation; sales of electric power, cost data; and unusual occurrences. A glossary is included.
Approximate Bisimulation-Based Reduction of Power System Dynamic Models
Stankovic, AM; Dukic, SD; Saric, AT
2015-05-01
In this paper we propose approximate bisimulation relations and functions for reduction of power system dynamic models in differential- algebraic (descriptor) form. The full-size dynamic model is obtained by linearization of the nonlinear transient stability model. We generalize theoretical results on approximate bisimulation relations and bisimulation functions, originally derived for a class of constrained linear systems, to linear systems in descriptor form. An algorithm for transient stability assessment is proposed and used to determine whether the power system is able to maintain the synchronism after a large disturbance. Two benchmark power systems are used to illustrate the proposed algorithm and to evaluate the applicability of approximate bisimulation relations and bisimulation functions for reduction of the power system dynamic models.
Fokker-Planck approximation of monoenergetic transport processes
Boergers, C.; Larsen, E.W.
1994-12-31
For transport problems with highly forward-peaked scattering, the transport equation is often approximated by the Fokker-Planck equation or, if large-angle scattering is deemed sufficiently important, by the Boltzmann-Fokker-Planck equation. In this paper, we state a simple, necessary, and sufficient condition for the validity of the simpler Fokker-Planck approximation for monoenergetic particle transport. We also show that for screened Rutherford scattering, the Fokker-Planck approximation is only marginally valid and is inaccurate unless the scattering is extremely forward peaked. (The same is true for more sophisticated models of elastic scattering of charged particles. In this paper, we restrict ourselves to screened Rutherford scattering for simplicity). More details on the results presented here will be given in forthcoming publications.
Trigonometric Pade approximants for functions with regularly decreasing Fourier coefficients
Labych, Yuliya A; Starovoitov, Alexander P [Gomel State University, Gomel (Belarus)
2009-08-31
Sufficient conditions describing the regular decrease of the coefficients of a Fourier series f(x)=a{sub 0}/2 + {sigma} a{sub n} cos kx are found which ensure that the trigonometric Pade approximants {pi}{sup t}{sub n,m}(x;f) converge to the function f in the uniform norm at a rate which coincides asymptotically with the highest possible one. The results obtained are applied to problems dealing with finding sharp constants for rational approximations. Bibliography: 31 titles.
On the approximation of crack shapes found during inservice inspection
Bhate, S.R.; Chawla, D.S.; Kushwaha, H.S.
1997-04-01
This paper addresses the characterization of axial internal flaw found during inservice inspection of a pipe. J-integral distribution for various flaw shapes is obtained using line spring finite, element method. The peak J-value and its distribution across the crack is found to be characteristic feature of each shape. The triangular shape yields peak J-value away from the center, the point of depth. The elliptic approximation results in large overestimate of J-value for unsymmetric flaws. Triangular approximation is recommended for such flaws so that further service can be obtained from the component.
Noyes, G.W. )
1990-11-01
This paper deals with the development of a weather data base and the performance prediction of a 50-kW dish Stirling system. An analysis of direct solar insolation data for 1985 from the site in Riyadh, Saudi Arabia was made to determine the available solar energy. A parameter study was done of the effects of component efficiencies and operating conditions on instantaneous and yearly average system efficiency using the prepared weather data. The system performance was found to be most affected by wind, mirror reflectivity, and exact placement of the receiver in the focal point of the mirror.
Subterranean barriers including at least one weld
Nickelson, Reva A.; Sloan, Paul A.; Richardson, John G.; Walsh, Stephanie; Kostelnik, Kevin M.
2007-01-09
A subterranean barrier and method for forming same are disclosed, the barrier including a plurality of casing strings wherein at least one casing string of the plurality of casing strings may be affixed to at least another adjacent casing string of the plurality of casing strings through at least one weld, at least one adhesive joint, or both. A method and system for nondestructively inspecting a subterranean barrier is disclosed. For instance, a radiographic signal may be emitted from within a casing string toward an adjacent casing string and the radiographic signal may be detected from within the adjacent casing string. A method of repairing a barrier including removing at least a portion of a casing string and welding a repair element within the casing string is disclosed. A method of selectively heating at least one casing string forming at least a portion of a subterranean barrier is disclosed.
Photoactive devices including porphyrinoids with coordinating additives
Forrest, Stephen R; Zimmerman, Jeramy; Yu, Eric K; Thompson, Mark E; Trinh, Cong; Whited, Matthew; Diev, Vlacheslav
2015-05-12
Coordinating additives are included in porphyrinoid-based materials to promote intermolecular organization and improve one or more photoelectric characteristics of the materials. The coordinating additives are selected from fullerene compounds and organic compounds having free electron pairs. Combinations of different coordinating additives can be used to tailor the characteristic properties of such porphyrinoid-based materials, including porphyrin oligomers. Bidentate ligands are one type of coordinating additive that can form coordination bonds with a central metal ion of two different porphyrinoid compounds to promote porphyrinoid alignment and/or pi-stacking. The coordinating additives can shift the absorption spectrum of a photoactive material toward higher wavelengths, increase the external quantum efficiency of the material, or both.
Electric power monthly, September 1990. [Glossary included
Not Available
1990-12-17
The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)
Nuclear reactor shield including magnesium oxide
Rouse, Carl A.; Simnad, Massoud T.
1981-01-01
An improvement in nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux, the reactor shielding including means providing structural support, neutron moderator material, neutron absorber material and other components as described below, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron.
Rotor assembly including superconducting magnetic coil
Snitchler, Gregory L.; Gamble, Bruce B.; Voccio, John P.
2003-01-01
Superconducting coils and methods of manufacture include a superconductor tape wound concentrically about and disposed along an axis of the coil to define an opening having a dimension which gradually decreases, in the direction along the axis, from a first end to a second end of the coil. Each turn of the superconductor tape has a broad surface maintained substantially parallel to the axis of the coil.
Power generation method including membrane separation
Lokhandwala, Kaaeid A.
2000-01-01
A method for generating electric power, such as at, or close to, natural gas fields. The method includes conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas by means of a membrane separation step. This step creates a leaner, sweeter, drier gas, which is then used as combustion fuel to run a turbine, which is in turn used for power generation.
Approximations of very weak solutions to boundary-value problems.
Berggren, Martin Olof
2003-03-01
Standard weak solutions to the Poisson problem on a bounded domain have square-integrable derivatives, which limits the admissible regularity of inhomogeneous data. The concept of solution may be further weakened in order to define solutions when data is rough, such as for inhomogeneous Dirichlet data that is only square-integrable over the boundary. Such very weak solutions satisfy a nonstandard variational form (u, v) = G(v). A Galerkin approximation combined with an approximation of the right-hand side G defines a finite-element approximation of the very weak solution. Applying conforming linear elements leads to a discrete solution equivalent to the text-book finite-element solution to the Poisson problem in which the boundary data is approximated by L{sub 2}-projections. The L{sub 2} convergence rate of the discrete solution is O(h{sub s}) for some s {element_of} (0,1/2) that depends on the shape of the domain, asserting a polygonal (two-dimensional) or polyhedral (three-dimensional) domain without slits and (only) square-integrable boundary data.
Optical panel system including stackable waveguides
DeSanto, Leonard; Veligdan, James T.
2007-03-06
An optical panel system including stackable waveguides is provided. The optical panel system displays a projected light image and comprises a plurality of planar optical waveguides in a stacked state. The optical panel system further comprises a support system that aligns and supports the waveguides in the stacked state. In one embodiment, the support system comprises at least one rod, wherein each waveguide contains at least one hole, and wherein each rod is positioned through a corresponding hole in each waveguide. In another embodiment, the support system comprises at least two opposing edge structures having the waveguides positioned therebetween, wherein each opposing edge structure contains a mating surface, wherein opposite edges of each waveguide contain mating surfaces which are complementary to the mating surfaces of the opposing edge structures, and wherein each mating surface of the opposing edge structures engages a corresponding complementary mating surface of the opposite edges of each waveguide.
Optical panel system including stackable waveguides
DeSanto, Leonard; Veligdan, James T.
2007-11-20
An optical panel system including stackable waveguides is provided. The optical panel system displays a projected light image and comprises a plurality of planar optical waveguides in a stacked state. The optical panel system further comprises a support system that aligns and supports the waveguides in the stacked state. In one embodiment, the support system comprises at least one rod, wherein each waveguide contains at least one hole, and wherein each rod is positioned through a corresponding hole in each waveguide. In another embodiment, the support system comprises at least two opposing edge structures having the waveguides positioned therebetween, wherein each opposing edge structure contains a mating surface, wherein opposite edges of each waveguide contain mating surfaces which are complementary to the mating surfaces of the opposing edge structures, and wherein each mating surface of the opposing edge structures engages a corresponding complementary mating surface of the opposite edges of each waveguide.
Drapery assembly including insulated drapery liner
Cukierski, Gwendolyn (Ithaca, NY)
1983-01-01
A drapery assembly is disclosed for covering a framed wall opening, the assembly including drapery panels hung on a horizontal traverse rod, the rod having a pair of master slides and means for displacing the master slides between open and closed positions. A pair of insulating liner panels are positioned behind the drapery, the remote side edges of the liner panels being connected with the side portions of the opening frame, and the adjacent side edges of the liner panels being connected with a pair of vertically arranged center support members adapted for sliding movement longitudinally of a horizontal track member secured to the upper horizontal portion of the opening frame. Pivotally arranged brackets connect the center support members with the master slides of the traverse rod whereby movement of the master slides to effect opening and closing of the drapery panels effects simultaneous opening and closing of the liner panels.
Thermovoltaic semiconductor device including a plasma filter
Baldasaro, Paul F.
1999-01-01
A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.
Thermal effects and sudden decay approximation in the curvaton scenario
Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro; Langlois, David; Takahashi, Tomo E-mail: langlois@apc.univ-paris7.fr E-mail: takesako@icrr.u-tokyo.ac.jp
2014-10-01
We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.
Data approximation using a blending type spline construction
Dalmo, Rune; Bratlie, Jostein
2014-11-18
Generalized expo-rational B-splines (GERBS) is a blending type spline construction where local functions at each knot are blended together by C{sup k}-smooth basis functions. One way of approximating discrete regular data using GERBS is by partitioning the data set into subsets and fit a local function to each subset. Partitioning and fitting strategies can be devised such that important or interesting data points are interpolated in order to preserve certain features. We present a method for fitting discrete data using a tensor product GERBS construction. The method is based on detection of feature points using differential geometry. Derivatives, which are necessary for feature point detection and used to construct local surface patches, are approximated from the discrete data using finite differences.
Doorway states in the random-phase approximation
De Pace, A.; Molinari, A.; Weidenmüller, H.A.
2014-12-15
By coupling a doorway state to a sea of random background states, we develop the theory of doorway states in the framework of the random-phase approximation (RPA). Because of the symmetry of the RPA equations, that theory is radically different from the standard description of doorway states in the shell model. We derive the Pastur equation in the limit of large matrix dimension and show that the results agree with those of matrix diagonalization in large spaces. The complexity of the Pastur equation does not allow for an analytical approach that would approximately describe the doorway state. Our numerical results display unexpected features: The coupling of the doorway state with states of opposite energy leads to strong mutual attraction.
The Monte Carlo Independent Column Approximation Model Intercomparison
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Project (McMIP) The Monte Carlo Independent Column Approximation Model Intercomparison Project (McMIP) Barker, Howard Meteorological Service of Canada Cole, Jason Meteorological Service of Canada Raisanen, Petri Finnish Meteorological Institute Pincus, Robert NOAA-CIRES Climate Diagnostics Center Morcrette, Jean-Jacques European Centre for Medium-Range Weather Forecasts Li, Jiangnan Canadian Center for Climate Modelling Stephens, Graeme Colorado State University Vaillancourt, Paul
Crossing contours in the interacting boson approximation (IBA) symmetry triangle
McCutchan, E. A.; Casten, R. F.
2006-11-15
Constant contours of basic observables are discussed in the context of the interacting boson approximation (IBA) symmetry triangle. Contours that exhibit orthogonal crossing within the triangle are presented as a method for determining a set of parameter values for a particular nucleus and trajectories for isotopic chains. A set of contours that highlights a class of nuclei that are outside the two-parameter IBA-1 Hamitonian space is also presented.
Engine lubrication circuit including two pumps
Lane, William H.
2006-10-03
A lubrication pump coupled to the engine is sized such that the it can supply the engine with a predetermined flow volume as soon as the engine reaches a peak torque engine speed. In engines that operate predominately at speeds above the peak torque engine speed, the lubrication pump is often producing lubrication fluid in excess of the predetermined flow volume that is bypassed back to a lubrication fluid source. This arguably results in wasted power. In order to more efficiently lubricate an engine, a lubrication circuit includes a lubrication pump and a variable delivery pump. The lubrication pump is operably coupled to the engine, and the variable delivery pump is in communication with a pump output controller that is operable to vary a lubrication fluid output from the variable delivery pump as a function of at least one of engine speed and lubrication flow volume or system pressure. Thus, the lubrication pump can be sized to produce the predetermined flow volume at a speed range at which the engine predominately operates while the variable delivery pump can supplement lubrication fluid delivery from the lubrication pump at engine speeds below the predominant engine speed range.
Articles including thin film monolayers and multilayers
Li, DeQuan; Swanson, Basil I.
