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Office of Scientific and Technical Information
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.
Parabolic Molecules Philipp Grohs and Gitta Kutyniok
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
Parabolic Scaling and Curvelets Beyond Parabolic Scaling
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.
Large-angle Parabolic Equation Methods James T. Kirby*
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.
Parabolic geometries BGG sequences
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
Parabolic Quantum Cloak.
??It is shown that the parabolic quantum cloak can be theoretically design by using �transformation design method�. We discuss the possibility to build a parabolic� (more)
Chang, Yu-Hsuan
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.
The parabolic Harnack inequality
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
Progress in parabolic dish technology
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.
Parabolic Raynaud bundles
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
Parabolic-like maps
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
Presenting parabolic subgroups
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, Fran�ois
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
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
Parabolic cylinder functions implemented in Matlab
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
Parabolic flows on complex manifolds
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
Optimal control, parabolic equations, st
state constraints, for parabolic systems have been studied in Casas [20], ... troduced for deriving optimality conditionsfor parabolic problems with pure or mixed.
Parabolic flows on complex manifolds.
??We prove C ? convergence for suitably normalized solutions of the parabolic complex Monge-Amp�re equation on compact Hermitian manifolds. This provides a parabolic proof of� (more)
Parabolic Trough VSHOT Optical Characterization in 2005-2006 (Presentation)
This presentation regarding parabolic trough VSHOT optical characterization describes trough deployment and operation phases including: development, manufacture/installation, and maintenance/operation.
Wendelin, T.
Solar parabolic dish annual technology evaluation report. Fiscal year 1982
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
Parabolic concentrating collector: a tutorial
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.
On parabolic Whittaker functions
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
Oblezin, Sergey
NREL: TroughNet - Parabolic Trough Power Plant System Technology
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.
Electromagnetic Casimir forces of parabolic cylinder and knife-edge geometries
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
NREL: TroughNet - U.S. Parabolic Trough Power Plant Data
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,...
Properties of parabolic Sobolev and parabolic Besov spaces
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
Abstract. A non-elementary M�bius 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
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
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)
A compound parabolic concentrator
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.
Parabolic submanifolds of rank two
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
Parabolic k-ample bundles
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.
Solar parabolic dish technology annual evaluation report. Fiscal year 1983
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.
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
Parabolic John-Nirenberg spaces
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
Orthogonal parabolic reflector systems
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.
Solar thermal parabolic dish systems: technology and applications
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.
NREL: TroughNet - Parabolic Trough System and Component Testing
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
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)
Electromagnetic Casimir Forces of Parabolic Cylinder and Knife-Edge Geometries
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
Technical and economic analysis of parabolic trough concentrating solar thermal power plant.
??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 .
Experimental parabolic trough collector performance characterization
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.
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
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
STUDIA MATHEMATICA 193 (3) (2009) On the parabolic-elliptic limit of the doubly parabolic
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
On the parabolic-elliptic limit of the doubly parabolic KellerSegel system
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
MODULI SPACES OF PARABOLIC HIGGS BUNDLES AND PARABOLIC K(D) PAIRS OVER SMOOTH CURVES: I HANS U. BODEN AND K �?? 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.
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,
A Relation Between the Parabolic . . .
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
Parabolic subgroups of Garside groups
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
Courant Algebroids in Parabolic Geometry
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
The Parabolic-Trigonometric Functions
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
SunShot Initiative: Parabolic Trough
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,...
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
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
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
Shenandoah parabolic dish solar collector
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.
Threshold results for semilinear parabolic systems
A threshold result was proved in this paper for semilinear parabolic system with pure power type nonlinearities
Xie, Qiuyi Dai Haiyang He Junhui
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
Coupled Parabolic Equations for Wave Propagation
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
The parabolic Mandelbrot set Pascale ROESCH
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
The near parabolic renormalization Inou and Shishikura
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
Degenerate Parabolic Stochastic Partial Differential Equations
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
Release Version Parabolic Dish Microphone System
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.
Plane and parabolic solar panels
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
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.
Sales, J H O
Universal estimate of the gradient for parabolic equations
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
Nonlocal Operators, Parabolic-type Equations, and Ultrametric Random Walks
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. Chac�n-Cortes; W. A. Z��iga-Galindo
NREL: TroughNet - Parabolic Trough Workshops
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
THE PARABOLIC-PARABOLIC KELLER-SEGEL SYSTEM WITH CRITICAL DIFFUSION AS A GRADIENT FLOW IN Rd
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
Parabolic systems and an underlying Lagrangian.
??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, T�rkay
Parabolic Weingarten surfaces in hyperbolic space
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.
L�pez, Rafael
Parabolic equations without a minimum principle.
??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
Performance of a parabolic trough solar collector.
??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
Bibliography Parabolic Geometries and Weyl connections Nearly invariant calculus (Wunsch's) nearly invariant calculus for parabolic
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
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
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
A discrete BGK approximation for strongly degenerate parabolic problems
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
A Note on Parabolic Subgroups of a Coxeter Group
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
Parabolic Deligne-Lusztig varieties
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, Fran�ois
Steam generation in compound parabolic concentrator collectors
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.
NREL: TroughNet - Parabolic Trough Power Plant Market, Economic...
Parabolic Trough Power Plant Market, Economic Assessment and Deployment Parabolic trough technology is the most commercially mature, large-scale solar power technology in the...
DOE Finalizes $1.45 Billion Loan Guarantee for One of the World...
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
has been finalized for Abengoa Solar Inc.'s Solana project, the world's largest parabolic trough concentrating solar plant. Located near Gila Bend, Arizona, the 250-megawatt...
QED with a parabolic mirror
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. Bern�d; M. Stobi?ska; L. L. S�nchez-Soto; G. Leuchs
S-Parabolic manifolds A. Aytuna and A. Sadullaev
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
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
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
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 �? 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
On a parabolic logarithmic Sobolev inequality H. Ibrahim ,,, R. Monneau
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, Régis
Parabolic Trough Solar Power Plant Simulation Model: Preprint
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.
Parabolic Trouogh Optical Characterization at the National Renewable Energy Laboratory
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.
Definition: Parabolic trough | Open Energy Information
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
Rational Approximation for a Quasilinear Parabolic Equation
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
Parabolic Trough Solar Thermal Electric Power Plants
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.
Parabolic equations without a minimum principle
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 ...
Classification of Invariant Differential Operators for Non-Compact Lie Algebras via Parabolic Relations
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
Parabolic trough solar collectors : design for increasing efficiency
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-
Design considerations for parabolic-cylindrical solar collectors
This report presents in some detail the various significant factors which influence the design of parabolic-cylindrical solar collectors.
Treadwell, G.W.
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
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
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
Convergence properties of the local defect correction method for parabolic
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
Parabolic PDEs and Deterministic Games Robert V. Kohn
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
Generation of parabolic pulses and applications for optical telecommunications
Generation of parabolic pulses and applications for optical telecommunications Christophe Finot firstname.lastname@example.com 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
Di usive Kinetic Explicit Schemes for Nonlinear Degenerate Parabolic Systems
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
Curvilinear parabolic approximation for surface wave transformation with wavecurrent interaction
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
Theory of parabolic pulse generation in tapered Anton I. Latkin
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.
Parabolic surfaces in hyperbolic space with constant Gaussian curvature
Parabolic surfaces in hyperbolic space with constant Gaussian curvature Rafael L´opez firstname.lastname@example.com 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
López, Rafael
On Parallel Asynchronous HighOrder Solutions of Parabolic PDEs
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
Compound parabolic concentrators for narrowband wireless infrared receivers
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.
Rotational and Parabolic Surfaces in PSL2(R, ) and Applications
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
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
Parabolic resonances and instabilities Vered Rom-Kedara)
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
· 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
Elastic approximation for a solar parabolic February 29, 2012
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
On a parabolic operator of dissipative systems
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
Parabolic systems with coupled boundary conditions
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
NREL: TroughNet - Parabolic Trough Technology Models and Software Tools
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
Piecewise parabolic negative magnetoresistance of two-dimensional electron gas with triangular antidot lattice
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: firstname.lastname@example.com; 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)
Analysis of the influence of geography and weather on parabolic trough solar collector design
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.
Parabolic Sturmians approach to the three-body continuum Coulomb problem
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
Validation of the FLAGSOL parabolic trough solar power plant performance model
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)
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
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
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
Parabolic Trough Organic Rankine Cycle Power Plant
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.
Poincar'e polynomial of the moduli spaces of parabolic bundles
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.
Optimal Heat Collection Element Shapes for Parabolic Trough Concentrators
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
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 ...
Estimates in the Generalized Morrey Space for Linear Parabolic Systems.
??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
Long-term average performance benefits of parabolic trough improvements
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.
Simplified Methodology for Designing Parabolic Trough Solar Power Plants.
??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
Parabolic trough solar collectors : design for increasing efficiency.
??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)
?? 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)
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 ...
post-pareto analysis for multiobjective parabolic control systems
Jul 29, 2012 ... POST-PARETO ANALYSIS FOR MULTIOBJECTIVE PARABOLIC CONTROL SYSTEMS. Henri Bonnel (bonnel ***at*** univ-nc.nc). Abstract: In�...
Parabolic Trough Solar Thermal Electric Power Plants (Fact Sheet)
This fact sheet provides an overview of the potential for parabolic trough solar thermal electric power plants, especially in the Southwestern U.S.
Field Survey of Parabolic Trough Receiver Thermal Performance: Preprint
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.
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
Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough...
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...
Alignment method for parabolic trough solar concentrators
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)
Numerical Schemes for Rough Parabolic Equations
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: email@example.com [Universite de Nancy 1, Institut Elie Cartan Nancy (France)
Overview of software development at the Parabolic Dish Test Site
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.
An Optical Characterization Technique for Parabolic Trough Solar Collectors Using Images of the Absorber Reection.
?? 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
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
A new parabolic trough solar collector P. Kohlenbach1
) 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
NREL: TroughNet - Parabolic Trough Technology Solar Resource Data and Tools
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,
Parabolic refined invariants and Macdonald polynomials
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
Single-photon single-ion interaction in free space configuration in front of a parabolic mirror
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
Self-similar parabolic plasmonic beams Arthur R. Davoyan,1,2,
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
NREL: TroughNet - Parabolic Trough Technology Overview
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
Parabolic sturmians approach to the three-body continuum Coulomb problem
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: firstname.lastname@example.com [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)
Gas Turbine/Solar Parabolic Trough Hybrid Design Using Molten Salt Heat Transfer Fluid: Preprint
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.
Parabolic Equations and Markov Processes Over p-adic Fields
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
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
A T-Schottky group is a discrete group of M�bius 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
Shock stability analysis for Parabolized Navier-Stokes equations
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
NREL: TroughNet - Parabolic Trough Thermal Energy Storage Technology
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...
Guidelines for reporting parabolic trough solar electric system performance
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.
NREL: TroughNet - 2007 Parabolic Trough Technology Workshop
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.
Parabolic Whittaker Functions and Topological Field Theories I
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
Solargenix Energy Advanced Parabolic Trough Development
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.
Parabolic Trough Receiver Heat Loss Testing (Poster)
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.
Current and Future Economics of Parabolic Trough Technology
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.
Does the fully parabolic quasilinear 1D Keller-Segel system enjoy long-time asymptotics analogous to its parabolic-elliptic simplification?
