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1

Near-field enhancement of metal nano-particle based on the light focusing by the micro-parabolic mirror  

E-Print Network (OSTI)

Near-field enhancement of metal nano-particle based on the light focusing by the micro-parabolic mirror , , , , Abstract We propose to use a micro-parabolic mirror, in order to improve the near- parabolic mirror, the mirror-reflected light can be efficiently transformed into the near-field of the nano

Park, Namkyoo

2

Lighting Group: Sources and Ballasts: LED Task Light  

NLE Websites -- All DOE Office Websites (Extended Search)

light The goal of this project is to accelerate the use of energy efficient light emitting diode (LED) technology for general lighting applications by developing a task lamp...

3

Microphotonic parabolic light directors fabricated by two-photon lithography  

E-Print Network (OSTI)

light directors for producing collimated beams for applications in advanced solar cell and light-emitting diode designs. VC 2011 American Institute of Physics. [doi:10.1063/1.3648115] Planar micro- and nano

Heaton, Thomas H.

4

Reactor Pressure Vessel Task of Light Water Reactor Sustainability...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment Reactor Pressure...

5

Lighting and Sustained Performance: Modeling Data-Entry Task Performance  

Science Conference Proceedings (OSTI)

This report describes an experiment undertaken to determine the effect of different lighting and print conditions on the sustained performance of a repetitive, self-paced, data-entry task. This research led to the development of an empirical model of task performance, the Data-Entry Task Performance (DETP) model, which can be used to quantify the amount of work done on a data-entry task in a fixed time for changes in illuminance, print size, and luminance contrast.

2000-04-13T23:59:59.000Z

6

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Initial Assessment of Thermal Annealing Needs and Challenges Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Initial Assessment of Thermal Annealing Needs and Challenges The most life-limiting structural component in light-water reactors (LWR) is the reactor pressure vessel (RPV) because replacement of the RPV is not considered a viable option at this time. LWR licenses are now being extended from 40y to 60y by the U.S. Nuclear Regulatory Commission (NRC) with intentions to extend licenses to 80y and beyond. The RPV materials exhibit varying degrees of sensitivity to irradiation-induced embrittlement (decreased toughness) , as shown in Fig. 1.1, and extending operation from

7

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment The reactor pressure vessel (RPV) in a light-water reactor (LWR) represents the first line of defense against a release of radiation in case of an accident. Thus, regulations, which govern the operation of commercial nuclear power plants, require conservative margins of fracture toughness, both during normal operation and under accident scenarios. In the unirradiated condition, the RPV has sufficient fracture toughness such that failure is implausible under any postulated condition, including

8

Nexant Parabolic Trough Solar Power Plant Systems Analysis; Task 3: Multiple Plants at a Common Location, 20 January 2005 - 31 December 2005  

DOE Green Energy (OSTI)

Subcontract report by Nexant, Inc., regarding a system analysis of multiple solar parabolic trough plants at a common location.

Kelly, B.

2006-07-01T23:59:59.000Z

9

New and Underutilized Technology: Low Ambient/Task Lighting | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Low Ambient/Task Lighting Low Ambient/Task Lighting New and Underutilized Technology: Low Ambient/Task Lighting October 4, 2013 - 4:51pm Addthis The following information outlines key deployment considerations for low ambient/task lighting within the Federal sector. Benefits The low ambient/task lighting strategy improves the visual environment by adding controllable task fixtures that provide light directly where needed for a given task, while reducing the overhead (ambient) light level. Occupancy sensors can also be incorporated into the system. Application Low ambient/task lighting is applicable in most building categories. Key Factors for Deployment Low ambient/task lighting is suitable for most office spaces, including both cubicle and private office space environments, and should be

10

Nexant Parabolic Trough Solar Power Plant Systems Analysis; Task 1: Preferred Plant Size, 20 January 2005 - 31 December 2005  

DOE Green Energy (OSTI)

The Rankine cycles for commercial parabolic trough solar projects range in capacity from 13.5 MWe at the Solar Electric Generating Station I (SEGS I) plant, to a maximum of 89 MWe at the SEGS VIII/IX plants. The series of SEGS projects showed a consistent reduction in the levelized energy cost due to a combination of improvements in collector field technology and economies of scale in both the Rankine cycle and the operation and maintenance costs. Nonetheless, the question of the optimum Rankine cycle capacity remains an open issue. The capacities of the SEGS VIII/IX plants were limited by Federal Energy Regulatory Commission and Public Utility Regulatory Policy Act requirements to a maximum net output of 80 MWe. Further improvements in the Rankine cycle efficiency, and economies of scale in both the capital and the operating cost, should be available at larger plant sizes. An analysis was conducted to determine the effect of Rankine cycle capacities greater than 80 MWe on the levelized energy cost. The study was conducted through the following steps: (1) Three gross cycle capacities of 88 MWe, 165 MWe, and 220 MWe were selected. (2) Three Rankine cycle models were developed using the GateCycle program. The models were based on single reheat turbine cycles, with main steam conditions of 1,450 lb{sub f}/in{sup 2} and 703 F, and reheat steam conditions of 239 lb{sub f}/in{sup 2} and 703 F. The feedwater heater system consisted of 5 closed heaters and 1 open deaerating heater. The design condenser pressure was 2.5 in. HgA. (3) The optimization function within Excelergy was used to determine the preferred solar multiple for each plant. Two cases were considered for each plant: (a) a solar-only project without thermal storage, and (b) a solar-fossil hybrid project, with 3 hours of thermal storage and a heat transport fluid heater fired by natural gas. (4) For each of the 6 cases, collector field geometries, heat transport fluid pressure losses, and heat transport pump power requirements were calculated with a field piping optimization model. (5) Annual electric energy outputs, capital costs, and annual operating costs were calculated for each case using the default methods within Excelergy, from which estimates of the levelized energy costs were developed. The plant with the lowest energy cost was considered the optimum.

Kelly, B.

2006-07-01T23:59:59.000Z

11

Nexant Parabolic Trough Solar Power Plant Systems Analysis; Task 2: Comparison of Wet and Dry Rankine Cycle Heat Rejection, 20 January 2005 - 31 December 2005  

DOE Green Energy (OSTI)

Subcontract report by Nexant, Inc., regarding a system analysis comparing solar parabolic trough plants with wet and dry rankine cycle heat rejection.

Kelly, B.

2006-07-01T23:59:59.000Z

12

Task-ambient office lighting. Final report, October 1979-June 1980  

SciTech Connect

A method is discussed for converting uniform office lighting systems to task-ambient lighting systems. The method requires only the use of a light meter and a mirror. A correlation between the method and equivalent sphere illumination is shown. Several examples of offices converted from uniform lighting to task-ambient lighting are discussed.

Pierpoint, W.

1980-09-01T23:59:59.000Z

13

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Assessment of High Value Surveillance Materials Assessment of High Value Surveillance Materials Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Assessment of High Value Surveillance Materials The reactor pressure vessel (RPV) in a light-water reactor (LWR) represents the first line of defense against a release of radiation in case of an accident. Thus, regulations that govern the operation of commercial nuclear power plants require conservative margins of fracture toughness, both during normal operation and under accident scenarios. In the unirradiated condition, the RPV has sufficient fracture toughness such that failure is implausible under any postulated condition, including pressurized thermal shock (PTS) in pressurized water reactors (PWR). In the irradiated condition, however, the fracture toughness of the RPV may be severely

14

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Initial Assessment of Thermal Annealing Needs and Challenges Initial Assessment of Thermal Annealing Needs and Challenges Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Initial Assessment of Thermal Annealing Needs and Challenges The most life-limiting structural component in light-water reactors (LWR) is the reactor pressure vessel (RPV) because replacement of the RPV is not considered a viable option at this time. LWR licenses are now being extended from 40y to 60y by the U.S. Nuclear Regulatory Commission (NRC) with intentions to extend licenses to 80y and beyond. The RPV materials exhibit varying degrees of sensitivity to irradiation-induced embrittlement (decreased toughness) , as shown in Fig. 1.1, and extending operation from 40y to 80y implies a doubling of the neutron exposure for the RPV. Thus,

15

Parabolic Scaling and Curvelets Beyond Parabolic Scaling  

E-Print Network (OSTI)

Parabolic Scaling and Curvelets Beyond Parabolic Scaling Cubic Scaling for Caustics and Tangential on Imaging Science Hart F. Smith Cubic Scaling for Caustics and Tangential Reflections #12;Parabolic Scaling and Curvelets Beyond Parabolic Scaling The Second Dyadic Decomposition Wave-Evolution of Curvelets Second Dyadic

Smith, Hart F.

16

Parabolic geometries BGG sequences  

E-Print Network (OSTI)

Parabolic geometries BGG sequences Prolongation procedures BGG Sequences and Geometric sequences and overdetermined systems #12;Parabolic geometries BGG sequences Prolongation procedures Parabolic geometries are a large class of differential geometric structures, which can be described

Drmota, Michael

17

Parabolic Quantum Cloak.  

E-Print Network (OSTI)

??It is shown that the parabolic quantum cloak can be theoretically design by using âtransformation design methodâ. We discuss the possibility to build a parabolic… (more)

Chang, Yu-Hsuan

2013-01-01T23:59:59.000Z

18

The parabolic Harnack inequality  

E-Print Network (OSTI)

The parabolic Harnack inequality on metric graphs Sebastian Haeseler 1. Basic definitions 2. Volume-doubling properties 3. Poincar´e inequalities 4. The parabolic Harnack inequality 5. Examples The parabolic Harnack parabolic Harnack inequality on metric graphs Sebastian Haeseler 1. Basic definitions 2. Volume

Novak, Erich

19

Parabolic Raynaud bundles  

E-Print Network (OSTI)

Let X be an irreducible smooth projective curve defined over complex numbers, S= {p_1, p_2,...,p_n} \\subset X$ a finite set of closed points and N > 1 a fixed integer. For any pair (r,d) in Z X Z/N, there exists a parabolic vector bundle R_{r,d,*} on X, with parabolic structure over S and all parabolic weights in Z/N, that has the following property: Take any parabolic vector bundle E_* of rank r on X whose parabolic points are contained in S, all the parabolic weights are in Z/N and the parabolic degree is d. Then E_* is parabolic semistable if and only if there is no nonzero parabolic homomorphism from R_{r,d,*} to E_*.

Biswas, Indranil

2007-01-01T23:59:59.000Z

20

Parabolic-like maps  

E-Print Network (OSTI)

In this paper we introduce the notion of parabolic-like mapping, which is an object similar to a polynomial-like mapping, but with a parabolic external class, i.e. an external map with a parabolic fixed point. We prove a straightening theorem for parabolic-like maps, which states that any parabolic-like map of degree 2 is hybrid conjugate to a member of the family Per_1(1), and this member is unique (up to holomorphic conjugacy) if the filled Julia set of the parabolic-like map is connected.

Lomonaco, Luciana Luna Anna

2011-01-01T23:59:59.000Z

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


21

Presenting parabolic subgroups  

E-Print Network (OSTI)

Consider a relatively hyperbolic group G. We prove that if G is finitely presented, so are its parabolic subgroups. Moreover, a presentation of the parabolic subgroups can be found algorithmically from a presentation of G, a solution of its word problem, and generating sets of the parabolic subgroups. We also give an algorithm that finds parabolic subgroups in a given recursively enumerable class of groups.

Dahmani, François

2010-01-01T23:59:59.000Z

22

PARABOLIC GEODESICS AS PARALLEL CURVES IN PARABOLIC GEOMETRIES  

E-Print Network (OSTI)

PARABOLIC GEODESICS AS PARALLEL CURVES IN PARABOLIC GEOMETRIES MARC HERZLICH Abstract. We give a simple characterization of the parabolic geodesics introduced by Cap, Slovák and Zádník for all parabolic then show that parabolic geodesics can be characterized as the following data: a curve on the manifold

Paris-Sud XI, Université de

23

Parabolic flows on complex manifolds  

E-Print Network (OSTI)

Chapter 2 Convergence of the parabolic complex Monge-Amp`ere65] Streets, J. , Tian, G. A parabolic flow of pluriclosedGill, M. Convergence of the parabolic complex Monge-Amp` ere

Gill, Matthew Franklin

2012-01-01T23:59:59.000Z

24

Optimal control, parabolic equations, st  

E-Print Network (OSTI)

state constraints, for parabolic systems have been studied in Casas [20], ... troduced for deriving optimality conditionsfor parabolic problems with pure or mixed.

25

Parabolic flows on complex manifolds.  

E-Print Network (OSTI)

??We prove C ? convergence for suitably normalized solutions of the parabolic complex Monge-Ampčre equation on compact Hermitian manifolds. This provides a parabolic proof of… (more)

Gill, Matthew Franklin

2012-01-01T23:59:59.000Z

26

On parabolic Whittaker functions  

E-Print Network (OSTI)

We derive a Mellin-Barnes integral representation for solution to generalized (parabolic) quantum Toda lattice introduced in \\cite{GLO}, which presumably describes the $(S^1\\times U_N)$-equivariant Gromov-Witten invariants of Grassmann variety.

Sergey Oblezin

2010-11-18T23:59:59.000Z

27

On parabolic Whittaker functions  

E-Print Network (OSTI)

We derive a Mellin-Barnes integral representation for solution to generalized (parabolic) quantum Toda lattice introduced in \\cite{GLO}, which presumably describes the $(S^1\\times U_N)$-equivariant Gromov-Witten invariants of Grassmann variety.

Oblezin, Sergey

2010-01-01T23:59:59.000Z

28

LED Surgical Task Lighting Scoping Study: A Hospital Energy Alliance Project  

SciTech Connect

Tungsten-halogen (halogen) lamps have traditionally been used to light surgical tasks in hospitals, even though they are in many respects ill-suited to the application due to the large percentage of radiant energy outside the visible spectrum and issues with color rendering/quality. Light-emitting diode (LED) technology offers potential for adjustable color and improved color rendition/quality, while simultaneously reducing side-effects from non-visible radiant energy. It also has the potential for significant energy savings, although this is a fairly narrow application in the larger commercial building energy use sector. Based on analysis of available products and Hospital Energy Alliance member interest, it is recommended that a product specification and field measurement procedure be developed for implementation in demonstration projects.

Tuenge, Jason R.

2011-01-17T23:59:59.000Z

29

Properties of parabolic Sobolev and parabolic Besov spaces  

E-Print Network (OSTI)

In this paper, we characterize parabolic Besov and parabolic Sobolev spaces in ${\\bf R}^{n+1}$ and ${\\bf R}^{n+1}_T, \\,\\, T > 0$. We also, study the relation between parabolic Besov spaces in ${\\bf R}^{n}_T, \\,\\, T > 0$ and standard Besov space in $\\R$.

Chang, Tongkeun

2011-01-01T23:59:59.000Z

30

PARABOLIC EXHAUSTIONS AND ANALYTIC COVERINGS  

E-Print Network (OSTI)

PARABOLIC EXHAUSTIONS AND ANALYTIC COVERINGS Finnur L´arusson January 31, 1993 Abstract. Let be a parabolic exhaustion on a Stein manifold X such that is strictly plurisubharmonic at its zeros. The metric to be parabolic because its logarithm is plurisubharmonic and satisfies the so-called Monge-Amp`ere equation

Lárusson, Finnur

31

Parabolically connected subgroups  

SciTech Connect

All reductive spherical subgroups of the group SL(n) are found for which the intersections with every parabolic subgroup of SL(n) are connected. This condition guarantees that open equivariant embeddings of the corresponding homogeneous spaces into Moishezon spaces are algebraic. Bibliography: 6 titles.

Netai, Igor V [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2011-08-31T23:59:59.000Z

32

A compound parabolic concentrator  

SciTech Connect

A compound parabolic concentrator (CPC) for solar energy applications is presented in this work. A prototype was built and its thermal performance was determined. Operating temperatures of the order of 150 /sup 0/C with a reasonable efficiency can be attained by means of a fixed CPC.

Manrique, J.A.

1984-05-01T23:59:59.000Z

33

Parabolic submanifolds of rank two  

E-Print Network (OSTI)

The goal of this paper is to classify parametrically parabolic submanifolds in any codimension. First, we describe the ones that are ruled and show that they are the only parabolic submanifolds that admit an isometric immersion as a hypersurface. Then, we classify the nonruled ones by two different means. In fact, we provide the polar and bipolar parametrizations, each of which is associated to a parabolic surface and a function on the surface which satisfies a parabolic differential equation. To conclude, we describe the structure of the singular set of the nonruled parabolic submanifolds.

Dajczer, Marcos

2009-01-01T23:59:59.000Z

34

Parabolic k-ample bundles  

E-Print Network (OSTI)

We construct projectivization of a parabolic vector bundle and a tautological line bundle over it. It is shown that a parabolic vector bundle is ample if and only if the tautological line bundle is ample. This allows us to generalize the notion of a k-ample bundle, introduced by Sommese, to the context of parabolic bundles. A parabolic vector bundle $E_*$ is defined to be k-ample if the tautological line bundle ${\\mathcal O}_{{\\mathbb P}(E_*)}(1)$ is $k$--ample. We establish some properties of parabolic k-ample bundles.

Biswas, Indranil

2011-01-01T23:59:59.000Z

35

Session: Parabolic Troughs (Presentation)  

DOE Green Energy (OSTI)

The project description is R and D activities at NREL and Sandia aimed at lowering the delivered energy cost of parabolic trough collector systems and FOA awards to support industry in trought development. The primary objectives are: (1) support development of near-term parabolic trought technology for central station power generation; (2) support development of next-generation trought fields; and (3) support expansion of US trough industry. The major FY08 activities were: (1) improving reflector optics; (2) reducing receiver heat loss (including improved receiver coating and mitigating hydrogen accumulation); (3) measuring collector optical efficiency; (4) optimizing plant performance and reducing cost; (5) reducing plant water consumption; and (6) directly supporting industry needs, including FOA support.

Kutscher, C.

2008-04-01T23:59:59.000Z

36

Parabolic John-Nirenberg spaces  

E-Print Network (OSTI)

We introduce a parabolic version of John-Nirenberg space with exponent $p$ and show that it is contained in local weak-$L^p$ spaces.

Berkovits, Lauri

2011-01-01T23:59:59.000Z

37

CALCULATING THE PARABOLIC CHERN CHARACTER OF A LOCALLY ABELIAN PARABOLIC BUNDLE  

E-Print Network (OSTI)

CALCULATING THE PARABOLIC CHERN CHARACTER OF A LOCALLY ABELIAN PARABOLIC BUNDLE CHADI HASSAN TAHER Abstract. We calculate the parabolic Chern character of a bundle with locally abelian parabolic structure for the parabolic Chern character of a locally abelian parabolic bundle on (X, D) in terms of: --the Chern character

Paris-Sud XI, Université de

38

Orthogonal parabolic reflector systems  

SciTech Connect

A structure is described comprising: a reflecting surface which has an axis and is open at least at one axial end and in an axial section generally conforms to an axial section through a surface generated by rotating a portion of a parabolic curve about an axis perpendicular to the axis of the parabola defined by the curve; and an elongated source/sink which extends at least in the direction of the axis of the reflecting surface and is at least partly enveloped by the reflecting surface.

Cheng, D.Y.

1993-08-10T23:59:59.000Z

39

A Relation Between the Parabolic . . .  

E-Print Network (OSTI)

In this paper, we consider the weight i de Rham–Gauss–Manin bundles on a smooth variety arising from a smooth projective morphism f: XU ? ? U for i ? 0. We associate to each weight i de Rham bundle, a certain parabolic bundle on S and consider their parabolic Chern characters in the rational Chow groups, for a good compactification S of U. We show the triviality of the alternating sum of these parabolic bundles in the (positive degree) rational Chow groups. This removes the hypothesis of semistable reduction in the original result of this kind due to Esnault and Viehweg.

Jaya NN Iyer; Carlos T. Simpson

2006-01-01T23:59:59.000Z

40

Parabolic subgroups of Garside groups  

E-Print Network (OSTI)

A Garside monoid is a cancellative monoid with a finite lattice generating set; a Garside group is the group of fractions of a Garside monoid. The family of Garside groups contains the Artin-Tits groups of spherical type. We generalise the well-known notion of a parabolic subgroup of an Artin-Tits group into that of a parabolic subgroup of a Garside group. We also define the more general notion of a Garside subgroup of a Garside group, which is related to the notion of LCMhomomorphisms between Artin-Tits groups. We prove that most of the properties of parabolic subgroups extend to this subgroups.

Eddy Godelle

2008-01-01T23:59:59.000Z

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


41

KSTABILITY AND PARABOLIC STABILITY YANN ROLLIN  

E-Print Network (OSTI)

K­STABILITY AND PARABOLIC STABILITY YANN ROLLIN Abstract. Parabolic structures with rational that the three notions of parabolic polystability, K­polystability and existence of constant sca­ lar curvature K, we study iterated blowups of ruled surfaces encoded by a parabolic structure. Our main result, stated

Paris-Sud XI, Université de

42

STUDIA MATHEMATICA 193 (3) (2009) On the parabolic-elliptic limit of the doubly parabolic  

E-Print Network (OSTI)

STUDIA MATHEMATICA 193 (3) (2009) On the parabolic-elliptic limit of the doubly parabolic Keller, of solu- tions of the parabolic-parabolic Keller­Segel system in the plane to the corresponding solutions of the parabolic-elliptic model, as a physical parameter goes to zero. Our main tools are suitable space

Pujo-Menjouet, Laurent

43

On the parabolic-elliptic limit of the doubly parabolic KellerSegel system  

E-Print Network (OSTI)

On the parabolic-elliptic limit of the doubly parabolic Keller­Segel system modelling chemotaxis convergence results, in strong topologies, for so- lutions of the parabolic-parabolic Keller­Segel system in the plane, to the corresponding solutions of the parabolic-elliptic model, as a phys- ical parameter goes

Paris-Sud XI, Université de

44

MODULI SPACES OF PARABOLIC HIGGS BUNDLES AND PARABOLIC K(D) PAIRS OVER SMOOTH CURVES: I  

E-Print Network (OSTI)

MODULI SPACES OF PARABOLIC HIGGS BUNDLES AND PARABOLIC K(D) PAIRS OVER SMOOTH CURVES: I HANS U. BODEN AND K â?? OJI YOKOGAWA Abstract. This paper concerns the moduli spaces of rank two parabolic Higgs bundles and parabolic K(D) pairs over a smooth curve. Precisely which parabolic bundles occur in stable K

Boden, Hans U.

45

THE CHERN CHARACTER OF A PARABOLIC BUNDLE, AND A PARABOLIC COROLLARY OF REZNIKOV'S THEOREM  

E-Print Network (OSTI)

THE CHERN CHARACTER OF A PARABOLIC BUNDLE, AND A PARABOLIC COROLLARY OF REZNIKOV'S THEOREM JAYA NN character of a locally abelian parabolic bundle in terms of its constituent bundles. Several features and variants of parabolic structures are discussed. Parabolic bundles arising from logarithmic connections form

Iyer, Jaya N,

46

Courant Algebroids in Parabolic Geometry  

E-Print Network (OSTI)

Let $p$ be a Lie subalgebra of a semisimple Lie algebra $g$ and $(G,P)$ be the corresponding pair of connected Lie groups. A Cartan geometry of type $(G,P)$ associates to a smooth manifold $M$ a principal $P$-bundle and a Cartan connection, and a parabolic geometry is a Cartan geometry where $P$ is parabolic. We show that if $P$ is parabolic, the adjoint tractor bundle of a Cartan geometry, which is isomorphic to the Atiyah algebroid of the principal $P$-bundle, admits the structure of a (pre-)Courant algebroid, and we identify the topological obstruction to the bracket being a Courant bracket. For semisimple $G$, the Atiyah algebroid of the principal $P$-bundle associated to the Cartan geometry of $(G,P)$ admits a pre-Courant algebroid structure if and only if $P$ is parabolic.

Stuart Armstrong; Rongmin Lu

2011-12-29T23:59:59.000Z

47

Progress in parabolic dish technology  

DOE Green Energy (OSTI)

This report describes the current status of parabolic dish technology. Its purpose is to communicate the principal outcomes of DOE's parabolic dish technology RandD efforts carried out at the Solar Energy Research Institute; Sandia National Laboratory, Albuquerque; the Jet Propulsion Laboratory; and other DOE national laboratories. It is written for those in industry, academia, and government who have a special interest in solar thermal systems that use parabolic dishes as collectors. The evolution of parabolic technology is described, and examples of projects in operation and under construction are included. Solar thermal dish technology can supply either electric or thermal energy to various applications over a broad range of system sizes and temperatures. These solar energy systems will be available by the time this country needs additional electric generation capacity -- in the mid to late 1990s -- at costs competitive with other energy sources. 9 refs., 54 figs., 6 tabs.

Stine, W.B.

1989-06-01T23:59:59.000Z

48

The Parabolic-Trigonometric Functions  

E-Print Network (OSTI)

The parabolic functions are introduced in analogy to the circular and hyperbolic cases. We discuss the relevant properties, the geometrical interpretation and touch on possible generalizations and their link with the modular elliptic functions.

G. Dattoli; M. Migliorati; M. Quattromini; P. E. Ricci

2011-02-08T23:59:59.000Z

49

Federal technology alert. Parabolic-trough solar water heating  

DOE Green Energy (OSTI)

Parabolic-trough solar water heating is a well-proven renewable energy technology with considerable potential for application at Federal facilities. For the US, parabolic-trough water-heating systems are most cost effective in the Southwest where direct solar radiation is high. Jails, hospitals, barracks, and other facilities that consistently use large volumes of hot water are particularly good candidates, as are facilities with central plants for district heating. As with any renewable energy or energy efficiency technology requiring significant initial capital investment, the primary condition that will make a parabolic-trough system economically viable is if it is replacing expensive conventional water heating. In combination with absorption cooling systems, parabolic-trough collectors can also be used for air-conditioning. Industrial Solar Technology (IST) of Golden, Colorado, is the sole current manufacturer of parabolic-trough solar water heating systems. IST has an Indefinite Delivery/Indefinite Quantity (IDIQ) contract with the Federal Energy Management Program (FEMP) of the US Department of Energy (DOE) to finance and install parabolic-trough solar water heating on an Energy Savings Performance Contract (ESPC) basis for any Federal facility that requests it and for which it proves viable. For an ESPC project, the facility does not pay for design, capital equipment, or installation. Instead, it pays only for guaranteed energy savings. Preparing and implementing delivery or task orders against the IDIQ is much simpler than the standard procurement process. This Federal Technology Alert (FTA) of the New Technology Demonstration Program is one of a series of guides to renewable energy and new energy-efficient technologies.

NONE

1998-04-01T23:59:59.000Z

50

Shenandoah parabolic dish solar collector  

DOE Green Energy (OSTI)

The objectives of the Shenandoah, Georgia, Solar Total Energy System are to design, construct, test, and operate a solar energy system to obtain experience with large-scale hardware systems for future applications. This report describes the initial design and testing activities conducted to select and develop a collector that would serve the need of such a solar total energy system. The parabolic dish was selected as the collector most likely to maximize energy collection as required by this specific site. The fabrication, testing, and installation of the parabolic dish collector incorporating improvements identified during the development testing phase are described.

Kinoshita, G.S.

1985-01-01T23:59:59.000Z

51

SunShot Initiative: Parabolic Trough  

NLE Websites -- All DOE Office Websites (Extended Search)

development (R&D) in parabolic trough systems as one of four concentrating solar power (CSP) technologies aiming to meet the goals of the SunShot Initiative. Parabolic troughs,...

52

THE STRUCTURE OF TWO-PARABOLIC SPACE: PARABOLIC DUST AND ITERATION.  

E-Print Network (OSTI)

THE STRUCTURE OF TWO-PARABOLIC SPACE: PARABOLIC DUST AND ITERATION. JANE GILMAN Abstract. A non-elementary M¨obius group generated by two- parabolics is determined up to conjugation by one complex para] to obtain an additional struc- ture for the parameter space, which we term the two-parabolic space

Gilman, Jane

53

PARABOLIC SCHEMES FOR QUASI-LINEAR PARABOLIC AND HYPERBOLIC PDES VIA STOCHASTIC CALCULUS  

E-Print Network (OSTI)

PARABOLIC SCHEMES FOR QUASI-LINEAR PARABOLIC AND HYPERBOLIC PDES VIA STOCHASTIC CALCULUS SEBASTIEN of a unique global strong solution for the parabolic system. We show the existence of a unique local strong not use weak solution theory but recursive parabolic schemes studied via a stochastic approach

Paris-Sud XI, Université de

54

AN ABSTRACT APPROACH TO DOMAIN PERTURBATION FOR PARABOLIC EQUATIONS AND PARABOLIC  

E-Print Network (OSTI)

AN ABSTRACT APPROACH TO DOMAIN PERTURBATION FOR PARABOLIC EQUATIONS AND PARABOLIC VARIATIONAL Australia Abstract. We study the behaviour of solutions of linear non-autonomous parabolic equations subject of func- tion spaces for non-autonomous parabolic problems is equivalent to Mosco convergence of function

Sydney, University of

55

Lighting  

SciTech Connect

The lighting section of ASHRAE standard 90.1 is discussed. It applies to all new buildings except low-rise residential, while excluding specialty lighting applications such as signage, art exhibits, theatrical productions, medical and dental tasks, and others. In addition, lighting for indoor plant growth is excluded if designed to operate only between 10 p.m. and 6 a.m. Lighting allowances for the interior of a building are determined by the use of the system performance path unless the space functions are not fully known, such as during the initial stages of design or for speculative buildings. In such cases, the prescriptive path is available. Lighting allowances for the exterior of all buildings are determined by a table of unit power allowances. A new addition the exterior lighting procedure is the inclusion of facade lighting. However, it is no longer possible to trade-off power allotted for the exterior with the interior of a building or vice versa. A significant change is the new emphasis on lighting controls.

McKay, H.N. (Hayden McKay Lighting Design, New York, NY (US))

1990-02-01T23:59:59.000Z

56

Threshold results for semilinear parabolic systems  

E-Print Network (OSTI)

A threshold result was proved in this paper for semilinear parabolic system with pure power type nonlinearities

Xie, Qiuyi Dai Haiyang He Junhui

2010-01-01T23:59:59.000Z

57

Lighting in Residential and Commercial Buildings (1993 and 1995 Data)  

U.S. Energy Information Administration (EIA) Indexed Site

Types > 1995 CBECS Lighting Equipment Types > 1995 CBECS Lighting Equipment 1995 CBECS Lighting Equipment Profile Lighting Equipment - Type and Characteristics of Equipment Emits Found In Incandescent Incandescent Light Bulb Produces light by electrically heating a tungsten filament Includes energy-efficient incandescent bulbs, such as Reflector or R-Lamps (accent and task lighting), Parabolic Aluminized Reflector (PAR) lamps (flood and spot lighting), and Ellipsoidal Reflector (ER) lamps (recessed lighting) Highly inefficient because much of the energy is lost as heat 14-18 Lumens Per Watt (LPW) 14% of Lit Commercial Floorspace Standard Fluorescent Lighting with Magnetic Ballast Standard Fluorescent with Magnetic Ballast Produces light by passing electricity through mercury vapor, causing the fluorescent coating to glow or fluoresce

58

REGULARITY FOR A DOUBLY NONLINEAR PARABOLIC EQUATION  

E-Print Network (OSTI)

REGULARITY FOR A DOUBLY NONLINEAR PARABOLIC EQUATION JUHA KINNUNEN Abstract. This survey focuses on regularity results for certain degenerate doubly nonlinear parabolic equations in the case when the Lebesgue This note focuses on the regularity of nonnegative weak solutions to the doubly nonlinear parabolic equation

Kinnunen, Juha

59

Coupled Parabolic Equations for Wave Propagation  

E-Print Network (OSTI)

Coupled Parabolic Equations for Wave Propagation Kai Huang, Knut Solna and Hongkai Zhao #3; April 30, 2004 Abstract We develop an algorithm using two coupled parabolic equations for numerical simulation of wave propagation over long distances. The coupled parabolic equations are derived from a two

Zhao, Hongkai

60

The parabolic Mandelbrot set Pascale ROESCH  

E-Print Network (OSTI)

The parabolic Mandelbrot set Pascale ROESCH (joint work with C. L. PETERSEN, IMFUFA Roskilde) Institute of Mathematics of Toulouse 21 february 2011 Roesch P. (IMT) The parabolic Mandelbrot set 21 february 2011 1 / 94 #12;Consider a rational map of degree d 2 Roesch P. (IMT) The parabolic Mandelbrot

Roesch, Pascale

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61

Parabolic Molecules Philipp Grohs and Gitta Kutyniok  

E-Print Network (OSTI)

Parabolic Molecules Philipp Grohs and Gitta Kutyniok June 9, 2012 Abstract Anisotropic decompositions using representation systems based on parabolic scaling such as curve- lets or shearlets have of the notion of parabolic molecules, we aim to provide a comprehensive framework which includes customarily

Kutyniok, Gitta

62

The near parabolic renormalization Inou and Shishikura  

E-Print Network (OSTI)

The near parabolic renormalization of Inou and Shishikura Arnaud Ch´eritat Institut de Math´ematiques de Toulouse Oberwolfach, April 2008 A. Ch´eritat (IMT) Near parabolic renormalization Oberwolfach, April 2008 1 / 19 #12;1 Renormalization in complex dynamics 2 The parabolic renormalization 3 Near

Chéritat, Arnaud

63

Degenerate Parabolic Stochastic Partial Differential Equations  

E-Print Network (OSTI)

Degenerate Parabolic Stochastic Partial Differential Equations Martina Hofmanov´a Abstract. We study the Cauchy problem for a scalar semilinear degenerate parabolic partial differential equation the notion of kinetic solution which is well suited for degenerate parabolic problems and supplies a good

Paris-Sud XI, Université de

64

Release Version Parabolic Dish Microphone System  

E-Print Network (OSTI)

Release Version Parabolic Dish Microphone System Prepared by: Zhixin Chen (Ph.D. Student), with the assistance of Robert C. Maher (Associate Professor) Montana State University A parabolic dish microphone is like a mirror telescope for sound. A parabolic reflector is used to collect and focus sound waves

Maher, Robert C.

65

Plane and parabolic solar panels  

E-Print Network (OSTI)

We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

Sales, J H O

2009-01-01T23:59:59.000Z

66

Plane and parabolic solar panels  

E-Print Network (OSTI)

We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

J. H. O. Sales; A. T. Suzuki

2009-05-14T23:59:59.000Z

67

Parabolic tapers for overmoded waveguides  

DOE Patents (OSTI)

A waveguide taper with a parabolic profile, in which the distance along the taper axis varies as the square of the tapered dimension, provides less mode conversion than equal length linear tapers and is easier to fabricate than other non-linear tapers.

Doane, J.L.

1983-11-25T23:59:59.000Z

68

NREL: TroughNet - Parabolic Trough Workshops  

NLE Websites -- All DOE Office Websites (Extended Search)

Parabolic Trough Workshops Parabolic Trough Workshops Here you'll find information about workshops and forums concerning parabolic trough technology and concentrating solar power. Also, see upcoming events on concentrating solar power. Past Workshops and Forums 2007 Parabolic Trough Technology Workshop March 8-9, 2007 Golden, CO 2007 Solar Power Tower, Dish Stirling and Linear Fresnel Technologies Workshop March 7, 2007 Golden, CO 2006 Parabolic Trough Technology Workshop February 14-16, 2006 Incline Village, NV 2004 Solar Thermal Electric International Project Development Forum July 13, 2004 Portland, OR 2003 Parabolic Trough Thermal Energy Storage Workshop February 20-21, 2003 Golden, CO 2001 Solar Energy Forum: The Power to Choose April 21-25, 2001 Washington, D.C. 2000 Parabolic Trough Technology Workshop

69

Parabolic concentrating collector: a tutorial  

DOE Green Energy (OSTI)

A tutorial overview of point-focusing parabolic collectors is presented. Optical and thermal characteristics of such collectors are discussed. Data representing typical achievable collector efficiencies are presented and the importance of balancing collector cost with concentrator quality is argued through the development of a figure of merit for the collector. The impact of receiver temperature on performance is assessed and the general observation made that temperatures much in excess of 1500 to 2000/sup 0/F can actually result in decreased performance. Various types of two-axis tracking collectors are described, including the standard parabolic deep dish, Cassegrainian and Fresnel, as well as two forms of fixed mirrors with articulating receivers. The present DOE program to develop these devices is briefly discussed, as are present and projected costs for these collectors. Pricing information is presented for the only known commercial design available on the open market.

Truscello, V.C.

1979-02-15T23:59:59.000Z

70

2 Technology Description: Solar Thermal Parabolic Trough Solar Thermal  

E-Print Network (OSTI)

Parabolic troughs track sun, concentrate incident light onto a centralized, tubular receiver that runs length of each trough – Thermal fluid circulates through all receivers in solar field – Thermal fluid brought to one or more centralized power production facilities – Heat transferred to a steam cycle, drives a steam turbine to generate power – Cooled thermal fluid is then recirculated th through h solar fi field ld – Wet cooling is common, dry cooling possible

Timothy J. Skone; Risks Of Implementation

2012-01-01T23:59:59.000Z

71

Parabolic systems and an underlying Lagrangian.  

E-Print Network (OSTI)

??In this thesis, we extend De Giorgi's interpolation method to a class of parabolic equations which are not gradient flows but possess an entropy functional… (more)

Yolcu, Türkay

2009-01-01T23:59:59.000Z

72

Parabolic Weingarten surfaces in hyperbolic space  

E-Print Network (OSTI)

A surface in hyperbolic space $\\h^3$ invariant by a group of parabolic isometries is called a parabolic surface. In this paper we investigate parabolic surfaces of $\\h^3$ that satisfy a linear Weingarten relation of the form $a\\kappa_1+b\\kappa_2=c$ or $aH+bK=c$, where $a,b,c\\in \\r$ and, as usual, $\\kappa_i$ are the principal curvatures, $H$ is the mean curvature and $K$ is de Gaussian curvature. We classify all parabolic linear Weingarten surfaces in hyperbolic space.

López, Rafael

2008-01-01T23:59:59.000Z

73

Parabolic equations without a minimum principle.  

E-Print Network (OSTI)

??In this thesis, we consider several parabolic equations for which the minimum principle fails. We first consider a two-point boundary value problem for a one… (more)

Pang, Huadong

2007-01-01T23:59:59.000Z

74

Performance of a parabolic trough solar collector.  