1995-01-01
Articles of manufacture including: (a) a base substrate having an oxide surface layer, and a multidentate ligand, capable of binding a metal ion, attached to the oxide surface layer of the base substrate, (b) a base substrate having an oxide surface layer, a multidentate ligand, capable of binding a metal ion, attached to the oxide surface layer of the base substrate, and a metal species attached to the multidentate ligand, (c) a base substrate having an oxide surface layer, a multidentate ligand, capable of binding a metal ion, attached to the oxide surface layer of the base substrate, a metal species attached to the multidentate ligand, and a multifunctional organic ligand attached to the metal species, and (d) a base substrate having an oxide surface layer, a multidentate ligand, capable of binding a metal ion, attached to the oxide surface layer of the base substrate, a metal species attached to the multidentate ligand, a multifunctional organic ligand attached to the metal species, and a second metal species attached to the multifunctional organic ligand, are provided, such articles useful in detecting the presence of a selected target species, as nonliear optical materials, or as scavengers for selected target species.
Alemi, Mallory; Loring, Roger F.
2015-06-07
The optimized mean-trajectory (OMT) approximation is a semiclassical method for computing vibrational response functions from action-quantized classical trajectories connected by discrete transitions that represent radiation-matter interactions. Here, we extend the OMT to include additional vibrational coherence and energy transfer processes. This generalized approximation is applied to a pair of anharmonic chromophores coupled to a bath. The resulting 2D spectra are shown to reflect coherence transfer between normal modes.
Structural physical approximations of unphysical maps and generalized quantum measurements
Fiurasek, Jaromir
2002-11-01
We investigate properties of the structural physical approximation (SPA) of the partial transposition map recently introduced by Horodecki and Ekert [Phys. Rev. Lett. 89, 127902 (2002)]. We focus on the case of two-qubit states and show that in this case the map has the structure of a generalized quantum measurement followed by the preparation of a suitable output state. We also introduce SPA for a map that transforms two copies of density matrix of a single qubit onto a square of that matrix. We prove that also this map is essentially a generalized quantum measurement.
Compton scattering from positronium and validity of the impulse approximation
Kaliman, Z.; Pisk, K.; Pratt, R. H.
2011-05-15
The cross sections for Compton scattering from positronium are calculated in the range from 1 to 100 keV incident photon energy. The calculations are based on the A{sup 2} term of the photon-electron or photon-positron interaction. Unlike in hydrogen, the scattering occurs from two centers and the interference effect plays an important role for energies below 8 keV. Because of the interference, the criterion for validity of the impulse approximation for positronium is more restrictive compared to that for hydrogen.
Multigroup Free-atom Doppler-broadening Approximation. Experiment
Gray, Mark Girard
2015-11-06
The multigroup energy Doppler-broadening approximation agrees with continuous energy Dopplerbroadening generally to within ten percent for the total cross sections of ^{1}H,^{ 56}Fe, and ^{235}U at 250 lanl. Although this is probably not good enough for broadening from room temperature through the entire temperature range in production use, it is better than any interpolation scheme between temperatures proposed to date, and may be good enough for extrapolation from high temperatures. The method deserves further study since additional improvements are possible.
A multiscale two-point flux-approximation method
Myner, Olav Lie, Knut-Andreas
2014-10-15
A large number of multiscale finite-volume methods have been developed over the past decade to compute conservative approximations to multiphase flow problems in heterogeneous porous media. In particular, several iterative and algebraic multiscale frameworks that seek to reduce the fine-scale residual towards machine precision have been presented. Common for all such methods is that they rely on a compatible primaldual coarse partition, which makes it challenging to extend them to stratigraphic and unstructured grids. Herein, we propose a general idea for how one can formulate multiscale finite-volume methods using only a primal coarse partition. To this end, we use two key ingredients that are computed numerically: (i) elementary functions that correspond to flow solutions used in transmissibility upscaling, and (ii) partition-of-unity functions used to combine elementary functions into basis functions. We exemplify the idea by deriving a multiscale two-point flux-approximation (MsTPFA) method, which is robust with regards to strong heterogeneities in the permeability field and can easily handle general grids with unstructured fine- and coarse-scale connections. The method can easily be adapted to arbitrary levels of coarsening, and can be used both as a standalone solver and as a preconditioner. Several numerical experiments are presented to demonstrate that the MsTPFA method can be used to solve elliptic pressure problems on a wide variety of geological models in a robust and efficient manner.
Study of multiband disordered systems using the typical medium dynamical cluster approximation
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhang, Yi; Terletska, Hanna; Moore, C.; Ekuma, Chinedu; Tam, Ka-Ming; Berlijn, Tom; Ku, Wei; Moreno, Juana; Jarrell, Mark
2015-11-06
We generalize the typical medium dynamical cluster approximation to multiband disordered systems. Using our extended formalism, we perform a systematic study of the nonlocal correlation effects induced by disorder on the density of states and the mobility edge of the three-dimensional two-band Anderson model. We include interband and intraband hopping and an intraband disorder potential. Our results are consistent with those obtained by the transfer matrix and the kernel polynomial methods. We also apply the method to KxFe2-ySe2 with Fe vacancies. Despite the strong vacancy disorder and anisotropy, we find the material is not an Anderson insulator. Moreover our resultsmore » demonstrate the application of the typical medium dynamical cluster approximation method to study Anderson localization in real materials.« less
Study of multiband disordered systems using the typical medium dynamical cluster approximation
Zhang, Yi; Terletska, Hanna; Moore, C.; Ekuma, Chinedu; Tam, Ka-Ming; Berlijn, Tom; Ku, Wei; Moreno, Juana; Jarrell, Mark
2015-11-06
We generalize the typical medium dynamical cluster approximation to multiband disordered systems. Using our extended formalism, we perform a systematic study of the nonlocal correlation effects induced by disorder on the density of states and the mobility edge of the three-dimensional two-band Anderson model. We include interband and intraband hopping and an intraband disorder potential. Our results are consistent with those obtained by the transfer matrix and the kernel polynomial methods. We also apply the method to K_{x}Fe_{2-y}Se_{2} with Fe vacancies. Despite the strong vacancy disorder and anisotropy, we find the material is not an Anderson insulator. Moreover our results demonstrate the application of the typical medium dynamical cluster approximation method to study Anderson localization in real materials.
Gering, Kevin L.; Harrup, Mason K.; Rollins, Harry W.
2015-12-08
An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.
Approximate Weighted Matching On Emerging Manycore and Multithreaded Architectures
Halappanavar, Mahantesh; Feo, John T.; Villa, Oreste; Tumeo, Antonino; Pothen, Alex
2012-11-30
Graph matching is a prototypical combinatorial problem with many applications in computer science and scientific computing, but algorithms for computing optimal matchings are challenging to parallelize. Approximate matching algorithms provide an alternate route for parallelization, and in many contexts compute near-optimal matchings for large-scale graphs. We present sharedmemory parallel implementations for computing half-approximate weighted matching on state-of-the-art multicore (Intel Nehalem and AMD Magny-Cours), manycore (Nvidia Tesla and Nvidia Fermi) and massively multithreaded (Cray XMT) platforms. We provide two implementations: the first implementation uses shared work queues, and is suited to all these platforms; the second implementation is based on dataflow principles, and exploits the architectural features of the Cray XMT. Using a carefully chosen dataset that exhibits characteristics from a wide range of real-world applications, we show scalable performance across different platforms. In particular, for one instance of the input, an R-MAT graph (RMAT-G), we show speedups of: about 32 on 48 cores of an AMD Magny-Cours; 7 on 8 cores of Intel Nehalem; 3 on Nvidia Tesla and 10 on Nvidia Fermi relative to one core of Intel Nehalem; and 60 on 128 processors of Cray XMT. We demonstrate good weak and strong scaling for graphs with up to a billion edges using up to 12, 800 threads. Given the breadth of this work, we focus on simplicity and portability of software rather than excessive fine-tuning for each platform. To the best of our knowledge, this is the first such large-scale study of the half-approximate weighted matching problem on shared-memory platforms. Driven by the critical enabling role of combinatorial algorithms such as matching in scientific computing and the emergence of informatics applications, there is a growing demand to support irregular computations on current and future computing platforms. In this context, we evaluate the capability
Bonatsos, Dennis; Karampagia, S.; Casten, R. F.
2011-05-15
Using a contraction of the SU(3) algebra to the algebra of the rigid rotator in the large-boson-number limit of the interacting boson approximation (IBA) model, a line is found inside the symmetry triangle of the IBA, along which the SU(3) symmetry is preserved. The line extends from the SU(3) vertex to near the critical line of the first-order shape/phase transition separating the spherical and prolate deformed phases, and it lies within the Alhassid-Whelan arc of regularity, the unique valley of regularity connecting the SU(3) and U(5) vertices in the midst of chaotic regions. In addition to providing an explanation for the existence of the arc of regularity, the present line represents an example of an analytically determined approximate symmetry in the interior of the symmetry triangle of the IBA. The method is applicable to algebraic models possessing subalgebras amenable to contraction. This condition is equivalent to algebras in which the equilibrium ground state and its rotational band become energetically isolated from intrinsic excitations, as typified by deformed solutions to the IBA for large numbers of valence nucleons.
Surface wake in the random-phase approximation
Garcia de Abajo, F.J. ); Echenique, P.M. )
1993-11-01
The scalar-electric-potential distribution set up by an ion traveling in the vicinity of a plane solid-vacuum interface, that is, the surface-wake potential, is investigated with the specular-reflection model to describe the response of the surface and with the random-phase approximation for the dielectric function of the bulk material. This permits us to address the study of the low-velocity surface wake: the static potential is found to have a dip at the position of the ion; that dip is shifted towards the direction opposite to the velocity vector for velocities smaller than the threshold of creation of plasmons ([approx]1.3[ital v][sub [ital F
Above-threshold ionization beyond the dipole approximation
Klaiber, Michael; Hatsagortsyan, Karen Z.; Keitel, Christoph H.
2005-03-01
A generalization of the analytical theory of above-threshold ionization in the single active electron approximation is developed while taking into account leading non-dipole and relativistic corrections in the starting Hamiltonian. Special interest is placed on the high energy part of the photoelectron spectrum which consists of a plateau and a characteristic cutoff. It is shown that the correction due to the magnetic component of the laser field gives rise to a decrease of the plateau height, an increase of the maximal cutoff energy, and a drift of the emitted electrons in propagation direction of the laser field. Furthermore, the influence of the relativistic mass shift may become non-neglible by reducing the cutoff energy significantly. Spin effects or the Zitterbewegung play a comparably minor role in the investigated parameter regime of suboptical frequencies and high but not ultra-high laser intensities.
Mixed series in ultraspherical polynomials and their approximation properties
Sharapudinov, I I
2003-04-30
New (mixed) series in ultraspherical polynomials P{sub n}{sup {alpha}}{sup ,{alpha}}(x) are introduced. The basic difference between a mixed series in the polynomials P{sub n}{sup {alpha}}{sup ,{alpha}}(x) and a Fourier series in the same polynomials is as follows: a mixed series contains terms of the form (2{sup r}f{sub r,k}{sup {alpha}})/(k+2{alpha}){sup [r]}) P{sub k+r}{sup {alpha}}{sup -r,{alpha}}{sup -r}(x), where 1{<=}r is an integer and f{sub r,k}{sup {alpha}} is the kth Fourier coefficient of the derivative f{sup (r)}(x) with respect to the ultraspherical polynomials P{sub k}{sup {alpha}}{sup ,{alpha}}(x). It is shown that the partial sums Y{sub n+2r}{sup {alpha}}(f,x) of a mixed series in the polynomial P{sub k}{sup {alpha}}{sup ,{alpha}}(x) contrast favourably with Fourier sums S{sub n}{sup {alpha}}(f,x) in the same polynomials as regards their approximation properties in classes of differentiable and analytic functions, and also in classes of functions of variable smoothness. In particular, the Y{sub n+2r}{sup {alpha}}(f,x) can be used for the simultaneous approximation of a function f(x) and its derivatives of orders up to (r- 1), whereas the S{sub n}{sup {alpha}}(f,x) are not suitable for this purpose.
Liang, Faming; Cheng, Yichen; Lin, Guang
2014-06-13
Simulated annealing has been widely used in the solution of optimization problems. As known by many researchers, the global optima cannot be guaranteed to be located by simulated annealing unless a logarithmic cooling schedule is used. However, the logarithmic cooling schedule is so slow that no one can afford to have such a long CPU time. This paper proposes a new stochastic optimization algorithm, the so-called simulated stochastic approximation annealing algorithm, which is a combination of simulated annealing and the stochastic approximation Monte Carlo algorithm. Under the framework of stochastic approximation Markov chain Monte Carlo, it is shown that the new algorithm can work with a cooling schedule in which the temperature can decrease much faster than in the logarithmic cooling schedule, e.g., a square-root cooling schedule, while guaranteeing the global optima to be reached when the temperature tends to zero. The new algorithm has been tested on a few benchmark optimization problems, including feed-forward neural network training and protein-folding. The numerical results indicate that the new algorithm can significantly outperform simulated annealing and other competitors.