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
Interpretation of parabolic arcs in pulsar secondary spectra
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
The first Chern form on moduli of parabolic bundles
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
Mean wind forces on parabolic-trough solar collectors
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.
Status of APS 1-Mwe Parabolic Trough Project
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.
Federal technology alert. Parabolic-trough solar water heating
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.
SunShot Initiative: Advanced Low-Cost Receivers for Parabolic...
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SunShot Initiative: High-Concentration, Low-Cost Parabolic Trough...
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...
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
The parabolic trigonometric functions and the Chebyshev radicals
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
Natural convective studies within a compound parabolic concentrator enclosure
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.
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
$C^{1,\\al}$ regularity of solutions to parabolic Monge-Amp\\'ere equations
We study interior $C^{1, \\al}$ regularity of viscosity solutions of the parabolic Monge-Amp\\'ere equation
Daskalopoulos, Panagiota
Executive Summary: Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts
Sargent& Lundy LLC conducted an independent analysis of parabolic trough and power tower solar technology cost and performance.
Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts
Sargent and Lundy LLC conducted an independent analysis of parabolic trough and power tower solar technology cost and performance.
BSDE driven by Dirichlet Process and Semi-linear Parabolic PDE.
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
Operator-splitting finite element algorithms for computations of high-dimensional parabolic problems
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
The parabolic Anderson model with heavy-tailed potential Peter Morters
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
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
A Sparse Grid SpaceTime Discretization Scheme for Parabolic Problems
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
Parabolic equation modeling of high frequency acoustic transmission with an evolving sea surface
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
Convergence of Singular Limits for Multi-D Semilinear Hyperbolic Systems to Parabolic Systems
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
Parabolic Kazhdan-Lusztig R-polynomials for tight quotients of the symmetric groups 1
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
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
Elastic parabolic equation solutions for underwater acoustic problems using seismic sources
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
Theory of Parabolic Pulse Propagation in Nonlinear Dispersion Decreasing Optical Fiber Amplifiers
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
Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry and sediment thickness
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
Parallelizing Implicit Algorithm for TimeDependent Problems by Parabolic Domain
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
PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1, Belgium, Email: firstname.lastname@example.com ABSTRACT Gravity changes during partial-G parabolic flights requires the understanding of how the CVS adapts to gravity changes. Parabolic flights are one
PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1 Leuven, Belgium, Email: firstname.lastname@example.com ABSTRACT Gravity changes during partial-G parabolic to reduce postflight orthostatic intolerance. Key words: parabolic flight; heart rate; blood pressure
Parabolic geometries and normal Weyl structures First BGG operators and special solutions
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Harnack Inequalities for NonNegative Solutions to Degenerate and Singular Parabolic Partial
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Gianazza, Ugo
Influence of the initial phase profile on the asymptotic self-similar parabolic dynamics
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
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
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
Stability and Freezing of Waves in Nonlinear Hyperbolic-Parabolic Systems
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
Velocity-jump processes with a finite number of speeds and their asymptotically parabolic nature
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
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
Two parabolic equations for propagation in layered poro-elastic media
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
Parabolic laws of the surrounded-atom model from ab initio calculations on clusters
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
Parabolic lines and caustics in weakly anisotropic solids 9iFODY##9DYU\\XN
117 Parabolic lines and caustics in weakly anisotropic solids 9iFODY##9DYU\\þXN *firstname.lastname@example.com 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
Self-accelerating parabolic beams in quadratic nonlinear media Ido Dolev, Ana Libster, and Ady Arie
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Arie, Ady
Repeated games for eikonal equations, integral curvature flows and non-linear parabolic
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
Flux Distribution of a Single-Axis Tracking Parabolic Trough Array with Photovoltaic Receiver
Flux Distribution of a Single-Axis Tracking Parabolic Trough Array with Photovoltaic Receiver G 0200 Australia E-mail: email@example.com Abstract Single-axis tracking parabolic troughs Long arrays of single-axis tracking parabolic troughs with a fluid filled absorber are a well
Yearly distributed insolation model and optimum design of a two dimensional compound parabolic concentrator
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)
The Nonlinear Evolution of Disturbances to a Parabolic Jet
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
Theoretical Investigation of the Closed Type Parabolic Trough
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
Compound parabolic concentrator with cavity for tubular absorbers
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)
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.
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
Parabolic Trough Solar Power for Competitive U.S. Markets
Henry W. Price
Secondary concentrators for parabolic dish solar thermal power systems
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.
Nomographic methodology for use in performance trade-off studies of parabolic dish solar power modules
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.
Prediction and optimization of the performance of parabolic solar dish concentrator with sphere receiver using analytical function
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
A Linear Parabolic Trough Solar Collector Performance Model
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.
Parabolic-Dish Solar Concentrators of Film on Foam
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
Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint
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.
2 Technology Description: Solar Thermal Parabolic Trough Solar Thermal
� 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
Material and process screening as applied to a reinforced plastic parabolic trough concentrator module
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.)
Convection heat loss from cavity receiver in parabolic dish solar thermal power system: A review
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)
Measurement of Hydrogen Purge Rates in Parabolic Trough Receiver Tubes: Preprint
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.
Development and testing of Parabolic Dish Concentrator No. 1
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.
Irrigation market for solar-thermal parabolic-dish systems
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.
Gas Turbine/Solar Parabolic Trough Hybrid Designs: Preprint
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.
Parabolic-Trough Technology Roadmap: A Pathway for Sustained Commercial Development and Deployment of Parabolic-Trough Technology
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.
Video Scanning Hartmann Optical Testing of State-of-the-Art Parabolic Trough Concentrators: Preprint
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.
Deformation of a thin, elastic plate to a deep parabolic cylinder
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.
NaNO3-KNO3 Ternary Molten Salts for Parabolic Trough
Presentation Title, Thermodynamic Properties of Novel Low Melting Point LiNO3- NaNO3-KNO3 Ternary Molten Salts for Parabolic Trough Solar Power�...
Two-tank indirect thermal storage designs for solar parabolic trough power plants.
??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.
Mechanical development of the actuation system of a parabolic solar trough.
??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)
Parabolic Trough Solar System Piping Model: Final Report, 13 May 2002 ? 31 December 2004
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.
On the use of the parabolic concentration profile assumption for a rotary desiccant dehumidifier
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
World Labs
Particle Physics Labs Worldwide Elementary Particles Detectors Accelerators Visit World Labs Brookhaven National Laboratory-RHIC CERN -- European Organization for Nuclear Research...
Inhomogeneous parabolic equations on unbounded metric measure spaces
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
Parabolic trough collector systems for thermal enhanced oil recovery
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.
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.
The solvability of the first initial-boundary problem for parabolic and degenerate parabolic equations in domains with a conical point
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)
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 Poincar� polynomials depend on the system of weights of the parabolic bundle. 1.
Marina Logares
A Parallel Scheme of the Split-Step Fourier Transform Method for Solving Parabolic Wave Equation
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
Theory of Parabolic Arcs in Interstellar Scintillation Spectra
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
The Piecewise Parabolic Method for Multidimensional Relativistic Fluid Dynamics
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
Development effort of sheet molding compound (SMC) parabolic trough panels
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.
New high-flux two-stage optical designs for parabolic solar concentrators
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))
Domain Decomposition via Explicit/Implicit Time Marching 1 Polynomial Collocation Using a Domain Decomposition Solution to Parabolic
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
Spectral inequalities for non-selfadjoint elliptic operators and application to the null-controllability of parabolic systems
-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
Parabolic focal conics and polygonal textures in lipid liquid crystals (*) S. A. Asher and P. S. Pershan
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.
The symmetric parabolic resonance This article has been downloaded from IOPscience. Please scroll down to see the full text article.
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
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, VOL. 53, NO. 7, AUGUST 2008 1575 Adaptive Boundary Control for Unstable Parabolic
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
IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 34, NO. 4, OCTOBER 2009 617 Extension of the Rotated Elastic Parabolic Equation
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
Near-field enhancement of metal nano-particle based on the light focusing by the micro-parabolic mirror
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
Characteristics of quadratic electro-optic effects and electro-absorption process in CdSe parabolic quantum dots
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
World energy consumption
Historical and projected world energy consumption information is displayed. The information is presented by region and fuel type, and includes a world total. Measurements are in quadrillion Btu. Sources of the information contained in the table are: (1) history--Energy Information Administration (EIA), International Energy Annual 1992, DOE/EIA-0219(92); (2) projections--EIA, World Energy Projections System, 1994. Country amounts include an adjustment to account for electricity trade. Regions or country groups are shown as follows: (1) Organization for Economic Cooperation and Development (OECD), US (not including US territories), which are included in other (ECD), Canada, Japan, OECD Europe, United Kingdom, France, Germany, Italy, Netherlands, other Europe, and other OECD; (2) Eurasia--China, former Soviet Union, eastern Europe; (3) rest of world--Organization of Petroleum Exporting Countries (OPEC) and other countries not included in any other group. Fuel types include oil, natural gas, coal, nuclear, and other. Other includes hydroelectricity, geothermal, solar, biomass, wind, and other renewable sources.
Optimal Control of a Parabolic Equation with Dynamic Boundary Condition
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: firstname.lastname@example.com; Krumbiegel, K., E-mail: email@example.com [Weierstrass Institute for Applied Mathematics and Stochastics, Nonlinear Optimization and Inverse Problems (Germany); Rehberg, J., E-mail: firstname.lastname@example.com [Weierstrass Institute for Applied Mathematics and Stochastics, Partial Differential Equations (Germany)
Test results, Industrial Solar Technology parabolic trough solar collector
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)
Use of compound parabolic concentrator for solar energy collection
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.
Fifth parabolic dish solar thermal power program annual review: proceedings
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.
Thermal design of compound parabolic concentrating solar-energy collectors
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.
Development of Molten-Salt Heat Transfer Fluid Technology for Parabolic Trough Solar Power Plants - Public Final Technical Report
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.
arXiv:math/0302209v1[math.AG]18Feb2003 THETA FUNCTIONS ON THE MODULI SPACE OF PARABOLIC
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
SHADE: a computer model for evaluating the optical performance of two-axis tracking parabolic concentrators
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.
Wind Tunnel Tests of Parabolic Trough Solar Collectors: March 2001--August 2003
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.
The parabolic Sturmian-function basis representation of the six-dimensional Coulomb Green's function
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
Custom Engineering parabolic glass reflector for the Sandia prototype solar collector
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.
Mechanical development of the actuation system of a parabolic solar trough
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 ...
Heat-Loss Testing of Solel's UVAC3 Parabolic Trough Receiver
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.
Parabolic-Trough Solar Water Heating--FTA, 022798m FTA trough
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
Stability in terms of two measures for a class of semilinear impulsive parabolic equations
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
Optical analysis and optimization of parabolic-trough collectors: a user's guide
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.
Comparison of Fresnel lenses and parabolic mirrors as solar energy concentrators
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.
The heat-balance integral method by a parabolic profile with unspecified exponent: Analysis and Benchmark Exercises
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
Slope Error Measurement Tool for Solar Parabolic Trough Collectors: Preprint
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.
Conservation Laws and Potential Symmetries of Linear Parabolic Equations
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
Mechanism of Hydrogen Formation in Solar Parabolic Trough Receivers
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.
Experimental natural convective studies within a compound parabolic concentrator enclosure
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.