E-Print Network (OSTI)

??Parabolic trough solar collectors (PTSCs) constitute a proven source of thermal energy for industrial process heat and power generation, although their implementation has been strongly… (more)

Brooks, Michael John

2005-01-01T23:59:59.000Z

75

Bibliography Parabolic Geometries and Weyl connections Nearly invariant calculus (Wunsch's) nearly invariant calculus for parabolic  

E-Print Network (OSTI)

Bibliography Parabolic Geometries and Weyl connections Nearly invariant calculus (W¨unsch's) nearly invariant calculus for parabolic geometries Jan Slov´ak Masaryk University, Brno, Czech Republic joint work;Bibliography Parabolic Geometries and Weyl connections Nearly invariant calculus Structure 1 Bibliography 2

Olver, Peter

76

ON CARLEMAN ESTIMATES FOR ELLIPTIC AND PARABOLIC OPERATORS. APPLICATIONS TO UNIQUE CONTINUATION AND CONTROL OF PARABOLIC  

E-Print Network (OSTI)

ON CARLEMAN ESTIMATES FOR ELLIPTIC AND PARABOLIC OPERATORS. APPLICATIONS TO UNIQUE CONTINUATION AND CONTROL OF PARABOLIC EQUATIONS J´ER ^OME LE ROUSSEAU AND GILLES LEBEAU Abstract. Local and global Carleman and parabolic operators by means of semi-classical microlocal techniques. Optimality results for these estimates

Paris-Sud XI, Université de

77

THE PARABOLIC-PARABOLIC KELLER-SEGEL SYSTEM WITH CRITICAL DIFFUSION AS A GRADIENT FLOW IN Rd  

E-Print Network (OSTI)

THE PARABOLIC-PARABOLIC KELLER-SEGEL SYSTEM WITH CRITICAL DIFFUSION AS A GRADIENT FLOW IN Rd , d 3 ADRIEN BLANCHET1 AND PHILIPPE LAURENC¸OT2 Abstract. It is known that, for the parabolic-elliptic Keller for the parabolic-parabolic Keller-Segel system with critical porous-medium type diffusion in dimension Rd , d 3

Paris-Sud XI, Université de

78

Parabolic Deligne-Lusztig varieties  

E-Print Network (OSTI)

Motivated by the Brou\\'e conjecture on blocks with abelian defect groups for finite reductive groups, we study "parabolic" Deligne-Lusztig varieties and construct on those which occur in the Brou\\'e conjecture an action of a braid monoid, whose action on their $\\ell$-adic cohomology will conjecturally factor trough a cyclotomic Hecke algebra. In order to construct this action, we need to enlarge the set of varieties we consider to varieties attached to a "ribbon category"; this category is a {\\em Garside category}, which plays an important role in our proof, so we devote the first part of our paper to the necessary background on Garside categories.

Digne, François

2011-01-01T23:59:59.000Z

79

PARABOLIC COMPARISON PRINCIPLE AND QUASIMINIMIZERS IN METRIC MEASURE SPACES  

E-Print Network (OSTI)

PARABOLIC COMPARISON PRINCIPLE AND QUASIMINIMIZERS IN METRIC MEASURE SPACES JUHA KINNUNEN AND MATHIAS MASSON Abstract. We give several characterizations of parabolic (quasisuper)- minimizers prove a version of com- parison principle for super- and subminimizers on parabolic space-time cylinders

Kinnunen, Juha

80

A discrete BGK approximation for strongly degenerate parabolic problems  

E-Print Network (OSTI)

A discrete BGK approximation for strongly degenerate parabolic problems with boundary conditions F strongly degenerate hyperbolic--parabolic equations with initial boundary condition. We prove a priori -- strongly degenerate parabolic equations -- singular perturbation problems -- BGK models 1 Introduction

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


81

A Note on Parabolic Subgroups of a Coxeter Group  

E-Print Network (OSTI)

The aim of this note is to prove that the parabolic closure of any subset of a Coxeter group is a parabolic subgroup. To obtain that, several technical lemmas on the root system of a parabolic subgroup are established.

Dongwen Qi

2008-01-01T23:59:59.000Z

82

NREL: TroughNet - Parabolic Trough Power Plant Market, Economic...  

NLE Websites -- All DOE Office Websites (Extended Search)

Parabolic Trough Power Plant Market, Economic Assessment and Deployment Parabolic trough technology is the most commercially mature, large-scale solar power technology in the...

83

NREL: TroughNet - Parabolic Trough FAQs  

NLE Websites -- All DOE Office Websites (Extended Search)

Parabolic Trough FAQs Parabolic Trough FAQs Find answers to frequently asked questions about parabolic trough solar technology. Question topics include: Central station solar benefits Economic and environmental benefits Electricity cost Installation and operation Land use Large-scale vs. distributed power Past construction decline Photovoltaics comparison Power plant cost Power plant siting Technology potential Water use Some of the following documents are available as Adobe Acrobat PDFs. How much does a parabolic trough power plant cost? The cost of a parabolic trough power plant depends on many factors such as plant size, whether thermal energy storage is included, and whether the solar field has been enlarged to increase the annual plant capacity factor. Based on these considerations the current capital cost for large

84

QED with a parabolic mirror  

E-Print Network (OSTI)

We investigate the quantum electrodynamics of a single two-level atom located at the focus of a parabolic cavity. We first work out the modifications of the spontaneous emission induced by the presence of this boundary in the optical regime, where the dipole and the rotating-wave approximations apply. Furthermore, the single-photon state that leaves the cavity asymptotically is determined. The corresponding time-reversed single-photon quantum state is capable of exciting the atom in this extreme multimode scenario with near-unit probability. Using semiclassical methods, we derive a photon-path representation for the relevant transition amplitudes and show that it constitutes a satisfactory approximation for a wide range of wavelengths.

G. Alber; J. Z. Bernád; M. Stobi?ska; L. L. Sánchez-Soto; G. Leuchs

2013-05-11T23:59:59.000Z

85

S-Parabolic manifolds A. Aytuna and A. Sadullaev  

E-Print Network (OSTI)

S-Parabolic manifolds A. Aytuna and A. Sadullaev Abstract. A Stein manifold is called S parabolic. If a continuous special plurisubharmonic exits then we will call the manifold S parabolic: In one dimensional case of dimension n is called S parabolic in case there exits a special plurisubharmonic function 2 PSH (X

Yanikoglu, Berrin

86

ERGODIC THEORY OF PARABOLIC HORSESHOES MARIUSZ URBANSKI AND CHRISTIAN WOLF  

E-Print Network (OSTI)

ERGODIC THEORY OF PARABOLIC HORSESHOES MARIUSZ URBA´NSKI AND CHRISTIAN WOLF Abstract. In this paper parabolic fixed point and possibly also on Ws (). We call f a parabolic horseshoe map. In order to analyze of an embedded parabolic iterated function system and to apply the developed theory of the symbolic -finite

Urbanski, Mariusz

87

ERGODIC THEORY OF PARABOLIC HORSESHOES MARIUSZ URBANSKI AND CHRISTIAN WOLF  

E-Print Network (OSTI)

ERGODIC THEORY OF PARABOLIC HORSESHOES MARIUSZ URBA´NSKI AND CHRISTIAN WOLF Abstract. In this paper parabolic fixed point and possibly also on Ws (). We call f a parabolic horseshoe map. In order to analyze the pressure function to the pressure of an embedded parabolic iterated function system and to apply

Wolf, Christian

88

PARABOLIC RAYNAUD BUNDLES INDRANIL BISWAS AND GEORG HEIN  

E-Print Network (OSTI)

PARABOLIC RAYNAUD BUNDLES INDRANIL BISWAS AND GEORG HEIN Abstract. Let X be an irreducible smooth and N 2 a fixed integer. For any pair (r, d) N Ă? 1 N Z, there exists a parabolic vector bundle Rr,d, on X, with parabolic structure over S and all parabolic weights in 1 N Z, that has the following

Hein, Georg

89

Large-angle Parabolic Equation Methods James T. Kirby*  

E-Print Network (OSTI)

CHAPTER 32 Large-angle Parabolic Equation Methods James T. Kirby* Large-angle parabolic equation of the parabolic equation method (PEM) to any relevant wave propagation problem implies that a principal is to examine two methods of extending the basic parabolic equation method to include large-angle effects

Kirby, James T.

90

On a parabolic logarithmic Sobolev inequality H. Ibrahim ,,, R. Monneau  

E-Print Network (OSTI)

On a parabolic logarithmic Sobolev inequality H. Ibrahim ,,, R. Monneau December 19, 2008 Abstract a parabolic version of the Kozono-Taniuchi inequality by means of anisotropic (parabolic) BMO norm. More precisely we give an upper bound for the L norm of a function in terms of its parabolic BMO norm, up

Monneau, RĂ©gis

91

Definition: Parabolic trough | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Parabolic trough Jump to: navigation, search Dictionary.png Parabolic trough A solar energy conversion device that uses a trough covered with a highly reflective surface to focus sunlight onto a linear absorber containing a working fluid that can be used to spin a turbine for electricity generation; with a single-axis sun-tracking system, the configuration of a parabolic trough can track the sun from east to west during the day.[1][2][3] View on Wikipedia Wikipedia Definition A parabolic trough is a type of solar thermal collector that is straight in one dimension and curved as a parabola in the other two, lined with a polished metal mirror. The energy of sunlight which enters the

92

Rational Approximation for a Quasilinear Parabolic Equation  

E-Print Network (OSTI)

Approximation theorems, analogous to known results for linear elliptic equations, are obtained for solutions of the heat equation. Via the Cole-Hopf transformation, this gives rise to approximation theorems for a nonlinear parabolic equation, Burgers' equation.

P. M. Gauthier; N. Tarkhanov

2007-09-22T23:59:59.000Z

93

Parabolic cylinder functions implemented in Matlab  

E-Print Network (OSTI)

Routines for computation of Weber's parabolic cylinder functions and their derivatives are implemented in Matlab for both moderate and great values of the argument. Standard, real solutions are considered. Tables of values are included.

E. Cojocaru

2009-01-15T23:59:59.000Z

94

Parabolic Trough Solar Thermal Electric Power Plants  

DOE Green Energy (OSTI)

Although many solar technologies have been demonstrated, parabolic trough solar thermal electric power plant technology represents one of the major renewable energy success stories of the last two decades.

Not Available

2003-06-01T23:59:59.000Z

95

Parabolic equations without a minimum principle  

E-Print Network (OSTI)

In this thesis, we consider several parabolic equations for which the minimum principle fails. We first consider a two-point boundary value problem for a one dimensional diffusion equation. We show the uniqueness and ...

Pang, Huadong

2007-01-01T23:59:59.000Z

96

Lighting.  

SciTech Connect

Since lighting accounts for about one-third of the energy used in commercial buildings, there is opportunity to conserve. There are two ways to reduce lighting energy use: modify lighting systems so that they used less electricity and/or reduce the number of hours the lights are used. This booklet presents a number of ways to do both. Topics covered include: reassessing lighting levels, reducing lighting levels, increasing bulb & fixture efficiency, using controls to regulate lighting, and taking advantage of daylight.

United States. Bonneville Power Administration.

1992-09-01T23:59:59.000Z

97

Lighting  

Energy.gov (U.S. Department of Energy (DOE))

There are many different types of artificial lights, all of which have different applications and uses. Types of lighting include:

98

Parabolic trough solar collectors : design for increasing efficiency  

E-Print Network (OSTI)

Parabolic trough collectors are a low cost implementation of concentrated solar power technology that focuses incident sunlight onto a tube filled with a heat transfer fluid. The efficiency and cost of the parabolic trough ...

Figueredo, Stacy L. (Stacy Lee), 1981-

2011-01-01T23:59:59.000Z

99

Design considerations for parabolic-cylindrical solar collectors  

DOE Green Energy (OSTI)

This report presents in some detail the various significant factors which influence the design of parabolic-cylindrical solar collectors.

Treadwell, G.W.

1976-07-01T23:59:59.000Z

100

PARABOLIC SUBGROUPS OF GARSIDE GROUPS II : EDDY GODELLE  

E-Print Network (OSTI)

PARABOLIC SUBGROUPS OF GARSIDE GROUPS II : RIBBONS EDDY GODELLE Abstract. We introduce parabolic subgroupoids and provide a groupoid presentation. In order to established the latter result, we subgroups, namely the standard parabolic subgroups, which are the subgroups generated by a subset

Paris-Sud XI, Université de

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


101

PARABOLIC DELIGNE-LUSZTIG VARIETIES. FRANCOIS DIGNE AND JEAN MICHEL  

E-Print Network (OSTI)

PARABOLIC DELIGNE-LUSZTIG VARIETIES. FRANC¸OIS DIGNE AND JEAN MICHEL Abstract. Motivated by the Brou´e conjecture on blocks with abelian defect groups for finite reductive groups, we study "parabolic categories. 1. Introduction In this paper, we study "parabolic" Deligne-Lusztig varieties, one of the main

Paris-Sud XI, Université de

102

INITIAL BOUNDARY VALUE PROBLEMS FOR A QUASILINEAR PARABOLIC SYSTEM  

E-Print Network (OSTI)

INITIAL BOUNDARY VALUE PROBLEMS FOR A QUASILINEAR PARABOLIC SYSTEM IN THREE-PHASE CAPILLARY FLOW problems for a quasi- linear parabolic system motivated by three-phase ow in porous medium in the presence quasilinear parabolic sys- tems of the form (1.1) u t + f(u) x = (B(u)u x ) x ; 0

103

Convergence properties of the local defect correction method for parabolic  

E-Print Network (OSTI)

Convergence properties of the local defect correction method for parabolic problems R. Minero , H for parabolic problems presented in [14]. We derive a general expression for the iteration matrix of the method, domain decomposition and regridding. In [14] LDC is generalized to solve parabolic partial differential

Eindhoven, Technische Universiteit

104

Parabolic PDEs and Deterministic Games Robert V. Kohn  

E-Print Network (OSTI)

Parabolic PDEs and Deterministic Games Robert V. Kohn Courant Institute, NYU Joint work with Sylvia Serfaty ICIAM07, Zurich, July 2007 Robert V. Kohn Courant Institute, NYU Parabolic PDEs and Deterministic. Kohn Courant Institute, NYU Parabolic PDEs and Deterministic Games #12;Goals and perspective Part 1

105

Generation of parabolic pulses and applications for optical telecommunications  

E-Print Network (OSTI)

Generation of parabolic pulses and applications for optical telecommunications Christophe Finot 1.Finot@u-bourgogne.fr ABSTRACT Parabolic pulses in optical fibers have stimulated an increasing number of applications. We review amplifiers, optical pulse processing techniques 1. INTRODUCTION Parabolic pulse generation and propagation

Paris-Sud XI, Université de

106

Di usive Kinetic Explicit Schemes for Nonlinear Degenerate Parabolic Systems  

E-Print Network (OSTI)

Di#11;usive Kinetic Explicit Schemes for Nonlinear Degenerate Parabolic Systems #3; D. Aregba parabolic systems. These schemes are based on discrete BGK models where both characteristic velocities. Evje and K.H. Karlsen [15] and of M. Espedal and K.H. Karlsen [14]. For the theory of general parabolic

107

Curvilinear parabolic approximation for surface wave transformation with wavecurrent interaction  

E-Print Network (OSTI)

Curvilinear parabolic approximation for surface wave transformation with wave­current interaction not be an appropriate method for the purpose of simplifying the curvilinear parabolic approximation of the vector form of the wave­current equation given by Kirby [Higher-order approximations in the parabolic equation method

Kirby, James T.

108

Theory of parabolic pulse generation in tapered Anton I. Latkin  

E-Print Network (OSTI)

Theory of parabolic pulse generation in tapered fiber Anton I. Latkin Institute of Automation and differences between high-power parabolic pulse generation in an active me- dium and in tapered fiber of parabolic pulse generation without an external pump and determine the limita- tions of this approach. © 2007

Turitsyn, Sergei K.

109

Parabolic surfaces in hyperbolic space with constant Gaussian curvature  

E-Print Network (OSTI)

Parabolic surfaces in hyperbolic space with constant Gaussian curvature Rafael L´opez Departamento@ugr.es Keywords: hyperbolic space, parabolic surface, Gaussian curvature MSC 2000 subject classification: 53A10, 53C45 Abstract A parabolic surface in hyperbolic space H3 is a surface invariant by a group

LĂłpez, Rafael

110

On Parallel Asynchronous HighOrder Solutions of Parabolic PDEs  

E-Print Network (OSTI)

On Parallel Asynchronous High­Order Solutions of Parabolic PDEs appeared in Numerical Algorithms Parabolic PDEs. They are asynchronous in the sense that each processor is allowed to advance at its own and synchronous finite difference methods, parabolic finite difference approximations with constant coefficients

Averbuch, Amir

111

Compound parabolic concentrators for narrowband wireless infrared receivers  

E-Print Network (OSTI)

Compound parabolic concentrators for narrowband wireless infrared receivers Keang-Po Ho Joseph M and hollow compound parabolic concentrators (CPCs), for use in free-space infrared communication receivers terms: compound parabolic concentrators (CPCs); optical bandpass fil- ters; Monte Carlo ray tracing

Kahn, Joseph M.

112

Rotational and Parabolic Surfaces in PSL2(R, ) and Applications  

E-Print Network (OSTI)

Rotational and Parabolic Surfaces in PSL2(R, ) and Applications By Carlos Espinoza Pe~nafiel 1 of either rotational isometries or parabolic isometries, immersed into the homogeneous manifold PSL2(R, ). Also, we give some applications. Keywords. Constant mean curvature. Rotational surfaces. Parabolic

Paris-Sud XI, Université de

113

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION  

E-Print Network (OSTI)

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION GEORGIOS AKRIVIS Abstract. We consider a model initial and boundary value problem for the wide-angle `parabolic' equation Lur = icu, the wide-angle `parabolic'equation of underwater acoustics. Given R > 0, µ 0, > 0, , and q real

Akrivis, Georgios

114

Parabolic resonances and instabilities Vered Rom-Kedara)  

E-Print Network (OSTI)

Parabolic resonances and instabilities Vered Rom-Kedara) Department of Applied Mathematics 1996; accepted for publication 30 August 1996 A parabolic resonance is formed when an integrable two-degrees-of-freedom d.o.f. Hamiltonian system possessing a circle of parabolic fixed points is perturbed. It is proved

115

PARABOLIC WAVE COMPUTATIONS IN NON-ORTHOGONAL COORDINATE  

E-Print Network (OSTI)

· PARABOLIC WAVE COMPUTATIONS IN NON-ORTHOGONAL COORDINATE SYSTEMS By James T. Kirby,1 Associate Member, ASCE ABSTRACT: A recent development of a parabolic equation method for wave prop- agation developed in applying the parabolic equation method (PEM) for surface wave propagation in non

Kirby, James T.

116

Elastic approximation for a solar parabolic February 29, 2012  

E-Print Network (OSTI)

Elastic approximation for a solar parabolic trough February 29, 2012 Gang Xiao (University of Nice, France) Abstract For the production of the reective surface of a solar parabolic trough concentrator energy solutions. Introduction A parabolic trough [8] is a concentrating solar thermal energy collector

Paris-Sud XI, Université de

117

THE STRUCTURE OF TWO-PARABOLIC SPACE: PARABOLIC DUST AND ITERATION.  

E-Print Network (OSTI)

Abstract. A non-elementary Möbius group generated by twoparabolics is determined up to conjugation by one complex parameter and the parameter space has been extensively studied. In this paper, we use the results of [7] to obtain an additional structure for the parameter space, which we term the two-parabolic space. This structure allows us to identify groups that contain additional conjugacy classes of primitive parabolics, which following [14] we call parabolic dust groups, non-free groups off the real axis, and groups that are both parabolic dust and non-free; some of these contain Z × Z subgroups. The structure theorem also attaches additional geometric structure to discrete and non-discrete groups lying in given regions of the parameter space including a new explicit construction of some non-classical T-Schottky groups. 1.

Jane Gilman

2007-01-01T23:59:59.000Z

118

On a parabolic operator of dissipative systems  

E-Print Network (OSTI)

A parabolic integro differential operator operator L suitable to describe many phenomena in various physical fields,is considered. By means of equivalence between L and the third order equation which describe the evolution inside an exponentially shaped Josephson junction (ESJJ), an asymptotic analysis for (ESJJ) is achieved, evaluating explicitly boundary contributions related to the Dirichlet problem.

Monica De Angelis

2013-07-07T23:59:59.000Z

119

Parabolic systems with coupled boundary conditions  

E-Print Network (OSTI)

We consider elliptic operators with operator-valued coefficients and discuss the associated parabolic problems. The unknowns are functions with values in a Hilbert space $W$. The system is equipped with a general class of coupled boundary conditions of the form $f_{|\\partial\\Omega}\\in \\mathcal Y$ and $\\frac{\\partial f}{\\partial \

Stefano Cardanobile; Delio Mugnolo

2008-12-19T23:59:59.000Z

120

Texas Electric Lighting Report  

NLE Websites -- All DOE Office Websites (Extended Search)

electric lighting electric lighting The SNAP House's lighting design aims for elegant simplicity in concept, use, and maintenance. Throughout the house, soft, ambient light is juxtaposed with bright, direct task lighting. All ambient and most task lighting is integrated directly into the architectural design of the house. An accent light wall between the bedroom and bathroom provides a glowing light for nighttime navigation.

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


121

THE CHERN CHARACTER OF A PARABOLIC BUNDLE, AND A PARABOLIC REZNIKOV THEOREM IN THE CASE OF FINITE ORDER AT INFINITY  

E-Print Network (OSTI)

In this paper, we obtain an explicit formula for the Chern character of a locally abelian parabolic bundle in terms of its constituent bundles. Several features and variants of parabolic structures are discussed. Parabolic bundles arising from logarithmic connections form an important class of examples. As an application, we consider the situation when the local monodromies are semi-simple and are of finite order at infinity. In this case the parabolic Chern classes of the associated locally abelian parabolic bundle are deduced to be zero in the rational Deligne cohomology in degrees ? 2.

Jaya Nn Iyer; Carlos T Simpson

2007-01-01T23:59:59.000Z

122

Fig. 1. Artist's concept of the 1-D parabolic cylinder reflector. The re-flector has a parabolic shape in the short dimension and a flat profile in  

E-Print Network (OSTI)

Fig. 1. Artist's concept of the 1-D parabolic cylinder reflector. The re- flector has a parabolic [1]. A stationary linear parabolic reflector with a diameter of 1.6 m and a length of 2 m would

Ruf, Christopher

123

Experimental parabolic trough collector performance characterization  

DOE Green Energy (OSTI)

Experimental data from the Collector Module Test Facility (CMTF) at Sandia National Laboratories, Albuquerque, are used to develop a collector performance model and characterize three parabolic trough solar collectors. The independent variables used in the model are selected and fitted to the experimental data using a multiple linear regression technique. The collector model developed accounts for optical performance, including incident angle effects and thermal losses, both linear and non-linear.

Lukens, L.L.

1981-05-01T23:59:59.000Z

124

Parabolic Trough Organic Rankine Cycle Power Plant  

DOE Green Energy (OSTI)

Arizona Public Service (APS) is required to generate a portion of its electricity from solar resources in order to satisfy its obligation under the Arizona Environmental Portfolio Standard (EPS). In recent years, APS has installed and operates over 4.5 MWe of fixed, tracking, and concentrating photovoltaic systems to help meet the solar portion of this obligation and to develop an understanding of which solar technologies provide the best cost and performance to meet utility needs. During FY04, APS began construction of a 1-MWe parabolic trough concentrating solar power plant. This plant represents the first parabolic trough plant to begin construction since 1991. The plant will also be the first commercial deployment of the Solargenix parabolic trough collector technology developed under contract to the National Renewable Energy Laboratory (NREL). The plant will use an organic Rankine cycle (ORC) power plant, provided by Ormat. The ORC power plant is much simpler than a conventional steam Rankine cycle power plant and allows unattended operation of the facility.

Canada, S.; Cohen, G.; Cable, R.; Brosseau, D.; Price, H.

2005-01-01T23:59:59.000Z

125

LIGHTING CONTROLS: SURVEY OF MARKET POTENTIAL  

E-Print Network (OSTI)

REFERENCES Task Report to Lighting Systems Research,Berkeley Laboratory, "Lighting Control System Market1980). Task Report to Lighting Systems Research, Lawrence

Verderber, R.R.

2010-01-01T23:59:59.000Z

126

NREL: TroughNet - Parabolic Trough Power Plant System Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

Parabolic Trough Power Plant System Technology Parabolic Trough Power Plant System Technology A parabolic trough solar power plant uses a large field of collectors to supply thermal energy to a conventional power plant. Because they use conventional power cycles, parabolic trough power plants can be hybridized-other fuels can be used to back up the solar power. Like all power cycles, trough power plants also need a cooling system to transfer waste heat to the environment. Parabolic trough power plant technologies include: Direct steam generation Fossil-fired (hybrid) backup Operation and maintenance Power cycles Steam Rankine Organic Rankine Combined Wet and dry cooling Power Cycles A photo of an aerial view of a power plant in the middle of a solar field with rows and rows of parabolic troughs tracking. The cooling towers can be seen with the water plume rising into the air. The white water tanks can be seen in the background.

127

Optimal Heat Collection Element Shapes for Parabolic Trough Concentrators  

DOE Green Energy (OSTI)

For nearly 150 years, the cross section of the heat collection tubes used at the focus of parabolic trough solar concentrators has been circular. This type of tube is obviously simple and easily fabricated, but it is not optimal. It is shown in this article that the optimal shape, assuming a perfect parabolic figure for the concentrating mirror, is instead oblong, and is approximately given by a pair of facing parabolic segments.

Bennett, C

2007-11-15T23:59:59.000Z

128

Poincar'e polynomial of the moduli spaces of parabolic bundles  

E-Print Network (OSTI)

Poincar'e polynomial of the moduli spaces of parabolic bundles Yogish I. Holla March 7, 2000 School of the moduli spaces of semi­stable parabolic bundles on a curve. The quasi parabolic analogue of the Siegel for determine the Betti numbers of the moduli of semistable parabolic bundles on a curve (when parabolic semi

Holla, Yogish I.

129

Hydrogen Removal From Heating Oil of a Parabolic Trough ...  

Hydrogen Removal From Heating Oil of a Parabolic Trough Increases the Life of the Trough and its Components A Method to Selectively Remove & Measure Hydrogen Gas from ...

130

Field Survey of Parabolic Trough Receiver Thermal Performance: Preprint  

SciTech Connect

This paper describes a technique that uses an infrared camera to evaluate the in-situ thermal performance of parabolic trough receivers at operating solar power plants.

Price, H.; Forristall, R.; Wendelin, T.; Lewandowski, A.; Moss, T.; Gummo, C.

2006-04-01T23:59:59.000Z

131

Parabolic Trough Solar Thermal Electric Power Plants (Fact Sheet)  

DOE Green Energy (OSTI)

This fact sheet provides an overview of the potential for parabolic trough solar thermal electric power plants, especially in the Southwestern U.S.

Not Available

2006-07-01T23:59:59.000Z

132

post-pareto analysis for multiobjective parabolic control systems  

E-Print Network (OSTI)

Jul 29, 2012 ... POST-PARETO ANALYSIS FOR MULTIOBJECTIVE PARABOLIC CONTROL SYSTEMS. Henri Bonnel (bonnel ***at*** univ-nc.nc). Abstract: In ...

133

Hydrogen Removal From Heating Oil of a Parabolic Trough ...  

A Method to Selectively Remove & Measure Hydrogen Gas from a Fluid Volume Parabolic trough power plants use concentrated solar thermal energy to ...

134

Estimates in the Generalized Morrey Space for Linear Parabolic Systems.  

E-Print Network (OSTI)

??The purpose of the this paper is to study the parabolic system uti - D_?(aij??D_?uj) = -div fi in the generalized Morrey Space L_?2,? .… (more)

McBride, Matthew Scott

2007-01-01T23:59:59.000Z

135

Long-term average performance benefits of parabolic trough improvements  

DOE Green Energy (OSTI)

Improved parabolic trough concentrating collectors will result from better design, improved fabrication techniques, and the development and utilization of improved materials. This analysis quantifies the relative merit of various technological advancements in improving the long-term average performance of parabolic trough concentrating collectors and presents them graphically as a function of operating temperature for north-south, east-west, and polar mounted parabolic troughs. Substantial annual energy gains (exceeding 50% at 350/sup 0/C) are shown to be attainable with improved parabolic troughs.

Gee, R.; Gaul, H.; Kearney, D.; Rabl, A.

1979-10-01T23:59:59.000Z

136

Simplified Methodology for Designing Parabolic Trough Solar Power Plants.  

E-Print Network (OSTI)

??The performance of parabolic trough based solar power plants over the last 25 years has proven that this technology is an excellent alternative for the… (more)

Vasquez Padilla, Ricardo

2011-01-01T23:59:59.000Z

137

Parabolic trough solar collectors : design for increasing efficiency.  

E-Print Network (OSTI)

??Parabolic trough collectors are a low cost implementation of concentrated solar power technology that focuses incident sunlight onto a tube filled with a heat transfer… (more)

Figueredo, Stacy L. (Stacy Lee), 1981-

2011-01-01T23:59:59.000Z

138

Simplified Methodology for Designing Parabolic Trough Solar Power Plants.  

E-Print Network (OSTI)

?? The performance of parabolic trough based solar power plants over the last 25 years has proven that this technology is an excellent alternative for… (more)

Vasquez Padilla, Ricardo

2011-01-01T23:59:59.000Z

139

Parabolic Trough VSHOT Optical Characterization in 2005-2006 (Presentation)  

DOE Green Energy (OSTI)

This presentation regarding parabolic trough VSHOT optical characterization describes trough deployment and operation phases including: development, manufacture/installation, and maintenance/operation.

Wendelin, T.

2006-02-01T23:59:59.000Z

140

Single-photon single-ion interaction in free space configuration in front of a parabolic mirror  

E-Print Network (OSTI)

The efficient interaction between single photons and single matter objects in free space is of key importance for quantum technologies. An experimental setup for testing this possibility involves single two-level ion trapped at the focus of a parabolic metallic mirror. We study the conditions for the setup, under which the assumption about the free-space mode structure of the radiation field in the vicinity of the atom is justified. In our analysis we apply vectorial properties of light by including polarization degree of freedom. We look for possible changes in the spontaneous emission rate of the atom resulting from the presence of the parabolic boundary conditions.

Magdalena Stobi?ska; Robert Alicki

2009-05-25T23:59:59.000Z

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


141

Alignment method for parabolic trough solar concentrators  

DOE Patents (OSTI)

A Theoretical Overlay Photographic (TOP) alignment method uses the overlay of a theoretical projected image of a perfectly aligned concentrator on a photographic image of the concentrator to align the mirror facets of a parabolic trough solar concentrator. The alignment method is practical and straightforward, and inherently aligns the mirror facets to the receiver. When integrated with clinometer measurements for which gravity and mechanical drag effects have been accounted for and which are made in a manner and location consistent with the alignment method, all of the mirrors on a common drive can be aligned and optimized for any concentrator orientation.

Diver, Richard B. (Albuquerque, NM)

2010-02-23T23:59:59.000Z

142

Numerical Schemes for Rough Parabolic Equations  

SciTech Connect

This paper is devoted to the study of numerical approximation schemes for a class of parabolic equations on (0,1) perturbed by a non-linear rough signal. It is the continuation of Deya (Electron. J. Probab. 16:1489-1518, 2011) and Deya et al. (Probab. Theory Relat. Fields, to appear), where the existence and uniqueness of a solution has been established. The approach combines rough paths methods with standard considerations on discretizing stochastic PDEs. The results apply to a geometric 2-rough path, which covers the case of the multidimensional fractional Brownian motion with Hurst index H>1/3.

Deya, Aurelien, E-mail: deya@iecn.u-nancy.fr [Universite de Nancy 1, Institut Elie Cartan Nancy (France)

2012-04-15T23:59:59.000Z

143

DEGENERATE-PARABOLIC PARTIAL DIFFERENTIAL EQUATIONS WITH UNBOUNDED COEFFICIENTS, MARTINGALE PROBLEMS, AND A  

E-Print Network (OSTI)

DEGENERATE-PARABOLIC PARTIAL DIFFERENTIAL EQUATIONS WITH UNBOUNDED COEFFICIENTS, MARTINGALE four intertwined problems, motivated by mathematical finance, concerning degenerate-parabolic partial differential operators and degenerate diffusion processes. First, we consider a parabolic partial differential

144

Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough Federal Technology Alert covers parabolic-trough solar...

145

A new parabolic trough solar collector P. Kohlenbach1  

E-Print Network (OSTI)

) power generation system. The parabolic trough collectors have been installed in the National Solar-selective paint. The absorber operates in a 50mm non-evacuated glass tube to minimize convection losses. Thermal and power generation (CHP), CSIRO has built a solar thermal parabolic trough collector field which

146

Solar parabolic dish annual technology evaluation report. Fiscal year 1982  

DOE Green Energy (OSTI)

This report summarizes the activities of the JPL Solar Thermal Power Systems Parabolic Dish Project for FY 1982. Included are discussions on designs of module development including their concentrator, receiver, and power conversion subsystems. Analyses and test results, along with progress on field tests, Small Community Experiment System development, and tests at the Parabolic Dish Test Site are also included.

Not Available

1983-09-15T23:59:59.000Z

147

PARABOLIC DELIGNE-LUSZTIG VARIETIES. FRANCOIS DIGNE AND JEAN MICHEL  

E-Print Network (OSTI)

PARABOLIC DELIGNE-LUSZTIG VARIETIES. FRANC¸OIS DIGNE AND JEAN MICHEL Abstract. Motivated by the Brou´e conjecture on blocks with abelian defect groups for finite reductive groups, we study "parabolic of a braid monoid, whose action on their -adic cohomology will conjecturally factor trough a cyclotomic Hecke

148

An Optical Characterization Technique for Parabolic Trough Solar Collectors Using Images of the Absorber Reection.  

E-Print Network (OSTI)

?? As the concentrating solar power industry competes to develop a less-expensive parabolic trough collector, assurance is needed that new parabolic trough collectors maintain accurate… (more)

Owkes, Jeanmarie Kathleen

2013-01-01T23:59:59.000Z

149

Lighting Group: Sources and Ballasts  

NLE Websites -- All DOE Office Websites (Extended Search)

incorporating LEDs into tomorrows task lights, to reducing light entrapment within the LED, to fundamental research into how Organic Lighting Emitting Diodes operate. LED and...

150

Parabolic refined invariants and Macdonald polynomials  

E-Print Network (OSTI)

A string theoretic derivation is given for the conjecture of Hausel, Letellier, and Rodriguez-Villegas on the cohomology of character varieties with marked points. Their formula is identified with a refined BPS expansion in the stable pair theory of a local root stack, generalizing previous work of the first two authors in collaboration with G. Pan. Haiman's geometric construction for Macdonald polynomials is shown to emerge naturally in this context via geometric engineering. In particular this yields a new conjectural relation between Macdonald polynomials and refined local orbifold curve counting invariants. The string theoretic approach also leads to a new spectral cover construction for parabolic Higgs bundles in terms of holomorphic symplectic orbifolds.

Wu-yen Chuang; Duiliu-Emanuel Diaconescu; Ron Donagi; Tony Pantev

2013-11-14T23:59:59.000Z

151

Steam generation in compound parabolic concentrator collectors  

SciTech Connect

This report describes the advantages of generating steam directly in a nonimaging compound parabolic concentrator (CPC) collector rather than using a heat-transfer fluid and a secondary heat exchanger. The predicted performance advantages from generating steam directly in CPC collectors are significant, and that performance has ben verified using a collector built and tested at Argonne National Laboratory. The collector and the method used to test its operation in a steam-generating mode are described. Test results are included for a 6.4-m/sup 2/ array of evacuated tube collectors with an advanced absorber coating, silver reflectors, and tubes oriented in a north-south configuration. Also described are the test methods and results for indoor testing for heat loss by the collectors and outdoor testing of their instantaneous optical efficiency.

Allen, J.W.; Schertz, W.W.; Wantroba, A.S.

1985-08-01T23:59:59.000Z

152

Task Plans  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Task Plans Task Plans This page contains links to a tentative listing of active and closed TEC Task Plans. Final status of these task plans will be determined after the July 2000 TEC meeting. Task Plan Number/Title DOE Lead Staff Last Update Comment Status/ New No. After 7/27/00 GP-1, Section 180(c) Coordination (begun 1/96) C. Macaluso 7/98 DOE published a Revised Proposed Policy and Procedures in April 1998; no final policy will be issued until a definitive date for NWPA shipments is determined, based on site suitability or other legislative direction. To the extent that any issues related to Section 180(c) arise in TEC meetings, they are being discussed in the context of the consolidated grant topic group which is covered by another task plan. Closed

153

Two dimensional compound parabolic concentrating collectors. Final report  

SciTech Connect

Seven different compound parabolic concentrating (CPC) collector designs were tested by the ray trace method. The comparison of the collector was performed by simulating sunlight striking the designs at various angles of the sun during the course of the day. All of the CPC solar collector designs used the same type of reflective material, Kinglux reflective aluminum, which is a highly reflective surface used in solar applications. The CPC solar collector designs were subjected to a light source consisting of one helium-neon laser. The laser, to represent the effect of sunlight on the stationary CPC solar collector, was slowly moved across the aperture opening. This is explained in detail. Mathematic equations were used to develop the different CPC solar collector designs. The different shapes for each collector design, were acquired by varying the size of the absorber tube, and also by varying the acceptance angle of the collector. The seven CPC solar collector designs were tested, and the optimal design was selected for experimental testing.

Henry, J.P.; Gamble, N.T.; Cassidy, S.A.

1983-12-31T23:59:59.000Z

154

NREL: TroughNet - Parabolic Trough Technology Overview  

NLE Websites -- All DOE Office Websites (Extended Search)

Technology Overview Technology Overview Parabolic trough solar power technology offers an environmentally sound and increasingly cost-effective energy source. Here you'll find overviews about the following parabolic trough power plant technologies: Solar Field Collector balance of system Concentrator structure Mirrors Receivers Thermal Energy Storage Molten-salt heat transfer fluid Storage media Storage systems Power Plant Systems Direct steam generation Fossil-fired hybrid backup Power cycles Wet and dry cooling Operation and maintenance For more detailed, technical information, see our publications on parabolic trough power plant technology. Printable Version TroughNet Home Technologies Solar Field Thermal Energy Storage Power Plant Systems Market & Economic Assessment Research & Development

155

NREL: TroughNet - Parabolic Trough System and Component Testing  

NLE Websites -- All DOE Office Websites (Extended Search)

System and Component Testing System and Component Testing Here you'll find information about parabolic trough system and components testing, as well facilities and laboratories used for testing. Tests include those for: Concentrator thermal efficiency Receiver thermal performance Mirror contour and collector alignment Mirror reflectivity and durability Some of the following documents are available as Adobe Acrobat PDFs. Download Adobe Reader. Concentrator Thermal Efficiency Testing Researchers and industry use the following facilities for testing parabolic trough collectors. AZTRAK Rotating Platform At Sandia National Laboratories' National Solar Thermal Test Facility (NSTTF), the AZTRAK rotating platform has been used to test several parabolic trough modules and receivers. Initially, researchers tested a

156

Solar thermal parabolic dish systems: technology and applications  

DOE Green Energy (OSTI)

This presentation surveys the status and some probable future courses of development of parabolic dish solar collector technology and some of the near-term and long-range applications of the technology. Included are fundamentals of the technology, descriptions of current collectors with particular emphasis on the types developed within the Department of Energy's Solar Thermal Program, descriptions of current systems and applications, key technical issues and tradeoff considerations which will affect the competition between parabolic dish systems and other solar thermal technologies, and, finally, a discussion of future possibilities for the development of parabolic dish technology.