Markov Jump Processes Approximating a Non-Symmetric Generalized Diffusion
Limic, Nedzad
2011-08-15
Consider a non-symmetric generalized diffusion X( Dot-Operator ) in Double-Struck-Capital-R {sup d} determined by the differential operator A(x) = -{Sigma}{sub ij} {partial_derivative}{sub i}a{sub ij}(x){partial_derivative}{sub j} + {Sigma}{sub i} b{sub i}(x){partial_derivative}{sub i}. In this paper the diffusion process is approximated by Markov jump processes X{sub n}( Dot-Operator ), in homogeneous and isotropic grids G{sub n} Subset-Of Double-Struck-Capital-R {sup d}, which converge in distribution in the Skorokhod space D([0,{infinity}), Double-Struck-Capital-R {sup d}) to the diffusion X( Dot-Operator ). The generators of X{sub n}( Dot-Operator ) are constructed explicitly. Due to the homogeneity and isotropy of grids, the proposed method for d{>=}3 can be applied to processes for which the diffusion tensor {l_brace}a{sub ij}(x){r_brace}{sub 11}{sup dd} fulfills an additional condition. The proposed construction offers a simple method for simulation of sample paths of non-symmetric generalized diffusion. Simulations are carried out in terms of jump processes X{sub n}( Dot-Operator ). For piece-wise constant functions a{sub ij} on Double-Struck-Capital-R {sup d} and piece-wise continuous functions a{sub ij} on Double-Struck-Capital-R {sup 2} the construction and principal algorithm are described enabling an easy implementation into a computer code.
Approximate photochemical dynamics of azobenzene with reactive force fields
Li, Yan; Hartke, Bernd
2013-12-14
We have fitted reactive force fields of the ReaxFF type to the ground and first excited electronic states of azobenzene, using global parameter optimization by genetic algorithms. Upon coupling with a simple energy-gap transition probability model, this setup allows for completely force-field-based simulations of photochemical cis?trans- and trans?cis-isomerizations of azobenzene, with qualitatively acceptable quantum yields. This paves the way towards large-scale dynamics simulations of molecular machines, including bond breaking and formation (via the reactive force field) as well as photochemical engines (presented in this work)
On the Validity of Certain Approximations Used in the Modeling of Nuclear EMP
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Farmer, William A.; Cohen, Bruce I.; Eng, Chester D.
2016-04-01
The legacy codes developed for the modeling of EMP, multiple scattering of Compton electrons has typically been modeled by the obliquity factor. A recent publication has examined this approximation in the context of the generated Compton current [W. A. Farmer and A. Friedman, IEEE Trans. Nucl. Sc. 62, 1695 (2015)]. Here, this previous analysis is extended to include the generation of the electromagnetic fields. Obliquity factor predictions are compared with Monte-Carlo models. In using a Monte-Carlo description of scattering, two distributions of scattering angles are considered: Gaussian and a Gaussian with a single-scattering tail. Additionally, legacy codes also neglect themore » radial derivative of the backward-traveling wave for computational efficiency. The neglect of this derivative improperly treats the backward-traveling wave. Moreover, these approximations are examined in the context of a high-altitude burst, and it is shown that in comparison to more complete models, the discrepancy between field amplitudes is roughly two to three percent and between rise-times, 10%. Finally, it is concluded that the biggest factor in determining the rise time of the signal is not the dynamics of the Compton current, but is instead the conductivity.« less
Exact and approximate fermion Green`s functions in QED and QCD
Fried, H.M. [Physics Department, Brown University, Providence, Rhode Island 02912 (United States)] [Physics Department, Brown University, Providence, Rhode Island 02912 (United States); Gabellini, Y. [Institut Non-Lineaire de Nice, 1361, Route des Lucioles, 06560 Valbonne (France)] [Institut Non-Lineaire de Nice, 1361, Route des Lucioles, 06560 Valbonne (France); McKellar, B.H.J. [School of Physics, University of Melbourne, Parkville, Victoria, 3052 (Australia)] [School of Physics, University of Melbourne, Parkville, Victoria, 3052 (Australia)
1995-06-15
That special variant of the Fradkin representation, previously defined for scalar Green`s functions {ital G}{sub {ital c}}({ital x},{ital y}{vert_bar}{ital A}) in an arbitrary potential {ital A}({ital z}), is here extended to the case of vector interactions and spinor Green`s functions of QED and QCD. An exact representation is given which may again be approximated by a finite number {ital N} of quadratures, with the order of magnitude of the errors generated specified in advance, and decreasing with increasing {ital N}. A feature appears for both exact and approximate {ital G}{sub {ital c}}[{ital A}]: the possibility of chaotic behavior of a function central to the representation, which in turn generates chaotic behavior in {ital G}{sub {ital c}}[{ital A}] for certain {ital A}({ital z}). An example is given to show how the general criterion specified here works for a known case of ``quantum chaos,`` in a potential theory context of first quantization. When the full, nonperturbative, radiative corrections of quantum field theory are included, such chaotic effects are removed.
Li, Xinya; Deng, Z. Daniel; USA, Richland Washington; Sun, Yannan; USA, Richland Washington; Martinez, Jayson J.; USA, Richland Washington; Fu, Tao; USA, Richland Washington; McMichael, Geoffrey A.; USA, Richland Washington; Carlson, Thomas J.; USA, Richland Washington
2014-11-27
Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developed using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.
Sergio Alexandre Pinto, Alfred Stadler, Franz Gross
2009-05-01
We present the first calculations of the electromagnetic form factors of 3He and 3H within the framework of the Covariant Spectator Theory (CST). This first exploratory study concentrates on the sensitivity of the form factors to the strength of the scalar meson-nucleon off-shell coupling, known from previous studies to have a strong influence on the three-body binding energy. Results presented here were obtained using the complete impulse approximation (CIA), which includes contributions of relativistic origin that appear as two-body corrections in a non-relativistic framework, such as #28;Z-graphs#29;, but omits other two and three-body currents. We compare our results to non-relativistic calculations augmented by relativistic corrections of O(v/c)2.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Li, Xinya; Deng, Z. Daniel; USA, Richland Washington; Sun, Yannan; USA, Richland Washington; Martinez, Jayson J.; USA, Richland Washington; Fu, Tao; USA, Richland Washington; McMichael, Geoffrey A.; et al
2014-11-27
Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developedmore » using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.« less
Pinto, Sérgio Alexandre; Stadler, Alfred; Gross, Franz
2009-05-01
We present the first calculations of the electromagnetic form factors of ^{3}He and ^{3}H within the framework of the Covariant Spectator Theory (CST). This first exploratory study concentrates on the sensitivity of the form factors to the strength of the scalar meson-nucleon off-shell coupling, known from previous studies to have a strong influence on the three-body binding energy. Results presented here were obtained using the complete impulse approximation (CIA), which includes contributions of relativistic origin that appear as two-body corrections in a non-relativistic framework, such as "Z-graphs," but omits other two and three-body currents. Finally, we compare our results to non-relativistic calculations augmented by relativistic corrections of O(v/c)^{2}.
Pinto, Sergio Alexandre; Stadler, Alfred; Gross, Franz
2009-05-15
We present the first calculations of the electromagnetic form factors of {sup 3}He and {sup 3}H within the framework of the Covariant Spectator Theory (CST). This first exploratory study concentrates on the sensitivity of the form factors to the strength of the scalar meson-nucleon off-shell coupling, known from previous studies to have a strong influence on the three-body binding energy. Results presented here were obtained using the complete impulse approximation (CIA), which includes contributions of relativistic origin that appear as two-body corrections in a nonrelativistic framework, such as 'Z-graphs', but omits other two and three-body currents. We compare our results to nonrelativistic calculations augmented by relativistic corrections of O(v/c){sup 2}.
Alexandre Pinto, SÂ ergio; Stadler, Alfred; Gross, Franz
2009-01-01
We present the first calculations of the electromagnetic form factors of 3He and 3H within the framework of the Covariant Spectator Theory (CST). This first exploratory study concentrates on the sensitivity of the form factors to the strength of the scalar meson-nucleon off-shell coupling, known from previous studies to have a strong influence on the three-body binding energy. Results presented here were obtained using the complete impulse approximation (CIA), which includes contributions of relativistic origin that appear as two-body corrections in a non-relativistic framework, such as ?Z-graphs?, but omits other two and three-body currents. We compare our results to non-relativistic calculations augmented by relativistic corrections of O(v/c)2.
Ou, Qi; Fatehi, Shervin; Alguire, Ethan; Subotnik, Joseph E.; Shao, Yihan
2014-07-14
Working within the Tamm-Dancoff approximation, we calculate the derivative couplings between time-dependent density-functional theory excited states by assuming that the Kohn-Sham superposition of singly excited determinants represents a true electronic wavefunction. All Pulay terms are included in our derivative coupling expression. The reasonability of our approach can be established by noting that, for closely separated electronic states in the infinite basis limit, our final expression agrees exactly with the Chernyak-Mukamel expression (with transition densities from response theory). Finally, we also validate our approach empirically by analyzing the behavior of the derivative couplings around the T{sub 1}/T{sub 2} conical intersection of benzaldehyde.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Biernat, Elmar P.; Gross, Franz; Peña, M. T.; Stadler, Alfred
2015-10-26
The pion form factor is calculated in the framework of the charge-conjugation invariant covariant spectator theory. This formalism is established in Minkowski space, and the calculation is set up in momentum space. In a previous calculation we included only the leading pole coming from the spectator quark (referred to as the relativistic impulse approximation). In this study we also include the contributions from the poles of the quark which interacts with the photon and average over all poles in both the upper and lower half-planes in order to preserve charge conjugation invariance (referred to as the C-symmetric complete impulse approximation).more » We find that for small pion mass these contributions are significant at all values of the four-momentum transfer Q2 but, surprisingly, do not alter the shape obtained from the spectator poles alone.« less
Biernat, Elmar P.; Gross, Franz; Peña, M. T.; Stadler, Alfred
2015-10-26
The pion form factor is calculated in the framework of the charge-conjugation invariant covariant spectator theory. This formalism is established in Minkowski space, and the calculation is set up in momentum space. In a previous calculation we included only the leading pole coming from the spectator quark (referred to as the relativistic impulse approximation). In this study we also include the contributions from the poles of the quark which interacts with the photon and average over all poles in both the upper and lower half-planes in order to preserve charge conjugation invariance (referred to as the C-symmetric complete impulse approximation). We find that for small pion mass these contributions are significant at all values of the four-momentum transfer Q^{2} but, surprisingly, do not alter the shape obtained from the spectator poles alone.
Nuclear Arms Control R&D Consortium includes Los Alamos
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Nuclear Arms Control R&D Consortium includes Los Alamos Nuclear Arms Control R&D Consortium includes Los Alamos A consortium led by the University of Michigan that includes LANL as ...
Solar Energy Education. Reader, Part II. Sun story. [Includes...
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Reader, Part II. Sun story. Includes glossary Citation Details In-Document Search Title: Solar Energy Education. Reader, Part II. Sun story. Includes glossary You are ...
Natural Gas Delivered to Consumers in California (Including Vehicle...
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California (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered to Consumers in California (Including Vehicle Fuel) (Million Cubic Feet) Year Jan Feb Mar Apr May Jun ...
Should Title 24 Ventilation Requirements Be Amended to include...
Office of Scientific and Technical Information (OSTI)
include an Indoor Air Quality Procedure? Citation Details In-Document Search Title: Should Title 24 Ventilation Requirements Be Amended to include an Indoor Air Quality Procedure? ...
Microfluidic devices and methods including porous polymer monoliths...
Office of Scientific and Technical Information (OSTI)
Microfluidic devices and methods including porous polymer monoliths Title: Microfluidic devices and methods including porous polymer monoliths Microfluidic devices and methods ...
Microfluidic devices and methods including porous polymer monoliths...
Office of Scientific and Technical Information (OSTI)
Microfluidic devices and methods including porous polymer monoliths Citation Details In-Document Search Title: Microfluidic devices and methods including porous polymer monoliths ...
Newport News in Review, ch. 47, segment includes TEDF groundbreaking...
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https:www.jlab.orgnewsarticlesnewport-news-review-ch-47-segment-includes-tedf-groundbreaking-event Newport News in Review, ch. 47, segment includes TEDF groundbreaking event...
Property:Number of Plants included in Capacity Estimate | Open...
Plants included in Capacity Estimate Jump to: navigation, search Property Name Number of Plants included in Capacity Estimate Property Type Number Retrieved from "http:...
Property:Number of Plants Included in Planned Estimate | Open...
Number of Plants Included in Planned Estimate Jump to: navigation, search Property Name Number of Plants Included in Planned Estimate Property Type String Description Number of...
FEMP Expands ESPC ENABLE Program to Include More Energy Conservation...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Expands ESPC ENABLE Program to Include More Energy Conservation Measures FEMP Expands ESPC ENABLE Program to Include More Energy Conservation Measures November 13, 2013 - 12:00am...
Natural Gas Delivered to Consumers in Minnesota (Including Vehicle...
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Minnesota (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered to Consumers in Minnesota (Including Vehicle Fuel) (Million Cubic Feet) Year Jan Feb Mar Apr May Jun ...
Quantum Theory of (H,H{Sub 2}) Scattering: Approximate Treatments of Reactive Scattering
DOE R&D Accomplishments [OSTI]
Tang, K. T.; Karplus, M.