Two dimensional compound parabolic concentrating collectors. Final report
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.
5 World Oil Trends WORLD OIL TRENDS
5 World Oil Trends Chapter 1 WORLD OIL TRENDS INTRODUCTION In considering the outlook for California's petroleum supplies, it is important to give attention to expecta- tions of what the world oil market. Will world oil demand increase and, if so, by how much? How will world oil prices be affected
Numerical study on coupled fluid flow and heat transfer process in parabolic trough solar collector tube
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)
Secondary and compound concentrators for parabolic-dish solar-thermal power systems
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.
Design of a Transpired Air Heating Solar Collector with an Inverted Perforated Absorber and Asymmetric Compound Parabolic Concentrator.
?? 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
2008 world direct reduction statistics
This supplement discusses total direct reduced iron (DRI) production for 2007 and 2008 by process. Total 2008 production by MIDREX(reg sign) direct reduction process plants was over 39.8 million tons. The total of all coal-based processes was 17.6 million tons. Statistics for world DRI production are also given by region for 2007 and 2008 and by year (1970-2009). Capacity utilization for 2008 by process is given. World DRI production by region and by process is given for 1998-2008 and world DRI shipments are given from the 1970s to 2008. A list of world direct reduction plants is included.
Wind load design methods for ground-based heliostats and parabolic dish collectors
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.)
Determination of a control parameter in a one-dimensional parabolic equation using the moving least-square approximation
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
Fully discrete FEM-BEM method for a class of exterior nonlinear parabolic-elliptic problems in 2D
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
Mar�a Gonz�lez
Erlangen Program at Large--2: Inventing a wheel. The parabolic one
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
Determination of freeze-protection heat loss from a parabolic trough solar system
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.
On the iterated Crank-Nicolson for hyperbolic and parabolic equations in numerical relativity
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
Nexant Parabolic Trough Solar Power Plant Systems Analysis; Task 3: Multiple Plants at a Common Location, 20 January 2005 - 31 December 2005
Subcontract report by Nexant, Inc., regarding a system analysis of multiple solar parabolic trough plants at a common location.
Kelly, B.
IASTED Conf. on Modeling, Identification and Control, February 14-17, 2000, Innsbuck, Austria 296 NYQUIST STABILITY TEST FOR A PARABOLIC PARTIAL
NYQUIST STABILITY TEST FOR A PARABOLIC PARTIAL DIFFERENTIAL EQUATION MIKLOS VAJTA Dept. of email@example.com 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
Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B. Oliveira
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
Photovoltaic concentrator application experiment to be located at Sea World Park, Orlando, Florida. Phase I. System Design. Final report, June 1, 1978-February 28, 1979
The General Electric/Sea World Photovoltaic Concentrator Application Experiment will be located at Sea World's Marine Park near Orlando, Florida. The experiment will consist of nine azimuth-tracking turntable arrays, each containing twenty-four elevation-tracking parabolic trough PV concentrators of a type developed on this contract. The system will produce a peak power output of 330 kW and an annual net electrical energy of 355 MWh corresponding to an annual direct normal insolation of 1375.5 kWh/m/sup 2/. A line-commutated DC/AC inverter controlled to operate at the solar array maximum power point will deliver three-phase power through a bidirectional transformer to a 13-kilovolt line serving the Sea World Park. In addition to generating electrical power, the system will produce 3.56 x 10/sup 5/ ton-hours of cooling for air conditioning a nearby shark exhibit by supplying collected thermal energy to a lithium-bromide absorption chiller. With credit included for the amount of electricity that would be required to produce this cooling by a vapor compression cycle, the overall system efficiency is estimated to be 11.7 percent.
Kirpich, A.S.
world bank | OpenEI
world bank world bank Dataset Summary Description No description given. Source World Bank Date Released Unknown Date Updated Unknown Keywords coal energy imports energy production energy use fossil fuels Fuel global Hydroelectric international nuclear oil renewables statistical statistics world bank Data application/zip icon Data in XML Format (zip, 1 MiB) application/zip icon Data in Excel Format (zip, 1.3 MiB) Quality Metrics Level of Review Peer Reviewed Comment Temporal and Spatial Coverage Frequency Time Period 1970 - 2007 License License Other or unspecified, see optional comment below Comment Summary of Usage Terms ---------------------- You are free to copy, distribute, adapt, display or include the data in other products for commercial and noncommercial purposes at no cost subject to certain limitations summarized below. You must include attribution for the data you use in the manner indicated in the metadata included with the data. You must not claim or imply that The World Bank endorses your use of the data by or use The World Bank's logo(s) or trademark(s) in conjunction with such use. Other parties may have ownership interests in some of the materials contained on The World Bank Web site. For example, we maintain a list of some specific data within the Datasets that you may not redistribute or reuse without first contacting the original content provider, as well as information regarding how to contact the original content provider. Before incorporating any data in other products, please check the list: Terms of use: Restricted Data. The World Bank makes no warranties with respect to the data and you agree The World Bank shall not be liable to you in connection with your use of the data. Links ----- Summary of Terms: http://data.worldbank.org/summary-terms-of-use Detailed Usage Terms: http://www.worldbank.org/terms-datasets
Parabolic Trough Power for the California Competitive Market (Presentation)
This presentation includes discusses the restructuring of the California power market and the resulting impacts.
Price, H.; Cable, B.
Homogenization of a degenerate parabolic problem in a highly heterogeneous medium with highly anisotropic fibers
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
The asymptotics of a solution of a parabolic equation as time increases without bound
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
Solution blow-up for a class of parabolic equations with double nonlinearity
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)
Brief paper: An LMI approach to H? boundary control of semilinear parabolic and hyperbolic systems
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
Nuclear spin dynamics in parabolic quantum wells Ionel Tifrea* and Michael E. Flatte
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.
The cylindrical parabolic mirror as reflector for solar collectors. Efficiencies and optimization
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.
hal-00177601,version2-30Oct2007 A closed parabolic trough solar collector
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
Cooling for Parabolic Trough Power Plants: Overview (Presentation)
This presentation discusses water requirements for power generation and includes an analysis of wet/dry cooling.
CIA-The World Factbook | Open Energy Information
CIA-The World Factbook CIA-The World Factbook Jump to: navigation, search Tool Summary LAUNCH TOOL Name: CIA-The World Factbook Agency/Company /Organization: United States Central Intelligence Agency Topics: Background analysis Resource Type: Dataset Website: www.cia.gov/library/publications/the-world-factbook/index.html Cost: Free CIA-The World Factbook Screenshot References: CIA-The World Factbook[1] "The World Factbook provides information on the history, people, government, economy, geography, communications, transportation, military, and transnational issues for 266 world entities. Our Reference tab includes: maps of the major world regions, as well as Flags of the World, a Physical Map of the World, a Political Map of the World, and a Standard Time Zones of the World map."
IEA World Energy Outlook | Open Energy Information
IEA World Energy Outlook IEA World Energy Outlook Jump to: navigation, search Tool Summary Name: IEA World Energy Outlook Agency/Company /Organization: International Energy Agency Sector: Energy Focus Area: Conventional Energy, Energy Efficiency, Renewable Energy Topics: Market analysis, Technology characterizations References: World Energy Outlook[1] The 2010 "edition of the World Energy Outlook - the International Energy Agency's flagship publication and leading source of analysis of global energy trends - presents updated projections of energy demand, production, trade and investment, fuel by fuel and region by region to 2035. WEO-2010 includes, for the first time, the result of a new scenario that takes account of the recent commitments that governments have made to
Drivers of Residual Estuarine Circulation in Tidally Energetic Estuaries: Straight and Irrotational Channels with Parabolic Cross Section
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
Homogenization of a singularly perturbed degenerated parabolic equation and application to seabed dune and megaripple morphodynamics in tided environment
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
Reducing the Cost of Energy from Parabolic Trough Solar Power Plants: Preprint
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.
Parabolic Coordinates and the Hydrogen Atom in Spaces H_{3} and S_{3}
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
Near-term improvements in parabolic troughs: an economic and performance assessment
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.
Analysis of static and quasi-static cross compound parabolic concentrators
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.
Summary World Wind Energy Data (from World on the Edge) | OpenEI
the Earth Policy Institute. This wind energy dataset includes the following cumulative installed wind power capacity datasets: World (1980 - 2009); Top ten countries (1980 -...
Peculiarities of parabolic-barrier penetrability and thermal decay rate with the quantum diffusion approach
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)
Stabilization of solutions of quasilinear second order parabolic equations in domains with non-compact boundaries
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)
The relative isoperimetric inequality on a conformally parabolic manifold with boundary
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)
Heat Transfer Analysis and Modeling of a Parabolic Trough Solar Receiver Implemented in Engineering Equation Solver
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.
LINSOL: a model for predicting the optical performance of parabolic trough solar thermal systems
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.
Dielectric compound parabolic concentrating solar collector with a frustrated total internal reflection absorber
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.
Dielectric compound parabolic concentrating solar collector with frustrated total internal reflection absorber
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.
Investigation on the prediction of thermal performance of compound parabolic concentrators
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.
Energetic protons from an ultraintense laser interacting with a symmetric parabolic concave target
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)
DOE Finalizes $1.45 Billion Loan Guarantee for One of the World's Largest
Finalizes $1.45 Billion Loan Guarantee for One of the World's Finalizes $1.45 Billion Loan Guarantee for One of the World's Largest Solar Generation Plants DOE Finalizes $1.45 Billion Loan Guarantee for One of the World's Largest Solar Generation Plants December 21, 2010 - 12:00am Addthis Washington D.C. - U.S. Energy Secretary Steven Chu today announced a $1.45 billion loan guarantee has been finalized for Abengoa Solar Inc.'s Solana project, the world's largest parabolic trough concentrating solar plant. Located near Gila Bend, Arizona, the 250-megawatt (MW) project is the first large-scale solar plant in the United States capable of storing energy it generates. Solana will produce enough energy to serve 70,000 households and will avoid the emissions of 475,000 tons of carbon dioxide per year compared to a natural gas burning power plant.
Although tidally locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric transport of water from the dayside to the nightside, where it is precipitated as snow and trapped as ice. Since ice only slowly flows back to the dayside upon accumulation, the resulting hydrological cycle can trap a large amount of water in the form of nightside ice. Using ice sheet dynamical and thermodynamical constraints, I illustrate how planets with less than about a quarter the Earth's oceans could trap most of their surface water on the nightside. This would leave their dayside, where habitable conditions are met, potentially dry. The amount and distribution of residual liquid water on the dayside depend on a variety of geophysical factors, including the efficiency of rock weathering at regulating atmospheric CO{sub 2} as dayside ocean basins dry up. Water-trapped worlds with dry daysides may offer similar advantages as land planets for habitability, by contrast with worlds where more abundant water freely flows around the globe.
Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
Garbage Collecting the World
Distributed symbolic computations involve the existence of remote references allowing an object, local to a processor, to designate another object located on another processor. To reclaim inaccessible objects is the non trivial task of a distributed Garbage Collector (GC). We present in this paper a new distributed GC algorithm which (i) is faulttolerant, (ii ) is largely independent of how a processor garbage collects its own data space, (iii ) does not need centralized control nor global stop-the-world synchronization, (iv) allows for multiple concurrent active GCs, (v) does not require to migrate objects from processor to processor and (vi) eventually reclaims all inaccessible objects including distributed cycles. These results are mainly obtained through the concept of a group of processors (or processes). Processors of a same group cooperate together to a GC inside this group; this GC is conservative with respect to the outside of the group. A processor contributes to the glob...