Leonard, J.A.

1984-05-01T23:59:59.000Z

157

Self-similar parabolic plasmonic beams Arthur R. Davoyan,1,2,  

E-Print Network (OSTI)

Self-similar parabolic plasmonic beams Arthur R. Davoyan,1,2, * Sergei K. Turitsyn,3 and Yuri S support stable self-similar plasmonic waves with a parabolic profile. Simplicity of a parabolic shape on availability of the basic waveforms with simple shapes, e.g., square top- flat, triangular, parabolic, and so

Turitsyn, Sergei K.

158

NREL: TroughNet - 2007 Parabolic Trough Technology Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

2007 Parabolic Trough Technology Workshop 2007 Parabolic Trough Technology Workshop NREL hosted a parabolic trough technology workshop on March 8-9, 2007, in Golden, Colorado. It had three goals: Exchanging technical information Collaborating on SolarPaces projects: receiver testing and dry cooling Gathering industry input on laboratory R&D directions. The workshop featured presentations on the following parabolic trough power plant topics: Current and future market vision Project developments Solar resource assessment Technology trends Molten-salt heat transfer fluids Direct steam generation Advanced tools and testing capabilities Researchers also presented a poster session on laboratory capabilities. Note: if a presentation or poster isn't listed below, NREL hasn't yet received permission or approval to post it.

159

Guidelines for reporting parabolic trough solar electric system performance  

DOE Green Energy (OSTI)

The purpose of this activity is to develop a generic methodology which can be used to track and compare the performance of parabolic trough power plants. The approach needs to be general enough to work for all existing and future parabolic trough plant designs, provide meaningful comparisons of year to year performance, and allow for comparisons between dissimilar plant designs. The approach presented here uses the net annual system efficiency as the primary metric for evaluating the performance of parabolic trough power plants. However, given the complex nature of large parabolic trough plants, the net annual system efficiency by itself does not adequately characterize the performance of the plant. The approach taken here is to define a number of additional performance metrics which enable a more comprehensive understanding of overall plant performance.

Price, H.W.

1997-06-01T23:59:59.000Z

160

NREL: TroughNet - Parabolic Trough Thermal Energy Storage Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermal Energy Storage Technology One advantage of parabolic trough power plants is their potential for storing solar thermal energy to use during non-solar periods and to dispatch...

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


161

Shock stability analysis for Parabolized Navier-Stokes equations  

Science Conference Proceedings (OSTI)

Parabolized Navier-Stokes (PNS) techniques have been receiving increasing attention as an effective method for treating two and three dimensional high-speed gas flows. Since the method involves marching in a ''time like'' coordinate the problem size ...

Douglas D. Cline; Graham F. Carey

1988-12-01T23:59:59.000Z

162

Parabolic Equations and Markov Processes Over p-adic Fields  

E-Print Network (OSTI)

We construct and study a fundamental solution of Cauchy's problem for p-adic parabolic equations of a certain the type. The fundamental solution is the transition density of a p-adic Markov process.

W. A. Zuniga-Galindo

2006-12-11T23:59:59.000Z

163

Application of the Piecewise Parabolic Method (PPM) to Meteorological Modeling  

Science Conference Proceedings (OSTI)

The Piecewise Parabolic Method (PPM), a numerical technique developed in astrophysics for modeling fluid flows with strong shocks and discontinuities is adapted for treating sharp gradients in small-scale meteorological flows. PPM differs ...

Richard L. Carpenter Jr.; Kelvin K. Droegemeier; Paul R. Woodward; Carl E. Hane

1990-03-01T23:59:59.000Z

164

CLASSICAL TWO-PARABOLIC T-SCHOTTKY GROUPS  

E-Print Network (OSTI)

A T-Schottky group is a discrete group of Möbius transformations whose generators identify pairs of possibly-tangent Jordan curves on the complex sphere ? ?. If the curves are Euclidean circles, then the group is termed classical T-Schottky. We describe the boundary of the space of classical T-Schottky groups affording two parabolic generators within the larger parameter space of all-Schottky groups with two parabolic generators. This boundary is surprisingly different from that of the larger space. It is analytic, while the boundary of the larger space appears to be fractal. Approaching the boundary of the smaller space does not correspond to pinching; circles necessarily become tangent, but extra parabolics need not develop. As an application, we construct an explicit one parameter family of two parabolic generator non-classical T-Schottky groups.

Jane Gilman; Peter Waterman

2006-01-01T23:59:59.000Z

165

Parabolic-Trough Technology Roadmap | Open Energy Information  

Open Energy Info (EERE)

Parabolic-Trough Technology Roadmap Parabolic-Trough Technology Roadmap Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Parabolic-Trough Technology Roadmap Agency/Company /Organization: National Renewable Energy Laboratory, United States Department of Energy Sector: Energy Focus Area: Renewable Energy, Solar Topics: Technology characterizations Resource Type: Guide/manual Website: www.nrel.gov/csp/troughnet/pdfs/24748.pdf References: Parabolic-Trough Technology Roadmap[1] Overview "The working group reviewed the status of today's trough technologies, evaluated existing markets, identified potential future market opportunities, and developed a roadmap toward its vision of the industry's potential-including critical advancements needed over the long term to significantly reduce costs while further increasing

166

Arnold Schwarzenegger LIGHTING RESEARCH PROGRAM  

E-Print Network (OSTI)

fluorescent task lamp. The prototype used commercially available materials: 1watt light emitting diodes to the mounting board. Development of LightEmitting Diode Task Lamp using Advanced Technologies: Prototype 2 lightemitting diode task lamp. The problem of developing an energy efficient light emitting diode task lamp

167

Solar parabolic dish technology annual evaluation report. Fiscal year 1983  

DOE Green Energy (OSTI)

This report summarizes the activities of the JPL Solar Thermal Power Systems Parabolic Dish Project for FY 1983. Included are discussions on designs of module development including their concentrator, receiver, and power conversion subsystem together with a separate discussion of concentrator development. Analyses and test results, along with progress on field tests, Small Community Experiment system development, and tests at the Parabolic Dish Test Site are also included.

Not Available

1984-04-15T23:59:59.000Z

168

Parabolic Whittaker Functions and Topological Field Theories I  

E-Print Network (OSTI)

First, we define a generalization of the standard quantum Toda chain inspired by a construction of quantum cohomology of partial flags spaces GL(\\ell+1)/P, P a parabolic subgroup. Common eigenfunctions of the parabolic quantum Toda chains are generalized Whittaker functions given by matrix elements of infinite-dimensional representations of gl(\\ell+1). For maximal parabolic subgroups (i.e. for P such that GL(\\ell+1)/P=\\mathbb{P}^{\\ell}) we construct two different representations of the corresponding parabolic Whittaker functions as correlation functions in topological quantum field theories on a two-dimensional disk. In one case the parabolic Whittaker function is given by a correlation function in a type A equivariant topological sigma model with the target space \\mathbb{P}^{\\ell}. In the other case the same Whittaker function appears as a correlation function in a type B equivariant topological Landau-Ginzburg model related with the type A model by mirror symmetry. This note is a continuation of our project of establishing a relation between two-dimensional topological field theories (and more generally topological string theories) and Archimedean (\\infty-adic) geometry. From this perspective the existence of two, mirror dual, topological field theory representations of the parabolic Whittaker functions provide a quantum field theory realization of the local Archimedean Langlands duality for Whittaker functions. The established relation between the Archimedean Langlands duality and mirror symmetry in two-dimensional topological quantum field theories should be considered as a main result of this note.

Anton Gerasimov; Dimitri Lebedev; Sergey Oblezin

2010-02-12T23:59:59.000Z

169

Parabolic Trough Receiver Heat Loss Testing (Poster)  

DOE Green Energy (OSTI)

Parabolic trough receivers, or heat collection elements (HCEs), absorb sunlight focused by the mirrors and transfer that thermal energy to a fluid flowing within them. Thje absorbing tube of these receivers typically operates around 400 C (752 F). HCE manufacturers prevent thermal loss from the absorbing tube to the environment by using sputtered selective Cermet coatings on the absorber and by surrounding the absorber with a glass-enclosed evacuated annulus. This work quantifies the heat loss of the Solel UVAC2 and Schott PTR70 HCEs. At 400 C, the HCEs perform similarly, losing about 400 W/m of HCE length. To put this in perspective, the incident beam radiation on a 5 m mirror aperture is about 4500 W/m, with about 75% of that energy ({approx} 3400 W/m) reaching the absorber surface. Of the 3400 W/m on the absorber, about 3000 W/m is absorbed into the working fluid while 400 W/m is lost to the environment.

Price, H.; Netter, J.; Bingham, C.; Kutscher, C.; Burkholder, F.; Brandemuehl, M.

2007-03-01T23:59:59.000Z

170

Solargenix Energy Advanced Parabolic Trough Development  

SciTech Connect

The Solargenix Advanced Trough Development Project was initiated in the Year 2000 with the support of the DOE CSP Program and, more recently, with the added support of the Nevada Southwest Energy Partnership. Parabolic trough plants are the most mature solar power technology, but no large-scale plants have been built in over a decade. Given this lengthy lull in deployment, our first Project objective was development of improved trough technology for near-term deployment, closely patterned after the best of the prior-generation troughs. The second objective is to develop further improvements in next-generation trough technology that will lead to even larger reductions in the cost of the delivered energy. To date, this Project has successfully developed an advanced trough, which is being deployed on a 1-MW plant in Arizona and will soon be deployed in a 64-MW plant in Nevada. This advanced trough offers a 10% increase in performance and over an 20% decrease in cost, relative to prior-generation troughs.

Gee, R. C.; Hale, M. J.

2005-11-01T23:59:59.000Z

171

Modeling of a Parabolic Trough Solar Field for Acceptance Testing: A Case Study  

DOE Green Energy (OSTI)

As deployment of parabolic trough concentrating solar power (CSP) systems ramps up, the need for reliable and robust performance acceptance test guidelines for the solar field is also amplified. Project owners and/or EPC contractors often require extensive solar field performance testing as part of the plant commissioning process in order to ensure that actual solar field performance satisfies both technical specifications and performance guaranties between the involved parties. Performance test code work is currently underway at the National Renewable Energy Laboratory (NREL) in collaboration with the SolarPACES Task-I activity, and within the ASME PTC-52 committee. One important aspect of acceptance testing is the selection of a robust technology performance model. NREL1 has developed a detailed parabolic trough performance model within the SAM software tool. This model is capable of predicting solar field, sub-system, and component performance. It has further been modified for this work to support calculation at subhourly time steps. This paper presents the methodology and results of a case study comparing actual performance data for a parabolic trough solar field to the predicted results using the modified SAM trough model. Due to data limitations, the methodology is applied to a single collector loop, though it applies to larger subfields and entire solar fields. Special consideration is provided for the model formulation, improvements to the model formulation based on comparison with the collected data, and uncertainty associated with the measured data. Additionally, this paper identifies modeling considerations that are of particular importance in the solar field acceptance testing process and uses the model to provide preliminary recommendations regarding acceptable steady-state testing conditions at the single-loop level.

Wagner, M. J.; Mehos, M. S.; Kearney, D. W.; McMahan, A. C.

2011-01-01T23:59:59.000Z

172

Does the fully parabolic quasilinear 1D Keller-Segel system enjoy long-time asymptotics analogous to its parabolic-elliptic simplification?  

E-Print Network (OSTI)

We show that the one-dimensional fully parabolic Keller-Segel system with nonlinear diffusion possesses global-in-time solutions, provided the nonlinear diffusion is equal to (1+u)^{-\\alpha}, for \\alpha parabolic-elliptic case to the fully parabolic one. However, in the parabolic-elliptic case the above mentioned integrability condition on nonlinear diffusion sharply distinguishes between global existence and blowup cases. We are unable to recover the entire global existence counterpart of this result in a fully parabolic case.

Jan Burczak; Tomasz Cie?lak; Cristian Morales-Rodrigo

2011-11-07T23:59:59.000Z

173

Mean wind forces on parabolic-trough solar collectors  

DOE Green Energy (OSTI)

The purpose of this study was to investigate characteristics of mean wind loads produced by airflow in and around several configurations of parabolic trough solar collectors with and without a wind fence. Four basic parabolic shapes were investigated as single units and one shape was studied as part of several array fields. One 1:25 scale model of each parabolic shape was constructed for mounting on a force balance to measure two forces and three moments. The effects of several dominant variables were investigated in this study: wind-azimuth (or yaw), trough elevation (or pitch) angle, array field configuration, and protective wind fence characteristics. All measurements were made in a boundary-layer flow developed by the meteorological wind tunnel at the Fluid Dynamics and Diffusion Laboratory of Colorado State University. Results are presented and discussed. (WHK)

Peterka, J.A.; Sinau, J.M.; Cermak, J.E.

1980-05-01T23:59:59.000Z

174

Status of APS 1-Mwe Parabolic Trough Project  

SciTech Connect

Arizona Public Service (APS) is currently installing new power facilities to generate a portion of its electricity from solar resources that will satisfy its obligation under the Arizona Environmental Portfolio Standard (EPS). During FY04, APS began construction on a 1-MWe parabolic trough concentrating solar power plant. This plant represents the first parabolic trough plant to begin construction since 1991. Site preparation and construction activities continued throughout much of FY05, and startup activities are planned for Fall 2005 (with completion early in FY06). The plant will be the first commercial deployment of the Solargenix parabolic trough collector technology developed under contract to the National Renewable Energy Laboratory. The plant will use an organic Rankine cycle (ORC) power plant, provided by Ormat. The ORC power plant is much simpler than the conventional steam Rankine cycle plant and allows unattended operation of the facility.

Canada, S.; Brosseau, D.; Kolb, G.; Moore, L.; Cable, R.; Price, H.

2005-11-01T23:59:59.000Z

175

Interpretation of parabolic arcs in pulsar secondary spectra  

E-Print Network (OSTI)

Pulsar dynamic spectra sometimes show organised interference patterns; these patterns have been shown to have power spectra which often take the form of parabolic arcs, or sequences of inverted parabolic arclets whose apexes themselves follow a parabolic locus. Here we consider the interpretation of these arc and arclet features. We give a statistical formulation for the appearance of the power spectra, based on the stationary phase approximation to the Fresnel-Kirchoff integral. We present a simple analytic result for the power-spectrum expected in the case of highly elongated images, and a single-integral analytic formulation appropriate to the case of axisymmetric images. Our results are illustrated in both the ensemble-average and snapshot regimes. Highly anisotropic scattering appears to be an important ingredient in the formation of the observed arclets.

Mark Walker; Don Melrose; Dan Stinebring; Chengmin Zhang

2004-03-25T23:59:59.000Z

176

The first Chern form on moduli of parabolic bundles  

E-Print Network (OSTI)

For moduli space of stable parabolic bundles on a compact Riemann surface, we derive an explicit formula for the curvature of its canonical line bundle with respect to Quillen's metric and interpret it as a local index theorem for the family of dbar-operators in associated parabolic endomorphism bundles. The formula consists of two terms: one standard (proportional to the canonical Kaehler form on the moduli space), and one nonstandard, called a cuspidal defect, that is defined by means of special values of the Eisenstein-Maass series. The cuspidal defect is explicitly expressed through curvature forms of certain natural line bundles on the moduli space related to the parabolic structure. We also compare our result with Witten's volume computation.

Leon A. Takhtajan; Peter G. Zograf

2006-09-26T23:59:59.000Z

177

Universal estimate of the gradient for parabolic equations  

E-Print Network (OSTI)

We suggest a modification of the estimate for weighted Sobolev norms of solutions of parabolic equations such that the matrix of the higher order coefficients is included into the weight for the gradient. More precisely, we found the upper limit estimate that can be achieved by variations of the zero order coefficient. As an example of applications, an asymptotic estimate was obtained for the gradient at initial time. The constant in the estimates is the same for all possible choices of the dimension, domain, time horizon, and the coefficients of the parabolic equation. As an another example of application, existence and regularity results are obtained for parabolic equations with time delay for the gradient.

Nikolai Dokuchaev

2007-09-06T23:59:59.000Z

178

Gamma bang time/reaction history diagnostics for the National Ignition Facility using 90 deg. off-axis parabolic mirrors  

Science Conference Proceedings (OSTI)

Gas Cherenkov detectors (GCDs) have been used to convert fusion gamma into photons to achieve gamma bang time and reaction history measurements. The GCDs designed for OMEGA used Cassegrain reflector optics in order to fit inside a 10 in. manipulator. A novel design for the National Ignition Facility using 90 deg. off-axis parabolic mirrors will increase light collection efficiency from fusion gammas and achieve minimum time dispersion. The broadband Cherenkov light (from 200 to 800 nm) is relayed into a high-speed detector using three parabolic mirrors. Because light is collected from many source planes throughout the CO{sub 2} gas volume, the detector is positioned at the stop position rather than at an image position. The stop diameter and its position are independent of the light-generation location along the gas cell. The current design collects light from a 100 mm diameter by 500 mm long gas volume. Optical ray tracings demonstrate how light can be collected from different angled trajectories of the Compton electrons as they fly through the CO{sub 2} gas volume. A cluster of four channels will allow for increased dynamic range as well as for different gamma energy threshold sensitivities.

Malone, R. M. [National Security Technologies, P.O. Box 809, Los Alamos, New Mexico 87544 (United States); Herrmann, H. W.; Mack, J. M.; Young, C. S. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States); Stoeffl, W. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States)

2008-10-15T23:59:59.000Z

179

Arnold Schwarzenegger LIGHTING RESEARCH PROGRAM  

E-Print Network (OSTI)

Project Summaries ELEMENT 2: ADVANCE LIGHTING TECHNOLOGIES PROJECT 2.1 LIGHT EMITTING DIODE (LED light emitting diodes (LED) technology for general lighting applications by developing a task lamp

180

Nonlocal Operators, Parabolic-type Equations, and Ultrametric Random Walks  

E-Print Network (OSTI)

In this article we introduce a new type of nonlocal operators and study the Cauchy problem for certain parabolic-type pseudodifferential equations naturally associated to these operators. Some of these equations are the p-adic master equations of certain models of complex systems introduced by Avetisov et al. The fundamental solutions of these parabolic-type equations are transition functions of random walks on the n-dimensional vector space over the field of p-adic numbers. We study some properties of these random walks, including the first passage time.

L. F. Chacón-Cortes; W. A. Zúńiga-Galindo

2013-08-22T23:59:59.000Z

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


181

The parabolic trigonometric functions and the Chebyshev radicals  

E-Print Network (OSTI)

The parabolic trigonometric functions have recently been introduced as an intermediate step between circular and hyperbolic functions. They have been shown to be expressible in terms of irrational functions, linked to the solution of third degree algebraic equations. We show the link of the parabolic trigonometric functions with the Chebyshev radicals and also prove that further generalized forms of trigonometric functions, providing the natural solutions of the quintic algebraic equation, can be defined. We also discuss the link of this family of functions with the modular elliptic functions. 1

G. Dattoli; M. Migliorati; P. E. Ricci

2011-02-08T23:59:59.000Z

182

Natural convective studies within a compound parabolic concentrator enclosure  

SciTech Connect

The contribution due to natural convection within a compound parabolic concentrator enclosure has been experimentally determined. These studies have been conducted within a truncated compound parabolic concentrator having a concentration ratio of 4, a receiver width of 3.175 cm, and a length of 244.0 cm. The receiver was heated electrically while the aperture was provided with a duct that was cooled by water. The limbs of the collector were fabricated from aluminum. Temperatures were directly obtained with copper constantan thermocouples located throughout the entire enclosure and provided the basis needed to calculate the different modes of heat transfer. The constant heat flux

Tatara, R.A.

1983-01-01T23:59:59.000Z

183

Electromagnetic Casimir forces of parabolic cylinder and knife-edge geometries  

E-Print Network (OSTI)

An exact calculation of electromagnetic scattering from a perfectly conducting parabolic cylinder is employed to compute Casimir forces in several configurations. These include interactions between a parabolic cylinder and ...

Graham, Noah

184

SunShot Initiative: High-Concentration, Low-Cost Parabolic Trough...  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Concentration, Low-Cost Parabolic Trough System for Baseload CSP to someone by E-mail Share SunShot Initiative: High-Concentration, Low-Cost Parabolic Trough System for...

185

NREL: TroughNet - U.S. Parabolic Trough Power Plant Data  

NLE Websites -- All DOE Office Websites (Extended Search)

U.S. Parabolic Trough Power Plant Data Here you'll find data on parabolic trough power plants in operation and under development in the United States. The data include plant type,...

186

SunShot Initiative: Advanced Low-Cost Receivers for Parabolic...  

NLE Websites -- All DOE Office Websites (Extended Search)

Advanced Low-Cost Receivers for Parabolic Troughs to someone by E-mail Share SunShot Initiative: Advanced Low-Cost Receivers for Parabolic Troughs on Facebook Tweet about SunShot...

187

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER  

E-Print Network (OSTI)

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER ACOUSTICS "parabolic" equations (WAPEs) in underwater acoustics (assuming cylindrical symmetry). Existing the discretization of transparent bottom boundary conditions. In oceanography one wants to calculate the underwater

Ehrhardt, Matthias

188

Executive Summary: Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts  

DOE Green Energy (OSTI)

Sargent& Lundy LLC conducted an independent analysis of parabolic trough and power tower solar technology cost and performance.

Not Available

2003-10-01T23:59:59.000Z

189

Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts  

DOE Green Energy (OSTI)

Sargent and Lundy LLC conducted an independent analysis of parabolic trough and power tower solar technology cost and performance.

Not Available

2003-10-01T23:59:59.000Z

190

PARABOLIC BUNDLES ON ALGEBRAIC SURFACES I- THE DONALDSON–UHLENBECK COMPACTIFICATION  

E-Print Network (OSTI)

Abstract. The aim of this paper is to construct the parabolic version of the Donaldson–Uhlenbeck compactification for the moduli space of parabolic stable bundles on an algenraic surface with parabolic structures along a divisor with normal crossing singularities. We prove the non–emptiness of the moduli space of parabolic stable bundles of rank 2 and also prove the existence of components with smooth points. 1.

V. Balaji; A. Dey; R. Parthasarathi

2006-01-01T23:59:59.000Z

191

$C^{1,\\al}$ regularity of solutions to parabolic Monge-Amp\\'ere equations  

E-Print Network (OSTI)

We study interior $C^{1, \\al}$ regularity of viscosity solutions of the parabolic Monge-Amp\\'ere equation

Daskalopoulos, Panagiota

2009-01-01T23:59:59.000Z

192

BSDE driven by Dirichlet Process and Semi-linear Parabolic PDE.  

E-Print Network (OSTI)

BSDE driven by Dirichlet Process and Semi-linear Parabolic PDE. Application to Homogenization) also gives the weak solution of a semi-linear system of parabolic PDEs with a second-order divergence is associated to a divergence-form partial differential operator, and its connection with semi- linear parabolic

Paris-Sud XI, Université de

193

Operator-splitting finite element algorithms for computations of high-dimensional parabolic problems  

E-Print Network (OSTI)

Operator-splitting finite element algorithms for computations of high-dimensional parabolic t i c l e i n f o Keywords: Operator-splitting method Finite element method Parabolic equations High-dimensional problems a b s t r a c t An operator-splitting finite element method for solving high-dimensional parabolic

Ganesan, Sashikumaar

194

The parabolic Anderson model with heavy-tailed potential Peter Morters  

E-Print Network (OSTI)

The parabolic Anderson model with heavy-tailed potential Peter M¨orters Bath joint work with Remco effects can be caused by considerable irregularity of the medium? Peter M¨orters (Bath) The parabolic effects can be caused by considerable irregularity of the medium? Peter M¨orters (Bath) The parabolic

Mörters, Peter

195

ON PARABOLIC SUBGROUPS OF CLASSICAL GROUPS WITH A FINITE NUMBER OF  

E-Print Network (OSTI)

ON PARABOLIC SUBGROUPS OF CLASSICAL GROUPS WITH A FINITE NUMBER OF ORBITS ON THE UNIPOTENT RADICAL , all parabolic subgroups P of G with a finite number of orbits on the unipotent radical Pu algebraic group defined over an algebraically closed field k of characteristic 0. Let P be a parabolic

Bielefeld, University of

196

A Sparse Grid SpaceTime Discretization Scheme for Parabolic Problems  

E-Print Network (OSTI)

A Sparse Grid Space­Time Discretization Scheme for Parabolic Problems Michael Griebel, Daniel Oeltz Abstract In this paper we consider the discretization in space and time of parabolic di#erential equations. This holds in many applications due to the smoothing properties of the propagator of the parabolic PDE (heat

Bartels, Soeren

197

Parabolic equation modeling of high frequency acoustic transmission with an evolving sea surface  

E-Print Network (OSTI)

Parabolic equation modeling of high frequency acoustic transmission with an evolving sea surface J is combined with a rough surface formulation of a parabolic equation model for predicting time an approximation of the time-varying acoustic field. The wide-angle parabolic equation model manages the rough sea

Archer, Cristina Lozej

198

Convergence of Singular Limits for Multi-D Semilinear Hyperbolic Systems to Parabolic Systems  

E-Print Network (OSTI)

Convergence of Singular Limits for Multi-D Semilinear Hyperbolic Systems to Parabolic Systems systems to parabolic systems. The singular limits are studied combining Tartar's and G#19;erard of the system. Key words and phrases: Hyperbolic systems, parabolic systems, pseudodi#11;erential oper- ators

199

Parabolic Kazhdan-Lusztig R-polynomials for tight quotients of the symmetric groups 1  

E-Print Network (OSTI)

Parabolic Kazhdan-Lusztig R-polynomials for tight quotients of the symmetric groups formulas for the parabolic Kazhda* *n- Lusztig R-polynomials of the tight quotients* * to that of the Kazhdan-Lusztig polynomials. In 1987 Deodhar ([5]) introduced parabolic analogues of all

Brenti, Francesco

200

REMARKS ON THE PARABOLIC CURVES ON SURFACES AND ON THE MANYDIMENSIONAL M  

E-Print Network (OSTI)

REMARKS ON THE PARABOLIC CURVES ON SURFACES AND ON THE MANY­DIMENSIONAL M ¨ OBIUS--STURM THEORY V. I. Arnold V. A. Steklov Mathematical Institute August 26, 1997 Conjecture on Four Parabolic Curves of several variables) show that natural analogs of inflection points are parabolic curves of surfaces

Arnold, Vladimir Igorevich

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


201

Elastic parabolic equation solutions for underwater acoustic problems using seismic sources  

E-Print Network (OSTI)

Elastic parabolic equation solutions for underwater acoustic problems using seismic sources Scott D theoretic methods, and attempts to model them with fluid-bottom parabolic equation solu- tions suggest between elastic and acoustic waves, current elastic parabolic equation solutions must be modified to allow

202

Theory of Parabolic Pulse Propagation in Nonlinear Dispersion Decreasing Optical Fiber Amplifiers  

E-Print Network (OSTI)

1 Theory of Parabolic Pulse Propagation in Nonlinear Dispersion Decreasing Optical Fiber Amplifiers pulses with an initial parabolic power profile keep their shape and acquire a linear frequency chirp upon presence of linear amplification, parabolic pulses enjoy the remarkable property of representing a common

Paris-Sud XI, Université de

203

Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry and sediment thickness  

E-Print Network (OSTI)

Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry September 2007; accepted 27 September 2007 Recent improvements in the parabolic equation method are combined to extend this approach to a larger class of seismo-acoustics problems. The variable rotated parabolic

204

Parallelizing Implicit Algorithm for TimeDependent Problems by Parabolic Domain  

E-Print Network (OSTI)

Parallelizing Implicit Algorithm for Time­Dependent Problems by Parabolic Domain Decomposition parallel high­order algorithm for the solution of parabolic and elliptic PDE's. The parallelization decomposition,parabolic and elliptic PDEs, spectral method, lcoal Fourier bases,Green function, parallelization

Averbuch, Amir

205

HEART RATE AND BLOOD PRESSURE VARIABILITY UNDER MOON, MARS AND ZERO GRAVITY CONDITIONS DURING PARABOLIC FLIGHTS  

E-Print Network (OSTI)

PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1, Belgium, Email: andre.aubert@med.kuleuven.be ABSTRACT Gravity changes during partial-G parabolic flights requires the understanding of how the CVS adapts to gravity changes. Parabolic flights are one

206

HEART RATE AND BLOOD PRESSURE VARIABILITY UNDER MOON, MARS AND ZERO GRAVITY CONDITIONS DURING PARABOLIC FLIGHTS  

E-Print Network (OSTI)

PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1 Leuven, Belgium, Email: andre.aubert@med.kuleuven.be ABSTRACT Gravity changes during partial-G parabolic to reduce postflight orthostatic intolerance. Key words: parabolic flight; heart rate; blood pressure

207

Parabolic geometries and normal Weyl structures First BGG operators and special solutions  

E-Print Network (OSTI)

Parabolic geometries and normal Weyl structures First BGG operators and special solutions structures & BGG solutions #12;Parabolic geometries and normal Weyl structures First BGG operators to a parabolic geometry. The first operator in each BGG sequence defines a geometric overdetermined system

Drmota, Michael

208

Harnack Inequalities for NonNegative Solutions to Degenerate and Singular Parabolic Partial  

E-Print Network (OSTI)

Harnack Inequalities for Non­Negative Solutions to Degenerate and Singular Parabolic Partial, Local Behaviour of Solutions of Quasi­linear Parabolic Equations, Arch. Rat. Mech. Anal 25, (1967), 81 Parabolic Equations with Measurable Coefficients, Arch. Rational. Mech. Anal. 118, (1992), 257­271. [4] E

Gianazza, Ugo

209

Influence of the initial phase profile on the asymptotic self-similar parabolic dynamics  

E-Print Network (OSTI)

Influence of the initial phase profile on the asymptotic self-similar parabolic dynamics Christophe phase profile on the convergence towards asymptotic self-similar parabolic shape. More precisely, based on numerical simulations, we discuss the impact of an initial linear chirp and a phase shift. If the parabolic

Paris-Sud XI, Université de

210

ERROR ESTIMATES FOR FINITE DIFFERENCE METHODS FOR A WIDE-ANGLE `PARABOLIC' EQUATION  

E-Print Network (OSTI)

ERROR ESTIMATES FOR FINITE DIFFERENCE METHODS FOR A WIDE-ANGLE `PARABOLIC' EQUATION G. D. AKRIVIS-value problem for a third-order p.d.e., a wide-angle `parabolic' equation frequently used in underwater. wide-angle `parabolic' equation, Underwater Acoustics, finite difference error esti- mates, interface

Akrivis, Georgios

211

IMPLICIT-EXPLICIT MULTISTEP FINITE ELEMENT METHODS FOR NONLINEAR PARABOLIC PROBLEMS  

E-Print Network (OSTI)

IMPLICIT-EXPLICIT MULTISTEP FINITE ELEMENT METHODS FOR NONLINEAR PARABOLIC PROBLEMS Georgios boundary value problems for nonlinear parabolic equations. In space we discretize by finite element methods for the time discretization of a class of nonlinear parabolic problems of the form: Given T > 0 and u0 H, find

Akrivis, Georgios

212

Stability and Freezing of Waves in Nonlinear Hyperbolic-Parabolic Systems  

E-Print Network (OSTI)

Stability and Freezing of Waves in Nonlinear Hyperbolic-Parabolic Systems Jens Rottmann to the approximation of traveling waves in hyperbolic-parabolic systems such as the Hodgkin-Huxley model and the Fitz of this system. Note that (1.2) is parabolic in the u variable and (non-strictly) hyperbolic in the v variable

Moeller, Ralf

213

Velocity-jump processes with a finite number of speeds and their asymptotically parabolic nature  

E-Print Network (OSTI)

Velocity-jump processes with a finite number of speeds and their asymptotically parabolic nature-time behavior is described by a corresponding scalar diffusive equation of parabolic type, defined, alternative to the tradi- tional parabolic heat equation, which, on the contrary, mantains the inherent

Recanati, Catherine

214

Parabolic geometries and normal Weyl structures First BGG operators and special solutions  

E-Print Network (OSTI)

Parabolic geometries and normal Weyl structures First BGG operators and special solutions structures & BGG solutions #12;Parabolic geometries and normal Weyl structures First BGG operators the machinery of BGG sequences. Andreas Cap Weyl structures & BGG solutions #12;Parabolic geometries and normal

Drmota, Michael

215

Two parabolic equations for propagation in layered poro-elastic media  

E-Print Network (OSTI)

Two parabolic equations for propagation in layered poro-elastic media Adam M. Metzlera) Applied 10 October 2012; revised 26 March 2013; accepted 9 May 2013) Parabolic equation methods for fluid. A previous parabolic equation solution for one model of range-independent poro-elastic media [Collins et al

216

Parabolic laws of the surrounded-atom model from ab initio calculations on clusters  

E-Print Network (OSTI)

121 Parabolic laws of the surrounded-atom model from ab initio calculations on clusters A alloys, via parabolic laws which are functions of the local concentration. In this paper, using ab initio MO-CI calculations on clusters, we have shown that these parabolic laws have a microscopic electronic

Paris-Sud XI, Université de

217

Parabolic lines and caustics in weakly anisotropic solids 9iFODY##9DYU\\XN  

E-Print Network (OSTI)

117 Parabolic lines and caustics in weakly anisotropic solids 9iFODY##9DYU\\ĂľXN *HRSK@ig.cas.cz Summary The behaviour of parabolic lines and caustics in anisotropic solids can be, in general, very, no parabolic lines appear on the S1 slowness sheet. Consequently, the S1 wave sheet displays no caustics

Cerveny, Vlastislav

218

Self-accelerating parabolic beams in quadratic nonlinear media Ido Dolev, Ana Libster, and Ady Arie  

E-Print Network (OSTI)

Self-accelerating parabolic beams in quadratic nonlinear media Ido Dolev, Ana Libster, and Ady Arie://apl.aip.org/authors #12;Self-accelerating parabolic beams in quadratic nonlinear media Ido Dolev,a) Ana Libster, and Ady present experimental observation of self-accelerating parabolic beams in quadratic nonlinear media. We

Arie, Ady

219

Repeated games for eikonal equations, integral curvature flows and non-linear parabolic  

E-Print Network (OSTI)

Repeated games for eikonal equations, integral curvature flows and non-linear parabolic integro works of Kohn and the second author (2006 and 2009): general fully non-linear parabolic integro- surfaces. For parabolic integro-differential equations, players choose smooth functions on the whole space

Paris-Sud XI, Université de

220

Flux Distribution of a Single-Axis Tracking Parabolic Trough Array with Photovoltaic Receiver  

E-Print Network (OSTI)

Flux Distribution of a Single-Axis Tracking Parabolic Trough Array with Photovoltaic Receiver G 0200 Australia E-mail: gregory.burgess@anu.edu.au Abstract Single-axis tracking parabolic troughs Long arrays of single-axis tracking parabolic troughs with a fluid filled absorber are a well

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


221

Parabolic Trough Solar Power for Competitive U.S. Markets  

DOE Green Energy (OSTI)

Nine parabolic trough power plants located in the California Mojave Desert represent the only commercial development of large-scale solar power plants to date. Although all nine plants continue to operate today, no new solar power plants have been completed since 1990. Over the last several years, the parabolic trough industry has focused much of its efforts on international market opportunities. Although the power market in developing countries appears to offer a number of opportunities for parabolic trough technologies due to high growth and the availability of special financial incentives for renewables, these markets are also plagued with many difficulties for developers. In recent years, there has been some renewed interest in the U.S. domestic power market as a result of an emerging green market and green pricing incentives. Unfortunately, many of these market opportunities and incentives focus on smaller, more modular technologies (such as photovoltaics or wind power), and as a result they tend to exclude or are of minimum long-term benefit to large-scale concentrating solar power technologies. This paper looks at what is necessary for large-scale parabolic trough solar power plants to compete with state-of-the-art fossil power technology in a competitive U.S. power market.

Henry W. Price

1998-11-01T23:59:59.000Z

222

The Nonlinear Evolution of Disturbances to a Parabolic Jet  

Science Conference Proceedings (OSTI)

It has been shown that the linearized equations for disturbances to a parabolic jet on a ? plane, with curvature Un0(y) such that the basic-state absolute vorticity gradient ? ? Un0(y) is zero, ultimately become inconsistent in the neighborhood ...

G. Brunet; P. H. Haynes

1995-02-01T23:59:59.000Z

223

Theoretical Investigation of the Closed Type Parabolic Trough  

Science Conference Proceedings (OSTI)

Of a closed type parabolic trough solar collector, the thermal performance was analyzed, and a mathematical model was proposed, and experience system was built. As well mathematical model was validated with the measure data. Keywords: trough solar power, collector, numerical simulation, thermal analysis

Zhong-Zhu Qiu; Qiming Li; Peng Li; Yi Zhang; Jia He; Wenwen Guo

2012-07-01T23:59:59.000Z

224

Compound parabolic concentrator with cavity for tubular absorbers  

DOE Patents (OSTI)

A compond parabolic concentrator with a V-shaped cavity is provided in which an optical receiver is emplaced. The cavity redirects all energy entering between the receiver and the cavity structure onto the receiver, if the optical receiver is emplaced a distance from the cavity not greater than 0.27 r (where r is the radius of the receiver).

Winston, Roland (5217C S. University Ave., Chicago, IL 60615)

1983-01-01T23:59:59.000Z

225

Long-term average performance benefits of parabolic trough improvements  

DOE Green Energy (OSTI)

Improved parabolic trough concentrating collectors will result from better design, improved fabrication techniques, and the development and utilization of improved materials. The difficulty of achieving these improvements varies as does their potential for increasing parabolic trough performance. The purpose of this analysis is to quantify the relative merit of various technology advancements in improving the long-term average performance of parabolic trough concentrating collectors. The performance benefits of improvements are determined as a function of operating temperature for north-south, east-west, and polar mounted parabolic troughs. The results are presented graphically to allow a quick determination of the performance merits of particular improvements. Substantial annual energy gains are shown to be attainable. Of the improvements evaluated, the development of stable back-silvered glass reflective surfaces offers the largest performance gain for operating temperatures below 150/sup 0/C. Above 150/sup 0/C, the development of trough receivers that can maintain a vacuum is the most significant potential improvement. The reduction of concentrator slope errors also has a substantial performance benefit at high operating temperatures.

Gee, R.; Gaul, H.W.; Kearney, D.; Rabl, A.

1980-03-01T23:59:59.000Z

226

PARABOLIC TROUGH SOLAR POWER FOR COMPETITIVE U.S. MARKETS  

E-Print Network (OSTI)

Nine parabolic trough power plants located in the California Mojave Desert represent the only commercial development of large-scale solar power plants to date. Although all nine plants continue to operate today, no new solar power plants have been completed since 1990. Over the last several years, the parabolic trough industry has focused much of its efforts on international market opportunities. Although the power market in developing countries appears to offer a number of opportunities for parabolic trough technologies due to high growth and the availability of special financial incentives for renewables, these markets are also plagued with many difficulties for developers. In recent years, there has been some renewed interest in the U.S. domestic power market as a result of an emerging green market and green pricing incentives. Unfortunately, many of these market opportunities and incentives focus on smaller, more modular technologies (such as photovoltaics or wind power), and as a result they tend to exclude or are of minimum long-term benefit to large-scale concentrating solar power technologies. This paper looks at what is necessary for large-scale parabolic trough solar power plants to compete with state-of-the-art fossil power technology in a competitive U.S. power market.