1970-10-01
A quantum mechanical study is made of reactive scattering in the (H, H{sub 2}) system. The problem is formulated in terms of a form of the distorted-wave Born approximation (DWBA) suitable for collisions in which all particles have finite mass. For certain incident energies, differential and total cross sections, as well as other attributes of the reactive collisions, (e.g. reaction configuration), are determined. Two limiting models in the DWBA formulation are compared; in one, the molecule is unperturbed by the incoming atom and in the other, the molecule adiabatically follows the incoming atom. For thermal incident energies and semi-empirical interaction potential employed, the adiabatic model seems to be more appropriate. Since the DWBA method is too complicated for a general study of the (H, H{sub 2}) reaction, a much simpler approximation method, the “linear model” is developed. This model is very different in concept from treatments in which the three atoms are constrained to move on a line throughout the collision. The present model includes the full three-dimensional aspect of the collision and it is only the evaluation of the transition matrix element itself that is simplified. It is found that the linear model, when appropriately normalized, gives results in good agreement with that of the DWBA method. By application of this model, the energy dependence, rotational state of dependence and other properties of the total and differential reactions cross sections are determined. These results of the quantum mechanical treatment are compared with the classical calculation for the same potential surface. The most important result is that, in agreement with the classical treatment, the differential cross sections are strongly backward peaked at low energies and shifts in the forward direction as the energy increases. Finally, the implications of the present calculations for a theory of chemical kinetics are discussed.
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space, get 33%-50% power savings Implemented These Ideas in Crayon System Crayon Software Architecture Cairo is a standard, widely-used graphics API Firefox, Graphviz, Poppler, ......
Natural Gas Delivered to Consumers in New Mexico (Including Vehicle...
U.S. Energy Information Administration (EIA) Indexed Site
Mexico (Including Vehicle Fuel) (Million Cubic Feet) Natural Gas Delivered to Consumers in New Mexico (Including Vehicle Fuel) (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul ...
SWS Online Tool now includes Multifamily Content, plus a How...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
SWS Online Tool now includes Multifamily Content, plus a How-To Webinar SWS Online Tool now includes Multifamily Content, plus a How-To Webinar This announcement contains ...
Quantitative Analysis of Biofuel Sustainability, Including Land Use Change
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
GHG Emissions | Department of Energy Quantitative Analysis of Biofuel Sustainability, Including Land Use Change GHG Emissions Quantitative Analysis of Biofuel Sustainability, Including Land Use Change GHG Emissions Plenary V: Biofuels and Sustainability: Acknowledging Challenges and Confronting Misconceptions Quantitative Analysis of Biofuel Sustainability, Including Land Use Change GHG Emissions Jennifer B. Dunn, Energy Systems and Sustainability Analyst, Argonne National Laboratory
A simple approximation for the current-voltage characteristics of high-power, relativistic diodes
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Ekdahl, Carl
2016-06-10
A simple approximation for the current-voltage characteristics of a relativistic electron diode is presented. The approximation is accurate from non-relativistic through relativistic electron energies. Although it is empirically developed, it has many of the fundamental properties of the exact diode solutions. Lastly, the approximation is simple enough to be remembered and worked on almost any pocket calculator, so it has proven to be quite useful on the laboratory floor.
Nuclear relativistic Hartree-Fock calculations including pions interacting with a scalar field
Marcos, S.; Lopez-Quelle, M.; Niembro, R.; Savushkin, L. N.
2012-10-20
The effect of pions on the nuclear shell structure is analyzed in a relativistic Hartree-Fock approximation (RHFA). The Lagrangian includes, in particular, a mixture of {pi}N pseudoscalar (PS) and pseudovector (PV) couplings, self-interactions of the scalar field {sigma} and a {sigma} - {pi} interaction that dresses pions with an effective mass (m*{sub {pi}}). It is found that an increase of m*{sub {pi}} strongly reduces the unrealistic effect of pions, keeping roughly unchanged their contribution to the total binding energy.
Percentage of Total Natural Gas Commercial Deliveries included in Prices
U.S. Energy Information Administration (EIA) Indexed Site
City Gate Price Residential Price Percentage of Total Residential Deliveries included in Prices Commercial Price Percentage of Total Commercial Deliveries included in Prices Industrial Price Percentage of Total Industrial Deliveries included in Prices Electric Power Price Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Data Series Area Jan-16 Feb-16 Mar-16 Apr-16 May-16 Jun-16 View History U.S.
DOE Releases Request for Information on Critical Materials, Including Fuel
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Cell Platinum Group Metal Catalysts | Department of Energy Releases Request for Information on Critical Materials, Including Fuel Cell Platinum Group Metal Catalysts DOE Releases Request for Information on Critical Materials, Including Fuel Cell Platinum Group Metal Catalysts February 17, 2016 - 3:03pm Addthis The U.S. Department of Energy (DOE) has released a Request for Information (RFI) on critical materials in the energy sector, including fuel cell platinum group metal catalysts. The RFI
Microfluidic devices and methods including porous polymer monoliths
Office of Scientific and Technical Information (OSTI)
(Patent) | SciTech Connect Microfluidic devices and methods including porous polymer monoliths Citation Details In-Document Search Title: Microfluidic devices and methods including porous polymer monoliths Microfluidic devices and methods including porous polymer monoliths are described. Polymerization techniques may be used to generate porous polymer monoliths having pores defined by a liquid component of a fluid mixture. The fluid mixture may contain iniferters and the resulting porous
Percentage of Total Natural Gas Industrial Deliveries included in Prices
U.S. Energy Information Administration (EIA) Indexed Site
Pipeline and Distribution Use Price City Gate Price Residential Price Percentage of Total Residential Deliveries included in Prices Commercial Price Percentage of Total Commercial Deliveries included in Prices Industrial Price Percentage of Total Industrial Deliveries included in Prices Vehicle Fuel Price Electric Power Price Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Data Series Area 2010
Percentage of Total Natural Gas Industrial Deliveries included in Prices
U.S. Energy Information Administration (EIA) Indexed Site
City Gate Price Residential Price Percentage of Total Residential Deliveries included in Prices Commercial Price Percentage of Total Commercial Deliveries included in Prices Industrial Price Percentage of Total Industrial Deliveries included in Prices Electric Power Price Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Data Series Area Jan-16 Feb-16 Mar-16 Apr-16 May-16 Jun-16 View History U.S.
Percentage of Total Natural Gas Residential Deliveries included in Prices
U.S. Energy Information Administration (EIA) Indexed Site
City Gate Price Residential Price Percentage of Total Residential Deliveries included in Prices Commercial Price Percentage of Total Commercial Deliveries included in Prices Industrial Price Percentage of Total Industrial Deliveries included in Prices Electric Power Price Period: Monthly Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Data Series Area Jan-16 Feb-16 Mar-16 Apr-16 May-16 Jun-16 View History U.S.
Introduction to Small-Scale Wind Energy Systems (Including RETScreen...
Case Study) (Webinar) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Introduction to Small-Scale Wind Energy Systems (Including RETScreen Case Study) (Webinar) Focus...
Natural Gas Deliveries to Commercial Consumers (Including Vehicle...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
California (Million Cubic Feet) Natural Gas Deliveries to Commercial Consumers (Including Vehicle Fuel through 1996) in California (Million Cubic Feet) Year Jan Feb Mar Apr May Jun ...
Numerical simulations for low energy nuclear reactions including...
Office of Scientific and Technical Information (OSTI)
Numerical simulations for low energy nuclear reactions including direct channels to validate statistical models Citation Details In-Document Search Title: Numerical simulations for ...
U-182: Microsoft Windows Includes Some Invalid Certificates
Broader source: Energy.gov [DOE]
The operating system includes some invalid intermediate certificates. The vulnerability is due to the certificate authorities and not the operating system itself.
Numerical simulations for low energy nuclear reactions including...
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Numerical simulations for low energy nuclear reactions including direct channels to ... Visit OSTI to utilize additional information resources in energy science and technology. A ...
Microfluidic devices and methods including porous polymer monoliths...
Office of Scientific and Technical Information (OSTI)
The fluid mixture may contain iniferters and the resulting porous polymer monolith may include surfaces terminated with iniferter species. Capture molecules may then be grafted to ...
DOE Releases Request for Information on Critical Materials, Including...
Broader source: Energy.gov (indexed) [DOE]
including fuel cell platinum group metal catalysts. ... on issues related to the demand, supply, opportunities for ... Announces Second RFI on Rare Earth Metals DOE Announces RFI ...
Search for Earth-like planets includes LANL star analysis
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their interiors. Consortium team members at Los Alamos include Joyce Ann Guzik, Paul Bradley, Arthur N. Cox, and Kim Simmons. They will help interpret the stellar oscillation...
Including Retro-Commissioning in Federal Energy Savings Performance Contracts
Broader source: Energy.gov [DOE]
Document describes guidance on the importance of (and steps to) including retro-commissioning in federal energy savings performance contracts (ESPCs).
Measuring and modeling the lifetime of nitrous oxide including...
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Published Article: Measuring and modeling the lifetime of nitrous oxide including its variability: NITROUS OXIDE AND ITS CHANGING LIFETIME Prev Next Title: Measuring and ...
Introduction to Small-Scale Photovoltaic Systems (Including RETScreen...
Photovoltaic Systems (Including RETScreen Case Study) (Webinar) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Introduction to Small-Scale Photovoltaic Systems...
Comparison of Joint Modeling Approaches Including Eulerian Sliding...
Office of Scientific and Technical Information (OSTI)
Eulerian Sliding Interfaces Citation Details In-Document Search Title: Comparison of Joint Modeling Approaches Including Eulerian Sliding Interfaces You are accessing a ...
Quasichemical analysis of the cluster-pair approximation for the thermodynamics of proton hydration
Pollard, Travis; Beck, Thomas L.
2014-06-14
A theoretical analysis of the cluster-pair approximation (CPA) is presented based on the quasichemical theory of solutions. The sought single-ion hydration free energy of the proton includes an interfacial potential contribution by definition. It is shown, however, that the CPA involves an extra-thermodynamic assumption that does not guarantee uniform convergence to a bulk free energy value with increasing cluster size. A numerical test of the CPA is performed using the classical polarizable AMOEBA force field and supporting quantum chemical calculations. The enthalpy and free energy differences are computed for the kosmotropic Na{sup +}/F{sup −} ion pair in water clusters of size n = 5, 25, 105. Additional calculations are performed for the chaotropic Rb{sup +}/I{sup −} ion pair. A small shift in the proton hydration free energy and a larger shift in the hydration enthalpy, relative to the CPA values, are predicted based on the n = 105 simulations. The shifts arise from a combination of sequential hydration and interfacial potential effects. The AMOEBA and quantum chemical results suggest an electrochemical surface potential of water in the range −0.4 to −0.5 V. The physical content of single-ion free energies and implications for ion-water force field development are also discussed.
Regional Economic Accounting (REAcct). A software tool for rapidly approximating economic impacts
Ehlen, Mark Andrew; Vargas, Vanessa N.; Loose, Verne William; Starks, Shirley J.; Ellebracht, Lory A.
2011-07-01
This paper describes the Regional Economic Accounting (REAcct) analysis tool that has been in use for the last 5 years to rapidly estimate approximate economic impacts for disruptions due to natural or manmade events. It is based on and derived from the well-known and extensively documented input-output modeling technique initially presented by Leontief and more recently further developed by numerous contributors. REAcct provides county-level economic impact estimates in terms of gross domestic product (GDP) and employment for any area in the United States. The process for using REAcct incorporates geospatial computational tools and site-specific economic data, permitting the identification of geographic impact zones that allow differential magnitude and duration estimates to be specified for regions affected by a simulated or actual event. Using these data as input to REAcct, the number of employees for 39 directly affected economic sectors (including 37 industry production sectors and 2 government sectors) are calculated and aggregated to provide direct impact estimates. Indirect estimates are then calculated using Regional Input-Output Modeling System (RIMS II) multipliers. The interdependent relationships between critical infrastructures, industries, and markets are captured by the relationships embedded in the inputoutput modeling structure.
Nonequilibrium chiral fluid dynamics including dissipation and noise
Nahrgang, Marlene; Herold, Christoph; Bleicher, Marcus; Leupold, Stefan
2011-08-15
We present a consistent theoretical approach for the study of nonequilibrium effects in chiral fluid dynamics within the framework of the linear {sigma} model with constituent quarks. Treating the quarks as an equilibrated heat bath, we use the influence functional formalism to obtain a Langevin equation for the {sigma} field. This allows us to calculate the explicit form of the damping coefficient and the noise correlators. For a self-consistent derivation of both the dynamics of the {sigma} field and the quark fluid, we have to employ the 2PI (two-particle irreducible) effective action formalism. The energy dissipation from the field to the fluid is treated in the exact formalism of the 2PI effective action where a conserved energy-momentum tensor can be constructed. We derive its form and comment on approximations generating additional terms in the energy-momentum balance of the entire system.
Wu, H.; Wang, R.; Liu, Y.; Zhao, E. , P.O. Box 8730, Beijing Physics Department, Suzhou University, Suzhou Institute of High Energy Physics, Academia Sinica, Beijing Institute of Theoretical Physics, Academia Sinica, Beijing )
1992-04-01
The double-charge-exchange (DCX) reaction with Ca isotopes as targets is studied by employing the interacting-boson approximation (IBA). A comparison between the IBA and the shell-model results shows that IBA is a good approximation of the shell model in describing the DCX reactions.
Solar Energy Education. Reader, Part II. Sun story. [Includes glossary
Not Available
1981-05-01
Magazine articles which focus on the subject of solar energy are presented. The booklet prepared is the second of a four part series of the Solar Energy Reader. Excerpts from the magazines include the history of solar energy, mythology and tales, and selected poetry on the sun. A glossary of energy related terms is included. (BCS)
Microfluidic devices and methods including porous polymer monoliths
Hatch, Anson V.; Sommer, Gregory j.; Singh, Anup K.; Wang, Ying-Chih; Abhyankar, Vinay
2015-12-01
Microfluidic devices and methods including porous polymer monoliths are described. Polymerization techniques may be used to generate porous polymer monoliths having pores defined by a liquid component of a fluid mixture. The fluid mixture may contain iniferters and the resulting porous polymer monolith may include surfaces terminated with iniferter species. Capture molecules may then be grafted to the monolith pores.