Bernard Lang; Christian Queinnec; Jos� Piquer
488 Brazilian Journal of Physics, vol. 36, no. 2A, June, 2006 Spin Valve Effect and Hall Resistance in a Wide Parabolic Well
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
Summary World Solar Energy Data (from World on the Edge) | OpenEI
Solar Energy Data (from World on the Edge) Solar Energy Data (from World on the Edge) Dataset Summary Description This dataset presents summary information related to world solar energy. It is part of a supporting dataset for the book World On the Edge: How to Prevent Environmental and Economic Collapse by Lester R. Brown, available from the Earth Policy Institute. This solar energy dataset includes the following: World solar PV production (1975 - 2009); Annual solar PV production by country (1995 - 2009); Solar PV production in the US (1976 - 2009); World cumulative solar PV installations (1998 - 2009); Annual solar PV installations in selected countries and the world (1998 - 2009); Cumulative solar PV installations in the US (1998 - 2009) and EU (1998 - 2009); World installed concentrating solar thermal power capacity (1980 - 2009); solar water and space heating area in selected countries (2008) and top ten countries (2008).
Summary World Biofuels Energy Data (from World on the Edge) | OpenEI
Biofuels Energy Data (from World on the Edge) Biofuels Energy Data (from World on the Edge) Dataset Summary Description This dataset presents summary information related to world biofuels production. It is part of a supporting dataset for the book World On the Edge: How to Prevent Environmental and Economic Collapse by Lester R. Brown, available from the Earth Policy Institute. This biofuels dataset includes the following ethanol production data: World (1975 - 2010); ten leading countries in the world (2010); U.S. (1978 - 2010); Brazil (1975 - 2010); China (2002 - 2010); E.U. (1992 - 2010), as well as Corn production and use for ethanol in the U.S. (1980 - 2010). Also included is biodiesel production data for: World (1991 - 2010); five leading countries (2010); U.S. (2000 - 2010); and the E.U. (2000 - 2010).
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
Subcontract report by Nexant, Inc., regarding a system analysis comparing solar parabolic trough plants with wet and dry rankine cycle heat rejection.
World Wide Web Information Servers
World Wide Web Information Servers World Wide Web Information Servers Lawrence Berkeley Laboratory recently announced a gopher and World Wide Web site. To get to the web site, telnet to www.lbl.gov, login: www. Access is provided to LBL's gopher, library catalog, and publication list. The Center is funding the implementation of a WWW network node for on-line access to publications, databases, and documents full of hypermedia links to other documents or information systems from the Energy & Environment Division. Full implementation is expected by May 1994, and will include access to a variety of information from all the research programs and centers. The technology transfer project calls for this newsletter to be published on WWW using the Mosaic interface under development at the National Center
Modeling of a Parabolic Trough Solar Field for Acceptance Testing: A Case Study
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.
Proceedings of the 5th World Conference on Detergents
5th World Conference on Detergents, includes CD-ROM. Proceedings of the 5th World Conference on Detergents Surfactants and Detergents aocs articles Detergents division divisions fabric fats home care jaocs journal jsd laundry methods oils papers personal
Omnium-G parabolic dish optical efficiency: a comparison of two independent measurement techniques
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.
Initial evolution of supports of solutions of quasilinear parabolic equations with degenerate absorption potential
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
The Cauchy problem for a quasilinear parabolic equation with gradient absorption
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)
Proceedings: fourth parabolic-dish solar-thermal power program review
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.
Frequency response analysis of fluid control systems for parabolic-trough solar collectors
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.
Analytical Approach Treating Three-Dimensional Geometrical Effects of Parabolic Trough Collectors: Preprint
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.
Performance and testing of a stationary concentrating collector. [Compound parabolic concentrators coupled to tubular evacuated receivers
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
Measured performances of curved inverted-vee, absorber compound parabolic concentrating solar-energy collectors
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))
The performance of bifacial solar cells in prism-coupled compound parabolic concentrators
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))
Analysis of the incidence angle of the beam radiation on CPC. [Compound Parabolic Concentrator
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))
An experimental study of free convection in compound parabolic concentrator (CPC) cavities
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.
Development effort on sheet-molding compound (SMC) parabolic-trough panels
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.
A review of test results on parabolic dish solar thermal power modules with dish-mounted rankine engines and for production of process steam
This paper presents results of development testing of various solar thermal parabolic dish modules and assemblies. Most of the tests were at modules and assemblies that used a dish-mounted, organic Rankine cycle turbine for production of electric power. Some tests were also run on equipment for production of process steam or for production of electricity using dish-mounted reciprocating steam engines. These tests indicate that early modules achieve efficiencies of about 18 percent in converting sunlight to electricity (excluding the inverter but including parasitics). A number of malfunctions occurred. The performance measurements, as well as the malfunctions and other operating experience, provided information that should be of value in developing systems with improved performance and reduced maintenance.
Jaffe, L.D.
International Energy Outlook 2006 - World Oil Markets
Gasoline and Diesel Fuel Update (EIA)
Oil Markets Oil Markets International Energy Outlook 2006 Chapter 3: World Oil Markets In the IEO2006 reference case, world oil demand increases by 47 percent from 2003 to 2030. Non-OECD Asia, including China and India, accounts for 43 percent of the increase. In the IEO2006 reference case, world oil demand grows from 80 million barrels per day in 2003 to 98 million barrels per day in 2015 and 118 million barrels per day in 2030. Demand increases strongly despite world oil prices that are 35 percent higher in 2025 than in last years outlook. Much of the growth in oil consumption is projected for the nations of non-OECD Asia, where strong economic growth is expected. Non-OECD Asia (including China and India) accounts for 43 percent of the total increase in world oil use over the projection period.
Summary World Oil Data (from World on the Edge) | OpenEI
Oil Data (from World on the Edge) Oil Data (from World on the Edge) Dataset Summary Description This dataset presents summary information related to world oil. It is part of a supporting dataset for the book World On the Edge: How to Prevent Environmental and Economic Collapse by Lester R. Brown, available from the Earth Policy Institute. This world oil dataset includes the following data: World oil production (1950 - 2009): Top 20 producing countries (2009); Oil production in U.S. (1900 - 2009); Oil consumption in U.S. (950 - 2010); Oil consumption in China (1965 - 2009); Oil consumption in E.U. (1965 - 2009); Top 20 oil importing countries (2009); World's 20 largest oil discoveries; Real price of gasoline (2007); Retail gas prices by country (2008); and fossil fuel consumption subsidies (2009).
Well-posedness of a parabolic moving-boundary problem in the setting of Wasserstein gradient flows
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
An optimized model and test of the China's first high temperature parabolic trough solar receiver
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)
Wind loads on heliostats and parabolic dish collectors: Final subcontractor report
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.
Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish
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)
Water Use in Parabolic Trough Power Plants: Summary Results from WorleyParsons' Analyses
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.
2005 World Oleochemical Conference
This CD-ROM is a compilation of the PowerPoint presentations given at the 2005 World Oleochemical Conference, Meeting Demands of the Future, held 10-13 April 2005, Athens, Greece. 2005 World Oleochemical Conference DVD & CD-ROMs Food Science & Technology
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
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
Research Commentary---Virtual Worlds: A Performative Perspective on Globally Distributed, Immersive Work
Virtual worlds are immersive, simulated, persistent, and dynamic environments that include rich graphical three dimensional spaces, high fidelity audio, motion, viewpoint, and interactivity. Initially dismissed as environments of play, virtual worlds ... Keywords: boundaries, identity, performativity, presence, virtual worlds
Ulrike Schultze; Wanda J. Orlikowski
The World Bank - Transport | Open Energy Information
The World Bank - Transport The World Bank - Transport Jump to: navigation, search Tool Summary LAUNCH TOOL Name: The World Bank - Transport Agency/Company /Organization: The World Bank Focus Area: Governance - Planning - Decision-Making Structure Topics: Analysis Tools Resource Type: Website Website: go.worldbank.org/0SYYVJWB40 This website provides relevant information about transport, focusing on The World Bank Transport Strategy - Safe, Clean and Affordable - Transport for Development. The website includes international publications and toolkits classified by type of transport and/or region/country. How to Use This Tool This tool is most helpful when using these strategies: Avoid - Cut the need for travel Shift - Change to low-carbon modes Improve - Enhance infrastructure & policies
Survey of Thermal Storage for Parabolic Trough Power Plants; Period of Performance: September 13, 1999 - June 12, 2000
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
P-adic Elliptic Quadratic Forms, Parabolic-Type Pseudodifferential Equations With Variable Coefficients, and Markov Processes
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-S�nchez; W. A. Z��iga-Galindo
Eyelid and eyelash detection method in the normalized iris image using the parabolic Hough model and Otsu's thresholding method
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
Study on the Principle and Technology of Coal and Methane Simultaneous Extraction Based on the Mining Fissure Elliptic Parabolic Zone
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
An Efficient Hybrid Parabolic Equation --- Integral Equation Method for the Analysis of Wave Propagation in Highly Complex Indoor Communication Environments
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
World Energy Consumption by Region, 1970-2020
for the developing world. In particular, energy demand in developing Asia (including China, India, and South Korea, but excluding Australia, Japan, and New Zealand) and Central...
Frequency response analysis of fluid control systems for parabolic trough solar collectors
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.
Analytic Q-ball solutions and their stability in a piecewise parabolic potential
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
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: email@example.com, E-mail: firstname.lastname@example.com [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)
Importance of non-parabolic band effects in the thermoelectric properties of semiconductors
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
A 32 m Parabolic Antenna in Peru At 3,370m of Altitude
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
Cleaning strategies for parabolic-trough solar-collector fields; guidelines for decisions
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.
Precise asymptotics for the parabolic Anderson model with a moving catalyst or trap
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
Current and future costs for parabolic trough and power tower systems in the US market.
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
Estimates in Generalized Morrey Spaces for Weak Solutions to Divergence Degenerate Parabolic Systems
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
Mixed finite-difference/integral transform approach for parabolic-hyperbolic problems in transient forced convection
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)
Current and Future Costs for Parabolic Trough and Power Tower Systems in the US Market: Preprint
Turchi, C.; Mehos, M.; Ho, C. K.; Kolb, G. J.
Utility-Scale Parabolic Trough Solar Systems: Performance Acceptance Test Guidelines, April 2009 - December 2010
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.
Experimental and raytrace results for throat-to-throat compound parabolic concentrators
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.
Application of compound parabolic concentrators to solar photovoltaic conversion. Final report
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.
Wind World | Open Energy Information
World Jump to: navigation, search Name Wind World Place Denmark Sector Wind energy Product WindWorld was a turbine manufacturer that was purchased by NEG Micon in 1998. NEG Micon...
World Fossil Fuel Economics - TMS
Jan 1, 1971 ... World Fossil Fuel Economics ... in world energy demand, particularly in the U. S. and Europe; the consumption patterns and cost patterns of oil,�...