Henry W. Price; Maui Hawaii; Henry W. Price; Rainer Kistner

1998-01-01T23:59:59.000Z

227

Secondary concentrators for parabolic dish solar thermal power systems  

SciTech Connect

One approach to production of electricity or high-temperature process heat from solar energy is to use point-focusing, two-axis pointing concentrators in a distributed-receiver solar thermal system. This paper discusses some of the possibilities and problems in using compound concentrators in parabolic dish systems. 18 refs.

Jaffe, L.D.; Poon, P.T.

1981-01-01T23:59:59.000Z

228

Lighting Group: Links  

NLE Websites -- All DOE Office Websites (Extended Search)

Links Links Links Organizations Illuminating Engineering Society of North America (IESNA) International Commission on Illumination (CIE) International Association of Lighting Designers (IALD) International Association of Energy-Efficient Lighting Lightfair International Energy Agency - Task 21: Daylight in Buildings: Design Tools and Performance Analysis International Energy Agency - Task 31: Daylighting Buildings in 21st Century National Association on Qualifications for the Lighting Professions (NCQLP) National Association of Independent Lighting Distributors (NAILD) International Association of Lighting Management Companies (NALMCO) Research Centers California Lighting Technology Center Lighting Research Center Lighting Research at Canada Institute for Research in Construction

229

Integrated LED-based luminare for general lighting  

DOE Patents (OSTI)

Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.

2013-03-05T23:59:59.000Z

230

Electromagnetic Casimir Forces of Parabolic Cylinder and Knife-Edge Geometries  

E-Print Network (OSTI)

An exact calculation of electromagnetic scattering from a perfectly conducting parabolic cylinder is employed to compute Casimir forces in several configurations. These include interactions between a parabolic cylinder and a plane, two parabolic cylinders, and a parabolic cylinder and an ordinary cylinder. To elucidate the effect of boundaries, special attention is focused on the "knife-edge" limit in which the parabolic cylinder becomes a half-plane. Geometrical effects are illustrated by considering arbitrary rotations of a parabolic cylinder around its focal axis, and arbitrary translations perpendicular to this axis. A quite different geometrical arrangement is explored for the case of an ordinary cylinder placed in the interior of a parabolic cylinder. All of these results extend simply to nonzero temperatures.

Noah Graham; Alexander Shpunt; Thorsten Emig; Sahand Jamal Rahi; Robert L. Jaffe; Mehran Kardar

2011-03-30T23:59:59.000Z

231

Electromagnetic Casimir forces of parabolic cylinder and knife-edge geometries  

SciTech Connect

An exact calculation of electromagnetic scattering from a perfectly conducting parabolic cylinder is employed to compute Casimir forces in several configurations. These include interactions between a parabolic cylinder and a plane, two parabolic cylinders, and a parabolic cylinder and an ordinary cylinder. To elucidate the effect of boundaries, special attention is focused on the 'knife-edge' limit in which the parabolic cylinder becomes a half-plane. Geometrical effects are illustrated by considering arbitrary rotations of a parabolic cylinder around its focal axis, and arbitrary translations perpendicular to this axis. A quite different geometrical arrangement is explored for the case of an ordinary cylinder placed in the interior of a parabolic cylinder. All of these results extend simply to nonzero temperatures.

Graham, Noah [Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States); Shpunt, Alexander; Kardar, Mehran [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Emig, Thorsten [Laboratoire de Physique Theorique et Modeles Statistiques, CNRS UMR 8626, Bat. 100, Universite Paris-Sud, 91405 Orsay cedex (France); Rahi, Sahand Jamal [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Street, New York, New York 10065 (United States); Jaffe, Robert L. [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Center for Theoretical Physics and Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-06-15T23:59:59.000Z

232

Global Assessment of Hydrogen Technologies - Task 2 Report Comparison of Performance and Emissions from Near-Term Hydrogen Fueled Light Duty Vehicles  

Science Conference Proceedings (OSTI)

An investigation was conducted on the emissions and efficiency from hydrogen blended compressed natural gas (CNG) in light duty vehicles. The different blends used in this investigation were 0%, 15%, 30%, 50%, 80%, 95%, and ~100% hydrogen, the remainder being compressed natural gas. The blends were tested using a Ford F-150 and a Chevrolet Silverado truck supplied by Arizona Public Services. Tests on emissions were performed using four different driving condition tests. Previous investigation by Don Karner and James Frankfort on a similar Ford F-150 using a 30% hydrogen blend showed that there was substantial reduction when compared to gasoline in carbon monoxide (CO), nitrogen oxide (NOx), and carbon dioxide (CO2) emissions while the reduction in hydrocarbon (HC) emissions was minimal. This investigation was performed using different blends of CNG and hydrogen to evaluate the emissions reducing capabilities associated with the use of the different fuel blends. The results were then tested statistically to confirm or reject the hypotheses on the emission reduction capabilities. Statistically analysis was performed on the test results to determine whether hydrogen concentration in the HCNG had any effect on the emissions and the fuel efficiency. It was found that emissions from hydrogen blended compressed natural gas were a function of driving condition employed. Emissions were found to be dependent on the concentration of hydrogen in the compressed natural gas fuel blend.

Fouad, Fouad H.; Peters, Robert W.; Sisiopiku, Virginia P.; Sullivan Andrew J.; Ng, Henry K.; Waller, Thomas

2007-12-01T23:59:59.000Z

233

Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint  

DOE Green Energy (OSTI)

As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.

Stynes, J. K.; Ihas, B.

2012-04-01T23:59:59.000Z

234

A Linear Parabolic Trough Solar Collector Performance Model  

E-Print Network (OSTI)

A performance model has been programmed for solar thermal collector based on a linear, tracking parabolic trough reflector focused on a surface-treated metallic pipe receiver enclosed in an evacuated transparent tube: a Parabolic Trough Solar Collector (PTSC). This steady state, single dimensional model comprises the fundamental radiative and convective heat transfer and mass and energy balance relations programmed in the Engineering Equation Solver, EES. It considers the effects of solar intensity and incident angle, collector dimensions, material properties, fluid properties, ambient conditions, and operating conditions on the performance of the collector: the PTSC. Typical performance calculations show that when hot-water at 165C flows through a 6m by 2.3m PTSC with 900 w/m^2 solar insulation and 0 incident angle, the estimated collector efficiency is about 55% The model predictions will be confirmed by the operation of PTSCs now being installed at Carnegie Mellon.

Qu, M.; Archer, D.; Masson, S.

2006-01-01T23:59:59.000Z

235

Parabolic Trough Solar Power Plant Simulation Model: Preprint  

DOE Green Energy (OSTI)

As interest for clean renewable electric power technologies grows, a number of parabolic trough power plants of various configurations are being considered for deployment around the globe. It is essential that plant designs be optimized for each specific application. The optimum design must consider the capital cost, operations and maintenance cost, annual generation, financial requirements, and time-of-use value of the power generated. Developers require the tools for evaluating tradeoffs between these various project elements. This paper provides an overview of a computer model that is being used by scientists and developers to evaluate the tradeoff between cost, performance, and economic parameters for parabolic trough solar power plant technologies. An example is included that shows how this model has been used for a thermal storage design optimization.

Price, H.

2003-01-01T23:59:59.000Z

236

Parabolic Trouogh Optical Characterization at the National Renewable Energy Laboratory  

DOE Green Energy (OSTI)

Solar parabolic trough power plant projects are soon to be implemented in the United States and internationally. In addition to these new projects, parabolic trough power plants totaling approximately 350 MW already exist within the United States and have operated for close to 20 years. As such, the status of the technology exists within several different phases. Theses phases include R&D, manufacturing and installation, and operations and maintenance. One aspect of successful deployment of this technology is achieving and maintaining optical performance. Different optical tools are needed to assist in improving initial designs, provide quality control during manufacture and assembly, and help maintain performance during operation. This paper discusses several such tools developed at SunLab (a joint project of the National Renewable Laboratory and Sandia National Laboratories) for these purposes. Preliminary testing results are presented. Finally, plans for further tool development are discussed.

Wendelin, T. J.

2005-01-01T23:59:59.000Z

237

Parabolic-Dish Solar Concentrators of Film on Foam  

E-Print Network (OSTI)

Parabolic and spherical mirrors are constructed of aluminized PET polyester film on urethane foam. During construction, the chosen shape of the mirror is created by manipulating the elastic/plastic behavior of the film with air pressure. Foam is then applied to the film and, once hardened, air pressure is removed. At an f-number of 0.68, preliminary models have an optical angular spread of less than 0.25 degrees, a factor of 3.3 smaller than that for a perfectly spherical mirror. The possibility exists for creating large-lightweight mirrors with excellent shape and stiffness. These "film-on-foam" construction techniques may also be applicable to parabolic-trough solar concentrators but do not appear to be suitable for optical imaging applications because of irregularities in the film.

Barton, Sean A

2009-01-01T23:59:59.000Z

238

Gas Turbine/Solar Parabolic Trough Hybrid Designs: Preprint  

DOE Green Energy (OSTI)

A strength of parabolic trough concentrating solar power (CSP) plants is the ability to provide reliable power by incorporating either thermal energy storage or backup heat from fossil fuels. Yet these benefits have not been fully realized because thermal energy storage remains expensive at trough operating temperatures and gas usage in CSP plants is less efficient than in dedicated combined cycle plants. For example, while a modern combined cycle plant can achieve an overall efficiency in excess of 55%; auxiliary heaters in a parabolic trough plant convert gas to electricity at below 40%. Thus, one can argue the more effective use of natural gas is in a combined cycle plant, not as backup to a CSP plant. Integrated solar combined cycle (ISCC) systems avoid this pitfall by injecting solar steam into the fossil power cycle; however, these designs are limited to about 10% total solar enhancement. Without reliable, cost-effective energy storage or backup power, renewable sources will struggle to achieve a high penetration in the electric grid. This paper describes a novel gas turbine / parabolic trough hybrid design that combines solar contribution of 57% and higher with gas heat rates that rival that for combined cycle natural gas plants. The design integrates proven solar and fossil technologies, thereby offering high reliability and low financial risk while promoting deployment of solar thermal power.

Turchi, C. S.; Ma, Z.; Erbes, M.

2011-03-01T23:59:59.000Z

239

Development and testing of Parabolic Dish Concentrator No. 1  

DOE Green Energy (OSTI)

Parabolic Dish Concentrator No. 1 (PDC-1) is a 12-m-diameter prototype concentrator that evolved from a six-year effort to produce a unit with low life-cycle costs for use with thermal-to-electric energy conversion devices. The concentrator assembly features panels made of a resin transfer molded balsa core/fiberglass sandwich with plastic reflective film as the reflective surface and a ribbed framework to hold the panels in place. The concentrator assembly tracks in azimuth and elevation on a base frame riding on a circular track. In 1982, PDC-1 was installed at the Jet Propulsion Laboratory's Parabolic Dish Test Site at Edwards Air Force Base, California. Initial optical testing showed that the panels did not exhibit the proper parabolic contour. After reassembly to correct this problem, further optical testing discovered thermal gradients in the panels with daily temperature changes. In spite of this, PDC-1 has sufficient optical quality to operate satisfactorily in a dish-electric system. With suggested improvements, its performance could be increased. The PDC-1 development effort provided the impetus for creating innovative optical testing methods and also provided valuable information for use in designing and fabricating concentrators of future dish-electric systems.

Dennison, E.W.; Thostesen, T.O.

1984-12-15T23:59:59.000Z

240

Irrigation market for solar-thermal parabolic-dish systems  

Science Conference Proceedings (OSTI)

The potential size of the onfarm-pumped irrigation market for solar thermal parabolic dish systems in seven high-insolation states is estimated. The study is restricted to the displacement of three specific fuels: gasoline, diesel and natural gas. A model was developed to estimate the optimal number of parabolic dish modules per farm based on the minimum cost mix of conventional and solar thermal energy required to meet irrigation needs. Results indicate that the near-term market for such systems depends not only on the type of crop and method of irrigation, but also on the optimal utilization of each added module, which in turn depends on the price of conventional fuel, real discount rate, marginal cost of the solar thermal power system, local insolation level and parabolic dish system efficiency. The study concludes that the potential market size for onfarm-pumped irrigation applications ranges from 101,000 modules when a 14% real discount rate is assumed to 220,000 modules when the real discount rate drops to 8%. Arizona, Kansas, Nebraska, New Mexico and Texas account for 98% of the total demand for this application, with the natural gas replacement market accounting for the largest segment (71%) of the total market.

Habib-agahi, H.; Jones, S.C.

1981-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "task lighting parabolic" from the National Library of EnergyBeta (NLEBeta).
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241

Parabolic-Trough Technology Roadmap: A Pathway for Sustained Commercial Development and Deployment of Parabolic-Trough Technology  

DOE Green Energy (OSTI)

Technology roadmapping is a needs-driven technology planning process to help identify, select, and develop technology alternatives to satisfy a set of market needs. The DOE's Office of Power Technologies' Concentrating Solar Power (CSP) Program recently sponsored a technology roadmapping workshop for parabolic trough technology. The workshop was attended by an impressive cross section of industry and research experts. The goals of the workshop were to evaluate the market potential for trough power projects, develop a better understanding of the current state of the technology, and to develop a conceptual plan for advancing the state of parabolic trough technology. This report documents and extends the roadmap that was conceptually developed during the workshop.

Price, H.; Kearney, D.

1999-01-31T23:59:59.000Z

242

On the use of the parabolic concentration profile assumption for a rotary desiccant dehumidifier  

SciTech Connect

The current work describes a model for a desiccant dehumidifier which uses a parabolic concentration profile assumption to model the diffusion resistance inside the desiccant particle. The relative merits of the parabolic concentration profile model compared with widely utilized rotary desiccant wheel models are discussed. The periodic steady-state parabolic concentration profile model developed is efficient and can accommodate a variety of materials. These features make it an excellent tool for design studies requiring repetitive desiccant wheel simulations. A quartic concentration profile assumption was also investigated which yielded a 2.8 percent average improvement in prediction error over the parabolic model.

Chant, E.E. [Univ. of Turabo, Gurabo (Puerto Rico); Jeter, S.M. [Georgia Inst. of Technology, Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering

1995-02-01T23:59:59.000Z

243

Video Scanning Hartmann Optical Testing of State-of-the-Art Parabolic Trough Concentrators: Preprint  

DOE Green Energy (OSTI)

This paper describes the Video Scanning Hartmann Optical Test System (VSHOT) used to optically test parabolic trough designs by both Solargenix and Industrial Solar Technology.

Wendelin, T.; May, K.; Gee, R.

2006-06-01T23:59:59.000Z

244

Deformation of a thin, elastic plate to a deep parabolic cylinder  

DOE Green Energy (OSTI)

Equations governing the elastic deformation of thin plates through large displacements to deep parabolic cylinders are presented and solved. The solution consists of expressions for a spatially distributed surface pressure and uniform rim loads which, when applied to the plate, produce the specified, deep parabolic cylindrical shape. These forming loads are written in dimensionless form for parabolic cylinders of arbitrary focal length and arbitrary rim to rim aperture. Numerical results are presented and limiting values are discussed. The solution and results find immediate application to mechanical forming and adhesive retention of parabolic solar collector components.

Reuter, R.C. Jr.; Wilson, R.K.

1982-02-01T23:59:59.000Z

245

NaNO3-KNO3 Ternary Molten Salts for Parabolic Trough  

Science Conference Proceedings (OSTI)

Presentation Title, Thermodynamic Properties of Novel Low Melting Point LiNO3- NaNO3-KNO3 Ternary Molten Salts for Parabolic Trough Solar Power ...

246

Two-tank indirect thermal storage designs for solar parabolic trough power plants.  

E-Print Network (OSTI)

??The performance of a solar thermal parabolic trough plant with thermal storage is dependent upon the arrangement of the heat exchangers that ultimately transfer energy… (more)

Kopp, Joseph E.

2009-01-01T23:59:59.000Z

247

Mechanical development of the actuation system of a parabolic solar trough.  

E-Print Network (OSTI)

??This thesis documents my personal contribution to the engineering and design of an actuation system with the purpose of rotating a parabolic solar trough to… (more)

O'Rourke, Conor R. (Conor Rakis)

2011-01-01T23:59:59.000Z

248

Technical and economic analysis of parabolic trough concentrating solar thermal power plant.  

E-Print Network (OSTI)

??Includes abstract. This thesis reports on the technical and economic analysis of wet and dry cooling technologies of parabolic trough CSTP plant. This was done… (more)

Kariuki, Kibaara Samuel .

2012-01-01T23:59:59.000Z

249

Parabolic Trough Solar System Piping Model: Final Report, 13 May 2002 ? 31 December 2004  

DOE Green Energy (OSTI)

Subcontract report by Nexant, Inc., and Kearny and Associates regarding a study of a piping model for a solar parabolic trough system.

Kelly, B.; Kearney, D.

2006-07-01T23:59:59.000Z

250

Parabolic trough collector systems for thermal enhanced oil recovery  

SciTech Connect

Enhanced Oil Recovery (EOR) techniques offer a means of increasing US oil production by recovering oil otherwise unavailable when using primary or secondary production methods. The use of parabolic trough collector solar energy systems can expand the production of oil recovered by the most prevalent of these techniques, thermal EOR, by improving the economics and lessening the environmental impacts. These collector systems, their state of development, their application to EOR, and their capacity for expanding oil production are reviewed. An economic analysis which shows that these systems will meet investment hurdle rates today is also presented.

Niemeyer, W.A.; Youngblood, S.B.; Price, A.L.

1981-01-01T23:59:59.000Z

251

Inhomogeneous parabolic equations on unbounded metric measure spaces  

E-Print Network (OSTI)

We study inhomogeneous semilinear parabolic equations with source term f independent of time u_{t}={\\Delta}u+u^{p}+f(x) on a metric measure space, subject to the conditions that f(x)\\geq 0 and u(0,x)=\\phi(x)\\geq 0. By establishing Harnack-type inequalities in time t and some powerful estimates, we give sufficient conditions for non-existence, local existence, and global existence of weak solutions. This paper generalizes previous results on Euclidean spaces to general metric measure spaces.

Kenneth J. Falconer; Jiaxin Hu; Yuhua Sun

2011-03-29T23:59:59.000Z

252

Gamma Bang Time/Reaction History Diagnostics for the National Ignition Facility (NIF) Using 90-degree Off-axis Parabolic Mirrors  

SciTech Connect

Gas Cherenkov detectors (GCD) have been used to convert fusion gamma into photons to achieve gamma bang time (GBT) and reaction history measurements. The GCD designed for Omega used Cassegrain reflector optics in order to fit inside a 10-inch manipulator. A novel design for the National Ignition Facility (NIF) using 90ş off-axis parabolic (OAP) mirrors will increase light collection efficiency from fusion gammas and achieve minimum time dispersion. The broadband Cherenkov light (from 200 to 800 nm) is relayed into a high-speed detector using three parabolic mirrors. Because light is collected from many source planes throughout the CO2 gas volume, the detector is positioned at the stop position rather than an image position. The stop diameter and its position are independent of the light-generation location along the gas cell. The current design collects light from a 100-mm-diameter by 500-mm-long gas volume. Optical ray tracings demonstrate how light can be collected from different angled trajectories of the Compton electrons as they fly through the CO2 gas volume. A cluster of four channels will allow for increased dynamic range, as well as different gamma energy threshold sensitivities.

R.M. Malone, H.W. Herrmann, J.M. Mack, C.S. Young, W. Stoeffl

2008-10-01T23:59:59.000Z

253

Gamma Bang Time/Reaction History Diagnostics for the National Ignition Facility (NIF) Using 90-degree Off-axis Parabolic Mirrors  

SciTech Connect

Gas Cherenkov detectors (GCD) have been used to convert fusion gamma into photons to achieve gamma bang time (GBT) and reaction history measurements. The GCD designed for Omega used Cassegrain reflector optics in order to fit inside a ten-inch manipulator. A novel design for the National Ignition Facility (NIF) using 90ş Off-Axis Parabolic (OAP) mirrors will increase light collection efficiency from fusion gammas and achieve minimum time dispersion. The broadband Cherenkov light (from 200 to 800 nm) is relayed into a high-speed detector using three parabolic mirrors. Because light is collected from many source planes throughout the CO2 gas volume, the detector is positioned at the stop position rather than an image position. The stop diameter and its position are independent of the light-generation location along the gas cell. The current design collects light from a 100-mm diameter by 500-mm-long gas volume. Optical ray tracings demonstrate how light can be collected from different angled trajectories of the Compton electrons as they fly through the CO2 gas volume. A cluster of four channels will allow for increased dynamic range as well as different gamma energy threshold sensitivities. 52.70.La, 29.40.Ka, 42.15.Eq, 07.60.-j, 07.85.-m

H.W. Herrmann, R.M. Malone, W. Stoeffl, J.M. Mack, C.S. Young

2008-06-01T23:59:59.000Z

254

Solid-state laser pumping with a planar compound parabolic concentrator  

Science Conference Proceedings (OSTI)

A novel solid-state laser-pumping scheme is proposed that combines a reflective lamp chamber and a compound parabolic concentrator (CPC) as a light guide. The CPC is made of a transparent material of high refractive index, and light is guided by the total internal reflection, with drastically reduced reflection losses. Material is chosen so that the absorption losses are minimized in the pumping wavelength range. The lamp chamber is designed with the principles of nonimaging optics, which ensures that the radiation is efficiently transferred from the lamp to the input aperture of the CPC. The pumping efficiency was first estimated theoretically, which gave us enough justification for the more accurate calculations with ray tracing. Single as well as multiple pumping cavities are discussed. New pumping geometry results in significantly increased pumping efficiency compared with conventional geometries. Also the lamp and the laser rod are separated, leading to reduced thermal load. We found that the proposed pumping method is also applicable to diode-pumped lasers. {copyright} 1997 Optical Society of America

Pantelic, D.V.; Panic, B.M.; Belic, I.Z. [Institute of Physics, Pregrevica 118, Zemun, 11080 Belgrade (Yugoslavia)

1997-10-01T23:59:59.000Z

255

Theory of Parabolic Arcs in Interstellar Scintillation Spectra  

E-Print Network (OSTI)

Our theory relates the secondary spectrum, the 2D power spectrum of the radio dynamic spectrum, to the scattered pulsar image in a thin scattering screen geometry. Recently discovered parabolic arcs in secondary spectra are generic features for media that scatter radiation at angles much larger than the rms scattering angle. Each point in the secondary spectrum maps particular values of differential arrival-time delay and fringe rate (or differential Doppler frequency) between pairs of components in the scattered image. Arcs correspond to a parabolic relation between these quantities through their common dependence on the angle of arrival of scattered components. Arcs appear even without consideration of the dispersive nature of the plasma. Arcs are more prominent in media with negligible inner scale and with shallow wavenumber spectra, such as the Kolmogorov spectrum, and when the scattered image is elongated along the velocity direction. The arc phenomenon can be used, therefore, to constrain the inner scale and the anisotropy of scattering irregularities for directions to nearby pulsars. Arcs are truncated by finite source size and thus provide sub micro arc sec resolution for probing emission regions in pulsars and compact active galactic nuclei. Multiple arcs sometimes seen signify two or more discrete scattering screens along the propagation path, and small arclets oriented oppositely to the main arc persisting for long durations indicate the occurrence of long-term multiple images from the scattering screen.

James M. Cordes; Barney J. Rickett; Daniel R. Stinebring; William A. Coles

2004-07-03T23:59:59.000Z

256

The Piecewise Parabolic Method for Multidimensional Relativistic Fluid Dynamics  

E-Print Network (OSTI)

We present an extension of the Piecewise Parabolic Method to special relativistic fluid dynamics in multidimensions. The scheme is conservative, dimensionally unsplit, and suitable for a general equation of state. Temporal evolution is second-order accurate and employs characteristic projection operators; spatial interpolation is piece-wise parabolic making the scheme third-order accurate in smooth regions of the flow away from discontinuities. The algorithm is written for a general system of orthogonal curvilinear coordinates and can be used for computations in non-cartesian geometries. A non-linear iterative Riemann solver based on the two-shock approximation is used in flux calculation. In this approximation, an initial discontinuity decays into a set of discontinuous waves only implying that, in particular, rarefaction waves are treated as flow discontinuities. We also present a new and simple equation of state which approximates the exact result for the relativistic perfect gas with high accuracy. The strength of the new method is demonstrated in a series of numerical tests and more complex simulations in one, two and three dimensions.

A. Mignone; T. Plewa; G. Bodo

2005-05-10T23:59:59.000Z

257

Development effort of sheet molding compound (SMC) parabolic trough panels  

SciTech Connect

The objectives of the development effort are to: investigate the problems of molding parabolic trough solar reflector panels of sheet molding compound (SMC); develop molding techniques and processes by which silvered glass reflector sheets can be integrally molded into SMC trough panels; provide representative prototype panels for evaluation; and provide information regarding the technical feasibility of molding SMC panels in high volume production. The approach taken to meet the objectives was to design the parabolic panel, fabricate a prototype die, choose an SMC formulation and mold the glass and SMC together into a vertex to rim mirrored panel. The main thrust of the program was to successfully co-mold a mirrored glass sheet with the SMC. Results indicate that mirrored glass sheets, if properly strengthened to withstand the temperature and pressure of the molding process, can be successfully molded with SMC in a single press stroke using standard compression molding techniques. The finalized design of the trough panel is given. The SMC formulation chosen is a low shrink, low profile SMC using 40% by weight one inch chopped glass fibers in a uv stabilized polyester resin matrix. A program to test for the adhesion between mirrored glass sheets and the SMC is discussed briefly. (LEW)

Kirsch, P.A.; Champion, R.L.

1982-01-01T23:59:59.000Z

258

The solvability of the first initial-boundary problem for parabolic and degenerate parabolic equations in domains with a conical point  

SciTech Connect

The first initial-boundary problem for second-order parabolic and degenerate parabolic equations is investigated in a domain with a conical or angular point. The means of attack is already known and uses weighted classes of smooth or integrable functions. Sufficient conditions for a unique solution to exist and for coercive estimates for the solution to be obtained are formulated in terms of the angular measure of the solid angle and the exponent of the weight. It is also shown that if these conditions fail to hold, then the parabolic problem has elliptic properties, that is, it can have a nonzero kernel or can be nonsolvable, and, in the latter case, it is not even a Fredholm problem. A parabolic equation and an equation with some degeneracy or a singularity at a conical point are considered. Bibliography: 49 titles.

Degtyarev, Sergey P [Institute of Applied Mathematics and Mechanics, Ukraine National Academy of Sciences, Donetsk (Ukraine)

2010-09-02T23:59:59.000Z

259

BETTI NUMBERS OF PARABOLIC U(2, 1)-HIGGS BUNDLES MODULI SPACES.  

E-Print Network (OSTI)

Abstract. Let X be a compact Riemann surface together with a finite set of marked points. We use Morse theoretic techniques to compute the Betti numbers of the parabolic U(2, 1)-Higgs bundles moduli spaces over X. We give examples for one marked point showing that the Poincaré polynomials depend on the system of weights of the parabolic bundle. 1.

Marina Logares

2006-01-01T23:59:59.000Z

260

A Parallel Scheme of the Split-Step Fourier Transform Method for Solving Parabolic Wave Equation  

Science Conference Proceedings (OSTI)

The split-step Fourier transform method for solving the parabolic wave equation is briefly introduced in this paper. To achieve the acceleration of the calculation process, a parallel scheme based on matrix transpose is proposed. Due to some ingenious ... Keywords: Parabolic Wave Equation, Split-Step Fourier Transform Method, Parallel Computing

Liu Shuai; Li Zhi

2012-10-01T23:59:59.000Z

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


261

The parabolic trough power plants Andasol 1 to 3 The largest solar power plants in the world  

E-Print Network (OSTI)

The parabolic trough power plants Andasol 1 to 3 The largest solar power plants in the world and solar-thermal power plants The first parabolic trough power plants in Europe ­ the world's largest solar

Laughlin, Robert B.

262

New Light Sources for Tomorrow's Lighting Designs  

E-Print Network (OSTI)

The lighting industry is driven to provide light sources and lighting systems that, when properly applied, will produce a suitable luminous environment in which to perform a specified task. Tasks may include everything from office work, manufacturing and inspection to viewing priceless art objects, selecting the right chair for your living room, and deciding which produce item to select for tonight's dinner. While energy efficiency is a major consideration in any new lighting system design, the sacrifice of lighting quality may cost more in terms of lost productivity and user dissatisfaction than can ever be saved on that monthly energy bill. During the past several years, many new light sources have been developed and introduced. These product introductions have not been limited to anyone lamp type, but instead may be found in filament, fluorescent and high intensity discharge lamp families. Manufacturers of light sources have two basic goals for new product development. These goals are high efficiency lighting and improved color rendering properties. High efficiency lighting may take the form of either increasing lamp efficiency (lumens of light delivered per watt of power consumed) or decreasing lamp size, thus making a more easily controlled light source that places light where it is needed. The manufacturer's second goal is to produce lamps that render colors accurately while maintaining high efficiency. This paper will discuss new introductions in light sources and lighting systems and how they may impact the design of luminous environments of the future.

Krailo, D. A.

1986-06-01T23:59:59.000Z

263

New high-flux two-stage optical designs for parabolic solar concentrators  

SciTech Connect

We present a new two-stage optical design for parabolic dish concentrators that can realistically attain close to 90% of the thermodynamic limit to concentration with practical, compact designs (e.g., at parabola rim half-angles of around 45[degrees]). For comparison, the parabolic dish-plus-compound parabolic concentrator secondary design, at this rim angle, achieves no more than 50% of the thermodynamic limit. Our new secondary concentrator is tailored to accept edge rays from the parabolic primary, and incurs less than one reflection on average. It necessitates displacing the absorber from the parabola's focal plane, along the concentrator's optic axis, toward the primary reflector, and constructing the secondary between the absorber and the primary. The secondary tailored edge-ray concentrators described here create new possibilities for building compact, extremely high flux solar furnaces and/or commercial parabolic dish systems.

Friedman, R.P.; Gordon, J.M. (Ben-Gurion Univ. of the Negev, Sede Boqer (Israel) Ben-Gurion Univ. of the Negev, Beersheva (Israel)); Ries, H. (Weizmann Institute of Science, Rehovot (Israel))

1993-11-01T23:59:59.000Z

264

Characteristics of quadratic electro-optic effects and electro-absorption process in CdSe parabolic quantum dots  

Science Conference Proceedings (OSTI)

The nonlinear susceptibilities have been calculated theoretically for CdSe disk-like parabolic quantum dots by using a two-energy-level model in the strong-confinement regime. The confined wave functions and eigenenergies of excitons in parabolic quantum ... Keywords: Electro-optical effects, Excitons, Parabolic quantum dot

Shufei Xie; Guiguang Xiong; Xiaobo Feng; Zhihong Chen

2007-06-01T23:59:59.000Z

265

Domain Decomposition via Explicit/Implicit Time Marching 1 Polynomial Collocation Using a Domain Decomposition Solution to Parabolic  

E-Print Network (OSTI)

Decomposition Solution to Parabolic PDE's via the Penalty Method and Explicit/Implicit Time Marching Kelly Black 1 Abstract A domain decomposition method is examined to solve a time dependent parabolic equation05. (1) Introduction We examine a domain decomposition method for solving a parabolic equation using

266

Spectral inequalities for non-selfadjoint elliptic operators and application to the null-controllability of parabolic systems  

E-Print Network (OSTI)

-controllability of parabolic systems Matthieu L´eautaud November, 2009 Abstract We consider elliptic operators A on a bounded the construction of a control for the non-selfadjoint parabolic problem tu + Au = Bg. In particular, the L2 norm are provided for systems of weakly coupled parabolic equations and for the measurement of the level sets

Paris-Sud XI, Université de

267

Parabolic focal conics and polygonal textures in lipid liquid crystals (*) S. A. Asher and P. S. Pershan  

E-Print Network (OSTI)

161 Parabolic focal conics and polygonal textures in lipid liquid crystals (*) S. A. Asher and P. S crystals. The parabolic focal conic model proposed by Rosenblatt, Pindak, Clark and Meyer for the polygonal as the strains inducing them are increased. The parabolic focal conic model does not completely describe

Asher, Sanford A.

268

The symmetric parabolic resonance This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-Print Network (OSTI)

The symmetric parabolic resonance This article has been downloaded from IOPscience. Please scroll Nonlinearity 23 (2010) 1325­1351 doi:10.1088/0951-7715/23/6/005 The symmetric parabolic resonance V Rom-Kedar1 Treschev Abstract The parabolic resonance instability emerges in diverse applications ranging from optical

269

IEEE TRANSACTIONS ON AUTOMATIC CONTROL, VOL. 53, NO. 7, AUGUST 2008 1575 Adaptive Boundary Control for Unstable Parabolic  

E-Print Network (OSTI)

for Unstable Parabolic PDEs--Part I: Lyapunov Design Miroslav Krstic, Fellow, IEEE, and Andrey Smyshlyaev, Member, IEEE Abstract--We develop adaptive controllers for parabolic par- tial differential equations for parabolic PDEs con- trolled from a boundary and containing unknown destabilizing parameters affecting

Krstic, Miroslav

270

IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 34, NO. 4, OCTOBER 2009 617 Extension of the Rotated Elastic Parabolic Equation  

E-Print Network (OSTI)

Elastic Parabolic Equation to Beach and Island Propagation Jon M. Collis, William L. Siegmann, Senior sloping interfaces and boundaries with the parabolic equation method have been an active area of research transformation techniques. The variable-rotated parabolic equation is among recent advances in this area

271

Test results, Industrial Solar Technology parabolic trough solar collector  

DOE Green Energy (OSTI)

Sandia National Laboratories and Industrial Solar Technology are cost-sharing development of advanced parabolic trough technology. As part of this effort, several configurations of an IST solar collector were tested to determine the collector efficiency and thermal losses with black chrome and black nickel receiver selective coatings, combined with aluminized film and silver film reflectors, using standard Pyrex{reg_sign} and anti-reflective coated Pyrex{reg_sign} glass receiver envelopes. The development effort has been successful, producing an advanced collector with 77% optical efficiency, using silver-film reflectors, a black nickel receiver coating, and a solgel anti-reflective glass receiver envelope. For each receiver configuration, performance equations were empirically derived relating collector efficiency and thermal losses to the operating temperature. Finally, equations were derived showing collector performance as a function of input insolation value, incident angle, and operating temperature.

Dudley, V.E. [EG and G MSI, Albuquerque, NM (United States); Evans, L.R.; Matthews, C.W. [Sandia National Labs., Albuquerque, NM (United States)

1995-11-01T23:59:59.000Z

272

Use of compound parabolic concentrator for solar energy collection  

DOE Green Energy (OSTI)

The joint team of Argonne National Laboratory (ANL) and the University of Chicago is reporting their midyear results of a proof-of-concept investigation of the Compound Parabolic Concentrator (CPC) for solar-energy collection. The CPC is a non-imaging, optical-design concept for maximally concentrating radiant energy onto a receiver. This maximum concentration corresponds to a relative aperture (f/number) of 0.5, which is well beyond the limit for imaging collectors. We have constructed an X3 concentrating flat-plate collector 16 ft/sup 2/ in area. This collector has been tested in a trailer laboratory facility built at ANL. The optical and thermal performance of this collector was in good agreement with theory. We have constructed an X10 collector (8 ft/sup 2/) and started testing. A detailed theoretical study of the optical and thermal characteristics of the CPC design has been performed.

Rabi, A.; Sevcik, V.J.; Giugler, R.M.; Winston, R.

1974-01-01T23:59:59.000Z

273

Fifth parabolic dish solar thermal power program annual review: proceedings  

DOE Green Energy (OSTI)

The primary objective of the Review was to present the results of activities within the Parabolic Dish Technology and Module/Systems Development element of the Department of Energy's Solar Thermal Energy Systems Program. The Review consisted of nine technical sessions covering overall Project and Program aspects, Stirling and Brayton module development, concentrator and engine/receiver development, and associated hardware and test results to date; distributed systems operating experience; international dish development activities; and non-DOE-sponsored domestic dish activities. A panel discussion concerning business views of solar electric generation was held. These Proceedings contain the texts of presentations made at the Review, as submitted by their authors at the beginning of the Review; therefore, they may vary slightly from the actual presentations in the technical sessions.

None

1984-03-01T23:59:59.000Z

274

Overview of software development at the Parabolic Dish Test Site  

DOE Green Energy (OSTI)

The development history of the data acquisition and data analysis software is discussed in this report. The software development occurred between 1978 and 1984 in support of solar energy module testing at the Jet Propulsion Laboratory's Parabolic Dish Test Site, located within Edwards Test Station. The development went through incremental stages, starting with a simple single-user BASIC set of programs, and progressing to the relative complex multi-user FORTRAN system that was used until the termination of the project. Additional software in support of testing is discussed including software in support of the meteorological subsystem and the Test Bed Concentrator Control Console interface. Conclusions and recommendations for further development are discussed.

Miyazono, C.K.

1985-07-15T23:59:59.000Z

275

Optimal Control of a Parabolic Equation with Dynamic Boundary Condition  

SciTech Connect

We investigate a control problem for the heat equation. The goal is to find an optimal heat transfer coefficient in the dynamic boundary condition such that a desired temperature distribution at the boundary is adhered. To this end we consider a function space setting in which the heat flux across the boundary is forced to be an L{sup p} function with respect to the surface measure, which in turn implies higher regularity for the time derivative of temperature. We show that the corresponding elliptic operator generates a strongly continuous semigroup of contractions and apply the concept of maximal parabolic regularity. This allows to show the existence of an optimal control and the derivation of necessary and sufficient optimality conditions.

Hoemberg, D., E-mail: hoemberg@wias-berlin.de; Krumbiegel, K., E-mail: krumbieg@wias-berlin.de [Weierstrass Institute for Applied Mathematics and Stochastics, Nonlinear Optimization and Inverse Problems (Germany); Rehberg, J., E-mail: rehberg@wias-berlin.de [Weierstrass Institute for Applied Mathematics and Stochastics, Partial Differential Equations (Germany)

2013-02-15T23:59:59.000Z

276

Thermal design of compound parabolic concentrating solar-energy collectors  

SciTech Connect

A theoretical analysis of the heat exchanges in a Compound Parabolic Concentrator solar energy collector is presented. The absorber configuration considered is that of a tube (with or without a spectrally-selective surface) either directly exposed or enclosed within one or two glass envelopes. The annular cavity formed between the tube and the surrounding envelope can be either air-filled or evacuated. The optimal annular gap, which leads to the best overall collector efficiency, has been predicted for the nonevacuated arrangement. It was found to be approximately 5 mm for the considered geometry. The evacuation of the annular cavity or the application of a selective surface, separately employed, are demonstrated to yield improvements of the same order.