Microfluidic devices and methods including porous polymer monoliths
Hatch, Anson V; Sommer, Gregory J; Singh, Anup K; Wang, Ying-Chih; Abhyankar, Vinay V
2014-04-22
Microfluidic devices and methods including porous polymer monoliths are described. Polymerization techniques may be used to generate porous polymer monoliths having pores defined by a liquid component of a fluid mixture. The fluid mixture may contain iniferters and the resulting porous polymer monolith may include surfaces terminated with iniferter species. Capture molecules may then be grafted to the monolith pores.
Momentum and energy approximations for elementary squeeze-film damper flows
Crandall, S.H.; El-shafei, A.
1993-09-01
To provide understanding of the effects of inertia on squeeze-film damper performance, two elementary flow patterns are studied. These elementary flows each depend on a single generalized motion coordinate whereas general planar motions of a damper are described by two independent generalized coordinates. Momentum and energy approximations for the elementary flows are compared with exact solutions. It is shown that the energy approximation, not previously applied to squeeze films, is superior to the momentum approximation in that at low Reynolds number the energy approximations agree with the exact solutions to first order in the Reynolds number whereas there are 20 percent errors in the first-order terms of the momentum approximations. 17 refs.
Articles which include chevron film cooling holes, and related processes
Bunker, Ronald Scott; Lacy, Benjamin Paul
2014-12-09
An article is described, including an inner surface which can be exposed to a first fluid; an inlet; and an outer surface spaced from the inner surface, which can be exposed to a hotter second fluid. The article further includes at least one row or other pattern of passage holes. Each passage hole includes an inlet bore extending through the substrate from the inlet at the inner surface to a passage hole-exit proximate to the outer surface, with the inlet bore terminating in a chevron outlet adjacent the hole-exit. The chevron outlet includes a pair of wing troughs having a common surface region between them. The common surface region includes a valley which is adjacent the hole-exit; and a plateau adjacent the valley. The article can be an airfoil. Related methods for preparing the passage holes are also described.
Turbomachine injection nozzle including a coolant delivery system
Zuo, Baifang (Simpsonville, SC)
2012-02-14
An injection nozzle for a turbomachine includes a main body having a first end portion that extends to a second end portion defining an exterior wall having an outer surface. A plurality of fluid delivery tubes extend through the main body. Each of the plurality of fluid delivery tubes includes a first fluid inlet for receiving a first fluid, a second fluid inlet for receiving a second fluid and an outlet. The injection nozzle further includes a coolant delivery system arranged within the main body. The coolant delivery system guides a coolant along at least one of a portion of the exterior wall and around the plurality of fluid delivery tubes.
Regnier, D.; Verriere, M.; Dubray, N.; Schunck, N.
2015-11-30
In this study, we describe the software package FELIX that solves the equations of the time-dependent generator coordinate method (TDGCM) in NN-dimensions (N ≥ 1) under the Gaussian overlap approximation. The numerical resolution is based on the Galerkin finite element discretization of the collective space and the Crank–Nicolson scheme for time integration. The TDGCM solver is implemented entirely in C++. Several additional tools written in C++, Python or bash scripting language are also included for convenience. In this paper, the solver is tested with a series of benchmarks calculations. We also demonstrate the ability of our code to handle a realistic calculation of fission dynamics.
Removal of mineral matter including pyrite from coal
Reggel, Leslie; Raymond, Raphael; Blaustein, Bernard D.
1976-11-23
Mineral matter, including pyrite, is removed from coal by treatment of the coal with aqueous alkali at a temperature of about 175.degree. to 350.degree. C, followed by acidification with strong acid.
Example Retro-Commissioning Scope of Work to Include Services...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Services as Part of an ESPC Investment-Grade Audit Example Retro-Commissioning Scope of Work to Include Services as Part of an ESPC Investment-Grade Audit Document offers a ...
Natural Gas Deliveries to Commercial Consumers (Including Vehicle...
U.S. Energy Information Administration (EIA) Indexed Site
Mexico (Million Cubic Feet) Natural Gas Deliveries to Commercial Consumers (Including Vehicle Fuel through 1996) in New Mexico (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul ...
Including Retro-Commissioning in Federal Energy Savings Performance...
the cost of the survey. Developing a detailed scope of work and a fixed price for this work is important to eliminate risk to the Agency and the ESCo. Including a detailed scope...
T-603: Mac OS X Includes Some Invalid Comodo Certificates
Office of Energy Efficiency and Renewable Energy (EERE)
The operating system includes some invalid certificates. The vulnerability is due to the invalid certificates and not the operating system itself. Other browsers, applications, and operating systems are affected.
Energy Department Expands Gas Gouging Reporting System to Include...
Expands Gas Gouging Reporting System to Include 1-800 Number: 1-800-244-3301 Energy Department Expands Gas ... of reformulated gasoline in storage and is already helping to ...
Natural Gas Delivered to Consumers in Ohio (Including Vehicle...
U.S. Energy Information Administration (EIA) Indexed Site
Natural Gas Delivered to Consumers in Ohio (Including Vehicle Fuel) (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2001 136,340 110,078 102,451 66,525 ...
Hybrid powertrain system including smooth shifting automated transmission
Beaty, Kevin D.; Nellums, Richard A.
2006-10-24
A powertrain system is provided that includes a prime mover and a change-gear transmission having an input, at least two gear ratios, and an output. The powertrain system also includes a power shunt configured to route power applied to the transmission by one of the input and the output to the other one of the input and the output. A transmission system and a method for facilitating shifting of a transmission system are also provided.
Prevention of Harassment (Including Sexual Harassment) and Retaliation
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Policy Statement | Department of Energy Prevention of Harassment (Including Sexual Harassment) and Retaliation Policy Statement Prevention of Harassment (Including Sexual Harassment) and Retaliation Policy Statement DOE Policy for Preventing Harassment in the Workplace Harassment Policy July 2011.pdf (112.57 KB) More Documents & Publications Policy Statement on Equal Employment Opportunity, Harassment, and Retaliation Equal Employment Opportunity and Diversity Policy Statement VWA-0039 -
DOE Revises its NEPA Regulations, Including Categorical Exclusions |
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Department of Energy Revises its NEPA Regulations, Including Categorical Exclusions DOE Revises its NEPA Regulations, Including Categorical Exclusions September 30, 2011 - 2:30pm Addthis On September 27, 2011, the Department of Energy (DOE) approved revisions to its National Environmental Policy Act (NEPA) regulations, and on September 28th, submitted the revisions to the Federal Register. The final regulations, which become effective 30 days after publication in the Federal Register, are
Limited Personal Use of Government Office Equipment including Information Technology
Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]
2005-01-07
The Order establishes requirements and assigns responsibilities for employees' limited personal use of Government resources (office equipment and other resources including information technology) within DOE, including NNSA. The Order is required to provide guidance on appropriate and inappropriate uses of Government resources. This Order was certified 04/23/2009 as accurate and continues to be relevant and appropriate for use by the Department. Certified 4-23-09. No cancellation.
Thermodynamic Advantages of Low Temperature Combustion Engines Including
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
the Use of Low Heat Rejection Concepts | Department of Energy Advantages of Low Temperature Combustion Engines Including the Use of Low Heat Rejection Concepts Thermodynamic Advantages of Low Temperature Combustion Engines Including the Use of Low Heat Rejection Concepts Thermodynamic cycle simulation was used to evaluate low temperature combustion in systematic and sequential fashion to base engine design. deer10_caton.pdf (462.23 KB) More Documents & Publications Boosted HCCI for High
Solar Energy Education. Reader, Part II. Sun story. [Includes glossary]
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
(Technical Report) | SciTech Connect Reader, Part II. Sun story. [Includes glossary] Citation Details In-Document Search Title: Solar Energy Education. Reader, Part II. Sun story. [Includes glossary] × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and
Solar Energy Education. Renewable energy: a background text. [Includes
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
glossary] (Technical Report) | SciTech Connect energy: a background text. [Includes glossary] Citation Details In-Document Search Title: Solar Energy Education. Renewable energy: a background text. [Includes glossary] × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy
Convergence properties of polynomial chaos approximations for L2 random variables.
Field, Richard V., Jr. (.,; .); Grigoriu, Mircea (Cornell University, Ithaca, NY)
2007-03-01
Polynomial chaos (PC) representations for non-Gaussian random variables are infinite series of Hermite polynomials of standard Gaussian random variables with deterministic coefficients. For calculations, the PC representations are truncated, creating what are herein referred to as PC approximations. We study some convergence properties of PC approximations for L{sub 2} random variables. The well-known property of mean-square convergence is reviewed. Mathematical proof is then provided to show that higher-order moments (i.e., greater than two) of PC approximations may or may not converge as the number of terms retained in the series, denoted by n, grows large. In particular, it is shown that the third absolute moment of the PC approximation for a lognormal random variable does converge, while moments of order four and higher of PC approximations for uniform random variables do not converge. It has been previously demonstrated through numerical study that this lack of convergence in the higher-order moments can have a profound effect on the rate of convergence of the tails of the distribution of the PC approximation. As a result, reliability estimates based on PC approximations can exhibit large errors, even when n is large. The purpose of this report is not to criticize the use of polynomial chaos for probabilistic analysis but, rather, to motivate the need for further study of the efficacy of the method.
First and second order approximations to stage numbers in multicomponent enrichment cascades
Scopatz, A.
2013-07-01
This paper describes closed form, Taylor series approximations to the number product stages in a multicomponent enrichment cascade. Such closed form approximations are required when a symbolic, rather than a numeric, algorithm is used to compute the optimal cascade state. Both first and second order approximations were implemented. The first order solution was found to be grossly incorrect, having the wrong functional form over the entire domain. On the other hand, the second order solution shows excellent agreement with the 'true' solution over the domain of interest. An implementation of the symbolic, second order solver is available in the free and open source PyNE library. (authors)
Including environmental concerns in management strategies for depleted uranium hexafluoride
Goldberg, M.; Avci, H.I.; Bradley, C.E.
1995-12-31
One of the major programs within the Office of Nuclear Energy, Science, and Technology of the US Department of Energy (DOE) is the depleted uranium hexafluoride (DUF{sub 6}) management program. The program is intended to find a long-term management strategy for the DUF{sub 6} that is currently stored in approximately 46,400 cylinders at Paducah, KY; Portsmouth, OH; and Oak Ridge, TN, USA. The program has four major components: technology assessment, engineering analysis, cost analysis, and the environmental impact statement (EIS). From the beginning of the program, the DOE has incorporated the environmental considerations into the process of strategy selection. Currently, the DOE has no preferred alternative. The results of the environmental impacts assessment from the EIS, as well as the results from the other components of the program, will be factored into the strategy selection process. In addition to the DOE`s current management plan, other alternatives continued storage, reuse, or disposal of depleted uranium, will be considered in the EIS. The EIS is expected to be completed and issued in its final form in the fall of 1997.
A model for heterogeneous materials including phase transformations
Addessio, F.L.; Clements, B.E.; Williams, T.O.
2005-04-15
A model is developed for particulate composites, which includes phase transformations in one or all of the constituents. The model is an extension of the method of cells formalism. Representative simulations for a single-phase, brittle particulate (SiC) embedded in a ductile material (Ti), which undergoes a solid-solid phase transformation, are provided. Also, simulations for a tungsten heavy alloy (WHA) are included. In the WHA analyses a particulate composite, composed of tungsten particles embedded in a tungsten-iron-nickel alloy matrix, is modeled. A solid-liquid phase transformation of the matrix material is included in the WHA numerical calculations. The example problems also demonstrate two approaches for generating free energies for the material constituents. Simulations for volumetric compression, uniaxial strain, biaxial strain, and pure shear are used to demonstrate the versatility of the model.
Insight into organic reactions from the direct random phase approximation and its corrections
Ruzsinszky, Adrienn; Zhang, Igor Ying; Scheffler, Matthias
2015-10-14
The performance of the random phase approximation (RPA) and beyond-RPA approximations for the treatment of electron correlation is benchmarked on three different molecular test sets. The test sets are chosen to represent three typical sources of error which can contribute to the failure of most density functional approximations in chemical reactions. The first test set (atomization and n-homodesmotic reactions) offers a gradually increasing balance of error from the chemical environment. The second test set (Diels-Alder reaction cycloaddition = DARC) reflects more the effect of weak dispersion interactions in chemical reactions. Finally, the third test set (self-interaction error 11 = SIE11) represents reactions which are exposed to noticeable self-interaction errors. This work seeks to answer whether any one of the many-body approximations considered here successfully addresses all these challenges.
Far-Field Approximation in the Generalized Geometry Holdup (GGH) Model
Oberer, R. B.; Gunn, C. A.; Chiang, L.G.
2006-09-07
Quantitative gamma spectrometry measurements of uranium frequently require corrections for attenuation by an equipment or container layer and by the uranium bearing material itself. It is common to correct for attenuation using the ''far-field approximation''. Under this approximation, the minimum thickness of equipment or material is used for the correction rather than an average thickness over the detector field-of-view. In reality this aspect of the far-field approximation is really a narrow field-of-view approximation. The price of this simplification is the introduction of a bias. This bias will be investigated in this paper. In addition, there is a distance dependence of the radial response of a detector. This dependence will also be investigated.