Brane World Black Rings
Five dimensional neutral rotating black rings are described from a Randall-Sundrum brane world perspective in the bulk black string framework. To this end we consider a rotating black string extension of a five dimensional black ring into the bulk of a six dimensional Randall-Sundrum brane world with a single four brane. The bulk solution intercepts the four brane in a five dimensional black ring with the usual curvature singularity on the brane. The bulk geodesics restricted to the plane of rotation of the black ring are constructed and their projections on the four brane match with the usual black ring geodesics restricted to the same plane. The asymptotic nature of the bulk geodesics are elucidated with reference to a bulk singularity at the AdS horizon. We further discuss the description of a brane world black ring as a limit of a boosted bulk black 2 brane with periodic identification.
Anurag Sahay; Gautam Sengupta
world | OpenEI
world world Dataset Summary Description Total annual carbon dioxide emissions by country, 2005 to 2009 (million metric tons). Compiled by Energy Information Administration (EIA). Source EIA Date Released Unknown Date Updated Unknown Keywords carbon dioxide emissions EIA world Data text/csv icon total_carbon_dioxide_emissions_from_the_consumption_of_energy_2005_2009million_metric_tons.csv (csv, 12.3 KiB) Quality Metrics Level of Review Peer Reviewed Comment Temporal and Spatial Coverage Frequency Time Period 2005 - 2009 License License Other or unspecified, see optional comment below Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote Ease of access Average vote Your vote Overall rating Average vote Your vote
LCA (Life Cycle Assessment) of Parabolic Trough CSP: Materials Inventory and Embodied GHG Emissions from Two-Tank Indirect and Thermocline Thermal Storage (Presentation)
In the United States, concentrating solar power (CSP) is one of the most promising renewable energy (RE) technologies for reduction of electric sector greenhouse gas (GHG) emissions and for rapid capacity expansion. It is also one of the most price-competitive RE technologies, thanks in large measure to decades of field experience and consistent improvements in design. One of the key design features that makes CSP more attractive than many other RE technologies, like solar photovoltaics and wind, is the potential for including relatively low-cost and efficient thermal energy storage (TES), which can smooth the daily fluctuation of electricity production and extend its duration into the evening peak hours or longer. Because operational environmental burdens are typically small for RE technologies, life cycle assessment (LCA) is recognized as the most appropriate analytical approach for determining their environmental impacts of these technologies, including CSP. An LCA accounts for impacts from all stages in the development, operation, and decommissioning of a CSP plant, including such upstream stages as the extraction of raw materials used in system components, manufacturing of those components, and construction of the plant. The National Renewable Energy Laboratory (NREL) is undertaking an LCA of modern CSP plants, starting with those of parabolic trough design.
Heath, G.; Burkhardt, J.; Turchi, C.; Decker, T.; Kutscher, C.
International Energy Outlook 2000 - World Energy Consumption
The IEO2000 projections indicate continued growth in world energy use, including large increases for the developing economies of Asia and South America. Energy resources are thought to be adequate to support the growth expected through 2020. The IEO2000 projections indicate continued growth in world energy use, including large increases for the developing economies of Asia and South America. Energy resources are thought to be adequate to support the growth expected through 2020. Current Trends Influencing World Energy Demand Changing world events and their effects on world energy markets shape the long-term view of trends in energy demand. Several developments in 1999shifting short-term world oil markets, the recovery of developing Asian markets, and a faster than expected recovery in the economies of the former Soviet Union are reflected in the projections presented in this years International Energy Outlook 2000 (IEO2000). In 1998, oil prices reached 20-year lows as a result of oil surpluses
International Energy Outlook 1999 - World Energy Consumption
world.gif (5615 bytes) world.gif (5615 bytes) The IEO99 projections indicate substantial growth in world energy use,including substantial increases for the developing economies of Asia and South America. Resource availability is not expected to limit the growth of energy markets. In 1998, expectations for economic growth and energy market performance in many areas of the world were dashed. The Asian economic crisis proved to be deeper and more persistent than originally anticipated, and the threat and reality of spillover effects grew through the year. Oil prices crashed. Russias economy collapsed. Economic and social problems intensified in energy- exporting countries and in emerging economies of Asia and South America. Deepening recession in Japan made recovery more difficult in Asia
International Energy Outlook 2001 - World Energy Consumption
World Energy Consumption World Energy Consumption picture of a printer Printer Friendly Version (PDF) This report presents international energy projections through 2020, prepared by the Energy Information Administration, including outlooks for major energy fuels and issues related to electricity, transportation, and the environment. The International Energy Outlook 2001 (IEO2001) presents the Energy Information Administration (EIA) outlook for world energy markets to 2020. Current trends in world energy markets are discussed in this chapter, followed by a presentation of the IEO2001 projections for energy consumption by primary energy source and for carbon emissions by fossil fuel. Uncertainty in the forecast is highlighted by an examination of alternative assumptions about economic growth and their impacts on the
world-class professionals.
World-class facilities 20 Enjoy sports and activities Your studies 24 Study options 28 English Language 30 Faculties 32 Subject areas Essential information 42 How to apply 44 Visa information 46 Fees and teaching facilities - underpinned by a £350million investment programme, and combined with first
World Natural Gas, 1978
World marketed production of natural gas in 1978 totaled 51.749 trillion CF (up from 50.1 TCF in 1977); this 3.3% increase, however, was slightly lower than 1977's 3.7% rise. US production, which fell 0.3% dropped to 38.6% of the world total, while the USSR share (13.137 TCF) accounted for 25.4% (for a growth rate of 7.5%). Of the world gross production of 62.032 TCF, 69.7% came from gas wells; the remainder was associated with oil. Thirty-one percent of the 10.282 TCF difference between gross and marketed gas production was used for oil reservoir repressuring, while the balance (7.094 TCF) was vented and flared. Internationally traded gas movements rose to 11.6% of production. The Netherlands, the USSR, and Canada accounted for 30.6%, 20.1% and 14.7%, respectively, of total 1978 exports. At 0.956 TCF, LNG shipments accounted for 15.9% of world trade, a 35.2% higher share than in 1977; most of this growth was due to increased Indonesia-to-Japan volumes.
World Energy Outlook 2008
U.S. Energy Information Administration (EIA) Indexed Site
OECD/IEA - OECD/IEA - 2008 © OECD/IEA - 2008 © OECD/IEA - 2008 To Cover... To Cover To Cover ... ... Transport Energy and CO 2 Where are we going? What are the dangers? How do we change direction? Primarily reporting on: IEA WEO 2008 IEA ETP 2008 On-going work with IEA's Mobility Model One or two detours to talk about modelling © OECD/IEA - 2008 0 2 000 4 000 6 000 8 000 10 000 12 000 14 000 16 000 18 000 1980 1990 2000 2010 2020 2030 Mtoe Other renewables Hydro Nuclear Biomass Gas Coal Oil World energy demand expands by 45% between now and 2030 - an average rate of increase of 1.6% per year - with coal accounting for more than a third of the overall rise Where are we headed? World Energy Outlook 2008 Where are we headed? World Energy Outlook Where are we headed? World Energy Outlook
Appendix F Cultural Resources, Including
Appendix F Appendix F Cultural Resources, Including Section 106 Consultation STATE OF CALIFORNIA - THE RESOURCES AGENCY EDMUND G. BROWN, JR., Governor OFFICE OF HISTORIC PRESERVATION DEPARTMENT OF PARKS AND RECREATION 1725 23 rd Street, Suite 100 SACRAMENTO, CA 95816-7100 (916) 445-7000 Fax: (916) 445-7053 email@example.com www.ohp.parks.ca.gov June 14, 2011 Reply in Reference To: DOE110407A Angela Colamaria Loan Programs Office Environmental Compliance Division Department of Energy 1000 Independence Ave SW, LP-10 Washington, DC 20585 Re: Topaz Solar Farm, San Luis Obispo County, California Dear Ms. Colamaria: Thank you for seeking my consultation regarding the above noted undertaking. Pursuant to 36 CFR Part 800 (as amended 8-05-04) regulations implementing Section
High concentration two-stage optics for parabolic trough solar collectors with tubular absorber and large rim angle
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))
L{sup p} Theory for Super-Parabolic Backward Stochastic Partial Differential Equations in the Whole Space
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: firstname.lastname@example.com; Qiu, Jinniao, E-mail: email@example.com; Tang Shanjian, E-mail: email@example.com [Fudan University, Department of Finance and Control Sciences, School of Mathematical Sciences, and Laboratory of Mathematics for Nonlinear Sciences (China)
Countries Gasoline Prices Including Taxes
Countries (U.S. dollars per gallon, including taxes) Countries (U.S. dollars per gallon, including taxes) Date Belgium France Germany Italy Netherlands UK US 01/13/14 7.83 7.76 7.90 8.91 8.76 8.11 3.68 01/06/14 8.00 7.78 7.94 8.92 8.74 8.09 3.69 12/30/13 NA NA NA NA NA NA 3.68 12/23/13 NA NA NA NA NA NA 3.63 12/16/13 7.86 7.79 8.05 9.00 8.78 8.08 3.61 12/9/13 7.95 7.81 8.14 8.99 8.80 8.12 3.63 12/2/13 7.91 7.68 8.07 8.85 8.68 8.08 3.64 11/25/13 7.69 7.61 8.07 8.77 8.63 7.97 3.65 11/18/13 7.99 7.54 8.00 8.70 8.57 7.92 3.57 11/11/13 7.63 7.44 7.79 8.63 8.46 7.85 3.55 11/4/13 7.70 7.51 7.98 8.70 8.59 7.86 3.61 10/28/13 8.02 7.74 8.08 8.96 8.79 8.04 3.64 10/21/13 7.91 7.71 8.11 8.94 8.80 8.05 3.70 10/14/13 7.88 7.62 8.05 8.87 8.74 7.97 3.69
Solid-state laser pumping with a planar compound parabolic concentrator
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)
Development of Performance Acceptance Test Guidelines for Large Commercial Parabolic Trough Solar Fields: Preprint
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.
Side-by-side comparisons of evacuated compound parabolic concentrator and flat plate solar collector systems
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.
An off-axis Cassegrain optimal design for short focal length parabolic solar concentrators
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
Charcoal-methanol adsorption refrigerator powered by a compound parabolic concentrating solar collector
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))
Summary World Biofuels Energy Data (from World on the Edge) ...
related to world biofuels production. It is part of a supporting dataset for the book World On the Edge: How to Prevent Environmental and Economic Collapse by�Lester R....
World Oil Refining Logistics Demand Model "World" Reference Manual
Reports and Publications (EIA)
This manual is intended primarily for use as a reference by analysts applying the WORLD model to regional studies. It also provides overview information on WORLD features of potential interest to managers and analysts.
Information Center
World Energy Projection System Plus Model Documentation: World Electricity Model
This report documents the objectives, analytical approach and development of the World Energy Projection System Plus (WEPS+) World Electricity Model. It also catalogues and describes critical assumptions, computational methodology, parameter estimation techniques, and model source code.