Prapas, D.E.; Norton, B.; Probert, S.D.

1987-05-01T23:59:59.000Z

277

Task Routing for Prediction Tasks Haoqi Zhang  

E-Print Network (OSTI)

Harvard SEAS Microsoft Research Cambridge, MA 02138, USA Redmond, WA 98052, USA {hq, yiling, parkes, Economics, Theory Keywords Scoring rules, task routing, social networks 1. INTRODUCTION Organizations rely is crucial for the suc- cess of an organization. Accomplishing a task may require the expertise of multiple

Chen, Yiling

278

FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force Meeting Agenda FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force Meeting Agenda February 26, 2009 Task Force...

279

SHADE: a computer model for evaluating the optical performance of two-axis tracking parabolic concentrators  

DOE Green Energy (OSTI)

A computer model SHADE (Selection of Heliostat Arrangement for Distributed Engines) has been developed at the Pacific Northwest Laboratory to aid in determining the optical performance of two-axis tracking parabolic concentrators. The shading of individual mirror assemblies in a field of parabolic dishes determines the optimal field arrangement and the most efficient method of plant operation. SHADE provides a simple and inexpensive analytical tool for examining certain design aspects of solar thermal power systems using a network of point-focusing parabolic concentrators.

Apley, W. J.

1979-05-01T23:59:59.000Z

280

arXiv:math/0302209v1[math.AG]18Feb2003 THETA FUNCTIONS ON THE MODULI SPACE OF PARABOLIC  

E-Print Network (OSTI)

arXiv:math/0302209v1[math.AG]18Feb2003 THETA FUNCTIONS ON THE MODULI SPACE OF PARABOLIC BUNDLES parabolic vector bundles of rank r, trivial determinant and fixed parabolic structure at I better bound, in the sense that it does not depend on the genus g of the curve [Po]. The parabolic case

Sorger, Christoph

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


281

Current and Future Economics of Parabolic Trough Technology  

Science Conference Proceedings (OSTI)

Solar energy is the largest energy resource on the planet. Unfortunately, it is largely untapped at present, in part because sunlight is a very diffuse energy source. Concentrating solar power (CSP) systems use low cost reflectors to concentrate the sun's energy to allow it to be used more effectively. Concentrating solar power systems are also well suited for large solar power plants that can be connected into the existing utility infrastructure. These two facts mean that CSP systems can be used to make a meaningful difference in energy supply in a relatively short period. CSP plants are best suited for the arid climates in the Southwestern United States, Northern Mexico, and many desert regions around the globe. A recent Western Governors' Association siting study [1] found that the solar potential in the U.S. Southwest is at least 4 times the total U.S. electric demand even after eliminating urban areas, environmentally sensitive areas, and all regions with a ground slope greater than 1%.While it is currently not practical to power the whole county from the desert southwest, only a small portion of this area is needed to make a substantial contribution to future U.S. electric needs. Many of the best sites are near existing high-voltage transmission lines and close to major power load centers in the Southwest (Los Angeles, Las Vegas, and Phoenix). In addition, the power provided by CSP technologies has strong coincidence with peak electric demand, especially in the Southwest where peak demand corresponds in large part to air conditioning loads. Parabolic troughs currently represent the most cost-effective CSP technology for developing large utility-scale solar electric power systems. These systems are also one of the most mature solar technologies, with commercial utility-scale plants that have been operating for over 20 years. In addition, substantial improvements have been made to the technology in recent years including improved efficiency and the addition of thermal energy storage. The main issue for parabolic trough technology is that the cost of electricity is still higher than the cost of electricity from conventional natural gas-fired power plants. Although higher natural gas prices are helping to substantially reduce the difference between the cost of electricity from solar and natural gas plants, in the near-term increased incentives such as the 30% Investment Tax Credit (ITC) are needed to make CSP technology approach competitiveness with natural gas power on a financial basis. In the longer term, additional reductions in the cost of the technology will be necessary. This paper looks at the near-term potential for parabolic trough technology to compete with conventional fossil power resources in the firm, intermediate load power market and at the longer term potential to compete in the baseload power market. The paper will consider the potential impact of a reduced carbon emissions future.

Price, H.; Mehos, M.; Kutscher, C.; Blair, N.

2007-01-01T23:59:59.000Z

282

Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Parabolic-trough solar water heating is Parabolic-trough solar water heating is a well-proven technology that directly sub- stitutes renewable energy for conventional energy in water heating. Parabolic-trough collectors can also drive absorption cooling systems or other equipment that runs off a thermal load. There is considerable potential for using these technologies at Federal facil- ities in the Southwestern United States or other areas with high direct-beam solar radi- ation. Facilities such as jails, hospitals, and barracks that consistently use large volumes of hot water are particularly good candi- dates. Use of parabolic-trough systems helps Federal facilities comply with Executive Order 12902's directive to reduce energy use by 30% by 2005 and advance other efforts to get the Federal government to set a good

283

Heat-Loss Testing of Solel's UVAC3 Parabolic Trough Receiver  

DOE Green Energy (OSTI)

For heat-loss testing on two Solel UVAC3 parabolic trough receivers, a correlation developed predicts receiver heat loss as a function of the difference between avg absorber and ambient temperatures.

Burkholder, F.; Kutscher, C.

2008-01-01T23:59:59.000Z

284

Wind Tunnel Tests of Parabolic Trough Solar Collectors: March 2001--August 2003  

DOE Green Energy (OSTI)

Conducted extensive wind-tunnel tests on parabolic trough solar collectors to determine practical wind loads applicable to structural design for stress and deformation, and local component design for concentrator reflectors.

Hosoya, N.; Peterka, J. A.; Gee, R. C.; Kearney, D.

2008-05-01T23:59:59.000Z

285

The parabolic Sturmian-function basis representation of the six-dimensional Coulomb Green's function  

E-Print Network (OSTI)

The square integrable basis set representation of the resolvent of the asymptotic three-body Coulomb wave operator in parabolic coordinates is obtained. The resulting six-dimensional Green's function matrix is expressed as a convolution integral over separation constants.

S. A. Zaytsev

2008-06-03T23:59:59.000Z

286

Custom Engineering parabolic glass reflector for the Sandia prototype solar collector  

DOE Green Energy (OSTI)

The parabolic glass reflector, designed and constructed by Custom Engineering, Incorporated, is described. A brief summary of its performance as part of the Sandia prototype trough solar collector system is given.

Otts, J.; Sallis, D.

1981-08-01T23:59:59.000Z

287

Mechanical development of the actuation system of a parabolic solar trough  

E-Print Network (OSTI)

This thesis documents my personal contribution to the engineering and design of an actuation system with the purpose of rotating a parabolic solar trough to track the sun throughout the day. The primary focus of the design ...

O'Rourke, Conor R. (Conor Rakis)

2011-01-01T23:59:59.000Z

288

Participation in multilateral effort to develop high performance integrated CPC evacuated collectors. [Compound Parabolic Concentrator (CPC)  

SciTech Connect

The University of Chicago Solar Energy Group has had a continuing program and commitment to develop an advanced evacuated solar collector integrating nonimaging concentration into its design. During the period from 1985--1987, some of our efforts were directed toward designing and prototyping a manufacturable version of an Integrated Compound Parabolic Concentrator (ICPC) evacuated collector tube as part of an international cooperative effort involving six organizations in four different countries. This multilateral'' project made considerable progress towards a commercially practical collector. One of two basic designs considered employed a heat pipe and an internal metal reflector CPC. We fabricated and tested two large diameter (125mm) borosilicate glass collector tubes to explore this concept. The other design also used a large diameter (125mm) glass tube but with a specially configured internal shaped mirror CPC coupled to a U-tube absorber. Performance projections in a variety of systems applications using the computer design tools developed by the International Energy Agency (IEA) task on evacuated collectors were used to optimize the optical and thermal design. The long-term goal of this work continues to be the development of a high efficiency, low cost solar collector to supply solar thermal energy at temperatures up to 250{degree}C. Some experience and perspectives based on our work are presented and reviewed. Despite substantial progress, the stability of research support and the market for commercial solar thermal collectors were such that the project could not be continued. A cooperative path involving university, government and industrial collaboration remains the most attractive near term option for developing a commercial ICPC.

Winston, R.; O'Gallagher, J.J.

1992-05-31T23:59:59.000Z

289

Classification of Invariant Differential Operators for Non-Compact Lie Algebras via Parabolic Relations  

E-Print Network (OSTI)

In the present paper we review the progress of the project of classification and construction of invariant differential operators for non-compact semisimple Lie groups. Our starting points is the class of algebras, which we called earlier 'conformal Lie algebras' (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this we introduced recently the new notion of {\\it parabolic relation} between two non-compact semisimple Lie algebras $\\cal G$ and $\\cal G'$ that have the same complexification and possess maximal parabolic subalgebras with the same complexification. Thus, we consider the exceptional algebra $E_{7(7)}$ which is parabolically related to the CLA $E_{7(-25)}$. Other interesting examples are the orthogonal algebras $so(p,q)$ all of which are parabolically related to the conformal algebra $so(n,2)$ with $p+q=n+2$, the parabolic subalgebras including the Lorentz subalgebra $so(n-1,1)$ and its analogs $so(p-1,q-1)$. Further we consider the algebras $sl(2n,R)$ and for $n=2k$ the algebras $su^*(4k)$ which are parabolically related to the CLA $su(n,n)$. Further we consider the algebras $sp(r,r)$ which are parabolically related to the CLA $sp(2r,R)$. We consider also $E_{6(6)}$ and $E_{6(2)}$ which are parabolically related to the hermitian symmetric case $E_{6(-14)}$.

V. K. Dobrev

2013-11-29T23:59:59.000Z

290

Stability in terms of two measures for a class of semilinear impulsive parabolic equations  

SciTech Connect

The problem of stability in terms of two measures is considered for semilinear impulsive parabolic equations. A new version of the comparison method is proposed, and sufficient conditions for stability in terms of two measures are obtained on this basis. An example of a hybrid impulsive system formed by a system of ordinary differential equations coupled with a partial differential equation of parabolic type is given. The efficiency of the described approaches is demonstrated. Bibliography: 24 titles.

Dvirnyj, Aleksandr I; Slyn'ko, Vitalij I

2013-04-30T23:59:59.000Z

291

Optical analysis and optimization of parabolic-trough collectors: a user's guide  

DOE Green Energy (OSTI)

The results of a detailed optical analysis of parabolic trough solar collectors are summarized by a few universal graphs and curve fits. These graphs enable the designer of parabolic trough collectors to calculate the performance and to optimize the design with a simple hand calculator. The method is illustrated by specific examples that are typical of practical applications. The sensitivity of the optimization to changes in collector parameters and operating conditions is evaluated.

Bendt, P.; Rabl, A.; Gaul, H.W.

1981-07-01T23:59:59.000Z

292

Comparison of Fresnel lenses and parabolic mirrors as solar energy concentrators  

SciTech Connect

This paper compares the gain that can be achieved with a one- or two-stage concentrator, when the first stage is a Fresnel lens or a parabolic mirror, as a function of the luminosity of the concentrator. The results show that the achievable gain using a parabolic mirror is greater than that obtained using a flat or roof lens but is lower than that obtained using a curved lens.

Lorenzo, E.; Luque, A.

1982-05-15T23:59:59.000Z

293

Conservation Laws and Potential Symmetries of Linear Parabolic Equations  

E-Print Network (OSTI)

We carry out an extensive investigation of conservation laws and potential symmetries for the class of linear (1+1)-dimensional second-order parabolic equations. The group classification of this class is revised by employing admissible transformations, the notion of normalized classes of differential equations and the adjoint variational principle. All possible potential conservation laws are described completely. They are in fact exhausted by local conservation laws. For any equation from the above class the characteristic space of local conservation laws is isomorphic to the solution set of the adjoint equation. Effective criteria for the existence of potential symmetries are proposed. Their proofs involve a rather intricate interplay between different representations of potential systems, the notion of a potential equation associated with a tuple of characteristics, prolongation of the equivalence group to the whole potential frame and application of multiple dual Darboux transformations. Based on the tools developed, a preliminary analysis of generalized potential symmetries is carried out and then applied to substantiate our construction of potential systems. The simplest potential symmetries of the linear heat equation, which are associated with single conservation laws, are classified with respect to its point symmetry group. Equations possessing infinite series of potential symmetry algebras are studied in detail.

Roman O. Popovych; Michael Kunzinger; Nataliya M. Ivanova

2007-06-04T23:59:59.000Z

294

Slope Error Measurement Tool for Solar Parabolic Trough Collectors: Preprint  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory (NREL) has developed an optical measurement tool for parabolic solar collectors that measures the combined errors due to absorber misalignment and reflector slope error. The combined absorber alignment and reflector slope errors are measured using a digital camera to photograph the reflected image of the absorber in the collector. Previous work using the image of the reflection of the absorber finds the reflector slope errors from the reflection of the absorber and an independent measurement of the absorber location. The accuracy of the reflector slope error measurement is thus dependent on the accuracy of the absorber location measurement. By measuring the combined reflector-absorber errors, the uncertainty in the absorber location measurement is eliminated. The related performance merit, the intercept factor, depends on the combined effects of the absorber alignment and reflector slope errors. Measuring the combined effect provides a simpler measurement and a more accurate input to the intercept factor estimate. The minimal equipment and setup required for this measurement technique make it ideal for field measurements.

Stynes, J. K.; Ihas, B.

2012-04-01T23:59:59.000Z

295

Mechanism of Hydrogen Formation in Solar Parabolic Trough Receivers  

SciTech Connect

Solar parabolic trough systems for electricity production are receiving renewed attention, and new solar plants are under construction to help meet the growing demands of the power market in the Western United States. The growing solar trough industry will rely on operating experience it has gained over the last two decades. Recently, researchers found that trough plants that use organic heat transfer fluids (HTF) such as Therminol VP-1 are experiencing significant heat losses in the receiver tubes. The cause has been traced back to the accumulation of excess hydrogen gas in the vacuum annulus that surrounds the steel receiver tube, thus compromising the thermal insulation of the receiver. The hydrogen gas is formed during the thermal decomposition of the organic HTF that circulates inside the receiver loop, and the installation of hydrogen getters inside the annulus has proven to be insufficient for controlling the hydrogen build-up over the lifetime of the receivers. This paper will provide an overview of the chemical literature dealing with the thermal decomposition of diphenyl oxide and biphenyl, the two constituents of Therminol VP-1.

Moens, L.; Blake, D. M.

2008-03-01T23:59:59.000Z

296

Experimental natural convective studies within a compound parabolic concentrator enclosure  

SciTech Connect

The contribution due to natural convection within a compound parabolic concentrator enclosure has been experimentally determined. These studies have been conducted within a 4X-CPC collector, having a receiver width of 3.175 cm (1.25 inches) and 2.44 m (96 inches) in length. The receiver was heated electrically while the aperture was provided with a duct that was cooled by water. The limbs of the collector were fabricated from aluminum. Temperatures were directly obtained with copper-constantan thermocouples located throughout the entire enclosure and provided the basis needed to calculate the different modes of heat transfer. The constant heat flux at the receiver translated to a nearly isothermal state. The rates of natural convection have been expressed in terms of a Nu-Ra correlation where 1.0x10/sup 7/ < Ra < 4.0x10/sup 7/. To suppress natural convection, a horizontal partition was introduced at different heights between the receiver and aperture. These results have been expressed as heat fluxes and temperature differences between the receiver and the aperture. This information made possible a comparison between the aperture-partition enclosure and a flat plate geometry.

Tatara, R.A.; Thodos, G.

1983-01-01T23:59:59.000Z

297

Solar Energy Task Force Report Technical Guidelines  

NLE Websites -- All DOE Office Websites (Extended Search)

swimming pool type, a single-glazed nonselective flat plate, a double-glazed selective flat plate, an evacuated tube module, and a concentrating parabolic tracker. Air systems...

298

The Advantage of Highly Controlled Lighting for Offices and Commercial Buildings  

E-Print Network (OSTI)

of Highly Controlled Lighting for Offices and Commercialefficient, customized lighting for open-office cubicles.s “ambient” and “tasklighting components, 2) occupancy

Rubinstein, Francis

2010-01-01T23:59:59.000Z

299

Task Routing for Prediction Tasks Haoqi Zhang  

E-Print Network (OSTI)

Harvard SEAS Microsoft Research Cambridge, MA 02138, USA Redmond, WA 98052, USA {hq, yiling, parkes. INTRODUCTION Organizations rely on a mix of expertise and on means for identifying and harnessing expertise effectively is crucial for the success of an organization. Accomplishing a task may require the expertise

Chen, Yiling

300

Design of a Transpired Air Heating Solar Collector with an Inverted Perforated Absorber and Asymmetric Compound Parabolic Concentrator.  

E-Print Network (OSTI)

?? absorber and an asymmetric compound parabolic concentrator was applied to increase the intensity of solar radiation incident on the perforated absorber. A 2D ray… (more)

Shams, Nasif

2013-01-01T23:59:59.000Z

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


301

ILC Citizens' Task Force  

NLE Websites -- All DOE Office Websites (Extended Search)

the Fermilab ILC Citizens' Task Force June 2008 Report of the Fermilab ILC Citizens' Task Force 3 Contents 1 Executive Summary 3 Chapter 1 Purpose 7 Chapter 2 Origins and Purpose of the Fermilab Citizens' Task Force 15 Chapter 3 Setting the Stage 19 Chapter 4 Current Status of High Energy Physics Research 25 Chapter 5 Bringing the Next-Generation Accelerator to Fermilab 31 Chapter 6 Learning from Past Projects 37 Chapter 7 Location, Construction and Operation of Facilities Beyond Fermilab's Borders 45 Chapter 8 Health and Safety 49 Chapter 9 Environment 53 Chapter 10 Economics 59 Chapter 11 Political Considerations 65 Chapter 12 Community Engagement 77 Chapter 13 Summary 81 Appendices Appendix A. Task Force Members Appendix B. Task Force Meetings and Topics

302

Four firms marketing new lighting products  

SciTech Connect

New lighting products on the market include a screw-in high-pressure sodium (HPS) retrofit from Teron Lighting Corp., a screw-in industrial HPS lamp from Guth Lighting, low-voltage task and display lighting fixtures from Capri Lighting, and a current-reducing device from Remtec. The article describes the energy savings, costs, and specifications of each product. (DCK)

1983-07-04T23:59:59.000Z

303

Composite Lighting Simulations with Lighting Networks  

E-Print Network (OSTI)

A whole variety of different techniques for simulating global illumination in virtual environments have been developed over recent years. Each technique, including Radiosity, Monte-Carlo ray- or photon tracing, and directional-dependent Radiance computations, is best suited for simulating only some special case environments. None of these techniques is currently able to efficiently simulate all important lighting effects in non-trivial scenes. In this paper, we describe a new approach for efficiently combining different global illumination algorithms to yield a composite lighting simulation: Lighting Networks. Lighting Networks can exploit the advantages of each algorithm and can combine them in such a way as to simulate lighting effects that could only be computed at great costs by any single algorithm. Furthermore, this approach allows a user to configure the Lighting Network to compute only specific lighting effects that are important for a given task, while avoiding a costly simulation of the full global illumination in a scene. We show how the light paths computed by a Lighting Network can be described using regular expressions. This mapping allows us to analyze the composite lighting simulation and ensure completeness and redundant-free computations. Several examples demonstrate the advantages and unique lighting effects that can be obtained using this technique. 1

Philipp Slusallek; Marc Stamminger; Wolfgang Heidrich; Jan-Christian Popp; Hans-peter Seidel

1998-01-01T23:59:59.000Z

304

Piecewise parabolic negative magnetoresistance of two-dimensional electron gas with triangular antidot lattice  

SciTech Connect

Extraordinary piecewise parabolic behavior of the magnetoresistance has been experimentally detected in the two-dimensional electron gas with a dense triangular lattice of antidots, where commensurability magnetoresistance oscillations are suppressed. The magnetic field range of 0-0.6 T can be divided into three wide regions, in each of which the magnetoresistance is described by parabolic dependences with high accuracy (comparable to the experimental accuracy) and the transition regions between adjacent regions are much narrower than the regions themselves. In the region corresponding to the weakest magnetic fields, the parabolic behavior becomes almost linear. The observed behavior is reproducible as the electron gas density changes, which results in a change in the resistance by more than an order of magnitude. Possible physical mechanisms responsible for the observed behavior, including so-called 'memory effects,' are discussed.

Budantsev, M. V., E-mail: budants@isp.nsc.ru; Lavrov, R. A.; Pogosov, A. G.; Zhdanov, E. Yu.; Pokhabov, D. A. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

2011-02-15T23:59:59.000Z

305

Wind load design methods for ground-based heliostats and parabolic dish collectors  

DOE Green Energy (OSTI)

The purpose of this design method is to define wind loads on flat heliostat and parabolic dish collectors in a simplified form. Wind loads are defined for both mean and peak loads accounting for the protective influence of upwind collectors, wind protective fences, or other wind-blockage elements. The method used to define wind loads was to generalize wind load data obtained during tests on model collectors, heliostats or parabolic dishes, placed in a modeled atmospheric wind in a boundary-layer wind-tunnel at Colorado State University. For both heliostats and parabolic dishes, loads are reported for solitary collectors and for collectors as elements of a field. All collectors were solid with negligible porosity; thus the effects of porosity in the collectors is not addressed.

Peterka, J.A.; Derickson, R.G. (Colorado State Univ., Fort Collins, CO (United States). Fluid Dynamics and Diffusion Lab.)

1992-09-01T23:59:59.000Z

306

Analysis of the influence of geography and weather on parabolic trough solar collector design  

DOE Green Energy (OSTI)

The potential performance of single-axis tracking parabolic trough solar collectors as a function of optical energy distribution and receiver size has been calculated for eleven sites using typical meteorological year input data. A simulation based on the SOLTES code was developed which includes the three-dimensional features of a parabolic trough and calculates the thermooptical tradeoffs. The capability of the thermooptical model has been confirmed by the comparison of calculated results with the experimental results from an all-day test of a parabolic trough. The results from this eleven-site analysis indicate a potential performance superiority of a north-south horizontal axis trough and, in addition, a high quality (optical error, sigma/sub system/ less than or equal to 0.007 radian) collector should be of the same geometric design for all of the sites investigated and probably for all regions of the country.

Treadwell, G.W.; Grandjean, N.R.; Biggs, F.

1980-03-01T23:59:59.000Z

307

NREL: TroughNet - Parabolic Trough Technology Models and Software Tools  

NLE Websites -- All DOE Office Websites (Extended Search)

Technology Models and Software Tools Technology Models and Software Tools Here you'll find information about models and software tools used to analyze parabolic trough power plant technology. They include: Annual Simulation Solar Advisor Model TRNSYS Other Analysis SolTRACE Receiver Model DView JEDI Annual Simulation Software Because solar power plants rely on an intermittent fuel supply-the sun-it is necessary to model the plant's performance on an hourly (or finer resolution) basis to understand and predict its annual performance. A number of performance and economics models are available for evaluating parabolic trough solar technologies. Industry also has developed a number of proprietary models for evaluating parabolic trough plants. Solar Advisor Model NREL, partnering with the U.S. Department of Energy's Solar Energy

308

Validation of the FLAGSOL parabolic trough solar power plant performance model  

DOE Green Energy (OSTI)

This paper describes the results of a validation of the FLAGSOL parabolic trough solar power plant performance model. The validation was accomplished by simulating an operating solar electric generating system (SEGS) parabolic trough solar thermal power plant and comparing the model output results with actual plant operating data. This comparison includes instantaneous, daily, and annual total solar thermal electric output, gross solar electric generation, and solar mode parasitic electric consumption. The results indicate that the FLAGSOL model adequately predicts the gross solar electric output of an operating plant, both on a daily and an annual basis.

Price, H.W. [National Renewable Energy Lab., Golden, CO (United States); Svoboda, P. [Flachglas-Solartechnik GmbH, Koeln (Germany); Kearney, D. [Kearney and Associates, Del Mar, CA (United States)

1994-10-01T23:59:59.000Z

309

Erlangen Program at Large--2: Inventing a wheel. The parabolic one  

E-Print Network (OSTI)

We discuss parabolic versions of Euler's identity e^{it}=cos t + i sin t. A purely algebraic approach based on dual numbers is known to produce a very trivial relation e^{pt} = 1+pt. Therefore we use a geometric setup of parabolic rotations to recover the corresponding non-trivial algebraic framework. Our main tool is Moebius transformations which turn out to be closely related to induced representations of the group SL(2,R). Keywords: complex numbers, dual numbers, double numbers, linear algebra, invariant, computer algebra, GiNaC

Vladimir V. Kisil

2007-07-27T23:59:59.000Z

310

Determination of freeze-protection heat loss from a parabolic trough solar system  

DOE Green Energy (OSTI)

A small-scale experiment was undertaken to determine practical control temperatures for a parabolic trough, pulsed-flow water freeze-protection scheme. Measurements were also taken of heat loss from stagnant water in the absorber tube under freezing ambient conditions. Using the experimental data and data available from the literature, manipulation of long-term weather data provided estimates of annual thermal losses to prevent freezing. In a cold climate such as Denver, Colorado's, which typically has 155 freezing days per year, such losses should be less than 0.7% of the annual energy delivered by an efficient parabolic trough system.

May, E.K.

1983-08-01T23:59:59.000Z

311

Parabolic Sturmians approach to the three-body continuum Coulomb problem  

E-Print Network (OSTI)

The three-body continuum Coulomb problem is treated in terms of the generalized parabolic coordinates. Approximate solutions are expressed in the form of a Lippmann-Schwinger type equation, where the Green's function includes the leading term of the kinetic energy and the total potential energy, whereas the potential contains the non-orthogonal part of the kinetic energy operator. As a test of this approach, the integral equation for the $(e^-,\\, e^-,\\, {{He}^{++}})$ system is solved numerically by using the parabolic Sturmian basis representation of the (approximate) potential. Convergence of the expansion coefficients of the solution is obtained as the basis set used to describe the potential is enlarged.

S. A. Zaytsev; Yu. V. Popov; B. Piraux

2011-08-19T23:59:59.000Z

312

On the iterated Crank-Nicolson for hyperbolic and parabolic equations in numerical relativity  

E-Print Network (OSTI)

The iterated Crank-Nicolson is a predictor-corrector algorithm commonly used in numerical relativity for the solution of both hyperbolic and parabolic partial differential equations. We here extend the recent work on the stability of this scheme for hyperbolic equations by investigating the properties when the average between the predicted and corrected values is made with unequal weights and when the scheme is applied to a parabolic equation. We also propose a variant of the scheme in which the coefficients in the averages are swapped between two corrections leading to systematically larger amplification factors and to a smaller numerical dispersion.

Gregor Leiler; Luciano Rezzolla

2006-01-31T23:59:59.000Z

313

Determination of a control parameter in a one-dimensional parabolic equation using the moving least-square approximation  

Science Conference Proceedings (OSTI)

In this paper the approximation of moving least-square (MLS) is used for finding the solution of a one-dimensional parabolic inverse problem with source control parameter. Comparing with other numerical methods based on meshes such as finite difference ... Keywords: inverse problem, meshless method, moving least-square approximation, overspecification, parabolic equation

Rongjun Cheng

2008-09-01T23:59:59.000Z

314

Fully discrete FEM-BEM method for a class of exterior nonlinear parabolic-elliptic problems in 2D  

Science Conference Proceedings (OSTI)

We considered a nonlinear parabolic equation in a bounded domain of R2 coupled with the Laplace equation in the corresponding exterior region. This kind of problems appears in the modelling of quasi-stationary electromagnetic fields. We chose ... Keywords: boundary elements, finite elements, parabolic-elliptic problem

María González

2006-10-01T23:59:59.000Z

315

Evolution in lighting  

SciTech Connect

Lights consume 20-25% of the nation's electricity, establishing strong incentives to develop more efficient lighting strategies. Attention is turning to where, when, and how we light our environment, and the potential savings add up to half the lighting load nationwide. Some types of lamp are more efficient than others, but characteristics other than energy consumption may dictate where they can be used. Current lighting strategies consider task requirements, light quality, and the potential for daylighting. Energy management systems that control the timing and intensity of light and new types of energy-efficient bulbs and fixtures are increasingly attractive to consumers. The effort will require continued research and the awareness of decision makers. 4 references, 8 figures.

Lihach, N.; Pertusiello, S.

1984-06-01T23:59:59.000Z

316

Lighting fundamentals handbook: Lighting fundamentals and principles for utility personnel  

SciTech Connect

Lighting accounts for approximately 30% of overall electricity use and demand in commercial buildings. This handbook for utility personnel provides a source of basic information on lighting principles, lighting equipment, and other considerations related to lighting design. The handbook is divided into three parts. Part One, Physics of Light, has chapters on light, vision, optics, and photometry. Part Two, Lighting Equipment and Technology, focuses on lamps, luminaires, and lighting controls. Part Three, Lighting Design Decisions, deals with the manner in which lighting design decisions are made and reviews relevant methods and issues. These include the quantity and quality of light needed for visual tasks, calculation methods for verifying that lighting needs are satisfied, lighting economics and methods for evaluating investments in efficient lighting systems, and miscellaneous design issues including energy codes, power quality, photobiology, and disposal of lighting equipment. The handbook contains a discussion of the role of the utility in promoting the use of energy-efficient lighting. The handbook also includes a lighting glossary and a list of references for additional information. This convenient and comprehensive handbook is designed to enable utility lighting personnel to assist their customers in developing high-quality, energy-efficient lighting systems. The handbook is not intended to be an up-to-date reference on lighting products and equipment.

Eley, C.; Tolen, T. (Eley (Charles) Associates, San Francisco, CA (United States)); Benya, J.R. (Luminae Souter Lighting Design, San Francisco, CA (United States))

1992-12-01T23:59:59.000Z

317

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B. Oliveira  

E-Print Network (OSTI)

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B gas in n-type wide parabolic quantum wells. A series of samples with different well widths at the Fermi level at low temperature only in the thinnest parabolic quantum wells. The suppression of the many

Gusev, Guennady

318

IASTED Conf. on Modeling, Identification and Control, February 14-17, 2000, Innsbuck, Austria 296 NYQUIST STABILITY TEST FOR A PARABOLIC PARTIAL  

E-Print Network (OSTI)

NYQUIST STABILITY TEST FOR A PARABOLIC PARTIAL DIFFERENTIAL EQUATION MIKLOS VAJTA Dept. of Mathematical.vajta@math.utwente.nl ABSTRACT The paper describes a Nyquist stability test applied to a parabolic partial differential equation differential equations. 1. PROBLEM STATEMENT A large class of parabolic partial differential equations (PDE

Al Hanbali, Ahmad

319

hal-00177601,version2-30Oct2007 A closed parabolic trough solar collector  

E-Print Network (OSTI)

issues that must be dealt with. The most important one is the receiver tube that absorbs the solar energy partially evacuated tube that is filled by a low-conductivity gas. While reducing the cost, this design also of parabolic trough for solar power plants is the one developed by the now defunct Luz during 1980s. The common

Paris-Sud XI, Université de

320

Homogenization of a degenerate parabolic problem in a highly heterogeneous medium with highly anisotropic fibers  

Science Conference Proceedings (OSTI)

We consider the homogenization of a heat transfer problem in a periodic medium, consisting of a set of highly anisotropic fibers surrounded by insulating layers, the whole being embedded in a third material having a conductivity of order 1. The conductivity ... Keywords: Degenerate parabolic problem, Highly anisotropic fibers, Highly heterogeneous medium, Homogenization

Ahmed Boughammoura

2009-01-01T23:59:59.000Z

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


321

The asymptotics of a solution of a parabolic equation as time increases without bound  

SciTech Connect

A boundary-value problem for a second order parabolic equation on a half-line is considered. A uniform asymptotic approximation to a solution to within any power of t{sup -1} is constructed and substantiated. Bibliography: 8 titles.

Degtyarev, Denis O; Il'in, Arlen M

2012-11-30T23:59:59.000Z

322

Solution blow-up for a class of parabolic equations with double nonlinearity  

SciTech Connect

We consider a class of parabolic-type equations with double nonlinearity and derive sufficient conditions for finite time blow-up of its solutions in a bounded domain under the homogeneous Dirichlet condition. To prove the solution blow-up we use a modification of Levine's method. Bibliography: 13 titles.

Korpusov, Maxim O [Lomonosov Moscow State University, Faculty of Physics, Moscow (Russian Federation)] [Lomonosov Moscow State University, Faculty of Physics, Moscow (Russian Federation)

2013-03-31T23:59:59.000Z

323

Brief paper: An LMI approach to H? boundary control of semilinear parabolic and hyperbolic systems  

Science Conference Proceedings (OSTI)

Exponential stability analysis and L"2-gain analysis are developed for scalar uncertain distributed parameter systems, governed by semilinear partial differential equations of parabolic and hyperbolic types. Sufficient exponential stability conditions ... Keywords: Distributed parameter systems, H? control, LMI, Lyapunov functional, Stability

Emilia Fridman; Yury Orlov

2009-09-01T23:59:59.000Z

324

Nuclear spin dynamics in parabolic quantum wells Ionel Tifrea* and Michael E. Flatte  

E-Print Network (OSTI)

Nuclear spin dynamics in parabolic quantum wells Ionel T¸ifrea* and Michael E. Flatte´ Department March 2004 We present a detailed analytical and numerical analysis of the nuclear spin dynamics of the electronic wave function in small electric fields. The nuclear spin relaxation via the hyperfine interaction

Flatte, Michael E.

325

The cylindrical parabolic mirror as reflector for solar collectors. Efficiencies and optimization  

DOE Green Energy (OSTI)

After introducing the concentration ratio and intercept factor of focusing collectors with parabolic cylinder mirrors, the energy balance equations were derived to determine the efficiencies under steady state conditions. The components of the collector were varied and optimized with respect to maximum efficiency. The dynamic behavior of the collector was calculated and the average efficiencies compared with the efficiencies in the steady state condition.

Koehne, R.

1976-10-27T23:59:59.000Z

326

Light-Matter Quantum Interface  

E-Print Network (OSTI)

We propose a quantum interface which applies multiple passes of a pulse of light through an atomic sample with phase/polarization rotations in between the passes. Our proposal does not require nonclassical light input or measurements on the system, and it predicts rapidly growing unconditional entanglement of light and atoms from just coherent inputs. The proposed interface makes it possible to achieve a number of tasks within quantum information processing including teleportation between light and atoms, quantum memory for light and squeezing of atomic and light variables.

K. Hammerer; K. Molmer; E. S. Polzik; J. I. Cirac

2003-12-18T23:59:59.000Z

327

Light-Light Scattering  

E-Print Network (OSTI)

For a long time, it is believed that the light by light scattering is described properly by the Lagrangian density obtained by Heisenberg and Euler. Here, we present a new calculation which is based on the modern field theory technique. It is found that the light-light scattering is completely different from the old expression. The reason is basically due to the unphysical condition (gauge condition) which was employed by the QED calcualtion of Karplus and Neumann. The correct cross section of light-light scattering at low energy of $(\\frac{\\omega}{m} \\ll 1)$ can be written as $ \\displaystyle{\\frac{d\\sigma}{d\\Omega}=\\frac{1}{(6\\pi)^2}\\frac{\\alpha^4} {(2\\omega)^2}(3+2\\cos^2\\theta +\\cos^4\\theta)}$.

Kanda, Naohiro

2011-01-01T23:59:59.000Z

328

Light-Light Scattering  

E-Print Network (OSTI)

For a long time, it is believed that the light by light scattering is described properly by the Lagrangian density obtained by Heisenberg and Euler. Here, we present a new calculation which is based on the modern field theory technique. It is found that the light-light scattering is completely different from the old expression. The reason is basically due to the unphysical condition (gauge condition) which was employed by the QED calcualtion of Karplus and Neumann. The correct cross section of light-light scattering at low energy of $(\\frac{\\omega}{m} \\ll 1)$ can be written as $ \\displaystyle{\\frac{d\\sigma}{d\\Omega}=\\frac{1}{(6\\pi)^2}\\frac{\\alpha^4} {(2\\omega)^2}(3+2\\cos^2\\theta +\\cos^4\\theta)}$.

Naohiro Kanda

2011-06-03T23:59:59.000Z

329

Automated task allocation  

Science Conference Proceedings (OSTI)

The goal of the paradigm shift in Air Traffic Management (ATM) is to increase its overall performance by means of redesigning processes, evolving to a more automated, autonomous and predictable system. Nevertheless, when dealing with automation, it is ... Keywords: ATM, anticipatory, autonomous, centric, compensatory, decision support tools, level of automation, operations research, optimisation, performance metrics, task allocation

Rocío Barragán Montes, Eduardo García, Francisco Javier Sáez Nieto

2013-05-01T23:59:59.000Z

330

Format for Generic Task Description  

Science Conference Proceedings (OSTI)

Task: Submitting Proposals. Containing Scenario: Fast Tracking a Battery Standard Description: Review of the proposed ...

331

Drivers of Residual Estuarine Circulation in Tidally Energetic Estuaries: Straight and Irrotational Channels with Parabolic Cross Section  

Science Conference Proceedings (OSTI)

The generation of residual circulation in a tidally energetic estuary with constant longitudinal salinity gradient and parabolic cross section is examined by means of a two-dimensional cross-sectional numerical model, neglecting river runoff and ...

Hans Burchard; Robert D. Hetland; Elisabeth Schulz; Henk M. Schuttelaars

2011-03-01T23:59:59.000Z

332

Fluorescent Lighting | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Fluorescent Lighting Fluorescent Lighting Fluorescent Lighting October 17, 2013 - 5:44pm Addthis Fluorescent Lighting Fluorescent Lighting Fluorescent lamps use 25%-35% of the energy used by incandescent products to provide a similar amount of light. They also last about 10 times longer (7,000-24,000 hours). The two general types of fluorescent lamps are: Compact fluorescent lamps (CFLs) -- commonly found with integral ballasts and screw bases, these are popular lamps often used in household fixtures Fluorescent tube and circline lamps -- typically used for task lighting such as garages and under cabinet fixtures, and for lighting large areas in commercial buildings. CFLs CFLs combine the energy efficiency of fluorescent lighting with the convenience and popularity of incandescent fixtures. CFLs fit most fixtures

333

NREL: TroughNet - Parabolic Trough Technology Solar Resource Data and Tools  

NLE Websites -- All DOE Office Websites (Extended Search)

Solar Resource Data and Tools Solar Resource Data and Tools Here you'll find resources on solar radiation data and tools for siting parabolic trough power plants. This includes solar radiation data for power plants in the United States and worldwide. You'll also find resources for direct solar radiation instrumentation. For an overview on solar resource terms and direct beam radiation used for concentrating solar power technologies, see NREL's Shining On Web site. U.S. Solar Radiation Resource Data The following resources include maps, and hourly metrological and solar resource data for parabolic trough power plants sites in the United States. NREL Concentrating Solar Power Resource Maps Features direct normal solar radiation maps of the southwestern United States, including state maps for Arizona, California, Colorado, New Mexico,

334

Near-term improvements in parabolic troughs: an economic and performance assessment  

DOE Green Energy (OSTI)

Improved parabolic-trough concentrating collectors will result from better design, improved fabrication techniques, and the development and utilization of improved materials. This analysis qualifies the performance potential of various parabolic-trough component improvements from a systems viewpoint and uses these performance data to determine the worth of each improvement on an economic basis. The improvements considered are evacuated receivers, silvered-glass reflectors, improved receiver, selective coatings, higher optical accuracy concentrations, and higher transmittance receiver glazings. Upper-bound costs for each improvement are provided as well as estimates of the increased solar system rates of return that are made possible by these improvements. The performance and economic potential of some of these improvements are shown to be substantial, especially at higher collector operating temperatures.