Horowitz, Jordan M.
2015-07-28
The stochastic thermodynamics of a dilute, well-stirred mixture of chemically reacting species is built on the stochastic trajectories of reaction events obtained from the chemical master equation. However, when the molecular populations are large, the discrete chemical master equation can be approximated with a continuous diffusion process, like the chemical Langevin equation or low noise approximation. In this paper, we investigate to what extent these diffusion approximations inherit the stochastic thermodynamics of the chemical master equation. We find that a stochastic-thermodynamic description is only valid at a detailed-balanced, equilibrium steady state. Away from equilibrium, where there is no consistent stochastic thermodynamics, we show that one can still use the diffusive solutions to approximate the underlying thermodynamics of the chemical master equation.
Solar Energy Education. Renewable energy: a background text. [Includes glossary
Not Available
1985-01-01
Some of the most common forms of renewable energy are presented in this textbook for students. The topics include solar energy, wind power hydroelectric power, biomass ocean thermal energy, and tidal and geothermal energy. The main emphasis of the text is on the sun and the solar energy that it yields. Discussions on the sun's composition and the relationship between the earth, sun and atmosphere are provided. Insolation, active and passive solar systems, and solar collectors are the subtopics included under solar energy. (BCS)
Metal vapor laser including hot electrodes and integral wick
Ault, E.R.; Alger, T.W.
1995-03-07
A metal vapor laser, specifically one utilizing copper vapor, is disclosed herein. This laser utilizes a plasma tube assembly including a thermally insulated plasma tube containing a specific metal, e.g., copper, and a buffer gas therein. The laser also utilizes means including hot electrodes located at opposite ends of the plasma tube for electrically exciting the metal vapor and heating its interior to a sufficiently high temperature to cause the metal contained therein to vaporize and for subjecting the vapor to an electrical discharge excitation in order to lase. The laser also utilizes external wicking arrangements, that is, wicking arrangements located outside the plasma tube. 5 figs.
Metal vapor laser including hot electrodes and integral wick
Ault, Earl R.; Alger, Terry W.
1995-01-01
A metal vapor laser, specifically one utilizing copper vapor, is disclosed herein. This laser utilizes a plasma tube assembly including a thermally insulated plasma tube containing a specific metal, e.g., copper, and a buffer gas therein. The laser also utilizes means including hot electrodes located at opposite ends of the plasma tube for electrically exciting the metal vapor and heating its interior to a sufficiently high temperature to cause the metal contained therein to vaporize and for subjecting the vapor to an electrical discharge excitation in order to lase. The laser also utilizes external wicking arrangements, that is, wicking arrangements located outside the plasma tube.
DOE Considers Natural Gas Utility Service Options: Proposal Includes
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
30-mile Natural Gas Pipeline from Pasco to Hanford | Department of Energy Considers Natural Gas Utility Service Options: Proposal Includes 30-mile Natural Gas Pipeline from Pasco to Hanford DOE Considers Natural Gas Utility Service Options: Proposal Includes 30-mile Natural Gas Pipeline from Pasco to Hanford January 23, 2012 - 12:00pm Addthis Media Contacts Cameron Hardy, DOE , (509) 376-5365, Cameron.Hardy@rl.doe.gov RICHLAND, WASH. - The U.S. Department of Energy (DOE) is considering
Thin film solar cell including a spatially modulated intrinsic layer
Guha, Subhendu; Yang, Chi-Chung; Ovshinsky, Stanford R.
1989-03-28
One or more thin film solar cells in which the intrinsic layer of substantially amorphous semiconductor alloy material thereof includes at least a first band gap portion and a narrower band gap portion. The band gap of the intrinsic layer is spatially graded through a portion of the bulk thickness, said graded portion including a region removed from the intrinsic layer-dopant layer interfaces. The band gap of the intrinsic layer is always less than the band gap of the doped layers. The gradation of the intrinsic layer is effected such that the open circuit voltage and/or the fill factor of the one or plural solar cell structure is enhanced.
Tunable cavity resonator including a plurality of MEMS beams
Peroulis, Dimitrios; Fruehling, Adam; Small, Joshua Azariah; Liu, Xiaoguang; Irshad, Wasim; Arif, Muhammad Shoaib
2015-10-20
A tunable cavity resonator includes a substrate, a cap structure, and a tuning assembly. The cap structure extends from the substrate, and at least one of the substrate and the cap structure defines a resonator cavity. The tuning assembly is positioned at least partially within the resonator cavity. The tuning assembly includes a plurality of fixed-fixed MEMS beams configured for controllable movement relative to the substrate between an activated position and a deactivated position in order to tune a resonant frequency of the tunable cavity resonator.
MULTI-SCALE MODELING AND APPROXIMATION ASSISTED OPTIMIZATION OF BARE TUBE HEAT EXCHANGERS
Bacellar, Daniel; Ling, Jiazhen; Aute, Vikrant; Radermacher, Reinhard; Abdelaziz, Omar
2014-01-01
Air-to-refrigerant heat exchangers are very common in air-conditioning, heat pump and refrigeration applications. In these heat exchangers, there is a great benefit in terms of size, weight, refrigerant charge and heat transfer coefficient, by moving from conventional channel sizes (~ 9mm) to smaller channel sizes (< 5mm). This work investigates new designs for air-to-refrigerant heat exchangers with tube outer diameter ranging from 0.5 to 2.0mm. The goal of this research is to develop and optimize the design of these heat exchangers and compare their performance with existing state of the art designs. The air-side performance of various tube bundle configurations are analyzed using a Parallel Parameterized CFD (PPCFD) technique. PPCFD allows for fast-parametric CFD analyses of various geometries with topology change. Approximation techniques drastically reduce the number of CFD evaluations required during optimization. Maximum Entropy Design method is used for sampling and Kriging method is used for metamodeling. Metamodels are developed for the air-side heat transfer coefficients and pressure drop as a function of tube-bundle dimensions and air velocity. The metamodels are then integrated with an air-to-refrigerant heat exchanger design code. This integration allows a multi-scale analysis of air-side performance heat exchangers including air-to-refrigerant heat transfer and phase change. Overall optimization is carried out using a multi-objective genetic algorithm. The optimal designs found can exhibit 50 percent size reduction, 75 percent decrease in air side pressure drop and doubled air heat transfer coefficients compared to a high performance compact micro channel heat exchanger with same capacity and flow rates.
Second Argonne theory institute on differentiation of computational approximations of functions.
Bischof, C.H.; Eberhard, P.; Hovland, P.D.
1998-10-09
A Theory Institute on ''Differentiation of Computational Approximations to Functions'' was held at Argonne National Laboratory on May 18--20, 1998. The institute was organized by Christian Bischof and Paul Hovland of the Mathematics and Computer Science Division at Argonne National Laboratory. The Theory Institute brought together 38 researchers from the US, Great Britain, France, and Germany. Mathematicians, computer scientists, physicists, and engineers from diverse disciplines discussed advances in automatic differentiation (AD) theory and software and described benefits from applying AD methods in application areas. These areas include fluid mechanics, structural engineering, optimization, meteorology, and computational mathematics for the solution of ordinary differential equations (ODEs) or differential algebraic equations (DAEs). This meeting was the fourth workshop dedicated to automatic differentiation. Earlier meetings were the 1991 SIAM conference in Breckenridge, Colorado; the first Argonne Theory Institute on computational differentiation in 1993; and the 1996 SIAM conference in Santa Fe, New Mexico. AD methods can be used whenever gradient information or higher-order derivative information must be computed. The problem is defined by a computer program (without gradient information) that is able to compute numerical values of some output variables for a given set of input variables. As a result of applying AD methods to this computer program, a new computer program is generated automatically to compute the derivatives of the output variables with respect to the input variables. This at first glance, astonishing fact can be easily understood by viewing the program from a compiler angle. A complicated computational sequence is split into a sequence of simple operations. Then, to compute the gradients, the chain rule of differentiation is applied successively to this sequence completely automatically. The resultant gradients are accurate up to roundoff
Heng, Kevin; Mendonça, João M.; Lee, Jae-Min E-mail: joao.mendonca@csh.unibe.ch
2014-11-01
We present a comprehensive analytical study of radiative transfer using the method of moments and include the effects of non-isotropic scattering in the coherent limit. Within this unified formalism, we derive the governing equations and solutions describing two-stream radiative transfer (which approximates the passage of radiation as a pair of outgoing and incoming fluxes), flux-limited diffusion (which describes radiative transfer in the deep interior), and solutions for the temperature-pressure profiles. Generally, the problem is mathematically underdetermined unless a set of closures (Eddington coefficients) is specified. We demonstrate that the hemispheric (or hemi-isotropic) closure naturally derives from the radiative transfer equation if energy conservation is obeyed, while the Eddington closure produces spurious enhancements of both reflected light and thermal emission. We concoct recipes for implementing two-stream radiative transfer in stand-alone numerical calculations and general circulation models. We use our two-stream solutions to construct toy models of the runaway greenhouse effect. We present a new solution for temperature-pressure profiles with a non-constant optical opacity and elucidate the effects of non-isotropic scattering in the optical and infrared. We derive generalized expressions for the spherical and Bond albedos and the photon deposition depth. We demonstrate that the value of the optical depth corresponding to the photosphere is not always 2/3 (Milne's solution) and depends on a combination of stellar irradiation, internal heat, and the properties of scattering in both the optical and infrared. Finally, we derive generalized expressions for the total, net, outgoing, and incoming fluxes in the convective regime.
DOE Seeks to Invest Approximately $1.3 Billion to Commercialize CCS
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Technology | Department of Energy Approximately $1.3 Billion to Commercialize CCS Technology DOE Seeks to Invest Approximately $1.3 Billion to Commercialize CCS Technology June 24, 2008 - 2:15pm Addthis Funding Opportunity Announcement Solicits Applications for Restructured FutureGen Program WASHINGTON, DC - The U.S. Department of Energy (DOE) today issued a Funding Opportunity Announcement (FOA) to invest in multiple commercial-scale Integrated Gasification Combined Cycle (IGCC) or other
Pusa, M.; Leppaenen, J.
2012-07-01
The Chebyshev Rational Approximation Method (CRAM) has been recently introduced by the authors for solving the burnup equations with excellent results. This method has been shown to be capable of simultaneously solving an entire burnup system with thousands of nuclides both accurately and efficiently. The method was prompted by an analysis of the spectral properties of burnup matrices and it can be characterized as the best rational approximation on the negative real axis. The coefficients of the rational approximation are fixed and have been reported for various approximation orders. In addition to these coefficients, implementing the method only requires a linear solver. This paper describes an efficient method for solving the linear systems associated with the CRAM approximation. The introduced direct method is based on sparse Gaussian elimination where the sparsity pattern of the resulting upper triangular matrix is determined before the numerical elimination phase. The stability of the proposed Gaussian elimination method is discussed based on considering the numerical properties of burnup matrices. Suitable algorithms are presented for computing the symbolic factorization and numerical elimination in order to facilitate the implementation of CRAM and its adoption into routine use. The accuracy and efficiency of the described technique are demonstrated by computing the CRAM approximations for a large test case with over 1600 nuclides. (authors)
cDNA encoding a polypeptide including a hevein sequence
Raikhel, N.V.; Broekaert, W.F.; Namhai Chua; Kush, A.
1993-02-16
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1,018 nucleotides long and includes an open reading frame of 204 amino acids.
Information regarding previous INCITE awards including selected highlights
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
| U.S. DOE Office of Science (SC) Information regarding previous INCITE awards including selected highlights Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities User Facilities Accessing ASCR Facilities Innovative & Novel Computational Impact on Theory & Experiement (INCITE) ASCR Leadership Computing Challenge (ALCC) Industrial Users Computational Science Graduate Fellowship (CSGF) Research & Evaluation Prototypes (REP) Science Highlights Benefits of
[Article 1 of 7: Motivates and Includes the Consumer]
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
2 of 7: Research on the Characteristics of a Modern Grid by the NETL Modern Grid Strategy Team Accommodates All Generation and Storage Options Last month we presented the first Principal Characteristic of a Modern Grid, "Motivates and Includes the Consumer". This month we present a second characteristic, "Accommodates All Generation and Storage Options". This characteristic will fundamentally transition today's grid from a centralized model for generation to one that also has
[Article 1 of 7: Motivates and Includes the Consumer]
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Series on the Seven Principal Characteristics of the Modern Grid [Article 1 of 7: Motivates and Includes the Consumer] In October 2007, Ken Silverstein (Energy Central) wrote an editorial, "Empowering Consumers" that hit a strong, kindred chord with the DOE/National Energy Technology Laboratory (NETL) Modern Grid Strategy team. Through subsequent discussions with Ken and Bill Opalka, Editor- In-Chief, Topics Centers, we decided it would be informative to the industry if the Modern Grid
Evaporative cooler including one or more rotating cooler louvers
Gerlach, David W
2015-02-03
An evaporative cooler may include an evaporative cooler housing with a duct extending therethrough, a plurality of cooler louvers with respective porous evaporative cooler pads, and a working fluid source conduit. The cooler louvers are arranged within the duct and rotatably connected to the cooler housing along respective louver axes. The source conduit provides an evaporative cooler working fluid to the cooler pads during at least one mode of operation.
Conversion of geothermal waste to commercial products including silica
Premuzic, Eugene T.; Lin, Mow S.