International Energy Outlook - World Energy and Economic Outlook
World Energy and Economic Outlook World Energy and Economic Outlook International Energy Outlook 2004 World Energy and Economic Outlook The IEO2004 projections indicate continued growth in world energy use, including large increases for the developing economies of Asia. Energy resources are thought to be adequate to support the growth expected through 2025. Figure 12. World Primary Energy Consumption, 1970-2025. Need help, call the National Energy Information Center at 202-586-8800 Figure Data Figure 13. World Energy Consumption by Region, 1970-2025. Need help, call the National Energy Information Center at 202-586-8800. Figure Data Figure 14. World Primary Energy Consumption by Energy Source, 1970-2025. Need help, call the National Energy Information Center at 202-586-8800. Figure Data
Mexico-World Bank Climate Projects | Open Energy Information
World Bank Climate Projects World Bank Climate Projects Agency/Company /Organization World Bank Sector Energy Focus Area Energy Efficiency, Renewable Energy, Transportation Topics Market analysis, Background analysis Resource Type Dataset Country Mexico Central America References World Bank Project Database - Mexico [1] Contents 1 Active World Bank climate projects in Mexico including 1.1 Urban Transport Transformation 1.2 Efficient Lighting and Appliances 1.3 Sustainable Transport and Air Quality 1.4 Sustainable Rural - IBRD 1.5 Sustainable Rural Development - GEF 1.6 Mexico Framework for Green Growth Development Policy Loan 1.7 Mexico Environmental Sustainability Development Policy Loan 2 References Active World Bank climate projects in Mexico including Urban Transport Transformation (180M Pipeline)
A World Wide Web Update
A World Wide Web Update The Center for Building Science now has a World Wide Web homepage accessible from the general LBL homepage. Through WWW and the Mosaic browser, Internet...
Our World Argonne's
At Argonne National Laboratory, we passionately pursue At Argonne National Laboratory, we passionately pursue energy-efficient technologies and renewable energy innovations that contribute to a better, cleaner future for all. Energy to Renew Our World Argonne's Research in Energy Efficiency and Renewable Energy As we begin our journey into the 21st century, the U.S. Department of Energy's (DOE) Argonne National Laboratory continues to make significant contributions to the nation's health and well being by delivering achievements in energy technology development and deployment. We are working toward technological
World Bank Group
purpose of this Good Practice Note is to increase the awareness of the health risks related to occupational asbestos exposure, provide a list of resources on international good practices available to minimize these risks, and present an overview of some of the available product alternatives on the market. The need to address asbestos-containing materials (ACM) as a hazard is no longer under debate but a widely accepted fact. Practices regarding asbestos that are normally considered acceptable by the World Bank Group (WBG) in projects supported through its lending or other instruments are addressed in the WBG�s General Environmental, Health and Safety (EHS) Guidelines. 1 This Good Practice Note provide background and context for the guidance in the WBG EHS Guidelines. Good practice is to minimize the health risks associated with ACM by avoiding their use in new construction and renovation, and, if installed asbestos-containing materials are encountered, by using internationally recognized standards and best practices (such as those presented in Appendix 3) to mitigate their impact. In all cases, the Bank expects borrowers and other clients of World Bank funding to use alternative materials wherever feasible.
unknown authors
World Biofuels Study
This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very rapidly over the next two decades, provided policymakers stay the course with their policy goals. This project relied on a scenario-based analysis to study global biofuel markets. Scenarios were designed to evaluate the impact of different policy proposals and market conditions. World biofuel supply for selected scenarios is shown in Figure 1. The reference case total biofuel production increases from 12 billion gallons of ethanol equivalent in 2005 to 54 billion gallons in 2020 and 83 billion gallons in 2030. The scenarios analyzed show volumes ranging from 46 to 64 billion gallons in 2020, and from about 72 to about 100 billion gallons in 2030. The highest production worldwide occurs in the scenario with high feedstock availability combined with high oil prices and more rapid improvements in cellulosic biofuel conversion technologies. The lowest global production is found in the scenario with low feedstock availability, low oil prices and slower technology progress.
Participation in multilateral effort to develop high performance integrated CPC evacuated collectors. [Compound Parabolic Concentrator (CPC)
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.
Investing in sustainability at Coral World
Now open and operational for several years, Coral World offers a unique environmental model for other tourism-related facilities throughout the Caribbean and beyond. The extensive energy conservation program has yielded a 40 to 50% reduction in energy use and costs. The facility's unique on-site storm water absorption system virtually eliminates silt runoff to the coastal waters. The innovative, highly cost-effective series of renewable energy installations include a photovoltaic-powered restaurant kitchen, solar hot water systems and one of the world's first hydroelectric systems that uses wastewater drainage for turbine source waters. The extensive marine environmental conservation program protects fragile local ecosystems while also protecting the owners' investment in tourism. By investing aggressively in sustainability, Coral World's owners are reaping the benefits not only in reduced operating costs and improved profitability, but also in increased visitor volume and satisfaction.
Jackson, O.
NETL: 2010 World Gasification Database Archive
Home > Technologies > Coal & Power Systems > Gasification Systems > 2010 World Gasification Database Home > Technologies > Coal & Power Systems > Gasification Systems > 2010 World Gasification Database Gasification Systems 2010 Worldwide Gasification Database Archive DOE/NETL 2010 Worldwide Gasification Database Worldwide Gasification Database Analysis The 2010 Worldwide Gasification Database describes the current world gasification industry and identifies near-term planned capacity additions. The database lists gasification projects and includes information (e.g., plant location, number and type of gasifiers, syngas capacity, feedstock, and products). The database reveals that the worldwide gasification capacity has continued to grow for the past several decades and is now at 70,817 megawatts thermal (MWth) of syngas output at 144 operating plants with a total of 412 gasifiers.
Dedicated to making the world safer by providing better security
Dedicated to making the world safer by providing better security to nuclear materials during transportation worldwide "Nuclear material around the world must be made more physically secure to make certain)946-1507 Email: email@example.com Experience includes · Providing comprehensive security solutions to nuclear
Gravity on a Dilatonic Gauss-Bonnet Brane World
The effective four-dimensional, linearised gravity of a Randall-Sundrum-like brane world model is analysed. The model includes higher order curvature terms (such as the Gauss-Bonnet term) and a scalar field. The resulting brane worlds can have better agreement with observations than the equivalent Einstein gravity models.
Stephen C. Davis
World nuclear outlook 1995
As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.
World nuclear outlook 1994
As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2010 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for three different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.
Oils and Fats World Market Update 2011
Archive of the Oils and Fats World Market Update 2011 Oils and Fats World Market Update 2011 Izmir, Turkey Oils and Fats World Market Update 2011 ...
Oils and Fats World Market Update 2013
Archive of AOCS Oils and Fats World Market Update 2013 Oils and Fats World Market Update 2013 Kiev, Ukraine Oils and Fats World Market Update 2013 ...
6th World Conference on Detergents
Archive of 6th World Conference on Detergents. 6th World Conference on Detergents Montreux , Switzerland 6th World Conference on Detergents ...
Department of Energy Finalizes Loan Guarantee to Support World...
million homes. Additional DOE-supported projects include two of the world's largest solar thermal projects and a 2,200 megawatt nuclear power plant - the nation's first in three...
the World Wide Web
Office of Scientific and Technical Information (OSTI)
technical report has been made technical report has been made electronically available on the World Wide Web through a contribution from Walter L. Warnick In honor of Enrico Fermi Leader of the first nuclear reactor, Nobel Prize winner, and visionary technologist Dr. Warnick is delighted to be the first sponsor for posting a Department of Energy technical report and making it broadly available Office of Scientific and Technical Information Office of Science U.S. Department of Energy September 2008 osti.gov U N I T E D S T A T E S A T O M I C E N E R G Y C O M M I S S I O N AECD-3269 EXPERIMENTAL PRODUCTION OF A DNERGENT CHAIN REACTION BY E. Fermi January 4, 1952 [TIS Issuance ate] [chicago University] - T e c h n i c a l I n f o r m a t i o n S e r v i c e , O a k Ridge, T e n n e s s e e r ABSTRACTS Description of the construction and operation of the chain
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
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.
World Trade Center Investigation Status
... Approximately half (51%) of WTC occupants had never used a stairwell at the World Trade Center prior to ... fine, the electricity was fine�� (70's) ...
Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish: I-test and analysis
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))
Gamma bang time/reaction history diagnostics for the National Ignition Facility using 90 deg. off-axis parabolic mirrors
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)
Los Alamos supercomputer remains fastest in world
world Los Alamos supercomputer remains fastest in world The latest list of the TOP500 computers in the world continued to place the Roadrunner supercomputer as fastest in the world...
The World Energy Projection System
World Energy Projection System World Energy Projection System May 1998 Continuing with this release, annual updates to the model will be available. Check this space for scheduled future releases. Note: If you are familiar with the model and just wish to download the latest version, click HERE. The World Energy Projection System The projections of world energy consumption published annually by the Energy Information Administration (EIA) in the International Energy Outlook (IEO) are derived from the World Energy Projection System (WEPS). WEPS is an integrated set of personal computer-based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the
Science Accelerator content now includes multimedia
Science Accelerator content now includes multimedia Science Accelerator has expanded its suite of collections to include ScienceCinema, which contains videos produced by the U.S....
EIA model documentation: World oil refining logistics demand model,``WORLD`` reference manual. Version 1.1
This manual is intended primarily for use as a reference by analysts applying the WORLD model to regional studies. It also provides overview information on WORLD features of potential interest to managers and analysts. Broadly, the manual covers WORLD model features in progressively increasing detail. Section 2 provides an overview of the WORLD model, how it has evolved, what its design goals are, what it produces, and where it can be taken with further enhancements. Section 3 reviews model management covering data sources, managing over-optimization, calibration and seasonality, check-points for case construction and common errors. Section 4 describes in detail the WORLD system, including: data and program systems in overview; details of mainframe and PC program control and files;model generation, size management, debugging and error analysis; use with different optimizers; and reporting and results analysis. Section 5 provides a detailed description of every WORLD model data table, covering model controls, case and technology data. Section 6 goes into the details of WORLD matrix structure. It provides an overview, describes how regional definitions are controlled and defines the naming conventions for-all model rows, columns, right-hand sides, and bounds. It also includes a discussion of the formulation of product blending and specifications in WORLD. Several Appendices supplement the main sections.
Probability of passing through a parabolic barrier and thermal decay rate: Case of linear coupling both in momentum and in coordinate
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)
Summary World Oil Data (from World on the Edge)
Oil Data (from World on the Edge) This dataset presents summary...
Petroleum Gasoline & Distillate Needs Including the Energy ...
U.S. Energy Information Administration (EIA)
Petroleum Gasoline & Distillate Needs Including the Energy Independence and Security Act (EISA) Impacts
Home > Petroleum > Analysis > Petroleum Gasoline & Distillate Needs Including the Energy Independence and Security Act (EISA) ...
Anthropometry for WorldSID, a World-Harmonized Midsize Male Side Impact Crash Dummy
The WorldSID project is a global effort to design a new generation side impact crash test dummy under the direction of the International Organization for Standardization (ISO). The first WorldSID crash dummy will represent a world-harmonized mid-size adult male. This paper discusses the research and rationale undertaken to define the anthropometry of a world standard midsize male in the typical automotive seated posture. Various anthropometry databases are compared region by region and in terms of the key dimensions needed for crash dummy design. The Anthropometry for Motor Vehicle Occupants (AMVO) dataset, as established by the University of Michigan Transportation Research Institute (UMTRI), is selected as the basis for the WorldSID mid-size male, updated to include revisions to the pelvis bone location. The proposed mass of the dummy is 77.3kg with full arms. The rationale for the selected mass is discussed. The joint location and surface landmark database is appended to this paper.