Gee, R.; Murphy, L.M.

1981-08-01T23:59:59.000Z

335

Gas Turbine/Solar Parabolic Trough Hybrid Design Using Molten Salt Heat Transfer Fluid: Preprint  

DOE Green Energy (OSTI)

Parabolic trough power plants can provide reliable power by incorporating either thermal energy storage (TES) or backup heat from fossil fuels. This paper describes a gas turbine / parabolic trough hybrid design that combines a solar contribution greater than 50% with gas heat rates that rival those of natural gas combined-cycle plants. Previous work illustrated benefits of integrating gas turbines with conventional oil heat-transfer-fluid (HTF) troughs running at 390?C. This work extends that analysis to examine the integration of gas turbines with salt-HTF troughs running at 450 degrees C and including TES. Using gas turbine waste heat to supplement the TES system provides greater operating flexibility while enhancing the efficiency of gas utilization. The analysis indicates that the hybrid plant design produces solar-derived electricity and gas-derived electricity at lower cost than either system operating alone.

Turchi, C. S.; Ma, Z.

2011-08-01T23:59:59.000Z

336

Parabolic sturmians approach to the three-body continuum Coulomb problem  

SciTech Connect

The three-body continuum Coulomb problem is treated in terms of the generalized parabolic coordinates. Approximate solutions are expressed in the form of a Lippmann-Schwinger-type equation, where the Green's function includes the leading term of the kinetic energy and the total potential energy, whereas the potential contains the non-orthogonal part of the kinetic energy operator. As a test of this approach, the integral equation for the (e{sup -}, e{sup -}, He{sup ++}) system has been solved numerically by using the parabolic Sturmian basis representation of the (approximate) potential. Convergence of the expansion coefficients of the solution has been obtained as the basis set used to describe the potential is enlarged.

Zaytsev, S. A., E-mail: zaytsev@fizika.khstu.ru [Pacific National University (Russian Federation); Popov, Yu. V. [Moscow State University, Nuclear Physics Institute (Russian Federation)] [Moscow State University, Nuclear Physics Institute (Russian Federation); Piraux, B. [Universite catholique de Louvain, Institute of Condensed Matter and Nanosciences (Belgium)] [Universite catholique de Louvain, Institute of Condensed Matter and Nanosciences (Belgium)

2013-03-15T23:59:59.000Z

337

Reducing the Cost of Energy from Parabolic Trough Solar Power Plants: Preprint  

DOE Green Energy (OSTI)

Parabolic trough solar technology is the most proven and lowest cost large-scale solar power technology available today, primarily because of the nine large commercial-scale solar power plants that are operating in the California Mojave Desert. However, no new plants have been built during the past ten years because the cost of power from these plants is more expensive than power from conventional fossil fuel power plants. This paper reviews the current cost of energy and the potential for reducing the cost of energy from parabolic trough solar power plant technology based on the latest technological advancements and projected improvements from industry and sponsored R&D. The paper also looks at the impact of project financing and incentives on the cost of energy.

Price, H.; Kearney, D.

2003-01-01T23:59:59.000Z

338

Parabolic Coordinates and the Hydrogen Atom in Spaces H_{3} and S_{3}  

E-Print Network (OSTI)

The Coulomb problem for Schr\\"{o}dinger equation is examined, in spaces of constant curvature, Lobachevsky H_{3} and Riemann S_{3} models, on the base of generalized parabolic coordinates. In contrast to the hyperbolic case, in spherical space S_{3} such parabolic coordinates turn to be complex-valued, with additional constraint on them. The technique of the use of such real and complex coordinates in two space models within the method of separation of variables in Schr\\"{o}dinger equation with Kepler potential is developed in detail; the energy spectra and corresponding wave functions for bound states have been constructed in explicit form for both spaces; connections with Runge-Lenz operators in both curved space models are described.

V. M. Red'kov; E. M. Ovsiyuk

2011-08-31T23:59:59.000Z

339

Analysis of static and quasi-static cross compound parabolic concentrators  

SciTech Connect

Static and quasi-static concentrators present interesting characteristics for obtaining photovoltaic solar energy. In this work we study the characteristics of the crossed compound parabolic concentrator, formed by the intersection of two cyclindrical compound parabolic concentrators (CPC). Bifacial cells are used in this concentrator as a requirement for obtaining higher concentrations. Static and quasi-static concentrators see the sun as an extended source, so a simplified source model of radiance for the sky of Madrid is used. The figures of merit of a lossless concentrator are studied and the most important parameters influencing its optical behavior are discussed. We conclude that these concentrators obtain results that lead to a decrease in the cost of photovoltaic energy.

Molledo, A.G.; Luque, A.

1984-06-15T23:59:59.000Z

340

Homogenization of a singularly perturbed degenerated parabolic equation and application to seabed dune and megaripple morphodynamics in tided environment  

E-Print Network (OSTI)

In this paper we build models for short-term, mean-term and long-term dynamics of dune and megariple morphodynamics. They are models that are degenerated parabolic equations which are, moreover, singularly perturbed. We, then give an existence and uniqueness result for the short-term and mean-term models. This result is based on a time-space periodic solution existence result for degenerated parabolic equation that we set out. Finally the short-term model is homogenized.

Faye, Ibrahima; Seck, Diaraf

2009-01-01T23:59:59.000Z

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


341

Peculiarities of parabolic-barrier penetrability and thermal decay rate with the quantum diffusion approach  

SciTech Connect

With the quantum diffusion approach, the passing probability through the parabolic barrier is examined in the limit of linear coupling in the momentum between the collective subsystem and environment. The dependencies of the penetrability on time, energy, and the coupling strength between the interacting subsystems are studied. The quasistationary thermal decay rate from a metastable state is considered in the cases of linear couplings both in the momentum and in the coordinate.

Kuzyakin, R. A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Omsk State Transport University, 644046 Omsk (Russian Federation); Sargsyan, V. V.; Adamian, G. G.; Antonenko, N. V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

2011-06-15T23:59:59.000Z

342

Stabilization of solutions of quasilinear second order parabolic equations in domains with non-compact boundaries  

SciTech Connect

The first mixed problem with homogeneous Dirichlet boundary condition and initial function with compact support is considered for quasilinear second order parabolic equations in a cylindrical domain D=(0,{infinity})x{Omega}. Upper bounds are obtained, which give the rate of decay of the solutions as t{yields}{infinity} as a function of the geometry of the unbounded domain {Omega} subset of R{sub n}, n{>=}2. Bibliography: 18 titles.

Karimov, Ruslan Kh [Institute of Applied Research, Sterlitamak (Russian Federation); Kozhevnikova, Larisa M [Sterlitamak State Pedagogical Academy, Sterlitamak (Russian Federation)

2010-11-11T23:59:59.000Z

343

The relative isoperimetric inequality on a conformally parabolic manifold with boundary  

SciTech Connect

For an arbitrary noncompact n-dimensional Riemannian manifold with a boundary of conformally parabolic type it is proved that there exists a conformal change of metric such that a relative isoperimetric inequality of the same form as in the closed n-dimensional Euclidean half-space holds on the manifold with the new metric. This isoperimetric inequality is asymptotically sharp. Bibliography: 6 titles.

Kesel'man, Vladimir M [Moscow State Industrial University, Moscow (Russian Federation)

2011-07-31T23:59:59.000Z

344

Heat Transfer Analysis and Modeling of a Parabolic Trough Solar Receiver Implemented in Engineering Equation Solver  

DOE Green Energy (OSTI)

This report describes the development, validation, and use of a heat transfer model implemented in Engineering Equation Solver. The model determines the performance of a parabolic trough solar collector's linear receiver, also called a heat collector element. All heat transfer and thermodynamic equations, optical properties, and parameters used in the model are discussed. The modeling assumptions and limitations are also discussed, along with recommendations for model improvement.

Forristall, R.

2003-10-01T23:59:59.000Z

345

LINSOL: a model for predicting the optical performance of parabolic trough solar thermal systems  

DOE Green Energy (OSTI)

A detailed model has been developed to predict the optical performance of parabolic trough solar energy systems. The model is one to two orders of magnitude faster than previous, less complete calculations and makes tractable investigation of a wide range of design and application alternatives for trough systems. Representative results are presented that show the dependence of the trough optical performance on field orientation and site latitude.

Dellin, T.A.

1981-01-01T23:59:59.000Z

346

Dielectric compound parabolic concentrating solar collector with a frustrated total internal reflection absorber  

SciTech Connect

Coupling a dielectric compound parabolic concentrator (DCPC) to an absorber across a vacuum gap by means of frustrated total internal reflection (FTIR) can theoretically approach the maximum concentration permitted by physical laws, thus allowing higher radiative fluxes in thermal applications. The calculated optical performance of 2-D DCPCs with FTIR absorbers indicates that the ratio of gap thickness to optical wavelength must be /0.22 before the optical performance of the DCPC is superior to that of the nondielectric CPC.

Hull, J.R.

1989-01-01T23:59:59.000Z

347

Dielectric compound parabolic concentrating solar collector with frustrated total internal reflection absorber  

SciTech Connect

Since its introduction, the concept of nonimaging solar concentrators, as exemplified by the compound parabolic concentrator (CPC) design, has greatly enhanced the ability to collect solar energy efficiently in thermal and photovoltaic devices. When used as a primary concentrator, a CPC can provide significant concentration without the complication of a tracking mechanism and its associated maintenance problems. When used as a secondary, a CPC provides higher total concentration, or for a fixed concentration, tolerates greater tracking error in the primary.

Hull, J.R.

1988-01-01T23:59:59.000Z

348

Investigation on the prediction of thermal performance of compound parabolic concentrators  

SciTech Connect

The present paper focuses attention on the prediction of thermal performance of a compound parabolic concentrator for different values of insolation and mass flow rate of collector medium (water), under steady-state conditions. The analysis involves an iterative scheme and a method is proposed by which the absorber temperature, outlet temperature and glazing temperature can be predicted for given insolation and mass flow rate. 4 refs.

Hariprasad, C.R.; Natarajan, R.; Gupta, M.C.

1981-01-01T23:59:59.000Z

349

LED Lighting  

Energy.gov (U.S. Department of Energy (DOE))

Light-emitting diodes (LEDs) are light sources that differ from more traditional sources of light in that they are semiconductor devices that produce light when an electrical current is applied....

350

Sulfur Lamps-The Next Generation of Efficient Light?  

NLE Websites -- All DOE Office Websites (Extended Search)

5 5 Sulfur Lamps-The Next Generation of Efficient Light? The figure above is a schematic of the system installed at the National Air and Space Museum and the DOE headquarters in Washington, D.C., Light from the sulfur lamp is focused by a parabolic reflector so that it enters the light pipe within a small angular cone. Light travels down the pipe, reflecting off the prismatic film (A) that lines the outer acrylic tube. The prismatic film reflects the light through total internal reflection (C), an intrinsically efficient process. Some of the light striking the film (at A) is not reflected and "leaks out" of the pipe walls (B), giving the pipe a glowing appearance. A light ray that travels all the way down the pipe will strike the mirror at the end (D) and return back up the pipe.

351

Energetic protons from an ultraintense laser interacting with a symmetric parabolic concave target  

SciTech Connect

A scheme of a symmetric parabolic concave target irradiated by an ultraintense laser for efficient proton acceleration is proposed and involved problem is studied by using two-dimensional particle-in-cell (PIC) simulations. Results indicate that on one hand, the laser field is focused by the front parabolic concave surface of target and, on the other hand, more energetic hot electrons will traverse to the rear surface of target due to concave shape. The space-charge-separation field, induced by those hot electrons escaping form parabolic concave rear surface of target, can accelerate protons to relatively high energy with narrow energy spread. The dependence of the efficiency of proton acceleration on the target parameters is examined, and the optimal target parameters are obtained. Particle-in-cell simulations show that the proton peak energy and energy spread are greatly enhanced when the target parameters are chosen optimal, for example, a proton bunch with the maximum energy {approx}27.5 MeV and energy spread {approx}7% can be generated. Some implications of our results to experiments and comparisons with the other works are also discussed briefly.

Ali Bake, Muhammad; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

2013-03-15T23:59:59.000Z

352

Task analysis for solar installers  

SciTech Connect

The process focused on the sequential identification and field validation of the tasks actually performed. This method provides an accurate picture of what happens on the roof. Forty-six solar firms were identified as the population; 29 (63%) participated in the validation project. We identified 8 duty areas and 46 tasks. The overall response rate for the occupational task list is 100% except for tasks under the duty of constructing solar collectors. Only eight of the twenty-nine respondents (28%) indicated that solar installers fabricate collectors. This shows that solar installers do not manufacture collectors and only perform tasks directly related to installation. Additional findings from our study indicate that instructional materials designed for solar installers need to be standardized and made task-specific. The tasks identified in this research should form the foundation for a competency-based curriculum for solar water heater installers.

Harrison, J.; LaHart, D.

1982-01-01T23:59:59.000Z

353

488 Brazilian Journal of Physics, vol. 36, no. 2A, June, 2006 Spin Valve Effect and Hall Resistance in a Wide Parabolic Well  

E-Print Network (OSTI)

in a Wide Parabolic Well C. A. Duarte, G. M. Gusev, A. A. Quivy, and T. E. Lamas Instituto de F´isica da observation of the Hall slope change in wide AlcGa1-cAs parabolic wells in the presence of a quasi on the electron density; it is observed only in parabolic wells, which are almost completely filled by electrons

Gusev, Guennady

354

Lighting Techniques  

Science Conference Proceedings (OSTI)

...Lighting is very critical in photography. The specimen should be placed on a background which will not detract from the resolution of the fracture surface. For basic lighting, one spotlight is suggested. The light is then raised or lowered, and

355

Performance and testing of a stationary concentrating collector. [Compound parabolic concentrators coupled to tubular evacuated receivers  

DOE Green Energy (OSTI)

The development of nonimaging solar collectors for heating and cooling applications is reported. A totally stationary concentrating collector has been designed, built, and tested. The collectors employ compound parabolic concentrators coupled to tubular evacuated receivers. Performance of the collector is substantially better than flat plate collectors, and the collectors are suitable for powering mechanically driven air conditioning systems as well as conventional absorption cycle machines. This collector concept was awarded an IR-100 award by Industrial Research Magazine as one of the 100 most significant new developments in 1977.

Cole, R L; Allen, J W; Levitz, N M; McIntire, W R; Schertz, W W

1977-01-01T23:59:59.000Z

356

Omnium-G parabolic dish optical efficiency: a comparison of two independent measurement techniques  

DOE Green Energy (OSTI)

Measurements made at SERI of the optical efficiency of the Omnium-G parabolic dish concentrator are described. Two independent techniques were used: the cold-water calorimeter method and the heat of fusion method. Results from both techniques agree quite well and indicate that the optical efficiency for a 10-cm receiver aperture is 25%. Optical efficiency measured in early 1979 was 37%, and in mid 1979 it had degraded to 21%. An optical alignment procedure is described that resulted in the increase in optical efficiency from 21% to the current value of 25%.

Bohn, M.; Gaul, H.

1980-10-01T23:59:59.000Z

357

Analytical Approach Treating Three-Dimensional Geometrical Effects of Parabolic Trough Collectors: Preprint  

DOE Green Energy (OSTI)

An analytical approach, as an extension of one newly developed method -- First-principle OPTical Intercept Calculation (FirstOPTIC) -- is proposed to treat the geometrical impact of three-dimensional (3-D) effects on parabolic trough optical performance. The mathematical steps of this analytical approach are presented and implemented numerically as part of the suite of FirstOPTIC code. In addition, the new code has been carefully validated against ray-tracing simulation results and available numerical solutions. This new analytical approach to treating 3-D effects will facilitate further understanding and analysis of the optical performance of trough collectors as a function of incidence angle.

Binotti, M.; Zhu, G.; Gray, A.; Manzollini, G.

2012-04-01T23:59:59.000Z

358

Initial evolution of supports of solutions of quasilinear parabolic equations with degenerate absorption potential  

SciTech Connect

The propagation of supports of solutions of second-order quasilinear parabolic equations is studied; the equations are of the type of nonstationary diffusion, having semilinear absorption with an absorption potential which degenerates on the initial plane. We find sufficient conditions, which are sharp in a certain sense, on the relationship between the boundary regime and the type of degeneration of the potential to ensure the strong localization of solutions. We also establish a weak localization of solutions for an arbitrary potential which degenerates only on the initial plane. Bibliography: 12 titles.

Stepanova, Ekaterina V; Shishkov, Andrey E

2013-03-31T23:59:59.000Z

359

The Cauchy problem for a quasilinear parabolic equation with gradient absorption  

SciTech Connect

The qualitative properties of solutions to the Cauchy problem for a degenerate parabolic equation containing a nonlinear operator of Baouendi-Grushin type and with gradient absorption whose density depends on time, as well as the space variables, are investigated. Bounds for the diameter of the support of the solution which are sharp with respect to time are obtained, together with its maximum. A condition which determines whether or not the phenomenon of decay to zero of the total mass of the solution occurs is discovered. Bibliography: 35 titles.

Markasheva, Vera A; Tedeev, Anatoli F [Institute of Applied Mathematics and Mechanics, Ukraine National Academy of Sciences, Donetsk (Ukraine)

2012-04-30T23:59:59.000Z

360

Proceedings: fourth parabolic-dish solar-thermal power program review  

DOE Green Energy (OSTI)

The primary objective of the review was to present the results of activities within the Parabolic Dish Technology and Applications Development element of the Department of Energy's Solar Thermal Energy Systems Program. The Review consisted of 6 technical sessions, covering Stirling, Organic Rankine and Brayton module technologies, associated hardware and test results to date; concentrator development and progress; economic analyses; and current international dish development activities. Two panel discussions, concerning industry issues affecting solar thermal dish development and dish technology from a utility/user perspective, were also held. These Proceedings contain the texts of presentations made at the review, which are abstracted separately for EDB.

Not Available

1983-02-01T23:59:59.000Z

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


361

Frequency response analysis of fluid control systems for parabolic-trough solar collectors  

DOE Green Energy (OSTI)

A linearized steady-state frequency response is derived for parabolic-trough collectors and for connecting piping that can be used in standard gain-phase analyses to evaluate system stability and closed-loop frequency response. The frequency-response characteristics of a typical collector string and piping are used in a gain-phase analysis to get some insight into the effect on system stability of various system parameters such as controller gain, sensor and controller-time constants, and sensor location.

Schindwolf, R.

1981-07-01T23:59:59.000Z

362

Measured performances of curved inverted-vee, absorber compound parabolic concentrating solar-energy collectors  

SciTech Connect

The design and thermal performance of modified compound parabolic concentrating (CPC) solar-energy collectors are described. The designs incorporate a curved inverted-Vee absorber fin, which allows a reflector of simple geometry to be used. This CPC collector, has exhibited a superior performance to that of a conventional cusp-reflector CPC design, owing to the enhancement of the optical efficiency obtained by eliminating gap optical losses and an enhanced heat removal factor. The consequence upon the performance of a further design refinement, which inhibited the convective heat losses, is also reported.

Norton, B. (Univ. of Ulster at Jordanstown (Ireland)); Prapas, D.E. (Aristotle Univ. of Thessaloniki (Greece)); Eames, P.C.; Probert, S.D. (Cranfield Institute of Technology, Bedford (England))

1989-01-01T23:59:59.000Z

363

The performance of bifacial solar cells in prism-coupled compound parabolic concentrators  

SciTech Connect

Fixed compound parabolic concentrators that couple radiation to solar cells through a prism-shaped dielectric medium were matched to bifacial solar cell arrays. Measures of annual-average short-circuit current output relative to the output with conventional panel operation of the arrays gave optical gains of approximately four times with symmetrical but simulated bifacial arrays and approximately three times with the asymmetrical Westinghouse bifacial arrays. When passive thermosyphon cooling was provided, the power gains measured at peak solar intensity were similar to the optical gains.

Edmonds, I.R. (Queensland Univ. of Technology, Brisbane (Australia))

1992-01-01T23:59:59.000Z

364

Analysis of the incidence angle of the beam radiation on CPC. [Compound Parabolic Concentrator  

SciTech Connect

Analytic expressions have been derived for the projected incidence angles {var theta}{sub 1} and {var theta}{sub 2} from a two-dimensional compound parabolic concentrator solar collector. For a CPC the fraction of the incident rays on the aperture at angle {var theta}, which reaches the absorber, depends only on the {var theta}{sub 1} angle. In this paper, a mathematical expression for {var theta}{sub 1} and {var theta}{sub t} has been calculated to determine the times at which acceptance of the sun's beam radiation begins and ceases for a CPC consisting of arbitrary orientation.

Pinazo, J.M.; Canada, J.; Arago, F. (Univ. Politecnica de Valencia (Spain))

1992-09-01T23:59:59.000Z

365

An experimental study of free convection in compound parabolic concentrator (CPC) cavities  

SciTech Connect

An experimental study of the free convection heat transfer between the cylindrical absorber and the flat top of a compound parabolic concentrator (CPC) is described. Results are obtained for a range of absorber temperatures and four CPC cavity heights. For similar conditions of operating temperature, the heat transfer from a cylinder in free air is about 30 to 50 percent higher than in a CPC cavity. Two correlations for Nusselt and Grashof numbers have been obtained using the equivalent length and the cavity height as the characteristic length of the system.

Chew, T.C.; Wijeysundera, N.E.; Tay, A.O.

1988-11-01T23:59:59.000Z

366

Development effort on sheet-molding compound (SMC) parabolic-trough panels  

SciTech Connect

The approach taken to develop integrally molded reflective glass with sheet molding compound into parabolic trough solar reflectors is described in detail. Results indicate that mirrored glass sheets, if properly strengthened to withstand the temperature and pressure of the molding process, can be successfully molded with sheet molding compound in a single press stroke using standard compression molding techniques. The silver reflective surface must be coated with an adhesive mixture that provides both protection of the silver and adhesion to the sheet molding compound. The sheet molding compound must provide the strength and stiffness required of a structure backing material. (LEW)

Kirsch, P.A.

1982-07-01T23:59:59.000Z

367

EPRI Transformer Task Force Proceedings  

Science Conference Proceedings (OSTI)

The EPRI Transformer Task Force held a meeting on December 4, 2007, in San Antonio, Texas. This technical update contains the proceedings of the meeting.

2008-02-12T23:59:59.000Z

368

EPRI Transformer Task Force Proceedings  

Science Conference Proceedings (OSTI)

This report contains the proceedings from the EPRI Transformers Task Force, which was held in Montreal on October 26 and 27, 2006.

2006-12-12T23:59:59.000Z

369

Army Energy Initiatives Task Force  

Energy.gov (U.S. Department of Energy (DOE))

Presentation—given at the Fall 2011 Federal Utility Partnership Working Group (FUPWG) meeting—covers the Army Energy Initiatives Task Force.

370

Lighting Group: Light Distribution Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Retrofit Alternatives to Incandescent Downlights Hotel and Institutional Bathroom Lighting Portable Office Lighting Systems Low Glare Outdoor Retrofit Luminaire LED Luminaires...

371

Lighting Research Center Lighting Products  

Science Conference Proceedings (OSTI)

... 12) Solid State Lighting Luminaires - Color Characteristic Measurements. [22/S04] IES LM-16:1993 Practical Guide to Colorimetry of Light Sources. ...

2013-07-26T23:59:59.000Z

372

Outlaw lighting  

SciTech Connect

Demand-side management programs by utilities and the federal government`s Green Lights program have made significant inroads in promoting energy-efficient lighting. But the Energy Policy Act now prohibits certain types of lighting. This article provides analysis to help architects determine new lamp performance compared with older lighting products.

Bryan, H.

1994-12-01T23:59:59.000Z

373

Incandescent Lighting | Department of Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

or pear-shaped A-19 lamps Energy-saving or halogen A-19 lamps Reflector or parabolic reflector (PAR) lamps, sometimes called "flood" or "spot" lamps Standard...

374

Measurement of Hydrogen Purge Rates in Parabolic Trough Receiver Tubes: Preprint  

SciTech Connect

The purpose of this research is to investigate and develop methods to remove hydrogen centrally from commercial parabolic trough power plants. A mathematical model was developed that tracks the generation and transport of hydrogen within an operating plant. Modeling results predicted the steady-state partial pressure of hydrogen within the receiver annuli to be ~1 torr. This result agrees with measured values for the hydrogen partial pressure. The model also predicted the rate at which hydrogen must be actively removed from the expansion tank to reduce the partial pressure of hydrogen within the receiver annuli to less than 0.001 torr. Based on these results, mitigation strategies implemented at operating parabolic trough power plants can reduce hydrogen partial pressure to acceptable levels. Transient modeling predicted the time required to reduce the hydrogen partial pressures within receiver annuli to acceptable levels. The times were estimated as a function of bellows temperature, getter quantity, and getter temperature. This work also includes an experimental effort that will determine the time required to purge hydrogen from a receiver annulus with no getter.

Glatzmaier, G. C.

2010-10-01T23:59:59.000Z

375

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish  

DOE Green Energy (OSTI)

The concept of solar driven chemical reactions in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH{sub 4}) with carbon dioxide (CO{sub 2}) was achieved in a 64-cm diameter direct absorption reactor on a parabolic dish capable of 150 kW solar power. The reactor was a catalytic volumetric absorber consisting of a multi-layered, porous alumina foam disk coated with rhodium (Rh) catalyst. The system was operated during both steady-state and solar transient (cloud passage) conditions. The total solar power absorbed reached values up to 97 kW and the maximum methane conversion was 70%. Receiver thermal efficiencies ranged up to 85% and chemical efficiencies peaked at 54%. The absorber performed satisfactorily in promoting the reforming reaction during the tests without carbon formation. However, problems of cracking and degradation of the porous matrix, nonuniform dispersion of the Rh through the absorber, and catalyst deactivation due to sintering and possible encapsulation, must be resolved to achieve long-term operation and eventual commercialization. 17 refs., 11 figs., 1 tab.

Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. (Sandia National Labs., Albuquerque, NM (USA)); Buck, R. (Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany, F.R.). Inst. fuer Technische Thermodynamik)

1990-01-01T23:59:59.000Z

376

Convection heat loss from cavity receiver in parabolic dish solar thermal power system: A review  

SciTech Connect

The convection heat loss from cavity receiver in parabolic dish solar thermal power system can significantly reduce the efficiency and consequently the cost effectiveness of the system. It is important to assess this heat loss and subsequently improve the thermal performance of the receiver. This paper aims to present a comprehensive review and systematic summarization of the state of the art in the research and progress in this area. The efforts include the convection heat loss mechanism, experimental and numerical investigations on the cavity receivers with varied shapes that have been considered up to date, and the Nusselt number correlations developed for convection heat loss prediction as well as the wind effect. One of the most important features of this paper is that it has covered numerous cavity literatures encountered in various other engineering systems, such as those in electronic cooling devices and buildings. The studies related to those applications may provide valuable information for the solar receiver design, which may otherwise be ignored by a solar system designer. Finally, future development directions and the issues that need to be further investigated are also suggested. It is believed that this comprehensive review will be beneficial to the design, simulation, performance assessment and applications of the solar parabolic dish cavity receivers. (author)

Wu, Shuang-Ying; Xiao, Lan; Li, You-Rong [College of Power Engineering, Chongqing University, Chongqing 400044 (China); Cao, Yiding [Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174 (United States)

2010-08-15T23:59:59.000Z

377

Nomographic methodology for use in performance trade-off studies of parabolic dish solar power modules  

DOE Green Energy (OSTI)

A simple graphical method has been developed to undertake technical design trade-off studies for individual parabolic dish modules comprising a two-axis tracking parabolic dish with a cavity receiver and power conversion assembly at the focal point. The results of these technical studies can then be used in performing the techno-economic analyses required for determining appropriate subsystem sizing. Selected graphs that characterize the performance of subsystems within the module have been arranged in the form of a nomogram that would enable an investigator to carry out several design trade-off studies. Key performance parameters encompassed in the nomogram include receiver losses, intercept factor, engine rating, and engine efficiency. Design and operation parameters such as concentrator size, receiver type (open or windowed aperture), receiver aperture size, operating temperature of the receiver and engine, engine partial load characteristics, concentrator slope error, and the type of reflector surface, are also included in the graphical solution. Cost considerations are not included. The nomogram has been used to perform trade-off studies that have provided a basis for determining requirements for a single concentrator that could perform satisfactorily with either the selected Stirling or Brayton engine. This activity is summarized to illustrate the usage of the nomogram. Additionally, modeling relations used in developing the nomogram are presented so that the nomogram can be updated to reflect any changes in the performance characteristics of projected components.

Selcuk, M. K.; Fujita, T.

1984-06-15T23:59:59.000Z

378

Water Use in Parabolic Trough Power Plants: Summary Results from WorleyParsons' Analyses  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory (NREL) contracted with WorleyParsons Group, Inc. to examine the effect of switching from evaporative cooling to alternative cooling systems on a nominal 100-MW parabolic trough concentrating solar power (CSP) plant. WorleyParsons analyzed 13 different cases spanning three different geographic locations (Daggett, California; Las Vegas, Nevada; and Alamosa, Colorado) to assess the performance, cost, and water use impacts of switching from wet to dry or hybrid cooling systems. NREL developed matching cases in its Solar Advisor Model (SAM) for each scenario to allow for hourly modeling and provide a comparison to the WorleyParsons results.Our findings indicate that switching from 100% wet to 100% dry cooling will result in levelized cost of electricity (LCOE) increases of approximately 3% to 8% for parabolic trough plants throughout most of the southwestern United States. In cooler, high-altitude areas like Colorado's San Luis Valley, WorleyParsons estimated the increase at only 2.5%, while SAM predicted a 4.4% difference. In all cases, the transition to dry cooling will reduce water consumption by over 90%. Utility time-of-delivery (TOD) schedules had similar impacts for wet- and dry-cooled plants, suggesting that TOD schedules have a relatively minor effect on the dry-cooling penalty.

Turchi, C. S.; Wagner, M. J.; Kutscher, C. F.

2010-12-01T23:59:59.000Z

379

An optimized model and test of the China's first high temperature parabolic trough solar receiver  

SciTech Connect

The vacuum solar receiver is the key component of a parabolic trough solar plant, which plays a prominent role in the gross system efficiency. Recently, China's first high temperature vacuum receiver, Sanle-3 HCE, has been developed and produced by Southeast University and Sanle Electronic Group. Before being utilized in China's first parabolic trough solar plant, accurately estimating the thermal properties of this new receiver is important. This paper first establishes and optimizes a 1-D theoretical model at Matlab program to compute the receiver's major heat loss through glass envelope, and then systematically analyzes the major influence factors of heat loss. With the laboratorial steady state test stand, the heat losses of both good vacuum and non-vacuum Sanle-3 receivers were surveyed. Comparison shows the original 1-D model agrees with the ends covered test while remarkably deviating from end exposed test. For the purpose of identifying the influence of receiver's end to total heat loss, an additional 3-D model is built by CFD software to further investigate the different heat transfer processes of receiver's end components. The 3-D end model is verified by heating power and IR temperature distribution images in the test. Combining the optimized 1-D model with the new 3-D end model, the comparison with test data shows a good accordance. At the same time the heat loss curve and emittance curve of this new receiver are given and compared with those of several other existing receivers as references. (author)

Gong, Guangjie; Huang, Xinyan; Wang, Jun; Hao, Menglong [Southeast University, Nanjing (China)

2010-12-15T23:59:59.000Z

380

Wind loads on heliostats and parabolic dish collectors: Final subcontractor report  

DOE Green Energy (OSTI)

A major intent of this study was to define wind load reduction factors for parabolic dish solar collectors within a field protected by upwind collectors, wind protective fences, or other blockages. This information will help researchers improve the economy of parabolic collector support structures and drive mechanisms. The method used in the study was to generalize wind load data obtained during tests on model collectors placed in a modeled atmospheric wind in a boundary-layer wind tunnel. A second objective of the study was to confirm and document a sensitivity in load to level of turbulence, or gustiness, in the approaching wind. A key finding was that wind-load reduction factors for forces (horizontal and vertical) were roughly similar to those for flat heliostats, with some forces significantly less than those for flat shapes. However, load reductions for moments showed a smaller load reduction, particularly for the azimuth moment. The lack of load reduction could be attributed to collector shape, but specific flow features responsible for and methods to induce a load reduction were not explored. 62 figs., 13 tabs.

Peterka, J.A.; Tan, Z.; Bienkiewicz, B.; Cermak, J.E.

1988-11-01T23:59:59.000Z

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


381

Material and process screening as applied to a reinforced plastic parabolic trough concentrator module  

DOE Green Energy (OSTI)

Existing parabolic trough solar collectors are basically sheet metal designs utilizing aluminum or steel as the major structural materials. The relatively high labor content associated with these sheet metal designs has generated an interest in investigating the cost effectiveness of using reinforced plastics as a major structural material for trough solar collectors. This interest is bolstered by a growing desire on the part of industry to identify new material-process combinations which save weight, use less energy, and require less capital equipment and assembly costs. The use of reinforced plastics as the basic material for a line-focus parabolic trough concentrator module is studied. This module constitutes a basic building block with which longer trough rows can be built. The basic part analysis is described including the quantification of key material and part-function relationships. In addition candidate materials and processes are reviewed and, the costs associated with the most attractive combinations defined. Finally, the major conclusions and recommendations are summarized.

Hodge, R. (ed.)

1980-08-01T23:59:59.000Z

382

Well-posedness of a parabolic moving-boundary problem in the setting of Wasserstein gradient flows  

E-Print Network (OSTI)

We develop a gradient-flow framework based on the Wasserstein metric for a parabolic moving-boundary problem that models crystal dissolution and precipitation. In doing so we derive a new weak formulation for this moving-boundary problem and we show that this formulation is well-posed. In addition, we develop a new uniqueness technique based on the framework of gradient flows with respect to the Wasserstein metric. With this uniqueness technique, the Wasserstein framework becomes a complete well-posedness setting for this parabolic moving-boundary problem.

Jacobus W. Portegies; Mark A. Peletier

2008-12-06T23:59:59.000Z

383

Category:Articles with outstanding TODO tasks | Open Energy Information  

Open Energy Info (EERE)

Articles with outstanding TODO tasks Articles with outstanding TODO tasks Jump to: navigation, search This category contains articles which have been flagged as requiring specific work. For higher-level TODO tasks which are not tied to specific articles, see OpenEI:TODO. Pages in category "Articles with outstanding TODO tasks" The following 177 pages are in this category, out of 177 total. 1 1st Light Energy, Inc. A A2BE Carbon Capture LLC Abbotsford, Australia Agricultural Equipment Ambient Control Systems American Solar Technology Amur Energy Division Anaerobic Digestion Anant Oorja Argonne, Illinois Askja Energy Austin Clean Energy Group B Bank of Italy Biodiesel Black Warrior, Nevada Boilers Boots on the Roof Bordeaux International Energy Consulting, LLC BP Statistical Review of World Energy

384

New and Underutilized Technology: Interior LED/Solid State Lighting |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Interior LED/Solid State Lighting Interior LED/Solid State Lighting New and Underutilized Technology: Interior LED/Solid State Lighting October 4, 2013 - 4:53pm Addthis The following information outlines key deployment considerations for interior LED/solid state lighting within the Federal sector. Benefits Interior LED retrofits are currently viable for down lights, track lighting, sconces, and both line and low voltage task lighting. Replacements for incandescent A-lamps have also been improving rapidly. Replacements for fluorescent tube lighting may be viable for high-cost maintenance areas. Application Interior LED/solid state lighting is a rapidly improving technology currently most applicable for down lights, track lights, task lighting, accenting, high ceiling, and high cost maintenance areas.

385

Enhanced Hall slope in wide AlxGax-1As parabolic wells A. M. Ortiz de Zevallos, N. C. Mamani, G. M. Gusev, A. A. Quivy, and T. E. Lamas  

E-Print Network (OSTI)

Enhanced Hall slope in wide AlxGax-1As parabolic wells A. M. Ortiz de Zevallos, N. C. Mamani, G. M report measurements of the Hall effect in 1000­4000 � wide AlxGax-1As parabolic wells with quasi- two resistance for wide parabolic wells is found to be enhanced when the temperature decreases. We attribute

Gusev, Guennady

386

Lighting Controls  

NLE Websites -- All DOE Office Websites (Extended Search)

corridors. The overall range of savings was six to 80 percent. The Advanced Lighting Guidelines On-Line Edition New Buildings Institute 2011 presents a table of lighting energy...

387

Security tasks are highly interdependent.  

E-Print Network (OSTI)

Motivation Security tasks are highly interdependent. To improve security tools, we need to understand how security practitioners collaborate in their organizations. Security practitioners in context Exchange of Information Develop security tools that: · Integrate information from different communication

388

An Efficient Hybrid Parabolic Equation --- Integral Equation Method for the Analysis of Wave Propagation in Highly Complex Indoor Communication Environments  

Science Conference Proceedings (OSTI)

An efficient, full-wave computational technique to investigate the electromagnetic wave propagation within a complex building environment, resulting from contemporary indoor communication systems, is proposed. Unlike a standard ray-tracing technique, ... Keywords: indoor communications, integral equations, parabolic equation, ray-tracing, wave propagation

G. K. Theofilogiannakos; T. V. Yioultsis; T. D. Xenos

2007-10-01T23:59:59.000Z

389

Study on the Principle and Technology of Coal and Methane Simultaneous Extraction Based on the Mining Fissure Elliptic Parabolic Zone  

Science Conference Proceedings (OSTI)

Coal and coal-bed methane are all valuable energy resource, if they can be extracted simultaneously and safely, the triple purposes of mine safety production, new energy resource supply and environment protection can be fulfilled. The coal-bed methane ... Keywords: Mining induced fissure, Elliptic Parabolic Zone, Relieved methane, Coal, methane simultaneous extraction

Lin Haifei; Li Shugang; Cheng Lianhua; Pan Hongyu

2011-02-01T23:59:59.000Z

390

Survey of Thermal Storage for Parabolic Trough Power Plants; Period of Performance: September 13, 1999 - June 12, 2000  

DOE Green Energy (OSTI)

The purpose of this report is to identify and selectively review previous work done on the evaluation and use of thermal energy storage systems applied to parabolic trough power plants. Appropriate storage concepts and technical options are first discussed, followed by a review of previous work.