2003-01-01
A process for the treatment of geothermal residue includes contacting the pigmented amorphous silica-containing component with a depigmenting reagent one or more times to depigment the silica and produce a mixture containing depigmented amorphous silica and depigmenting reagent containing pigment material; separating the depigmented amorphous silica and from the depigmenting reagent to yield depigmented amorphous silica. Before or after the depigmenting contacting, the geothermal residue or depigmented silica can be treated with a metal solubilizing agent to produce another mixture containing pigmented or unpigmented amorphous silica-containing component and a solubilized metal-containing component; separating these components from each other to produce an amorphous silica product substantially devoid of metals and at least partially devoid of pigment. The amorphous silica product can be neutralized and thereafter dried at a temperature from about 25.degree. C. to 300.degree. C. The morphology of the silica product can be varied through the process conditions including sequence contacting steps, pH of depigmenting reagent, neutralization and drying conditions to tailor the amorphous silica for commercial use in products including filler for paint, paper, rubber and polymers, and chromatographic material.
Electrolytes including fluorinated solvents for use in electrochemical cells
Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan
2015-07-07
Provided are electrochemical cells and electrolytes used to build such cells. The electrolytes include ion-supplying salts and fluorinated solvents capable of maintaining single phase solutions with the salts at between about -30.degree. C. to about 80.degree. C. The fluorinated solvents, such as fluorinated carbonates, fluorinated esters, and fluorinated esters, are less flammable than their non-fluorinated counterparts and increase safety characteristics of cells containing these solvents. The amount of fluorinated solvents in electrolytes may be between about 30% and 80% by weight not accounting weight of the salts. Fluorinated salts, such as fluoroalkyl-substituted LiPF.sub.6, fluoroalkyl-substituted LiBF.sub.4 salts, linear and cyclic imide salts as well as methide salts including fluorinated alkyl groups, may be used due to their solubility in the fluorinated solvents. In some embodiments, the electrolyte may also include a flame retardant, such as a phosphazene or, more specifically, a cyclic phosphazene and/or one or more ionic liquids.
Multi-processor including data flow accelerator module
Davidson, George S.; Pierce, Paul E.
1990-01-01
An accelerator module for a data flow computer includes an intelligent memory. The module is added to a multiprocessor arrangement and uses a shared tagged memory architecture in the data flow computer. The intelligent memory module assigns locations for holding data values in correspondence with arcs leading to a node in a data dependency graph. Each primitive computation is associated with a corresponding memory cell, including a number of slots for operands needed to execute a primitive computation, a primitive identifying pointer, and linking slots for distributing the result of the cell computation to other cells requiring that result as an operand. Circuitry is provided for utilizing tag bits to determine automatically when all operands required by a processor are available and for scheduling the primitive for execution in a queue. Each memory cell of the module may be associated with any of the primitives, and the particular primitive to be executed by the processor associated with the cell is identified by providing an index, such as the cell number for the primitive, to the primitive lookup table of starting addresses. The module thus serves to perform functions previously performed by a number of sections of data flow architectures and coexists with conventional shared memory therein. A multiprocessing system including the module operates in a hybrid mode, wherein the same processing modules are used to perform some processing in a sequential mode, under immediate control of an operating system, while performing other processing in a data flow mode.
Rogers, J.; Porter, K.
2012-03-01
This paper updates previous work that describes time period-based and other approximation methods for estimating the capacity value of wind power and extends it to include solar power. The paper summarizes various methods presented in utility integrated resource plans, regional transmission organization methodologies, regional stakeholder initiatives, regulatory proceedings, and academic and industry studies. Time period-based approximation methods typically measure the contribution of a wind or solar plant at the time of system peak - sometimes over a period of months or the average of multiple years.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Isotalo, Aarno E.; Wieselquist, William A.
2015-05-15
A method for including external feed with polynomial time dependence in depletion calculations with the Chebyshev Rational Approximation Method (CRAM) is presented and the implementation of CRAM to the ORIGEN module of the SCALE suite is described. In addition to being able to handle time-dependent feed rates, the new solver also adds the capability to perform adjoint calculations. Results obtained with the new CRAM solver and the original depletion solver of ORIGEN are compared to high precision reference calculations, which shows the new solver to be orders of magnitude more accurate. Lastly, in most cases, the new solver is upmore » to several times faster due to not requiring similar substepping as the original one.« less
What To Include In The Whistleblower Complaint? | National Nuclear Security
National Nuclear Security Administration (NNSA)
Administration | (NNSA) To Include In The Whistleblower Complaint? Your complaint does not need to be in any specific form but must be signed by you and contain the following: A statement specifically describing 1. The alleged retaliation taken against you and 2. The disclosure, participation, or refusal that you believe gave rise to the retaliation; A statement that you are not currently pursuing a remedy under State or other applicable law, as described in Sec. 708.15 of this subpart; A
NREL: Technology Deployment - Cities-LEAP Energy Profile Tool Includes
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Energy Data on More than 23,400 U.S. Cities Cities-LEAP Energy Profile Tool Includes Energy Data on More than 23,400 U.S. Cities News NREL Report Examines Energy Use in Cities and Proposes Next Steps for Energy Innovation Publications Citi-Level Energy Decision Making: Data Use in Energy Planning, Implementation, and Evaluation in U.S. Cities Sponsors DOE's Energy Office of Energy Efficiency and Renewable Energy Policy and Analysis Office Related Stories Hawaii's First Net-Zero Energy
Composite armor, armor system and vehicle including armor system
Chu, Henry S.; Jones, Warren F.; Lacy, Jeffrey M.; Thinnes, Gary L.
2013-01-01
Composite armor panels are disclosed. Each panel comprises a plurality of functional layers comprising at least an outermost layer, an intermediate layer and a base layer. An armor system incorporating armor panels is also disclosed. Armor panels are mounted on carriages movably secured to adjacent rails of a rail system. Each panel may be moved on its associated rail and into partially overlapping relationship with another panel on an adjacent rail for protection against incoming ordnance from various directions. The rail system may be configured as at least a part of a ring, and be disposed about a hatch on a vehicle. Vehicles including an armor system are also disclosed.
cDNA encoding a polypeptide including a hevein sequence
Raikhel, Natasha V.; Broekaert, Willem F.; Chua, Nam-Hai; Kush, Anil
1993-02-16
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a pu GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon.
A coke oven model including thermal decomposition kinetics of tar
Munekane, Fuminori; Yamaguchi, Yukio; Tanioka, Seiichi
1997-12-31
A new one-dimensional coke oven model has been developed for simulating the amount and the characteristics of by-products such as tar and gas as well as coke. This model consists of both heat transfer and chemical kinetics including thermal decomposition of coal and tar. The chemical kinetics constants are obtained by estimation based on the results of experiments conducted to investigate the thermal decomposition of both coal and tar. The calculation results using the new model are in good agreement with experimental ones.
Composite material including nanocrystals and methods of making
Bawendi, Moungi G.; Sundar, Vikram C.
2008-02-05
Temperature-sensing compositions can include an inorganic material, such as a semiconductor nanocrystal. The nanocrystal can be a dependable and accurate indicator of temperature. The intensity of emission of the nanocrystal varies with temperature and can be highly sensitive to surface temperature. The nanocrystals can be processed with a binder to form a matrix, which can be varied by altering the chemical nature of the surface of the nanocrystal. A nanocrystal with a compatibilizing outer layer can be incorporated into a coating formulation and retain its temperature sensitive emissive properties
Composite material including nanocrystals and methods of making
Bawendi, Moungi G.; Sundar, Vikram C.
2010-04-06
Temperature-sensing compositions can include an inorganic material, such as a semiconductor nanocrystal. The nanocrystal can be a dependable and accurate indicator of temperature. The intensity of emission of the nanocrystal varies with temperature and can be highly sensitive to surface temperature. The nanocrystals can be processed with a binder to form a matrix, which can be varied by altering the chemical nature of the surface of the nanocrystal. A nanocrystal with a compatibilizing outer layer can be incorporated into a coating formulation and retain its temperature sensitive emissive properties.
Community Assessment Tool for Public Health Emergencies Including Pandemic Influenza
ORAU's Oak Ridge Institute for Science Education
2011-04-14
The Community Assessment Tool (CAT) for Public Health Emergencies Including Pandemic Influenza (hereafter referred to as the CAT) was developed as a result of feedback received from several communities. These communities participated in workshops focused on influenza pandemic planning and response. The 2008 through 2011 workshops were sponsored by the Centers for Disease Control and Prevention (CDC). Feedback during those workshops indicated the need for a tool that a community can use to assess its readiness for a disaster - readiness from a total healthcare perspective, not just hospitals, but the whole healthcare system. The CAT intends to do just that - help strengthen existing preparedness plans by allowing the healthcare system and other agencies to work together during an influenza pandemic. It helps reveal each core agency partners (sectors) capabilities and resources, and highlights cases of the same vendors being used for resource supplies (e.g., personal protective equipment [PPE] and oxygen) by the partners (e.g., public health departments, clinics, or hospitals). The CAT also addresses gaps in the community's capabilities or potential shortages in resources. This tool has been reviewed by a variety of key subject matter experts from federal, state, and local agencies and organizations. It also has been piloted with various communities that consist of different population sizes, to include large urban to small rural communities.
Brett, Tobias Galla, Tobias
2014-03-28
We present a heuristic derivation of Gaussian approximations for stochastic chemical reaction systems with distributed delay. In particular, we derive the corresponding chemical Langevin equation. Due to the non-Markovian character of the underlying dynamics, these equations are integro-differential equations, and the noise in the Gaussian approximation is coloured. Following on from the chemical Langevin equation, a further reduction leads to the linear-noise approximation. We apply the formalism to a delay variant of the celebrated Brusselator model, and show how it can be used to characterise noise-driven quasi-cycles, as well as noise-triggered spiking. We find surprisingly intricate dependence of the typical frequency of quasi-cycles on the delay period.
Jin, Jinshuang; Li, Jun; Liu, Yu; Li, Xin-Qi; Yan, YiJing
2014-06-28
Beyond the second-order Born approximation, we propose an improved master equation approach to quantum transport under self-consistent Born approximation. The basic idea is to replace the free Green's function in the tunneling self-energy diagram by an effective reduced propagator under the Born approximation. This simple modification has remarkable consequences. It not only recovers the exact results for quantum transport through noninteracting systems under arbitrary voltages, but also predicts the challenging nonequilibrium Kondo effect. Compared to the nonequilibrium Green's function technique that formulates the calculation of specific correlation functions, the master equation approach contains richer dynamical information to allow more efficient studies for such as the shot noise and full counting statistics.
Relativistic equation of state at subnuclear densities in the Thomas-Fermi approximation
Zhang, Z. W.; Shen, H., E-mail: shennankai@gmail.com [School of Physics, Nankai University, Tianjin 300071 (China)
2014-06-20
We study the non-uniform nuclear matter using the self-consistent Thomas-Fermi approximation with a relativistic mean-field model. The non-uniform matter is assumed to be composed of a lattice of heavy nuclei surrounded by dripped nucleons. At each temperature T, proton fraction Y{sub p} , and baryon mass density ? {sub B}, we determine the thermodynamically favored state by minimizing the free energy with respect to the radius of the Wigner-Seitz cell, while the nucleon distribution in the cell can be determined self-consistently in the Thomas-Fermi approximation. A detailed comparison is made between the present results and previous calculations in the Thomas-Fermi approximation with a parameterized nucleon distribution that has been adopted in the widely used Shen equation of state.
Hydraulic engine valve actuation system including independent feedback control
Marriott, Craig D
2013-06-04
A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.
Recent progress and advances in iterative software (including parallel aspects)
Carey, G.; Young, D.M.; Kincaid, D.
1994-12-31
The purpose of the workshop is to provide a forum for discussion of the current state of iterative software packages. Of particular interest is software for large scale engineering and scientific applications, especially for distributed parallel systems. However, the authors will also review the state of software development for conventional architectures. This workshop will complement the other proposed workshops on iterative BLAS kernels and applications. The format for the workshop is as follows: To provide some structure, there will be brief presentations, each of less than five minutes duration and dealing with specific facets of the subject. These will be designed to focus the discussion and to stimulate an exchange with the participants. Issues to be covered include: The evolution of iterative packages, current state of the art, the parallel computing challenge, applications viewpoint, standards, and future directions and open problems.
Actuator assembly including a single axis of rotation locking member
Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.
2009-12-08
An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.
Fuel cell repeater unit including frame and separator plate
Yamanis, Jean; Hawkes, Justin R; Chiapetta, Jr., Louis; Bird, Connie E; Sun, Ellen Y; Croteau, Paul F
2013-11-05
An example fuel cell repeater includes a separator plate and a frame establishing at least a portion of a flow path that is operative to communicate fuel to or from at least one fuel cell held by the frame relative to the separator plate. The flow path has a perimeter and any fuel within the perimeter flow across the at least one fuel cell in a first direction. The separator plate, the frame, or both establish at least one conduit positioned outside the flow path perimeter. The conduit is outside of the flow path perimeter and is configured to direct flow in a second, different direction. The conduit is fluidly coupled with the flow path.
Electra-optical device including a nitrogen containing electrolyte
Bates, J.B.; Dudney, N.J.; Gruzalski, G.R.; Luck, C.F.
1995-10-03
Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode. Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between {minus}15 C and 150 C.
Electra-optical device including a nitrogen containing electrolyte
Bates, John B.; Dudney, Nancy J.; Gruzalski, Greg R.; Luck, Christopher F.