S. Moss; Z. Wang; M. Salloum; M. Reed; M. Van Ratingen; D. Cesari; R. Scherer; T. Uchimura; M. Beusenberg
BP Statistical Review of World Energy | Open Energy Information
Review of World Energy Review of World Energy Jump to: navigation, search Name BP Statistical Review of World Energy Data Format Excel Spreadsheet Geographic Scope Earth TODO: Import actual dataset contents into OpenEI The BP Statistical Review of World Energy is an Excel spreadsheet which contains consumption and production data for Coal, Natural Gas, Nuclear, Oil, and Hydroelectric energy. It is produced annually by British Petroleum.[1] Data from the BP Statistical Review is used in various tools, including the Energy Export Databrowser.[1] External links 2009 Data 2008 Data 2007 Data 2006 Data 2005 Data 2004 Data 2003 Data 2002 Data References ↑ 1.0 1.1 "Sources of data used in the Energy Export Databrowser" Retrieved from "http://en.openei.org/w/index.php?title=BP_Statistical_Review_of_World_Energy&oldid=272979"
World Bank-Climate Change Knowledge Portal | Open Energy Information
Portal Portal Jump to: navigation, search Logo: World Bank-Climate Change Knowledge Portal Name World Bank-Climate Change Knowledge Portal Agency/Company /Organization World Bank Sector Climate Resource Type Maps, Training materials, Lessons learned/best practices Website http://sdwebx.worldbank.org/cl References World Bank-Climate Change Knowledge Portal[1] Abstract The WB Climate Change Portal is intended to provide quick and readily accessible climate and climate-related data to policy makers and development practitioners. World Bank-Climate Change Knowledge Portal Screenshot "The WB Climate Change Portal is intended to provide quick and readily accessible climate and climate-related data to policy makers and development practitioners. The site also includes a mapping visualization tool (webGIS) that displays
Hysteresis and re-entrant melting of a self-organized system of classical particles confined in a parabolic trap
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
A Gas Dynamics Method Based on The Spectral Deferred Corrections (SDC) Time Integration Technique and The Piecewise Parabolic Method (PPM)
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
Group velocity dispersion and relativistic effects on the wakefield induced by chirped laser pulse in parabolic plasma channel
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)
Effect of variation of angle of inclination on the performance of low-concentration-ratio compound parabolic concentrating solar collectors
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)
Travel Notes - World Market Update
Travel notes, air travel, rail travel. Travel Notes - World Market Update Biofuels and Bioproducts and Biodiesel Processing Elearning Olive oil Industry Events Industrial Oil Products Abstracts Program Travel Hotel Short Courses Exhibits Regi
The world price of coal
A significant increase in the seaborne trade for coal over the past twenty years has unified formerly separate coal markets into a world market in which prices move in tandem. Due to its large domestic market, the United ...
Ellerman, A. Denny
Hewlett and Anderson- New World
Energy.gov (U.S. Department of Energy (DOE))
Richard G. Hewlett and Oscar E. Anderson, Jr. The New World, 1939-1946. Volume I: A History of the Atomic Energy Commission. 1962. Text in each PDF is fully searchable.
Wartime Figures (World War II)
3. Before joining the Manhattan Project, Enrico Fermi built the world's first nuclear reactor, and had already won a Nobel Prize in part for his discovery of new elements. At Los...
World Year of Physics 2005
IMAGE: World Year of Physics 2005 nameplate Berkeley Lab logo Berkeley Lab Celebrates World Year of Physics 2005 Berkeley Lab Web Search Berkeley Lab Phone Book Berkeley Lab A-Z Index Berkeley Lab Privacy and Security Notice IMAGE: World Year of Physics 2005 nameplate Berkeley Lab logo Berkeley Lab Celebrates World Year of Physics 2005 Berkeley Lab Web Search Berkeley Lab Phone Book Berkeley Lab A-Z Index Berkeley Lab Privacy and Security Notice IMAGE: World of Physics graphic Symposia page link Special Events page link Lectures page link Education page link The World Year of Physics is a worldwide celebration of physics and its importance in our everyday lives. Physics not only plays an important role in the development of science and technology but also has a tremendous impact on our society. WYP aims to raise the worldwide awareness of physics and physical science. The United Nations has declared 2005 to be the International Year of Physics. This declaration coincides with the 100th anniversary of physicist
World coal outlook to the year 2000
The 1983 edition of the World Coal Outlook to the Year 2000 examines the worldwide impact of lower oil prices and lower economic activity on the demand, production, and international trade in coal. The report includes detailed regional forecasts of coal demand by end-use application. Regions include the US, Canada, Western Europe, Japan, Other Asia, Latin America, Africa, Australia/New Zealand, Communist Europe, and Communist Asia. In addition, regional coal production forecasts are provided with a detailed analysis of regional coal trade patterns. In all instances, the changes relative to Chase's previous forecasts are shown. Because of the current situation in the oil market, the report includes an analysis of the competitive position of coal relative to oil in the generation of electricity, and in industrial steam applications. The report concludes with an examination of the impact of an oil price collapse on the international markets for coal.
Energy efficient buildings: A world of possibilities
Throughout the world, buildings are a major energy consumer. However, it can be shown that buildings that save from 30 to 50% over common practice can be built using available technologies while actually increasing occupant comfort and functionality. In addition, many technologies are in the development stage that promise even further increases in energy efficiency in buildings. This paper reviews the current state-of-the-art in energy efficient building practice including building equipment and envelopes. Topics discussed include heating, ventilating and air conditioning equipment; lighting; insulation; building envelopes; and building commissioning. The energy effects of switching to non-chlorofluorocarbons in building insulation and refrigeration equipment are discussed. Advanced technologies currently under development that might have a substantial impact on future energy use including advanced absorption chillers, new lighting and window technologies, and thermally activated heat pumps are also described. 24 refs., 6 figs.
Kuliasha, M.A.
SolarWorld Korea | Open Energy Information
SolarWorld Korea Jump to: navigation, search Name SolarWorld Korea Place Korea (Republic) Sector Solar Product Korea-based JV set up by SolarWorld AG and SolarPark Engineering Co...
ClearWorld Now | Open Energy Information
ClearWorld Now Jump to: navigation, search Name ClearWorld Now Place Beijing, China Zip 100027 Product China-based operational investment arm of ClearWorld Energy Ltd. References...
World energy: Building a sustainable future
As the 20th century draws to a close, both individual countries and the world community face challenging problems related to the supply and use energy. These include local and regional environmental impacts, the prospect of global climate and sea level change associated with the greenhouse effect, and threats to international relations in connection with oil supply or nuclear proliferation. For developing countries, the financial cost of providing energy to provide basic needs and fuel economic development pose an additional burden. To assess the magnitude of future problems and the potential effectiveness of response strategies, it is important to understand how and why energy use has changed in the post and where it is heading. This requires study of the activities for which energy is used, and of how people and technology interact to provide the energy services that are desired. The authors and their colleagues have analyzed trends in energy use by sector for most of the world`s major energy-consuming countries. The approach we use considers three key elements in each sector: the level of activity, structural change, and energy intensity, which expresses the amount of energy used for various activities. At a disaggregated level, energy intensity is indicative of energy efficiency. But other factors besides technical efficiency also shape intensity.
Schipper, L.; Meyers, S.
World Class Boilers and Steam Distribution System
�World class� is a term used to describe steam systems that rank in the top 20% of their industry based on quantitative system performance data and energy management for the facility. The rating is determined through a proceduralized assessment process that includes technical features such as boiler efficiency and the percentage of failed steam traps. Management features such as the internal metrices and adequate staffing and training area also included in the assessment. These results are compared with benchmarks for the subject industry. Chemical plants are compared with other chemical plants instead of aggregated data from refining, food processing, health care, etc. This approach provides relevant comparisons and realistic performance targets. The assessment process and industry benchmarks have been developed through sources that include those in the public domain and proprietary industry data. Periodic review and updates are used to ensure that the data accurately represents the relevant industrial profile. Some companies may question why they should upgrade their system. The most obvious answer will be found in the benefits that derive from more efficient operations. Costs are reduced, reliability is improved, and adverse environmental impacts are mitigated. Successful upgrading and maintenance of the energy system requires management support. This may necessitate changes in current practices, technical upgrades to equipment, additional personnel, or other resources. Managers must communicate the message that they want energy management at their plant to be world class.
Portell, V. P.
Sustainable World Capital | Open Energy Information
"Sustainable World Capital" Retrieved from "http:en.openei.orgwindex.php?titleSustainableWorldCapital&oldid351925" Categories: Clean Energy Organizations Companies...
wepstitle.gif (8166 bytes) wepstitle.gif (8166 bytes) Continuing with this release, annual updates to the model will be available. Check this space for scheduled future releases. Note: If you are familiar with the model and just wish to download the latest version, click HERE. The World Energy Projection System The projections of world energy consumption published annually by the Energy Information Administration (EIA) in the International Energy Outlook (IEO) are derived from the World Energy Projection System (WEPS). WEPS is an integrated set of personal computer-based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the
Continuing with this release, annual updates to the model will be Continuing with this release, annual updates to the model will be available. Check this space for scheduled future releases. Note: If you are familiar with the model and just wish to download the latest version, click HERE. The World Energy Projection System The projections of world energy consumption published annually by the Energy Information Administration (EIA) in the International Energy Outlook (IEO) are derived from the World Energy Projection System (WEPS). WEPS is an integrated set of personal computer-based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the
World`s LPG supply picture will change by 2000
Middle East LPG producers will continue to dominate world export markets in 1996. Led by Saudi Arabia, the Middle East will produce nearly 26 million metric tons of LPG in million metric tons of LPG in 1996, more than 54% of the world`s almost 48 million metric tons of export LPG. In 2000, however, with world exports of LPG expanding to 58.9 million metric tons, Middle East suppliers; share will have remained flat, making up 31.7 million metric tons, or 53.9%. Saudi Arabia`s contribution will exceed 15 million metric tons, reflecting essentially no growth since 1995. These and other patterns, from data compiled by Purvin and Gertz, Dallas, and published earlier this year, show other suppliers of LPG, especially African (Algeria/Nigeria), North Sea, and Latin American (Venezuela/Argentina), picking up larger shares in the last 5 years of this decade. This scenario assumes completion of several major supply projects that are either panned, under construction, or nearing start up in most of these areas. The paper discusses the global picture, the supply situation in the Middle East, Africa, the North Sea, and South America.
True, W.R.
World oil: Market or mayhem
The world oil market is regarded by many as a puzzle. Why are oil prices so volatile? What is OPEC and what does OPEC do? Where are oil prices headed in the long run? Is �peak oil � a genuine concern? Why did oil prices spike in the summer of 2008, and what role did speculators play? Any attempt to answer these questions must be informed and disciplined by economics. Such is the purpose of this essay: to illuminate recent developments in the world oil market from the perspective of economic theory.
James L. Smith; James L. Smith; Larry Debrock; Dwight Lee; John Parsons
Solar World USA not SolarWorld AG | Open Energy Information
World USA not SolarWorld AG World USA not SolarWorld AG Jump to: navigation, search Name Solar World USA (not SolarWorld AG) Place Colorado Springs, Colorado Zip 80907 Sector Solar Product Solar World manufactures solar powered products for educational, consumer, electronic and custom OEM markets. References Solar World USA (not SolarWorld AG)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Solar World USA (not SolarWorld AG) is a company located in Colorado Springs, Colorado . References ↑ "Solar World USA (not SolarWorld AG)" Retrieved from "http://en.openei.org/w/index.php?title=Solar_World_USA_not_SolarWorld_AG&oldid=351350" Categories: Clean Energy Organizations
Imagine a list of American innovations that would convey some sense of our nation's distinctiveness in the world. Depending on
's distinctiveness in the world. Depending on the list-maker's mood, it might include the atom bomb, jazz the week U.S. News & World Report comes out with its annual college rankings IntroductIon Copyrighted
Landweber, Laura
Design and analysis of hydraulically driven actuation system For a parabolic solar trough.