Pilkington Solar International GmbH

2000-09-29T23:59:59.000Z

391

P-adic Elliptic Quadratic Forms, Parabolic-Type Pseudodifferential Equations With Variable Coefficients, and Markov Processes  

E-Print Network (OSTI)

In this article we study the Cauchy problem for a new class of parabolic-type pseudodifferential equations with variable coefficients for which the fundamental solutions are transition density functions of Markov processes in the four dimensional vector space over the field of p-adic numbers.

O. F. Casas-Sánchez; W. A. Zúńiga-Galindo

2013-11-29T23:59:59.000Z

392

Eyelid and eyelash detection method in the normalized iris image using the parabolic Hough model and Otsu's thresholding method  

Science Conference Proceedings (OSTI)

Eyelids and eyelashes occluding the iris region are noise factors that degrade the performance of iris recognition. If they are incorrectly classified as an iris region, the false iris region information decreases the recognition rate. Thus, reliable ... Keywords: Eyelash detection, Eyelid detection, Iris recognition, Parabolic Hough model, Thresholding

Tae-Hong Min; Rae-Hong Park

2009-09-01T23:59:59.000Z

393

A work-stealing scheduler for X10's task parallelism with suspension  

Science Conference Proceedings (OSTI)

The X10 programming language is intended to ease the programming of scalable concurrent and distributed applications. X10 augments a familiar imperative object-oriented programming model with constructs to support light-weight asynchronous tasks as well ... Keywords: X10, scheduling, task parallelism, work-stealing

Olivier Tardieu; Haichuan Wang; Haibo Lin

2012-02-01T23:59:59.000Z

394

Precise asymptotics for the parabolic Anderson model with a moving catalyst or trap  

E-Print Network (OSTI)

We consider the solution $u\\colon [0,\\infty) \\times\\mathbb{Z}^d\\rightarrow [0,\\infty) $ to the parabolic Anderson model, where the potential is given by $(t,x)\\mapsto\\gamma\\delta_{Y_t}\\left(x\\right)$ with $Y$ a simple symmetric random walk on $\\mathbb{Z}^d$. Depending on the parameter $\\gamma\\in[-\\infty,\\infty)$, the potential is interpreted as a randomly moving catalyst or trap. In the trap case, i.e., $\\gamma0$), we consider the solution $u$ from the perspective of the catalyst, i.e., the expression $u(t,Y_t+x)$. Focusing on the cases where moments grow exponentially fast (that is, $\\gamma$ sufficiently large), we describe the moment asymptotics of the expression above up to equivalence. Here, it is crucial to prove the existence of a principal eigenfunction of the corresponding Hamilton operator. While this is well-established for the first moment, we have found an extension to higher moments.

Schnitzler, Adrian

2010-01-01T23:59:59.000Z

395

STRESS ANALYSIS OF SPECIMENS FOR IN-PILE CREEP TESTS OF PARABOLIC GRAPHITE BEAMS  

SciTech Connect

The irradiation-induced creep of graphite is being investigated in experiments that consist of loading parabolically shaped cantilever beams at the free end and measuring the resulting deflections with time. A series of stress analyses was made to verify the applicability of the elementary strength-of- materials approach for obtaining relations between stress and creep strain from the load-deflection data. The results of the analyses, which included a theory- of-elasticity solution, an evaluation of the effect of shear, and a bending analysis using an actual stress-strain diagram for graphite, show that an elementary strength-of-materials approach is adequate to predict the initial or elastic stresses. Preliminary results from the in-pile experiments indicate that the creep strains are linear with stress; thus the initially linear bending stress distribution given by the elementary theory remains unchanged during creep. (auth)

Corum, J.M.

1964-02-01T23:59:59.000Z

396

Mixed finite-difference/integral transform approach for parabolic-hyperbolic problems in transient forced convection  

SciTech Connect

The integral transform method is employed in conjunction with second-order-accurate explicit finite-differences schemes, to handle accurately a class of parabolic-hyperbolic problems that appear in connection with transient forced convection inside ducts. The integral transformation process eliminates the independent variables in which the diffusion phenomena predominate. A system of coupled hyperbolic equations then results, involving time and the space coordinates in which convection is dominant, which is solved numerically through a modified upwind second-order finite-difference scheme. Stability and convergence characteristics of the proposed mixed approach are also examined. Typical applications in two- and three-dimensional geometries are considered, for both slug and laminar flow situations.

Cotta, R.M.; Gerk, J.E.V. (Univ. Federal do Rio de Janeiro (Brazil). Dept. de Engenharia Mecanica)

1994-06-01T23:59:59.000Z

397

Current and Future Costs for Parabolic Trough and Power Tower Systems in the US Market: Preprint  

DOE Green Energy (OSTI)

NREL's Solar Advisor Model (SAM) is employed to estimate the current and future costs for parabolic trough and molten salt power towers in the US market. Future troughs are assumed to achieve higher field temperatures via the successful deployment of low melting-point, molten-salt heat transfer fluids by 2015-2020. Similarly, it is assumed that molten salt power towers are successfully deployed at 100MW scale over the same time period, increasing to 200MW by 2025. The levelized cost of electricity for both technologies is predicted to drop below 11 cents/kWh (assuming a 10% investment tax credit and other financial inputs outlined in the paper), making the technologies competitive in the marketplace as benchmarked by the California MPR. Both technologies can be deployed with large amounts of thermal energy storage, yielding capacity factors as high as 65% while maintaining an optimum LCOE.

Turchi, C.; Mehos, M.; Ho, C. K.; Kolb, G. J.

2010-10-01T23:59:59.000Z

398

Utility-Scale Parabolic Trough Solar Systems: Performance Acceptance Test Guidelines, April 2009 - December 2010  

DOE Green Energy (OSTI)

Prior to commercial operation, large solar systems in utility-size power plants need to pass a performance acceptance test conducted by the engineering, procurement, and construction (EPC) contractor or owners. In lieu of the present absence of ASME or other international test codes developed for this purpose, the National Renewable Energy Laboratory has undertaken the development of interim guidelines to provide recommendations for test procedures that can yield results of a high level of accuracy consistent with good engineering knowledge and practice. The Guidelines contained here are specifically written for parabolic trough collector systems with a heat-transport system using a high-temperature synthetic oil, but the basic principles are relevant to other CSP systems.

Kearney, D.

2011-05-01T23:59:59.000Z

399

Frequency response analysis of fluid control systems for parabolic trough solar collectors  

DOE Green Energy (OSTI)

Previous studies of solar collector fluid control systems have utilized computer simulations of collector and piping dynamics to evaluate stability and response characteristics. To obtain reasonable simulation accuracy requires substantial computer memory and time, and is well beyond the capability of small desk-top computers. Here a linearized steady state frequency response is derived for parabolic trough collectors and for connecting piping, which can be used in standard gain-phase analyses to evaluate system stability and closed loop frequency response. The frequency response characteristics of a typical collector string and piping are used in a gain-phase analysis to get some insight into the effect on system stability of various system parameters such as controller gain, sensor and controller time constants, and sensor location.

Schindwolf, R.

1980-01-01T23:59:59.000Z

400

Current and future costs for parabolic trough and power tower systems in the US market.  

SciTech Connect

NREL's Solar Advisor Model (SAM) is employed to estimate the current and future costs for parabolic trough and molten salt power towers in the US market. Future troughs are assumed to achieve higher field temperatures via the successful deployment of low melting-point, molten-salt heat transfer fluids by 2015-2020. Similarly, it is assumed that molten salt power towers are successfully deployed at 100MW scale over the same time period, increasing to 200MW by 2025. The levelized cost of electricity for both technologies is predicted to drop below 11 cents/kWh (assuming a 10% investment tax credit and other financial inputs outlined in the paper), making the technologies competitive in the marketplace as benchmarked by the California MPR. Both technologies can be deployed with large amounts of thermal energy storage, yielding capacity factors as high as 65% while maintaining an optimum LCOE.

Turchi, Craig (National Renewable Energy Laboratory, Golden, CO); Kolb, Gregory J.; Mehos, Mark Steven (National Renewable Energy Laboratory, Golden, CO); Ho, Clifford Kuofei

2010-08-01T23:59:59.000Z

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


401

Analytic Q-ball solutions and their stability in a piecewise parabolic potential  

E-Print Network (OSTI)

Explicit solutions for extended objects of a Q-ball type were found analytically in a model describing complex scalar field with piecewise parabolic potential in (3+1)- and (1+1)-dimensional space-times. Such a potential provides a variety of solutions which were thoroughly examined. It was shown that, depending on the values of the parameters of the model and according to the known stability criteria, there exist stable and unstable solutions. The classical stability of solutions in (1+1)-dimensional space-time was examined in the linear approximation and it was shown explicitly that the spectrum of linear perturbations around some solutions contains exponentially growing modes while it is not so for other solutions.

I. E. Gulamov; E. Ya. Nugaev; M. N. Smolyakov

2013-03-05T23:59:59.000Z

402

THE STRUCTURE OF THE M87 JET: A TRANSITION FROM PARABOLIC TO CONICAL STREAMLINES  

SciTech Connect

The structure of the M87 jet, from milliarcsecond to arcsecond scales, is extensively investigated, utilizing the images taken with the European VLBI Network, MERLIN, and Very Long Baseline Array. We discover that the jet maintains a parabolic streamline over a range in size scale equal to 10{sup 5} times the Schwarzschild radius. The jet then transitions into a conical shape farther downstream. This suggests that the magnetohydrodynamic jet is initially subjected to the confinement by the external gas which is dominated by the gravitational influence of the supermassive black hole. Afterward the jet then freely expands with a conical shape. This geometrical transition indicates that the origin of the HST-1 complex may be a consequence of the overcollimation of the jet. Our result suggests that when even higher angular resolution is provided by a future submillimeter very long baseline interferometry experiments, we will be able to explore the origin of active galactic nucleus jets.

Asada, Keiichi; Nakamura, Masanori, E-mail: asada@asiaa.sinica.edu.tw, E-mail: nakamura@asiaa.sinica.edu.tw [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)

2012-02-15T23:59:59.000Z

403

Importance of non-parabolic band effects in the thermoelectric properties of semiconductors  

SciTech Connect

We present an analysis of the thermoelectric properties of of n-type GeTe and SnTe in relation to the lead chalcogenides PbTe and PbSe. We find that the singly degenerate conduction bands of semiconducting GeTe and SnTe are highly non-parabolic, even very close to the band edges. This leads to isoenergy surfaces with a strongly corrugated shape that is clearly evident at carrier concentrations well below 0.005 e per formula unit. Analysis within Boltzmann theory shows that this corrugation is favorable for the thermoelectric transport. As a result these materials may exhibit n-type performance exceeding that of the lead chalcogenides.

Singh, David J [ORNL] [ORNL; Parker, David S [ORNL] [ORNL; Chen, Xin [ORNL] [ORNL

2013-01-01T23:59:59.000Z

404

A 32 m Parabolic Antenna in Peru At 3,370m of Altitude  

E-Print Network (OSTI)

At the altitude of 3,370 m on the Peruvian Andes, a 32m antenna owned by the telecommunications company Telefonica del Peru will be transformed to a Radio Telescope, it would be transferred to the Geophysical Institute of Peru (IGP). The parabolic antenna was constructed in 1984 by Nippon Electric Co. (NEC) and worked as an INTELSAT station until 2000. A team of the National Observatory of Japan (NAOJ) evaluated the antenna in 2003 and reported its availability to be used as a Radio Telescope. In collaboration of the NAOJ a 6.7 GHz receiver is under construction and will be installed within this year. Initially the telescope as a single dish will monitor and survey Methanol Maser of YSO, higher frequencies equipment and VLBI instruments will be considered. The antenna will be managed by the IGP and used by universities in Peru, becoming a VLBI station will be a grate contribution to astronomy and geodetic community.

J. Ishitsuka; M. Ishitsuka; N. Kaifu; S. Miyama; M. Inoue; M. Tsuboi; M. Ohishi; K. Fujisawa; T. Kasuga; K. Miyazawa; S. Horiuchi

2005-01-04T23:59:59.000Z

405

Cleaning strategies for parabolic-trough solar-collector fields; guidelines for decisions  

DOE Green Energy (OSTI)

This report is intended to assist the owner or operator of a parabolic trough solar collector system to decide on a cleaning strategy (equipment, materials, procedures, and schedules). The guidelines are based on information obtained in past research studies, as well as interviews with vendors and users of cleaning and water treatment equipment. The basic procedure recommended utilizes high pressure portable washing equipment. However, since the cleaning problem is so site-specific, no single, detailed approach can be specified. A systematic procedure for evaluating the particular requirements of a site is therefore given. This will allow the solar energy system operator to develop a cleaning strategy which is cost-effective because it is suited to local conditions.

Bergeron, K.D.; Freese, J.M.

1981-06-01T23:59:59.000Z

406

Estimates in Generalized Morrey Spaces for Weak Solutions to Divergence Degenerate Parabolic Systems  

E-Print Network (OSTI)

Let $\\mathrm{X}=(X_{1},...,X_{q})$ be a family of real smooth vector fields satisfying H\\"{o}mander's condition. The purpose of this paper is to establish gradient estimates in generalized Morrey spaces for weak solutions of the divergence degenerate parabolic system related to $X$ :%\\[u_{t}^{i}+X_{\\alpha}^{\\ast}(a_{ij}^{\\alpha\\beta}(z)X_{\\beta}u^{j}%)=g_{i}+X_{\\alpha}^{\\ast}f_{i}^{\\alpha}(z), \\] where $\\alpha,\\beta=1,2,...,q,$ $i,j=1,2,...,N$, $X_{\\alpha}^{\\ast}$ is the transposed vector field of $X_{\\alpha}$, $z=(t,x)\\in{\\mathbb{R}}^{n+1}$, and coefficients $a_{ij}^{\\alpha\\beta}(z)$ belong to the space $VMO$ induced by the vector fields $X_{1}, ...,X_{q}$.

Dong, Yan; Niu, Pengcheng

2011-01-01T23:59:59.000Z

407

Experimental and raytrace results for throat-to-throat compound parabolic concentrators  

SciTech Connect

Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer.) We discuss the design of one pair of cones, an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

Leviton, D.B.; Leitch, J.W.

1986-08-15T23:59:59.000Z

408

Yearly distributed insolation model and optimum design of a two dimensional compound parabolic concentrator  

SciTech Connect

Optimum acceptance angle of a compound parabolic concentrator (CPC) is studied by the use of an insolation model proposed in this paper. The insolation consists of two components: diffuse and direct. The direct radiation is supposed to be distributed in the field within {+-}23.5{degree} of declination on the celestial hemisphere and the diffuse radiation is assumed to have uniform irradiance. This yearly insolation model suggests that the optimum half-acceptance angle at the two-dimensional CPC becomes 26{degree} irrespective of the change of the diffuse radiation fraction. This result leads us to the conclusion that, almost all over the world, a common CPC could be used as an optimum concentration for many solar radiation collecting systems. 11 refs., 8 figs.

Suzuki, Akio; Kobayashi, Shigeo [Tokyo Univ. of Agriculture and Technology (Japan)

1995-05-01T23:59:59.000Z

409

Design of light concentrators for Cherenkov telescope observatories  

E-Print Network (OSTI)

The Cherenkov Telescope Array (CTA) will be the largest cosmic gamma ray detector ever built in the world. It will be installed at two different sites in the North and South hemispheres and should be operational for about 30 years. In order to cover the desired energy range, the CTA is composed of typically 50-100 collecting telescopes of various sizes (from 6 to 24-m diameters). Most of them are equipped with a focal plane camera consisting of 1500 to 2000 Photomultipliers (PM) equipped with light concentrating optics, whose double function is to maximize the amount of Cherenkov light detected by the photo-sensors, and to block any stray light originating from the terrestrial environment. Two different optical solutions have been designed, respectively based on a Compound Parabolic Concentrator (CPC), and on a purely dioptric concentrating lens. In this communication are described the technical specifications, optical designs and performance of the different solutions envisioned for all these light concentra...

Hénault, F; jocou, L; Khélifi, B; Manigot, P; Hormigos, S; Knodlseder, J; Olive, J F; Jean, P; Punch, M

2013-01-01T23:59:59.000Z

410

Shape the light, light the shape - lighting installation in performance.  

E-Print Network (OSTI)

??This thesis investigates the lighting design theory Light Inside Out, which is the technique of shaping light toward a creation of lighting installation in performance… (more)

Yu, Lih-Hwa, 1972-

2010-01-01T23:59:59.000Z

411

Energy Conservation Utilizing Wireless Dimmable Lighting Control  

E-Print Network (OSTI)

Energy Conservation Utilizing Wireless Dimmable Lighting Control in a Shared-Space Office Yao preference and requirements vary · among individuals · with tasks · with time and age Lighting satisfaction occupants sharing an office? · Ethernet infrastructure How will the energy savings and user satisfaction

Agogino, Alice M.

412

Application of compound parabolic concentrators to solar photovoltaic conversion. Final report  

DOE Green Energy (OSTI)

The final results of an analytical and experimental study of the application of nonimaging concentrators to solar photovoltaic conversion are presented. Two versions of the Compound Parabolic Concentrator (CPC) were considered, the Dielectric Compound Parabolic Concentrator (DCPC) in which the concentrator is filled with a dielectric material that satisfies requirements for Total Internal Reflection (TIR), and a conventional CPC in which metallic reflection is used for the mirror surfaces. Two working prototype panels were constructed and tested during the course of the program. The first was a 1.22 m by 1.22 m DCPC panel that requires only ten adjustments/year, has a panel utilization factor (packing factor) of 96%, and delivered the equivalent of 138 W (peak) under 1 kW/m/sup 2/ direct insolation. The net energy conversion efficiency was 10.3% over the entire panel area. The second panel was a conventional CPC panel measuring 1.22 m by 1.22 m. This panel requires thirty-six adjustments per year, and delivers the equivalent of 97 W when under 1 kW/m/sup 2/ direct insolation. The results of a cost-effectiveness analysis of the concept of using nonimaging concentrators for photovoltaic conversion are also presented. The concentrator panels showed a decided savings in comparison to the cost of flat plate photovoltaic panels, both at present-day silicon costs ($2000/m/sup 2/) and projected lower silicon costs ($200/m/sup 2/). At a silicon cost of $200/m/sup 2/, a two-dimensional (cone) version of the collector has the potential for achieving from $0.60-2.00 per average watt (about $0.15-0.50 per peak watt) while requiring only crude (+-4.5/sup 0/) tracking.

Cole, R.L.; Gorski, A.J.; Graven, R.M.; McIntire, W.R.; Schertz, W.W.; Winston, R.; Zwerdling, S.

1977-02-01T23:59:59.000Z

413

Evaluating office lighting environments: Second-level analysis  

SciTech Connect

Data from a post-occupancy evaluation (POE) of 912 work stations with lighting power density (LPD), photometric, and occupant-response measures were examined in a detailed, second-level analysis. Seven types of lighting systems were identified with different combinations of direct and indirect ambient lighting, and task lighting and daylight. The mean illuminances at the primary task location were within the IES target values for office task with a range of mean illuminances from 32 to 75 fc, depending on the lighting system. The median LPD was about 2.36 watts/sq ft, with about one-third the work stations having LPD's at or below 2.0 watts/sq ft. Although a majority of the occupants (69%) were satisfied about their lighting, the highest percentage of those expressing dissatisfaction (37%) with lighting had an indirect fluorescent furniture-mounted (IFFM) system. The negative reaction of so many people to the IFFM system suggests that the combination of task lighting with an indirect ambient system had an important influence on lighting satisfaction, even though task illuminances tended to be higher with the IFFM system. Concepts of lighting quality, visual health, and control were explored, as well as average luminance to explain the negative reactions to the combination of indirect lighting with furniture-mounted lighting.

Collins, B.L.; Fisher, W.S.; Gillette, G.L.; Marans, R.W.

1989-04-01T23:59:59.000Z

414

Lighting Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Purple LED lamp Purple LED lamp Lighting Systems Lighting research is aimed at improving the energy efficiency of lighting systems in buildings and homes across the nation. The goal is to reduce lighting energy consumption by 50% over twenty years by improving the efficiency of light sources, and controlling and delivering illumination so that it is available, where and when needed, and at the required intensity. Research falls into four main areas: Sources and Ballasts, Light Distribution Systems, Controls and Communications, and Human Factors. Contacts Francis Rubinstein FMRubinstein@lbl.gov (510) 486-4096 Links Lighting Research Group Batteries and Fuel Cells Buildings Energy Efficiency Applications Commercial Buildings Cool Roofs and Heat Islands Demand Response Energy Efficiency Program and Market Trends

415

Task Force Approach | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Task Force Approach Task Force Approach Task Force Approach Task Force Approach Results of the ARI Task Force: The purpose of the ARI Task Force is to 1) identify, prioritize, and resolve issues to enable sites and programs to implement revitalization efforts more effectively and 2) to facilitate programmatic incorporation of revitalization concepts into DOE's programmatic business environments. The Task Force must do this through coordinating and facilitating communication and connections, sharing lessons learned, broadening the general knowledge base, facilitating, analyzing problems, developing implementable solutions, and considering and incorporating broader perspectives and knowledge. The success of the Task Force can be evaluated by impacts to the Department upon its completion. These impacts

416

Nuclear Radiological Threat Task Force Established | National...  

National Nuclear Security Administration (NNSA)

Force Established Nuclear Radiological Threat Task Force Established November 03, 2003 Washington, DC Nuclear Radiological Threat Task Force Established NNSA's Administrator...

417

The Pilot Study R&D Task  

Science Conference Proceedings (OSTI)

The Pilot Study R&D Task. EDT – a complex of four tasks: 1) Detection of Entities – limited to five types: PER ORG GPE ...

418

Commercial Lighting and LED Lighting Incentives  

Energy.gov (U.S. Department of Energy (DOE))

Incentives for energy efficient commercial lighting equipment as well as commercial LED lighting equipment are available to businesses under the Efficiency Vermont Lighting and LED Lighting...

419

Windows and lighting program  

SciTech Connect

More than 30% of all energy use in buildings is attributable to two sources: windows and lighting. Together they account for annual consumer energy expenditures of more than $50 billion. Each affects not only energy use by other major building systems, but also comfort and productivity -- factors that influence building economics far more than does direct energy consumption alone. Windows play a unique role in the building envelope, physically separating the conditioned space from the world outside without sacrificing vital visual contact. Throughout the indoor environment, lighting systems facilitate a variety of tasks associated with a wide range of visual requirements while defining the luminous qualities of the indoor environment. Windows and lighting are thus essential components of any comprehensive building science program. Despite important achievements in reducing building energy consumption over the past decade, significant additional savings are still possible. These will come from two complementary strategies: (1) improve building designs so that they effectively apply existing technologies and extend the market penetration of these technologies; and (2) develop advanced technologies that increase the savings potential of each application. Both the Windows and Daylighting Group and the Lighting System Research Group have made substantial contributions in each of these areas, and continue to do so through the ongoing research summarized here. 23 refs., 16 figs.

1990-06-01T23:59:59.000Z

420

Technology reviews: Lighting systems  

SciTech Connect

We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice for energy efficiency, ranging from individual components to more complex systems to general design strategies. The purpose of this task is to characterize lighting system in the state of the art in envelope and lighting technologies in order to identify those with promise for advanced integrated systems, with an emphasis on California commercial buildings. For each technology category, the following activities have been attempted to the extent possible: Identify key performance characteristics and criteria for each technology. Determine the performance range of available technologies. Identify the most promising technologies and promising trends in technology advances. Examine market forces and market trends. Develop a continuously growing in-house database to be used throughout the project. A variety of information sources have been used in these technology characterizations, including miscellaneous periodicals, manufacturer catalogs and cut sheets, other research documents, and data from previous computer simulations. We include these different sources in order to best show the type and variety of data available, however publication here does not imply our guarantee of these data. Within each category, several broad classes are identified, and within each class we examine the generic individual technologies that fall into that class.

Schuman, J.; Rubinstein, F.; Papamichael, K.; Beltran, L.; Lee, E.S.; Selkowitz, S.

1992-09-01T23:59:59.000Z

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


421

Northern Lights  

NLE Websites -- All DOE Office Websites (Extended Search)

Northern Lights Northern Lights Nature Bulletin No. 178-A February 6, 1965 Forest Preserve District of Cook County Seymour Simon, President Roland F. Eisenbeis, Supt. of Conservation NORTHERN LIGHTS To a person seeing the Aurora Borealis or "northern lights" for the first time, it is an uncanny awe-inspiring spectacle. Sometimes it begins as a glow of red on the northern horizon, ominously suggesting a great fire, gradually changing to a curtain of violet-white, or greenish-yellow light extending from east to west. Some times this may be transformed to appear as fold upon fold of luminous draperies that march majestically across the sky; sometimes as a vast multitude of gigantic flaming swords furiously slashing at the heavens; sometimes as a flowing crown with long undulating colored streamers fanning downward and outward.

422

A software measurement task ontology  

Science Conference Proceedings (OSTI)

Software measurement is a key process for software project management and software process improvement. There are several process quality models and measurement standards that point out its importance and present good practices for it. Unfortunately, ... Keywords: semantic interoperability, software measurement, task ontology

Monalessa Perini Barcellos; Ricardo de Almeida Falbo

2013-03-01T23:59:59.000Z

423

FAQS Job Task Analyses- Chemical Processing  

Energy.gov (U.S. Department of Energy (DOE))

FAQS Job Task Analyses are performed on the Function Area Qualification Standards. The FAQS Job Task Analyses consists of: Developing a comprehensive list of tasks that define the job such as the duties and responsibilities which include determining their levels of importance and frequency. Identifying and evaluating competencies. Last step is evaluating linkage between job tasks and competencies.

424

Prediction and optimization of the performance of parabolic solar dish concentrator with sphere receiver using analytical function  

E-Print Network (OSTI)

Parabolic solar dish concentrator with sphere receiver is less studied. We present an analytic function to calculate the intercept factor of the system with real sun bright distribution and Gaussian distribution, the results indicate that the intercept factor is related to the rim angle of reflector and the ratio of open angle of receiver at the top of reflector to optical error when the optical error is larger than or equal to 5 mrad, but is related to the rim angle, open angle and optical error in less than 5 mrad optical error. Furthermore we propose a quick process to optimize the system to provide the maximum solar energy to net heat efficiency for different optical error under typical condition. The results indicate that the parabolic solar dish concentrator with sphere receiver has rather high solar energy to net heat efficiency which is 20% more than solar trough and tower system including higher cosine factor and lower heat loss of the receiver.

Huang, Weidong; Hu, Peng; Chen, Zeshao

2011-01-01T23:59:59.000Z

425

High concentration two-stage optics for parabolic trough solar collectors with tubular absorber and large rim angle  

SciTech Connect

A new two-stage optical design is proposed for parabolic trough solar collectors with tubular absorbers. It can boost the concentration ratio by a factor of 2.5 relative to the conventional design, while maintaining the large rim angles (i.e., low nominal f-numbers) that are desirable for practical and economical reasons. The second state involves asymmetric nonimaging concentrators of the CPC type, facing segments of the parabolic first stage. The second stage can be accommodated inside an evacuated receiver, allowing the use of first-surface silvered reflectors. The low heat loss of this design opens the possibility of producing steam at temperatures and pressures of conventional power plants, using only one-axis tracking. The improvement in conversion efficiency would be substantial.

Collares-Pereira, M. (Centro para a Conservacao de Energia, Amadora (Portugal)); Gordon, J.M. (Ben Gurion Univ. of the Negev, Beersheva (Israel)); Rabl, A. (Centre d'Energetique, Paris (France)); Winston, R. (Univ. of Chicago, IL (United States))

1991-01-01T23:59:59.000Z

426

Alternative Fuels Data Center: Energy Task Force  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Energy Task Force to Energy Task Force to someone by E-mail Share Alternative Fuels Data Center: Energy Task Force on Facebook Tweet about Alternative Fuels Data Center: Energy Task Force on Twitter Bookmark Alternative Fuels Data Center: Energy Task Force on Google Bookmark Alternative Fuels Data Center: Energy Task Force on Delicious Rank Alternative Fuels Data Center: Energy Task Force on Digg Find More places to share Alternative Fuels Data Center: Energy Task Force on AddThis.com... More in this section... Federal State Advanced Search All Laws & Incentives Sorted by Type Energy Task Force The Governor's Task Force on Energy Policy is developing a state energy plan to facilitate energy efficiency and the use of alternative and renewable fuels in Tennessee. The energy plan will include a summary of

427

L{sup p} Theory for Super-Parabolic Backward Stochastic Partial Differential Equations in the Whole Space  

SciTech Connect

This paper is concerned with semi-linear backward stochastic partial differential equations (BSPDEs for short) of super-parabolic type. An L{sup p}-theory is given for the Cauchy problem of BSPDEs, separately for the case of p Element-Of (1,2] and for the case of p Element-Of (2,{infinity}). A comparison theorem is also addressed.

Du Kai, E-mail: kdu@fudan.edu.cn; Qiu, Jinniao, E-mail: 071018032@fudan.edu.cn; Tang Shanjian, E-mail: sjtang@fudan.edu.cn [Fudan University, Department of Finance and Control Sciences, School of Mathematical Sciences, and Laboratory of Mathematics for Nonlinear Sciences (China)

2012-04-15T23:59:59.000Z

428

Light Organizing/Organizing Light [Light in Place  

E-Print Network (OSTI)

a street through alter­ nating areas of dark and light, welandscapes, streets and squares. Light summons our spiritfor changing light, both outside rooms (such as streets and

Schwartz, Martin

1992-01-01T23:59:59.000Z

429

Development of Performance Acceptance Test Guidelines for Large Commercial Parabolic Trough Solar Fields: Preprint  

DOE Green Energy (OSTI)

Prior to commercial operation, large solar systems in utility-size power plants need to pass a performance acceptance test conducted by the EPC contractor or owners. In lieu of the present absence of engineering code developed for this purpose, NREL has undertaken the development of interim guidelines to provide recommendations for test procedures that can yield results of a high level of accuracy consistent with good engineering knowledge and practice. The fundamental differences between acceptance of a solar power plant and a conventional fossil-fired plant are the transient nature of the energy source and the necessity to utilize an analytical performance model in the acceptance process. These factors bring into play the need to establish methods to measure steady state performance, potential impacts of transient processes, comparison to performance model results, and the possible requirement to test, or model, multi-day performance within the scope of the acceptance test procedure. The power block and BOP are not within the boundaries of this guideline. The current guideline is restricted to the solar thermal performance of parabolic trough systems and has been critiqued by a broad range of stakeholders in CSP development and technology.

Kearney, D.; Mehos, M.

2010-12-01T23:59:59.000Z

430

Numerical study on coupled fluid flow and heat transfer process in parabolic trough solar collector tube  

SciTech Connect

A unified two-dimensional numerical model was developed for the coupled heat transfer process in parabolic solar collector tube, which includes nature convection, forced convection, heat conduction and fluid-solid conjugate problem. The effects of Rayleigh number (Ra), tube diameter ratio and thermal conductivity of the tube wall on the heat transfer and fluid flow performance were numerically analyzed. The distributions of flow field, temperature field, local Nu and local temperature gradient were examined. The results show that when Ra is larger than 10{sup 5}, the effects of nature convection must be taken into account. With the increase of tube diameter ratio, the Nusselt number in inner tube (Nu{sub 1}) increases and the Nusselt number in annuli space (Nu{sub 2}) decreases. With the increase of tube wall thermal conductivity, Nu{sub 1} decreases and Nu{sub 2} increases. When thermal conductivity is larger than 200 W/(m K), it would have little effects on Nu and average temperatures. Due to the effect of the nature convection, along the circumferential direction (from top to down), the temperature in the cross-section decreases and the temperature gradient on inner tube surface increases at first. Then, the temperature and temperature gradients would present a converse variation at {theta} near {pi}. The local Nu on inner tube outer surface increases along circumferential direction until it reaches a maximum value then it decreases again. (author)

Tao, Y.B.; He, Y.L. [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)

2010-10-15T23:59:59.000Z

431

Side-by-side comparisons of evacuated compound parabolic concentrator and flat plate solar collector systems  

SciTech Connect

Three liquid-based solar heating systems employing different types of solar collectors were tested side by side near Chicago, Illinois for one year. The three different types of collectors were: a flat plate collector with a black-chrome coated absorber plate and one low-iron glass cover; an evacuated-tube compound parabolic concentrator (CPC) with a concentration ratio of 1.1, oriented with tubes and troughs along a north-south axis; and an evacuated-tube CPC collector with a concentration ratio of 1.3 and one low-iron glass cover, with tubes and troughs oriented along an east-west axis. Results indicate that the flat plate collector system was the most efficient during warm weather, but the CPC systems were more efficient during cold weather, but the CPC systems were more efficient during cold weather, and the CPC systems operated under conditions too adverse for the flat plate collector. The computer simulation model ANSIM was validated by means of the side-by-side tests. The model uses analytical solutions to the storage energy balance. ANSIM is compared with the general simulation TRNSYS. (LEW)

McGarity, A.E.; Allen, J.W.; Schertz, W.W.

1983-10-01T23:59:59.000Z

432

An off-axis Cassegrain optimal design for short focal length parabolic solar concentrators  

SciTech Connect

The present work addresses an off-axis Cassegrain optical concentration system. The specific primary collector analyzed, a short focal length parabolic concentrator, is at the University of Florida`s Energy Park. A secondary hyperbolic reflective element was designed to redirect the solar radiation from the primary focal plane to an off-axis target on the polar axis of the primary concentrator. This ground level target will be required for planned experimental work. The analysis was performed using a numerical ray tracing procedure that incorporates both random and systematic errors due to slope and surface irregularities. The optimization process varied secondary element size, curvature, and offset angle, and yielded information required for optimum design. As a single secondary element was found impractical, three elements were designed for use at various time of the year. The numerical analysis predicts that typically 70 to 75 percent of the solar flux incident on the primary concentrator aperture was focused within a 0.5-meter radius. During the design, it was found that this type of compact concentration system is a practical alternative. The optical system is also shown to have advantages that are generally applicable for problems involving short focal length primary concentrators, or when the solar apparatus is to be placed outside the primary collector aperture.

Roman, R.J.; Peterson, J.E.; Goswami, D.Y. [Univ. of Florida, Gainesville, FL (United States). Dept. of Mechanical Engineering

1995-02-01T23:59:59.000Z

433

Secondary and compound concentrators for parabolic-dish solar-thermal power systems  

SciTech Connect

A secondary optical element may be added to a parabolic dish solar concentrator to increase the geometric concentration ratio attainable at a given intercept factor. This secondary may be a Fresnel lens or a mirror, such as a compound elliptic concentrator or a hyperbolic trumpet. At a fixed intercept factor, higher overall geometric concentration may be obtainable with a long focal length primary and a suitable secondary matched to it. Use of a secondary to increase the geometric concentration ratio is more likely to be worthwhile if the receiver temperature is high and if errors in the primary are large. Folding the optical path with a secondary may reduce cost by locating the receiver and power conversion equipment closer to the ground and by eliminating the heavy structure needed to support this equipment at the primary focus. Promising folded-path configurations include the Ritchey-Chretien and perhaps some three-element geometries. Folding the optical path may be most useful in systems that provide process heat.

Jaffe, L.D.; Poon, P.T.

1981-04-15T23:59:59.000Z

434

Charcoal-methanol adsorption refrigerator powered by a compound parabolic concentrating solar collector  

SciTech Connect

A compound parabolic concentrating solar collector (CPC) of concentration ratio 3.9 and aperture area 2.0 m[sup 2] was used to power an intermittent solid adsorption refrigerator and ice maker using activated charcoal (carbon) as the adsorbing medium and methanol as the working fluid. The copper tube receiver of the CPC was packed with 2.5 kg of imported adsorbent 207E3, which was only utilized when the performance of activated charcoal (ACJ1, produced from local coconut shells) was found to be inferior to the imported adsorbent. Up to 1 kg of ice at an evaporator temperature of [minus]6[degrees]C was produced, with the net solar coefficient of performance (COP) being of the order of 0.02. Maximum receiver/adsorbent temperature recorded was 154[degrees]C on a day when the insolation was 26.8 MJ/m[sup [minus]2]. Temperatures in excess of 150[degrees]C are undesirable since they favour the conversion of methanol to dimethyl ether, a noncondensable gas which inhibits both condensation and adsorption. The major advantage of this system is its ability to produce ice even on overcast days (insolation [approximately] 10 MJ/m[sup [minus]2]).

Headley, O.StC.; Kothdiwala, A.F.; McDoom, I.A. (Univ. of the West Indies, St. Augustine (Trinidad and Tobago))

1994-08-01T23:59:59.000Z

435

FAQS Job Task Analyses - Nuclear Safety Specialist  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

JOB / TASK ANALYSIS for JOB / TASK ANALYSIS for Nuclear Safety Specialist (NSS) Functional Area Qualification Standard (FAQS) DOE-STD-1183-2007 Instructions for Step 1: Step 1 Identify and evaluate tasks - Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered. o Don't worry about deleting tasks at this point - that is a part of the process further down. - List the tasks (and their sources, e.g., Duties and Responsibilities #1) in the chart below. - Discuss each task as a group and come to a consensus pertaining to Importance and Frequency of the task (i.e., each team member can consent to the assigned value, even

436

Solid-State Lighting: LED Lighting Facts  

NLE Websites -- All DOE Office Websites (Extended Search)

Market-Based Programs Printable Version Share this resource Send a link to Solid-State Lighting: LED Lighting Facts to someone by E-mail Share Solid-State Lighting: LED Lighting Facts on Facebook Tweet about Solid-State Lighting: LED Lighting Facts on Twitter Bookmark Solid-State Lighting: LED Lighting Facts on Google Bookmark Solid-State Lighting: LED Lighting Facts on Delicious Rank Solid-State Lighting: LED Lighting Facts on Digg Find More places to share Solid-State Lighting: LED Lighting Facts on AddThis.com... LED Lighting Facts CALiPER Program Standards Development Technical Information Network Gateway Demonstrations Municipal Consortium Design Competitions LED Lighting Facts LED lighting facts - A Program of the U.S. DOE DOE's LED Lighting Facts® program showcases LED products for general

437

Industrial Lighting Techniques and New Developments  

E-Print Network (OSTI)

The energy crisis of the early seventies has had a drastic influence on both the application and development of light sources. This situation has forced us to examine old methods and search for new answers for improved efficiency. We can no longer operate on the premise that more is better. At lower light levels a lighting design is less forgiving. The current thrust in lamp and luminare design has been high efficiency. Tremendous effort has been expended to produce energy efficient sources that deliver better color, improved optical control, and reduced lamp size. Given that we must operate in this arena of heightened energy awareness and that lighting, by its very nature, becomes a prime candidate for reduction, we must not lose sight of the fundamental reason for lighting to provide the ability for us to see details to perform specific tasks. The heart of an industrial plant is the production area. A myriad of tasks must be accomplished. Lighting is installed for humans, not machines. The eye can only adapt to a degree and accommodate a variety of conditions; i.e., color, texture, etc. Higher light levels are required as an individual’s age increases. It has also been confirmed in many studies that light levels directly affect performance. People who have sufficient quantity and quality of illumination can accomplish their work faster and more accurately. A delicate balance lies between energy efficient lighting and under and over-lit spaces. This balance is with the fundamental lighting goal. Any formula to maintain this balance should include two vital factors: First, light output for levels and quality determined by proper task analysis and second, control by design which utilizes the best source and equipment available.