1995-01-01
Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between -15.degree. C. and 150.degree. C.
Dye laser amplifier including a specifically designed diffuser assembly
Davin, James; Johnston, James P.
1992-01-01
A large (high flow rate) dye laser amplifier in which a continuous replened supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a relatively high flow rate and a specifically designed diffuser assembly for slowing down the flow of dye while, at the same time, assuring that as the dye stream flows through the diffuser assembly it does so in a stable manner.
Copper laser modulator driving assembly including a magnetic compression laser
Cook, Edward G.; Birx, Daniel L.; Ball, Don G.
1994-01-01
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.
Nijmegen soft-core potential including two-meson exchange
Stoks, V.G.J.; Rijken, T.A.
1995-05-10
We report on the progress of the construction of the extended soft-core (ESC) Nijmegen potential. Next to the standard one-boson-exchange parts, the model includes the pion-meson-exchange potentials due to the parallel and crossed-box diagrams, as well as the one-pair and two-pair diagrams, vertices for which can be identified with similar interactions appearing in chiral-symmetric Lagrangians. Although the ESC potential is still under construction, it already gives an excellent description of all {ital NN} scattering data below 350 MeV with {chi}{sup 2}/datum=1.3. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.
Pulse transmission transmitter including a higher order time derivate filter
Dress, Jr., William B.; Smith, Stephen F.
2003-09-23
Systems and methods for pulse-transmission low-power communication modes are disclosed. A pulse transmission transmitter includes: a clock; a pseudorandom polynomial generator coupled to the clock, the pseudorandom polynomial generator having a polynomial load input; an exclusive-OR gate coupled to the pseudorandom polynomial generator, the exclusive-OR gate having a serial data input; a programmable delay circuit coupled to both the clock and the exclusive-OR gate; a pulse generator coupled to the programmable delay circuit; and a higher order time derivative filter coupled to the pulse generator. The systems and methods significantly reduce lower-frequency emissions from pulse transmission spread-spectrum communication modes, which reduces potentially harmful interference to existing radio frequency services and users and also simultaneously permit transmission of multiple data bits by utilizing specific pulse shapes.
Approximate local magnetic-to-electric surface operators for time-harmonic Maxwell's equations
El Bouajaji, M.
2014-12-15
The aim of this paper is to propose new local and accurate approximate magnetic-to-electric surface boundary operators for the three-dimensional time-harmonic Maxwell's equations. After their construction where their accuracy is improved through a regularization process, a localization of these operators and a full finite element approximation is introduced. Next, their numerical efficiency and accuracy is investigated in detail for different scatterers when these operators are used in the extreme situation of On-Surface Radiation Conditions methods.
On the approximations of the distribution function of fusion alpha particles
Bilato, R. Brambilla, M.; Poli, E.
2014-10-15
The solution of the drift-kinetic equation for fusion-born alpha particles is derived in the limit of dominant parallel streaming, and it is related to the usual slowing-down distribution function. The typical approximations of the fast tail of fusion-born alpha particles are briefly compared and discussed. In particular, approximating the distribution function of fast-alpha particles with an equivalent Maxwellian is inaccurate to describe absorption of radio-frequency waves in the ion-cyclotron range of frequencies.
Liu, Fang; Lin, Lin; Vigil-Fowler, Derek; Lischner, Johannes; Kemper, Alexander F.; Sharifzadeh, Sahar; Jornada, Felipe H. da; Deslippe, Jack; Yang, Chao; and others
2015-04-01
We present a numerical integration scheme for evaluating the convolution of a Green's function with a screened Coulomb potential on the real axis in the GW approximation of the self energy. Our scheme takes the zero broadening limit in Green's function first, replaces the numerator of the integrand with a piecewise polynomial approximation, and performs principal value integration on subintervals analytically. We give the error bound of our numerical integration scheme and show by numerical examples that it is more reliable and accurate than the standard quadrature rules such as the composite trapezoidal rule. We also discuss the benefit of using different self energy expressions to perform the numerical convolution at different frequencies.
C -parameter distribution at N 3 LL ' including power corrections
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Hoang, André H.; Kolodrubetz, Daniel W.; Mateu, Vicent; Stewart, Iain W.
2015-05-15
We compute the e⁺e⁻ C-parameter distribution using the soft-collinear effective theory with a resummation to next-to-next-to-next-to-leading-log prime accuracy of the most singular partonic terms. This includes the known fixed-order QCD results up to O(α3s), a numerical determination of the two-loop nonlogarithmic term of the soft function, and all logarithmic terms in the jet and soft functions up to three loops. Our result holds for C in the peak, tail, and far tail regions. Additionally, we treat hadronization effects using a field theoretic nonperturbative soft function, with moments Ωn. To eliminate an O(ΛQCD) renormalon ambiguity in the soft function, we switchmore » from the MS¯ to a short distance “Rgap” scheme to define the leading power correction parameter Ω1. We show how to simultaneously account for running effects in Ω1 due to renormalon subtractions and hadron-mass effects, enabling power correction universality between C-parameter and thrust to be tested in our setup. We discuss in detail the impact of resummation and renormalon subtractions on the convergence. In the relevant fit region for αs(mZ) and Ω1, the perturbative uncertainty in our cross section is ≅ 2.5% at Q=mZ.« less
cDNA encoding a polypeptide including a hevein sequence
Raikhel, N.V.; Broekaert, W.F.; Chua, N.H.; Kush, A.
1999-05-04
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74--79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli. 12 figs.
cDNA encoding a polypeptide including a hevein sequence
Raikhel, Natasha V.; Broekaert, Willem F.; Chua, Nam-Hai; Kush, Anil
1999-05-04
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.
CDNA encoding a polypeptide including a hevein sequence
Raikhel, Natasha V.; Broekaert, Willem F.; Chua, Nam-Hai; Kush, Anil
1995-03-21
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.
cDNA encoding a polypeptide including a hevein sequence
Raikhel, N.V.; Broekaert, W.F.; Chua, N.H.; Kush, A.
1995-03-21
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1,018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74--79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli. 11 figures.
Interim performance criteria for photovoltaic energy systems. [Glossary included
DeBlasio, R.; Forman, S.; Hogan, S.; Nuss, G.; Post, H.; Ross, R.; Schafft, H.
1980-12-01
This document is a response to the Photovoltaic Research, Development, and Demonstration Act of 1978 (P.L. 95-590) which required the generation of performance criteria for photovoltaic energy systems. Since the document is evolutionary and will be updated, the term interim is used. More than 50 experts in the photovoltaic field have contributed in the writing and review of the 179 performance criteria listed in this document. The performance criteria address characteristics of present-day photovoltaic systems that are of interest to manufacturers, government agencies, purchasers, and all others interested in various aspects of photovoltaic system performance and safety. The performance criteria apply to the system as a whole and to its possible subsystems: array, power conditioning, monitor and control, storage, cabling, and power distribution. They are further categorized according to the following performance attributes: electrical, thermal, mechanical/structural, safety, durability/reliability, installation/operation/maintenance, and building/site. Each criterion contains a statement of expected performance (nonprescriptive), a method of evaluation, and a commentary with further information or justification. Over 50 references for background information are also given. A glossary with definitions relevant to photovoltaic systems and a section on test methods are presented in the appendices. Twenty test methods are included to measure performance characteristics of the subsystem elements. These test methods and other parts of the document will be expanded or revised as future experience and needs dictate.
Hydrogen atom excitation in intense attosecond laser field: Gauge dependence of dipole approximation
Aldarmaa, Ch. E-mail: l-xemee@yahoo.com; Khenmedekh, L. E-mail: l-xemee@yahoo.com; Lkhagva, O.
2014-03-24
It is assumed that, the atomic excitations probability can be calculated using first order perturbation theory and dipole approximations. The validity of the dipole approximations had been examined by comparing the results with the results obtained by exact calculations within the first order perturbation theory[2]. Figure 1 shows the time dependence of the transition probability in the dipole approximation. From these plots it is obvious that, the probabilities obtained in the length gauge are higher than that in the velocity gauge, in the interaction period (??/2
Smith, Kyle K. G.; Poulsen, Jens Aage Nyman, Gunnar; Rossky, Peter J.
2015-06-28
We develop two classes of quasi-classical dynamics that are shown to conserve the initial quantum ensemble when used in combination with the Feynman-Kleinert approximation of the density operator. These dynamics are used to improve the Feynman-Kleinert implementation of the classical Wigner approximation for the evaluation of quantum time correlation functions known as Feynman-Kleinert linearized path-integral. As shown, both classes of dynamics are able to recover the exact classical and high temperature limits of the quantum time correlation function, while a subset is able to recover the exact harmonic limit. A comparison of the approximate quantum time correlation functions obtained from both classes of dynamics is made with the exact results for the challenging model problems of the quartic and double-well potentials. It is found that these dynamics provide a great improvement over the classical Wigner approximation, in which purely classical dynamics are used. In a special case, our first method becomes identical to centroid molecular dynamics.
A New 2D-Transport, 1D-Diffusion Approximation of the Boltzmann Transport equation
Larsen, Edward
2013-06-17
The work performed in this project consisted of the derivation, implementation, and testing of a new, computationally advantageous approximation to the 3D Boltz- mann transport equation. The solution of the Boltzmann equation is the neutron flux in nuclear reactor cores and shields, but solving this equation is difficult and costly. The new “2D/1D” approximation takes advantage of a special geometric feature of typical 3D reactors to approximate the neutron transport physics in a specific (ax- ial) direction, but not in the other two (radial) directions. The resulting equation is much less expensive to solve computationally, and its solutions are expected to be sufficiently accurate for many practical problems. In this project we formulated the new equation, discretized it using standard methods, developed a stable itera- tion scheme for solving the equation, implemented the new numerical scheme in the MPACT code, and tested the method on several realistic problems. All the hoped- for features of this new approximation were seen. For large, difficult problems, the resulting 2D/1D solution is highly accurate, and is calculated about 100 times faster than a 3D discrete ordinates simulation.
Weber, J. W.; Bol, A. A. [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Sanden, M. C. M. van de [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Dutch Institute for Fundamental Energy Research (DIFFER), Nieuwegein (Netherlands)
2014-07-07
This work presents an improved thin film approximation to extract the optical conductivity from infrared transmittance in a simple yet accurate way. This approximation takes into account the incoherent reflections from the backside of the substrate. These reflections are shown to have a significant effect on the extracted optical conductivity and hence on derived parameters as carrier mobility and density. By excluding the backside reflections, the error for these parameters for typical chemical vapor deposited (CVD) graphene on a silicon substrate can be as high as 17% and 45% for the carrier mobility and density, respectively. For the mid- and near-infrared, the approximation can be simplified such that the real part of the optical conductivity is extracted without the need for a parameterization of the optical conductivity. This direct extraction is shown for Fourier transform infrared (FTIR) transmittance measurements of CVD graphene on silicon in the photon energy range of 3707000?cm{sup ?1}. From the real part of the optical conductivity, the carrier density, mobility, and number of graphene layers are determined but also residue, originating from the graphene transfer, is detected. FTIR transmittance analyzed with the improved thin film approximation is shown to be a non-invasive, easy, and accurate measurement and analysis method for assessing the quality of graphene and can be used for other 2-D materials.
Zhou, Zhennan
2014-09-01
In this paper, we approximate the semi-classical Schrdinger equation in the presence of electromagnetic field by the Hagedorn wave packets approach. By operator splitting, the Hamiltonian is divided into the modified part and the residual part. The modified Hamiltonian, which is the main new idea of this paper, is chosen by the fact that Hagedorn wave packets are localized both in space and momentum so that a crucial correction term is added to the truncated Hamiltonian, and is treated by evolving the parameters associated with the Hagedorn wave packets. The residual part is treated by a Galerkin approximation. We prove that, with the modified Hamiltonian only, the Hagedorn wave packets dynamics give the asymptotic solution with error O(?{sup 1/2}), where ? is the scaled Planck constant. We also prove that, the Galerkin approximation for the residual Hamiltonian can reduce the approximation error to O(?{sup k/2}), where k depends on the number of Hagedorn wave packets added to the dynamics. This approach is easy to implement, and can be naturally extended to the multidimensional cases. Unlike the high order Gaussian beam method, in which the non-constant cut-off function is necessary and some extra error is introduced, the Hagedorn wave packets approach gives a practical way to improve accuracy even when ? is not very small.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tang, J. Y.
2015-09-03
reverse Michaelis–Menten kinetics persistently under-predicts ∂ ln v / ∂ ln k2+ and ∂ ln v / ∂ ln [ E ]T, and persistently over-predicts ∂ ln v / ∂ ln k1+ and ∂ ln v / ∂ ln [ S ]T. In contrast, the Equilibrium Chemistry Approximation kinetics always gives consistent predictions of ∂ ln v / ∂ ln k2+, ∂ ln v / ∂ ln k1+, ∂ ln v / ∂ ln [ E ]T and ∂ ln v / ∂ ln [ S ]T. Since the Equilibrium Chemistry Approximation kinetics includes the advantages from both the Michaelis–Menten kinetics and the reverse Michaelis–Menten kinetics and it is applicable for almost the whole range of substrate and enzyme abundances, soil biogeochemical modelers therefore no longer need to choose when to use the Michaelis–Menten kinetics or the reverse Michaelis–Menten kinetics. I expect removing this choice ambiguity will make it easier to formulate more robust and consistent land biogeochemical models.« less