Colotti, M. A.

1985-05-01T23:59:59.000Z

438

Luminance in computer-aided lighting design  

SciTech Connect

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually ``sees``. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its importance to lighting design, luminance is rarely used because there is a lack of the necessary computational tools.In this paper, we will demonstrate a computer calculation of luminance that has significant advantages for lighting design. As well as providing an immediate evaluation of visual quality for task performance, less quantifiable factors such as aesthetics can be studied in synthetic images produced by the program.

Ward, G.J.; Rubinstein, F.M.; Grynberg, A.

1987-08-01T23:59:59.000Z

439

Luminance in computer-aided lighting design  

SciTech Connect

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually sees''. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its importance to lighting design, luminance is rarely used because there is a lack of the necessary computational tools.In this paper, we will demonstrate a computer calculation of luminance that has significant advantages for lighting design. As well as providing an immediate evaluation of visual quality for task performance, less quantifiable factors such as aesthetics can be studied in synthetic images produced by the program.

Ward, G.J.; Rubinstein, F.M.; Grynberg, A.

1987-08-01T23:59:59.000Z

440

FAQS Job Task Analyses - Environmental Compliance FAQS  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Environmental Compliance Functional Area Qualification Standard Environmental Compliance Functional Area Qualification Standard DOE-STD-1156-2011 Step 1 Identify and evaluate tasks - Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered. o Don't worry about deleting tasks at this point - that is a part of the process further down. - List the tasks (and their sources, e.g., Duties and Responsibilities #1) in the chart below. - Discuss each task as a group and come to a consensus pertaining to Importance and Frequency of the task (i.e., each team member can consent to the assigned value, even if they don't exactly agree with it). - When all values have been assigned, consider as a group deleting tasks

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


441

FAQS Job Task Analyses - Construction Management  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

80-2004: Construction Management Functional Area Qualification Standard 80-2004: Construction Management Functional Area Qualification Standard 1 Conducting the Job / Task Analysis DOE-STD-1180-2004: Construction Management Functional Area Qualification Standard Step 1: Identify and evaluate tasks * Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered. o Don't worry about deleting tasks at this point - that is a part of the process further down. * List the tasks (and their sources, e.g., Duties and Responsibilities #1) in the chart below. * Discuss each task as a group and come to a consensus pertaining to Importance and Frequency of the task (i.e., each team

442

FAQS Job Task Analyses - Safeguards and Security  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE-STD-1171 DOE-STD-1171 Safeguards and Security FAQ Step 1 Identify and evaluate tasks - Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered. o Don't worry about deleting tasks at this point - that is a part of the process further down. - List the tasks (and their sources, e.g., Duties and Responsibilities #1) in the chart below. - Discuss each task as a group and come to a consensus pertaining to Importance and Frequency of the task (i.e., each team member can consent to the assigned value, even if they don't exactly agree with it). - When all values have been assigned, consider as a group deleting tasks that receive

443

Nuclear Radiological Threat Task Force Established | National...  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiological Threat Task Force Established | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy...

444

An overview of task order 10  

DOE Green Energy (OSTI)

Task Order 10 formalizes a collaboration in high explosive pulsed power (HEPP) experiments between LANL and VNIIEF. The focus is the VNIIEF disk explosive magnetic generator (DEMG) technology. The task order outlines a sequence of tasks and deliverables culminating in an experiment which takes place in the US utilizing US explosives and a Russian DEMG. This talk summarizes task order 10. It gives a brief history and present status in terms of the proposed high pressure EOS experiment (ALT-3).

Rousculp, Christopher L [Los Alamos National Laboratory

2011-01-12T23:59:59.000Z

445

NREL Job Task Analysis: Crew Leader  

Science Conference Proceedings (OSTI)

A summary of job task analyses for the position of crew leader when conducting weatherization work on a residence.

Kurnik, C.; Woodley, C.

2011-05-01T23:59:59.000Z

446

Turbo-Charged Lighting Design  

E-Print Network (OSTI)

The task of the lighting designer has become very complex, involving thousands of choices for fixture types and hundreds of possible lamps. The designer who can consider the most combinations of these items guarantees each client the optimal lighting conditions and the best energy efficiency. This kind of professional service, however, is not available from the software design programs presently on the market. These programs generally let the designer analyze one room at a time, while providing perhaps three possible fixtures to choose from. Additional choices can be accessed from the software’s data base, though at considerable expense in time and patience. This is a real hindrance when designing for a complex structure such as a hospital, which has many spaces with different task-specific lighting standards. The author was challenged by lighting-level requirements that spanned the range of possibilities, and was able to devise an accurate, expedient solution using a dBase language program. The result was a powerful tool integrating the entire gamut of design possibilities provided by the luminaire industry.

Clark, W. H. II

1992-05-01T23:59:59.000Z

447

A novel algorithm for dynamic task scheduling  

Science Conference Proceedings (OSTI)

This paper deals with the problem of dynamic task scheduling in grid environment of multi-processors. First, this paper formulates task scheduling as an optimization problem and then optimizes with a novel hybrid optimization algorithm. The proposed ... Keywords: Bacteria foraging optimization, Genetic algorithms, Grid computing, Task scheduling

Sasmita Kumari Nayak; Sasmita Kumari Padhy; Siba Prasada Panigrahi

2012-05-01T23:59:59.000Z

448

Middleware support for many-task computing  

Science Conference Proceedings (OSTI)

Many-task computing aims to bridge the gap between two computing paradigms, high throughput computing and high performance computing. Many-task computing denotes high-performance computations comprising multiple distinct activities, coupled via file ... Keywords: Computing, Data-intensive distributed computing, Falkon, High-performance computing, High-throughput, Loosely-coupled applications, Many-task computing, Petascale, Swift

Ioan Raicu; Ian Foster; Mike Wilde; Zhao Zhang; Kamil Iskra; Peter Beckman; Yong Zhao; Alex Szalay; Alok Choudhary; Philip Little; Christopher Moretti; Amitabh Chaudhary; Douglas Thain

2010-09-01T23:59:59.000Z

449

Light Computing  

E-Print Network (OSTI)

A configuration of light pulses is generated, together with emitters and receptors, that allows computing. The computing is extraordinarily high in number of flops per second, exceeding the capability of a quantum computer for a given size and coherence region. The emitters and receptors are based on the quantum diode, which can emit and detect individual photons with high accuracy.

Gordon Chalmers

2006-10-13T23:59:59.000Z

450

Detroit Public Lighting Department - Residential Energy Wise Program |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Detroit Public Lighting Department - Residential Energy Wise Detroit Public Lighting Department - Residential Energy Wise Program Detroit Public Lighting Department - Residential Energy Wise Program < Back Eligibility Low-Income Residential Multi-Family Residential Residential Savings Category Heating & Cooling Cooling Appliances & Electronics Commercial Lighting Lighting Program Info State Michigan Program Type Utility Rebate Program Rebate Amount CFLs: $2-$10 LED Task Light: $10.00 LED Night light: $1.25 Energy Star Ceiling Fan: $10 Provider Detroit Public Lighting Department The Detroit Public Lighting Department (PLD) offers residential customers rebates for energy efficient lights. In addition, low-income residential customers may qualify for free compact fluorescent lights (CFLs). Specific rebate amounts, equipment requirements, and applications are available on

451

EK101 Engineering Light Smart Lighting  

E-Print Network (OSTI)

extensively in concert lighting and are finding increased usage in dance lighting because refers to the upstage back curtain (is white or a light color), which can be us for lighting or special Mixer #12;Monitor House speaker Lighting System Control Board: Similar to the sound board, the light

Bifano, Thomas

452

NEXT\tCALL 2013\tProposal\tCall\t#1 TASK\tPLAN TASK\tPLAN TASK\tENDS...  

NLE Websites -- All DOE Office Websites (Extended Search)

NEXT CALL 2013 Proposal Call 1 TASK PLAN TASK PLAN TASK ENDS CYCLE TIME CYCLE TIME CYCLE TIME CYCLE TIME ACTUAL CURRENT SUBMISSIONS TASKS (START DATE) (END DATE) (ACTUAL DATE)...

453

Development of Molten-Salt Heat Transfer Fluid Technology for Parabolic Trough Solar Power Plants - Public Final Technical Report  

SciTech Connect

Executive Summary This Final Report for the "Development of Molten-Salt Heat Transfer Fluid (HTF) Technology for Parabolic Trough Solar Power Plants” describes the overall project accomplishments, results and conclusions. Phase 1 analyzed the feasibility, cost and performance of a parabolic trough solar power plant with a molten salt heat transfer fluid (HTF); researched and/or developed feasible component options, detailed cost estimates and workable operating procedures; and developed hourly performance models. As a result, a molten salt plant with 6 hours of storage was shown to reduce Thermal Energy Storage (TES) cost by 43.2%, solar field cost by 14.8%, and levelized cost of energy (LCOE) by 9.8% - 14.5% relative to a similar state-of-the-art baseline plant. The LCOE savings range met the project’s Go/No Go criteria of 10% LCOE reduction. Another primary focus of Phase 1 and 2 was risk mitigation. The large risk areas associated with a molten salt parabolic trough plant were addressed in both Phases, such as; HTF freeze prevention and recovery, collector components and piping connections, and complex component interactions. Phase 2 analyzed in more detail the technical and economic feasibility of a 140 MWe,gross molten-salt CSP plant with 6 hours of TES. Phase 2 accomplishments included developing technical solutions to the above mentioned risk areas, such as freeze protection/recovery, corrosion effects of applicable molten salts, collector design improvements for molten salt, and developing plant operating strategies for maximized plant performance and freeze risk mitigation. Phase 2 accomplishments also included developing and thoroughly analyzing a molten salt, Parabolic Trough power plant performance model, in order to achieve the project cost and performance targets. The plant performance model and an extensive basic Engineering, Procurement, and Construction (EPC) quote were used to calculate a real levelized cost of energy (LCOE) of 11.50˘/kWhe , which achieved the Phase 2 Go/No Go target of less than 0.12˘/kWhe. Abengoa Solar has high confidence that the primary risk areas have been addressed in the project and a commercial plant utilizing molten salt is economically and technically feasible. The strong results from the Phase 1 and 2 research, testing, and analyses, summarized in this report, led Abengoa Solar to recommend that the project proceed to Phase 3. However, a commercially viable collector interconnection was not fully validated by the end of Phase 2, combined with the uncertainty in the federal budget, forced the DOE and Abengoa Solar to close the project. Thus the resources required to construct and operate a molten salt pilot plant will be solely supplied by Abengoa Solar.

Grogan, Dylan C. P.

2013-08-15T23:59:59.000Z

454

FAQS Job Task Analyses - Deactivation and Decommissioning  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Functional Area Qualification Standard Functional Area Qualification Standard Deactivation & Decommissioning (D&D) DOE-STD-1166-2003 Step 1 Identify and evaluate tasks - Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered. o Don't worry about deleting tasks at this point - that is a part of the process further down. - List the tasks (and their sources, e.g., Duties and Responsibilities #1) in the chart below. - Discuss each task as a group and come to a consensus pertaining to Importance and Frequency of the task (i.e., each team member can consent to the assigned value, even if they don't exactly agree with it).

455

Army Energy Initiatives Task Force  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

UNCLASSIFIED UNCLASSIFIED Army Energy Initiatives Task Force Kathy Ahsing Director, Planning and Development UNCLASSIFIED 2 Perfect Storm UNCLASSIFIED 3 U.S. Army Energy Consumption, 2010 23% 77% 42% 58%  Facilities  Vehicles & Equipment (Tactical and Non-tactical) Sources: Energy Information Agency, 2010 Annual Energy Review; Agency Annual Energy Management Data Reports submitted to DOE's Federal Energy Management Program (Preliminary FY 2010) 32% 68% DoD 80% Army 21% Federal Gov 1% Federal Government United States Department of Defense U.S. = 98,079 Trillion Btu DoD = 889 Trillion Btu Fed Gov = 1,108 Trillion Btu U.S. Army = 189 Trillion Btu FY10 Highlights - $2.5+B Operational Energy Costs - $1.2 B Facility Energy Costs

456

Light Emitting Diode (LED) Lighting and Systems  

Science Conference Proceedings (OSTI)

This EPRI Technical Update addresses the most promising and unique energy efficient light source light emitting diode (LED) lighting. Business and technical market factors (Chapter 2) explain the upcoming growth of the LED and LED lighting market. Future technical improvements to LEDs and systems are also emphasized. Discussion of the importance of utility involvement in helping their customers make the switch from traditional lighting to LED lighting is provided. LED lighting technologies are covered in...

2007-12-21T23:59:59.000Z

457

Integrated lighting approach saves energy in post office facilities  

SciTech Connect

The United States Postal Service (USPS) has made numerous efforts to improve the lighting quality and efficiency in their facilities. These efforts have included both traditional retrofits such as the transition to T8 lamps/electronic ballasts and more experimental approaches such as light pipes and sulfur lamps. However, these efforts have focused primarily on their industrial and plant facilities and have had little impact on their small and medium sized facilities, which comprise roughly 90% of their total building stock. These efforts have also neglected the affinity between task and ambient lighting functions.The objective of this project was to develop and demonstrate an integrated lighting system that saves energy while improving the lighting distribution and quality in small and medium sized USPS facilities. Work included the evolution of a novel task lighting fixture designed explicitly to improve the light distribution within the carrier case letter sorting station. The new t ask light system was developed to work in combination with a high efficiency, low-glare ambient lighting system mounted on the ceiling. The use of high-performance task lighting allowed the ambient lighting component to be reduced, thereby limiting the amount of glare produced and reducing the amount of energy consumed.

Mitchell, Jeffrey C.; Siminovitch, Michael J.; Page, Eric R.; Gauna, Kevin W.; Avery, Douglas A.

2000-06-01T23:59:59.000Z

458

Employee Job Task Analysis (EJTA) PIA, Richland Operations Office...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Job Task Analysis (EJTA) PIA, Richland Operations Office Employee Job Task Analysis (EJTA) PIA, Richland Operations Office Employee Job Task Analysis (EJTA) PIA, Richland...

459

Joint Outreach Task Group Former Workers Screening Program |...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Joint Outreach Task Group Former Workers Screening Program Joint Outreach Task Group Former Workers Screening Program The Joint Outreach Task Group (JOTG) includes representatives...

460

Smart Grid Task Force Presentations | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Services Technology Development Smart Grid Federal Smart Grid Task Force Smart Grid Task Force Presentations Smart Grid Task Force Presentations Presentations about the...

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


461

Smart Grid Task Force Presentations | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Smart Grid Federal Smart Grid Task Force Smart Grid Task Force Presentations Smart Grid Task Force Presentations Electricity Advisory Committee Technology Development...

462

The heat-balance integral method by a parabolic profile with unspecified exponent: Analysis and Benchmark Exercises  

E-Print Network (OSTI)

The heat-balance integral method of Goodman has been thoroughly analyzed in the case of a parabolic profile with unspecified exponent depending on the boundary condition imposed. That the classical Good man's boundary conditions defining the time-dependent coefficients of the prescribed temperature profile do not work efficiently at the front of the thermal layers if the specific parabolic profile at issue is employed. Additional constraints based on physical assumption enhance the heat-balance integral method and form a robust algorithm defining the parabola exponent . The method has been compared by results provided by the Veinik's method that is by far different from the Good man's idea but also assume forma tion of thermal layer penetrating the heat body. The method has been demonstrated through detailed solutions of 4 1-D heat-conduction problems in Cartesian co-ordinates including a spherical problem (through change of vari ables) and over-specified boundary condition at the face of the thermal layer.

Jordan Hristov

2010-12-12T23:59:59.000Z

463

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish: I-test and analysis  

DOE Green Energy (OSTI)

The concept of solar driven chemical reaction in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH[sub 4]) with carbon dioxide (CO[sub 2]) was achieved in a 64 cm diameter direct absorption reactor on a parabolic dish capable of 150 kW solar power. The reactor was a catalytic volumetric absorber consisting of a multilayered, porous alumina foam disk coated with rhodium (Rh) catalyst. The system was operated during both steady-state and solar transient (cloud passage) conditions. The total solar power absorbed reached values up to 97 kW and the maximum methane conversion was 70%. Receiver thermal efficiencies ranged up to 85% and chemical efficiencies peaked at 54%. The absorber performed satisfactorily in promoting the reforming reaction during the tests without carbon formation. However, problems of cracking and degradation of the porous matrix, nonuniform dispersion of the Rh through the absorber, the catalyst deactivation due to sintering and possible encapsulation, must be resolved to achieve long-term operation and eventual commercialization.

Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. (Sandia National Lab., Albuquerque, NM (United States)); Buck, R. (DLR-ITT, Stuttgart (Germany))

1994-06-01T23:59:59.000Z

464

Phase 0: goal study for the technical and economic evaluation of the Compound Parabolic Concentrator (CPC) concept applied to solar thermal and photovoltaic collectors. Final report  

DOE Green Energy (OSTI)

This report presents the results of a quick, six-week technical and economic evaluation of the compound parabolic concentrator (CPC) solar collector. The purpose of this effort was to provide an initial phase of a goals study that is directed toward recommending relative priorities for development of the compound parabolic concentrator concept. The findings of this study are of a very preliminary nature. Conclusions based on study findings at this depth should be considered preliminary and subject to revision and review in later phases.

None

1975-06-01T23:59:59.000Z

465

FAQS Job Task Analyses - Facility Representative  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Job/Task Analysis Job/Task Analysis Importance Scale Frequency Scale Competency Need Timeframe 0 Not Performed or N/A 3 Important 0 Not Performed 3 Every few days to weekly 1 On first day 4 After 1st 6 months 1 Not Important 4 Very Important 1 Every few months to yearly 4 Every few hours to daily 2 Within first 3 months 5 Prior to Qualification 2 Somewhat Important 5 Extremely Important 2 Every few weeks to monthly 5 Hourly to many times each hour 3 Within first 4-6 months 1 CONDUCTING THE JOB / TASK ANALYSIS Step 1 Identify and evaluate tasks - Develop a comprehensive list of tasks that define the job. o A great starting point is the list of Duties and Responsibilities from the FAQS. o Give careful thought to additional tasks that could be considered.

466

Energy and economic efficiency alternatives for electric lighting in commercial buildings  

SciTech Connect

This report investigates current efficient alternatives for replacing or supplementing electric lighting systems in commercial buildings. Criteria for establishing the economic attractiveness of various lighting alternatives are defined and the effect of future changes in building lighting on utility capacity. The report focuses on the energy savings potential, economic efficiency, and energy demand reduction of three categories of lighting alternatives: (1) use of a renewable resource (daylighting) to replace or supplement electric lighting; (2) use of task/ambient lighting in lieu of overhead task lighting; and (3) equipment changes to improve lighting energy efficiency. The results indicate that all three categories offer opportunities to reduce lighting energy use in commercial buildings. Further, reducing lighting energy causes a reduction in cooling energy use and cooling capacity while increasing heating energy use. It does not typically increase heating capacity because the use of lighting in the building does not offset the need for peak heating at night.

Robbins, C.L.; Hunter K.C.; Carlisle, N.

1985-10-01T23:59:59.000Z

467

Energy and lighting design  

SciTech Connect

A detailed examination of the current energy conservation practices for lighting systems is presented. This first part of a two-part presentation covers the following: energy and lighting design; lighting and energy standards; lighting efficiency factors; light control and photometrics; lighting and the architectural interior; luminaire impact on the environment; basic design techniques; the lighting power budget; and conservation through control.

Helms, R.N.

1979-11-01T23:59:59.000Z

468

ACE R&D Task Definition Plans  

Science Conference Proceedings (OSTI)

ACE R&D Task Definition Plans. EDT+. Redefine/Add entity types; Add tracking across documents; Add (and normalize) attributes. ...

469

NREL Job Task Analysis: Quality Control Inspector  

SciTech Connect

A summary of job task analyses for the position of quality control inspector when evaluating weatherization work that has been done on a residence.

Kurnik, C.; Woodley, C.

2011-05-01T23:59:59.000Z

470

NREL Job Task Analysis: Energy Auditor  

SciTech Connect

A summary of job task analyses for the position of energy auditor when evaluating a residence before and during weatherization work.

Kurnik, C.; Woodley, C.

2011-05-01T23:59:59.000Z

471

Internet Engineering Task Force KK Ramakrishnan ...  

Science Conference Proceedings (OSTI)

... Engineering Task Force KK Ramakrishnan INTERNET DRAFT AT&T Labs Research draft-kksjf-ecn-00.txt Sally Floyd LBNL November 1997 ...

2009-08-19T23:59:59.000Z

472

Joint Outreach Task Group Calendar: September 2013  

Energy.gov (U.S. Department of Energy (DOE))

Joint Outreach Task Group (JOTG)has created a monthly calendar of community events to facilitate interagency and community involvement in these events. September 2013

473

AGSD Task 3.5 Test Plan  

NLE Websites -- All DOE Office Websites (Extended Search)

CMC Bench Scale Material Test Plan TOPICAL REPORT Reporting Period Start Date: February 1, 2006 End Date: May 30, 2006 Principal Authors Mark Fitzsimmons Task Development Lead...

474

TREC 2007 Legal Track: Main Task Glossary  

Science Conference Proceedings (OSTI)

TREC 2007 Legal Track: Main Task Glossary. Revision History. 2007 Oct 2: st: first draft. qrelsL07.normal. The qrelsL07.normal ...

475

Weardale Task Force | Open Energy Information  

Open Energy Info (EERE)

search Name Weardale Task Force Place England, United Kingdom Sector Biomass, Geothermal energy, Hydro, Solar, Wind energy Product Durham based project consortium that is...

476

Light Emitting Diodes and General Lighting  

NLE Websites -- All DOE Office Websites (Extended Search)

Light Emitting Diodes and General Lighting Speaker(s): Martin Moeck Date: August 6, 2009 - 12:00pm Location: 90-3122 We give a short overview on high-power light emitting diodes,...

477

Evaluation of Lighting and Lighting Control Technologies  

Science Conference Proceedings (OSTI)

Energy efficient lighting and lighting controls have been a means to significant energy savings for many facilities around the world. Advances in lighting sources often allow for the conservation of quality of light while providing more flexibility in the control of light. Additionally, advances in core technologies within the lighting marketplace regularly lead to the introduction of new lamps, fixtures and controls.  With the rapid introduction of new products and designs, it is important to ...

2013-11-15T23:59:59.000Z

478

Lighting Group: Controls: PIER Lighting Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

PIER Lighting Projects CEC Public Interest Energy Research (PIER) Projects Objective Lighting controls are often expensive, complex, hard to commission properly and difficult to...

479

Architectural Lighting Analysis in Virtual Lighting Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Architectural Lighting Analysis in Virtual Lighting Laboratory NOTICE Due to the current lapse of federal funding, Berkeley Lab websites are accessible, but may not be updated...

480

Which LED Lighting Products Would You Consider Trying? | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Which LED Lighting Products Would You Consider Trying? Which LED Lighting Products Would You Consider Trying? Which LED Lighting Products Would You Consider Trying? August 5, 2010 - 7:30am Addthis On Monday, Chris discussed his upcoming project to replace the lighting in his kitchen and family room. Chris is considering LED (light-emitting diode) lighting, especially for his kitchen, where they can be installed under the cabinets. LEDs can also be used for other applications, including task lighting, recessed downlights, and holiday lighting. Which LED lighting products would you consider trying? Or, if you're already using LEDs, what do you think of them? Each Thursday, you have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. Please comment with your answers, and also feel free to respond to other comments.

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


481

Spectrally Enhanced Lighting Program Implementation for Energy Savings: Field Evaluation  

Science Conference Proceedings (OSTI)

This report provides results from an evaluation PNNL conducted of a spectrally enhanced lighting demonstration project. PNNL performed field measurements and occupant surveys at three office buildings in California before and after lighting retrofits were made in August and December 2005. PNNL measured the following Overhead lighting electricity demand and consumption, Light levels in the workspace, Task lighting use, and Occupant ratings of satisfaction with the lighting. Existing lighting, which varied in each building, was replaced with lamps with correlated color temperature (CCT) of 5000 Kelvin, color rendering index (CRI) of 85, of varying wattages, and lower ballast factor electronic ballasts. The demonstrations were designed to decrease lighting power loads in the three buildings by 22-50 percent, depending on the existing installed lamps and ballasts. The project designers hypothesized that this reduction in electrical loads could be achieved by the change to higher CCT lamps without decreasing occupant satisfaction with the lighting.

Gordon, Kelly L.; Sullivan, Gregory P.; Armstrong, Peter R.; Richman, Eric E.; Matzke, Brett D.

2006-08-22T23:59:59.000Z

482

FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force Meeting Agenda  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force Meeting Agenda FEDERAL SMART GRID TASK FORCE - February 26, 2009 Task Force Meeting Agenda February 26, 2009 Task Force Meeting Agenda - CONFERENCE CALL Agenda FEDERAL SMART GRID TASK FORCE CONFERENCE CALL February 26, 2009 10:00-11:00 AM 10:00 Opening and Introduction - Eric Lightner, DOE * Call the meeting to order, around-the-table introductions, review of the agenda, additions to agenda 10:05 Update from DOE - Eric Lightner * Stimulus update * E-Forum * Fact sheet - discussion 10:30 Update from FERC - Ray Palmer, David Andrejcak * NARUC-FERC Smart Grid Collaborative meeting update 10:40 Update from NIST - William Anderson, Jerry FitzPatrick * Interoperability Standards Framework report to Congress

483

Modeling the mental differentiation task with EEG  

Science Conference Proceedings (OSTI)

Differentiation in human beings is the act of perceiving the difference in or between objects. In other words, it is the mental process taking place to discriminate one thing from others, a common task performed by a person on a very regular basis. Making ... Keywords: BCI, EEG, artifical neural network, biosignal processing, differencitation tasks

Tan Vo; Tom Gedeon; Dat Tran

2012-11-01T23:59:59.000Z

484

Probability of passing through a parabolic barrier and thermal decay rate: Case of linear coupling both in momentum and in coordinate  

SciTech Connect

With the quantum diffusion approach, the probability of passing through the parabolic barrier and the quasistationary thermal decay rate from a metastable state are examined in the limit of linear coupling both in momentum and in coordinate between a collective subsystem and the environment. An increase of passing probability with friction coefficient is demonstrated to occur at subbarrier energies.

Kuzyakin, R. A. [Joint Institute for Nuclear Research, RU-141980 Dubna (Russian Federation); Omsk State Transport University, RU-644046 Omsk (Russian Federation); Sargsyan, V. V. [Joint Institute for Nuclear Research, RU-141980 Dubna (Russian Federation); Yerevan State University, International Center for Advanced Studies, Yerevan (Armenia); Adamian, G. G.; Antonenko, N. V. [Joint Institute for Nuclear Research, RU-141980 Dubna (Russian Federation)

2011-09-15T23:59:59.000Z

485

FAQS Job Task Analyses - Fire Protection Engineering  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Job Task Analysis and Competency Review Job Task Analysis and Competency Review for All Level Competencies Fire Protection Engineering FAQS Initially conducted (expert competencies): August 2010 Updated (includes ALL Competencies): April 2011 Updated (includes ALL Competencies): October 2012 STEP 1: Job Task Analysis for Tasks Task (and Number) Source Importance Frequency Serve as the subject matter expert in the area of fire protection, life safety, and fire department emergency related services. FAQS Duties and Responsibilities Paragraph A 5 4 Review fire hazard analyses, assessments, and other fire safety documentation for compliance with applicable requirements. FAQS Duties and Responsibilities Paragraph B 5 3 Evaluate the adequacy of site emergency services. This includes all facets of the fire

486

FAQS Job Task Analyses - Technical Training  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Technical Training FAQS Technical Training FAQS August 2010 STEP 1: Job Task Analysis for Tasks Task (and Number) Source Importance Frequency (1) Collaborate with the DOE-wide training community to analyze, design, develop, implement, evaluate, and share required courses and programs that have application beyond the local organization. FAQS Duties and Responsibilities Paragraph 6 3 1 (2) Design and develop training curriculum and/or courses using methods suitable for the target audience, including technology- supported learning when appropriate and cost effective. FAQS Duties and Responsibilities Paragraph 7 4 2 (3) Conduct training sessions and formal presentations. FAQS Duties and Responsibilities Paragraph 8 2 2 Importance Scale Frequency How important is this task to the job? How often is the task performed?

487

Next Generation Light Source  

•Next Generation Light Source – Super Thin Light Bulb, Energy Efficient, Long Life, Dimmable, and Uniform Illumination •High Entry Barrier – 71 ...

488

Hysteresis and re-entrant melting of a self-organized system of classical particles confined in a parabolic trap  

E-Print Network (OSTI)

A self-organized system composed of classical particles confined in a two-dimensional parabolic trap and interacting through a potential with a short-range attractive part and long-range repulsive part is studied as function of temperature. The influence of the competition between the short-range attractive part of the inter-particle potential and its long-range repulsive part on the melting temperature is studied. Different behaviors of the melting temperature are found depending on the screening length ($\\kappa$) and the strength ($B$) of the attractive part of the inter-particle potential. A re-entrant behavior and a thermal induced phase transition is observed in a small region of ($\\kappa,B$)-space. A structural hysteresis effect is observed as a function of temperature and physically understood as due to the presence of a potential barrier between different configurations of the system.

F. F. Munarin; K. Nelissen; W. P. Ferreira; G. A. Farias; F. M. Peeters

2007-07-10T23:59:59.000Z

489

A Gas Dynamics Method Based on The Spectral Deferred Corrections (SDC) Time Integration Technique and The Piecewise Parabolic Method (PPM)  

SciTech Connect

We present a computational gas dynamics method based on the Spectral Deferred Corrections (SDC) time integration technique and the Piecewise Parabolic Method (PPM) finite volume method. The PPM framework is used to define edge averaged quantities which are then used to evaluate numerical flux functions. The SDC technique is used to integrate solution in time. This kind of approach was first taken by Anita et al in [17]. However, [17] is problematic when it is implemented to certain shock problems. Here we propose significant improvements to [17]. The method is fourth order (both in space and time) for smooth flows, and provides highly resolved discontinuous solutions. We tested the method by solving variety of problems. Results indicate that the fourth order of accuracy in both space and time has been achieved when the flow is smooth. Results also demonstrate the shock capturing ability of the method.

Samet Y. Kadioglu

2011-12-01T23:59:59.000Z

490

Group velocity dispersion and relativistic effects on the wakefield induced by chirped laser pulse in parabolic plasma channel  

SciTech Connect

The excitation of wake field plasma waves by a short laser pulse propagating through a parabolic plasma channel is studied. The laser pulse is assumed to be initially chirped. In this regard, the effects of initial and induced chirp on the plasma wake field as well as the laser pulse parameters are investigated. The group velocity dispersion and nonlinear relativistic effects were taken into account to evaluate the excited wake field in two dimension using source dependent expansion method. Positive, negative, and un-chirped laser pulses were employed in numerical code to evaluate the effectiveness of the initial chirp on 2-D wake field excitation. Numerical results showed that for laser irradiances exceeding 10{sup 18}W/cm{sup 2}, an intense laser pulse with initial positive chirp generates larger wake field compared to negatively and un-chirped pulses.

Sohbatzadeh, F. [Department of Atomic and Molecular Physics, Science Faculty, University of Mazandaran, Babolsar (Iran, Islamic Republic of); Akou, H. [Department of Physics, Faculty of Basic Science, Babol University of Technology, Babol 47148-71167 (Iran, Islamic Republic of)

2013-04-15T23:59:59.000Z

491

Effect of variation of angle of inclination on the performance of low-concentration-ratio compound parabolic concentrating solar collectors  

SciTech Connect

Thermal heat transfer in line-axis, symmetric, compound parabolic concentrating solar energy collectors (CPCs) has been investigated and a theoretical numerical model has been developed. The model allows the effect of the angle of axial inclination of an east-west aligned CPC and hence the effect of the latitudinal and tracking configuration of the CPC system on performance to be determined. The internal and external convective heat transfer correlations employed are angular dependent. The variation of convective, radiative, conductive and overall heat transfer coefficients and system efficiency for a range of angular inclinations, concentration ratios, total insolations and beam to diffuse insolation factors are presented graphically. The results demonstrate that there is a 10% variation in convective heat transfer with angle of inclination for low concentration CPCs (i.e. C=1.5). 13 refs., 12 figs., 2 tabs.

A.F. Kothdiwala; Norton, B.; Eames, P.C. [Univ. of Ulster, Antrim (United Kingdom)

1995-12-31T23:59:59.000Z

492

First Light  

E-Print Network (OSTI)

The first dwarf galaxies, which constitute the building blocks of the collapsed objects we find today in the Universe, had formed hundreds of millions of years after the big bang. This pedagogical review describes the early growth of their small-amplitude seed fluctuations from the epoch of inflation through dark matter decoupling and matter-radiation equality, to the final collapse and fragmentation of the dark matter on all mass scales above \\~10^{-4} solar masses. The condensation of baryons into halos in the mass range of ~10^5-10^{10} solar masses led to the formation of the first stars and the re-ionization of the cold hydrogen gas, left over from the big bang. The production of heavy elements by the first stars started the metal enrichment process that eventually led to the formation of rocky planets and life. A wide variety of instruments currently under design [including large-aperture infrared telescopes on the ground or in space (JWST), and low-frequency arrays for the detection of redshifted 21cm radiation], will establish better understanding of the first sources of light during an epoch in cosmic history that was largely unexplored so far. Numerical simulations of reionization are computationally challenging, as they require radiative transfer across large cosmological volumes as well as sufficently high resolution to identify the sources of the ionizing radiation. The technological challenges for observations and the computational challenges for numerical simulations, will motivate intense work in this field over the coming decade.

Abraham Loeb

2006-03-14T23:59:59.000Z

493

Solid State Lighting Program  

SciTech Connect

The project had two main tasks: One addressed the materials and device development and it was carried out at Boston University. The second addressed the theory and simulation of materials and devices and it was carried out at Science Application International Corporation (SAIC). Each task had a number of sub-tasks which are described in the following table. Progress in these tasks is described in this section.

Theodore D. Moustakas

2007-11-30T23:59:59.000Z

494

Lighting | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Lighting Lighting Lighting When you're shopping for lightbulbs, compare lumens and use the Lighting Facts label to be sure you're getting the amount of light, or level of brightness, you want. You can save money and energy while lighting your home and still maintaining good light quantity and quality. Consider energy-efficient lighting options to use the same amount of light for less money. Learn strategies for comparing and buying lighting products and using them efficiently. Featured Lighting Choices to Save You Money Light your home for less money while using the same amount of light. How Energy-Efficient Light Bulbs Compare with Traditional Incandescents Energy-efficient light bulbs are available today and could save you about $50 per year in energy costs when you replace 15 traditional incandescent bulbs in your home.

495

FAQS Job Task Analyses - Industrial Hygiene  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Industrial Hygiene FAQS Industrial Hygiene FAQS STEP 1: Job Task Analysis for Tasks Task (and Number) Source Importance Frequency (1) Plan, observe, and evaluate contractor performance involving industrial hygiene activities to ensure the adequacy and effectiveness of contractor programs such as: * Technical performance (e.g., adequacy of technical practices) * Plans, policies, and procedures * Management controls * Worker training and qualification programs * Occurrence reporting and corrective actions * Occupational health programs FAQS Duties and Responsibilities Paragraph C 4 5 (2) Develop, review, and assess industrial hygiene documentation. FAQS Duties and Responsibilities Paragraph D 4 5 (3) Resolve or facilitate the resolution of industrial hygiene issues.

496

FAQS Job Task Analyses - Instrument and Controls  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

or Working Level Competencies or Working Level Competencies DOE-STD-1162, Instrument & Controls Functional Area Qualification Standard (FAQS) September 2010 STEP 1: Job Task Analysis for Tasks associated with Instrument & Controls Task Source Importance Frequency One: Serve as a subject matter expert and technical resource for instrumentation and control systems. Inspect and evaluate instrumentation and control systems for safe and efficient operation, maintenance, and testing. DOE-STD-1162 Duties and Responsibilities Items B and C 3 2 Two: Review and assess authorization basis documentation. Evaluate instrumentation and control system conformity to authorization basis documentation and other design basis documents. Audit facility instrumentation and control

497

Task-Oriented Maximally Entangled States  

E-Print Network (OSTI)

We introduce the notion of a task-oriented maximally entangled state (TMES). This notion depends on the tasks for which a quantum state is used as the resource. This concept may be more fruitful than that of a general maximally entangled state in the case of a multipartite system. We illustrate this idea by giving an operational definition of maximally entangled states on the basis of communication tasks of teleportation and superdense coding. We also give examples and a procedure to obtain such TMESs for {\\em n}-qubit systems.

Pankaj Agrawal; B. Pradhan

2007-07-29T23:59:59.000Z

498

Architectural Lighting Analysis in Virtual Lighting Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Architectural Lighting Analysis in Virtual Lighting Laboratory Architectural Lighting Analysis in Virtual Lighting Laboratory Speaker(s): Mehlika Inanici Date: July 7, 2003 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Satkartar K. Kinney Virtual Lighting Laboratory is a Radiance-based lighting analysis tool and methodology that proposes transformations in the utilization of computer visualization in lighting analysis and design decision-making. It is a computer environment, where the user has been provided with matrices of illuminance and luminance values extracted from high dynamic range images. The principal idea is to provide the laboratory to the designer and researcher to explore various lighting analysis techniques instead of imposing limited number of predetermined metrics. In addition, it introduces an analysis approach for temporal and spatial lighting

499

How Do You Light Your Home Efficiently? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Light Your Home Efficiently? Light Your Home Efficiently? How Do You Light Your Home Efficiently? July 22, 2009 - 4:30pm Addthis An average household dedicates 11% of its energy budget to lighting. Installing efficient lighting technologies, using task lighting, flipping the switch, and taking advantage of natural daylight can all help you save on your lighting costs. How do you light your home efficiently? Each Thursday, you have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. Please comment with your answers, and also feel free to respond to other comments. Addthis Related Articles How Do You Save Energy in Your Apartment or Rental? How Do You Save Water When Caring for Your Lawn? How Do You Encourage Your Family to Use Less Water

500

FAQS Job Task Analyses - Confinement Ventillation  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

For Expert, Working or Familiarity Level Competencies CVS/PGT FAQ Job Analysis Worksheet for Tasks Task Source Importance Frequency #1 Serves as SME D&R 5 4 #2 Reviews safety documentation D&R 4+ 3- #3 Participates in standards development and interpretation D&R 2 1 #4 Assesses contractor programs and implementation D&R 4 4 #5 Represents Site/DOE at CVS meetings/committees D&R 3 1 #6 Provides oversight of HEPA filter QA programs D&R 4 3+ #7 Evaluate designs D&R 4+ 2 #8 Maintain proficiency D&R 5 1 Importance Scale Frequency How important is this task to the job? How often is the task performed? 0 = Not Performed 0 = Not Performed 1 = Not Important 1 = Every few months to yearly 2 = Somewhat Important 2 = Every few weeks to monthly