??Cataloged from PDF version of thesis.Includes bibliographical references (page 34).This thesis documents Katarina Popovic's contribution to the design of hydraulic cylinder actuation system for day� (more)
Popovi?, Katarina, S.B. Massachusetts Institute of Technology
Mechanical development of an actuation system for a parabolic solar trough collector.
??Cataloged from PDF version of thesis.Includes bibliographical references (page 26).This thesis documents my personal contribution to the development of a hydraulic-based actuation system for a� (more)
Carrillo, Juan Felipe (Carrillo Salazar)
Parabolic versus elliptic focusing - Optimization of the focusing design of a cold triple-axis neutron spectrometer by Monte-Carlo simulations
We present Monte-Carlo simulations for the focusing design of a novel cold-neutron triple-axis spectrometer to be installed at the end position of the cold guide NL-1 of the research reactor FRM-II in Munich, Germany. Our simulations are of general relevance for the design of triple-axis spectrometers at end positions of neutron guides. Using the McStas program code we performed ray trajectories to compare parabolic and elliptic focusing concepts. In addition the design of the monochromator was optimized concerning crystal size and mosaic spread. The parabolic focusing concept is superior to the elliptic alternative in view of the neutron intensity distribution as a function of energy and divergence. In particular, the elliptical configuration leads to an inhomogeneous divergence distribution.
Komarek, A C; Braden, M
Secretary Chu Joins with World Leaders to Sign International Partnership
Joins with World Leaders to Sign International Joins with World Leaders to Sign International Partnership for Energy Efficiency Cooperation Secretary Chu Joins with World Leaders to Sign International Partnership for Energy Efficiency Cooperation May 24, 2009 - 12:00am Addthis The Department of Energy announced today that U.S. Energy Secretary Steven Chu joined with top energy leaders from around the world to launch the International Partnership for Energy Efficiency Cooperation (IPEEC). As part of the Group of 8 (G8) Energy Ministers Meeting in Rome this weekend, G8 members and other interested countries took steps to accelerate the implementation of energy efficient measures in their economies. IPEEC signatories included members of the G8 - Canada, France, Germany, Italy, Japan, the Russian Federation, the United Kingdom, and the United States,
Achieving world class maintenance status
The article written by a management consultant, discusses the art of successful planning and operation of maintenance in mines considering factors such as benchmaking, key performance indices (KPIs) and frequency of procedures which can help achieve 'world class maintenance'. 1 fig.
Tomlingson, P.D. [Paul D. Tomingson Associates (United States)
World Oil: Market or Mayhem?
The world oil market is regarded by many as a puzzle. Why are oil prices so volatile? What is OPEC and what does OPEC do? Where are oil prices headed in the long run? Is �peak oil� a genuine concern? Why did oil prices ...
Smith, James L.
1974 FORESTER the world a
1974 FORESTER #12;#12;2 TREES make the world a better place in which to live! #12;TABLE OF CONTENTS . .... . .... . . . . . .....63 ADVERTISERS . . .. . . . . . .. ....... ....... .. 75 #12;FORESTER'S SALUTE TO DR. ERIC A. BOUROO. The Forester salutes Dean Bourdo for his accomplishments in advancing forestry at Michigan Tech, as a member
World Conference on Oilseed Processing
Fats and Oils Industry Professionals Gather in Izmir, Turkey Industry professionals will review and discuss the day-to-day concerns and critical issues related to soyabean, sunflower, corn, canola, olive and palm, and other tropical oils at the World Con
UCL MEDICAL SCHOOL world class
UCL MEDICAL SCHOOL world class medicine in the heart of London Guide for prospective students 2012/2013 #12;Vice Provost (Health), Head of UCL School of Life and Medical Sciences and Head of UCL Medical School Professor Sir John Tooke Vice Dean, Director of Medical Education and the Division of Medical
Saunders, Mark
MicrobeWorld Radio and Communications Initiative
MicrobeWorld is a 90-second feature broadcast daily on more than 90 public radio stations and available from several sources as a podcast, including www.microbeworld.org. The feature has a strong focus on the use and adapatbility of microbes as alternative sources of energy, in bioremediation, their role in climate, and especially the many benefits and scientific advances that have resulting from decoding microbial genomes. These audio features are permanantly archived on an educational outreach site, microbeworld.org, where they are linked to the National Science Education Standards. They are also being used by instructors at all levels to introduce students to the multiple roles and potential of microbes, including a pilot curriculum program for middle-school students in New York.
Barbara Hyde
Gas storage materials, including hydrogen storage materials
A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.
Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji
Solar multiple optimization for a solar-only thermal power plant, using oil as heat transfer fluid in the parabolic trough collectors
Usual size of parabolic trough solar thermal plants being built at present is approximately 50 MW{sub e}. Most of these plants do not have a thermal storage system for maintaining the power block performance at nominal conditions during long non-insolation periods. Because of that, a proper solar field size, with respect to the electric nominal power, is a fundamental choice. A too large field will be partially useless under high solar irradiance values whereas a small field will mainly make the power block to work at part-load conditions. This paper presents an economic optimization of the solar multiple for a solar-only parabolic trough plant, using neither hybridization nor thermal storage. Five parabolic trough plants have been considered, with the same parameters in the power block but different solar field sizes. Thermal performance for each solar power plant has been featured, both at nominal and part-load conditions. This characterization has been applied to perform a simulation in order to calculate the annual electricity produced by each of these plants. Once annual electric energy generation is known, levelized cost of energy (LCOE) for each plant is calculated, yielding a minimum LCOE value for a certain solar multiple value within the range considered. (author)
Montes, M.J. [E.T.S.I.Industriales - U.N.E.D., C/Juan del Rosal, 12, 28040 Madrid (Spain); Abanades, A.; Martinez-Val, J.M.; Valdes, M. [E.T.S.I.Industriales - U.P.M., C/Jose Gutierrez Abascal, 2, 28006 Madrid (Spain)
Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss
The thermal efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The thermal efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain the thermal efficiency curve. This paper describes this approach and also makes the case that there are advantages to plotting collector efficiency versus the difference between the operating temperature and the ambient temperature at which the receiver heat loss was measured divided by radiation to a fractional power (on the order of 1/3 but obtained via data regression) - as opposed to the difference between operating and ambient temperatures divided by the radiation. The results are shown to be robust over wide ranges of ambient temperature, sky temperature, and wind speed.
Kutscher, C.; Burkholder, F.; Stynes, J. K.
Life Cycle Assessment of a Parabolic Trough Concentrating Solar Power Plant and Impacts of Key Design Alternatives: Preprint
Climate change and water scarcity are important issues for today's power sector. To inform capacity expansion decisions, hybrid life cycle assessment is used to evaluate a reference design of a parabolic trough concentrating solar power (CSP) facility located in Daggett, California, along four sustainability metrics: life cycle greenhouse gas (GHG) emissions, water consumption, cumulative energy demand (CED), and energy payback time (EPBT). This wet-cooled, 103 MW plant utilizes mined nitrate salts in its two-tank, thermal energy storage (TES) system. Design alternatives of dry-cooling, a thermocline TES, and synthetically-derived nitrate salt are evaluated. During its life cycle, the reference CSP plant is estimated to emit 26 g CO2eq per kWh, consume 4.7 L/kWh of water, and demand 0.40 MJeq/kWh of energy, resulting in an EPBT of approximately 1 year. The dry-cooled alternative is estimated to reduce life cycle water consumption by 77% but increase life cycle GHG emissions and CED by 8%. Synthetic nitrate salts may increase life cycle GHG emissions by 52% compared to mined. Switching from two-tank to thermocline TES configuration reduces life cycle GHG emissions, most significantly for plants using synthetically-derived nitrate salts. CSP can significantly reduce GHG emissions compared to fossil-fueled generation; however, dry-cooling may be required in many locations to minimize water consumption.
Heath, G. A.; Burkhardt, J. J.; Turchi, C. S.
Goals study for technical development and economic evaluation of the compound parabolic concentrator concept for solar energy collector applications
The Argonne National Laboratories, contracted with Arthur D. Little, Inc. (ADL), to perform a 6 week goal study for the purpose of evaluating the technical applicability and the economic viability of the compound parabolic concentrator (CPC) concept for all solar energy applications except large central power plants. During this period, we studied the use of CPC units in a large number of residential, industrial, and commercial applications. The predicted performance of CPC augmented solar collectors was compared with other available solar collectors. Application of the CPC to on-site power generation using solar Rankine power generation techniques was studied in detail. Techniques and costs for fabricating CPC collectors were studied. Collectors with insulation and with full-surface reflectors were studied along with the use of CPC augmentation for evacuated receivers with selective surfaces. Manufacturing costs are compared with those reported by others. A qualitative comparison was made between the various classes of solar collectors that are either presently available or are expected to become available in the near future. Comparative energy costs for various collectors are discussed based upon the predicted performance and the estimated costs for manufacture. The problems of introducing the CPC, or other advanced technology type of solar collectors, into the U. S. construction and HVAC market are briefly discussed. (auth)
Intentionally Including - Engaging Minorities in Physics Careers |
Intentionally Including - Engaging Minorities in Physics Careers Intentionally Including - Engaging Minorities in Physics Careers Intentionally Including - Engaging Minorities in Physics Careers April 24, 2013 - 4:37pm Addthis Joining Director Dot Harris (second from left) were Marlene Kaplan, the Deputy Director of Education and director of EPP, National Oceanic and Atmospheric Administration, Claudia Rankins, a Program Officer with the National Science Foundation and Jim Stith, the past Vice-President of the American Institute of Physics Resources. Joining Director Dot Harris (second from left) were Marlene Kaplan, the Deputy Director of Education and director of EPP, National Oceanic and Atmospheric Administration, Claudia Rankins, a Program Officer with the National Science Foundation and Jim Stith, the past Vice-President of the
Transmission line including support means with barriers
A gas insulated transmission line includes an elongated outer sheath, a plurality of inner conductors disposed within and extending along the outer sheath, and an insulating gas which electrically insulates the inner conductors from the outer sheath. A support insulator insulatably supports the inner conductors within the outer sheath, with the support insulator comprising a main body portion including a plurality of legs extending to the outer sheath, and barrier portions which extend between the legs. The barrier portions have openings therein adjacent the main body portion through which the inner conductors extend.
Cookson, Alan H. (Pittsburgh, PA)
Clean Cities Around the World
This fact sheet provides an update of Clean Cities International news, including successful activities, notable accomplishments, and plans for the future. It also includes background information.
THE WORLD'S Biggest Fan Collection
WORLD'S Biggest Fan Collection WORLD'S Biggest Fan Collection If you only know the Big Ass Fan Company as the preeminent designer and manufacturer of high volume, low speed fans for factories and cows, it's time you get to know us better. While we continue to lead the way in industrial and agricultural air movement, we've also refined these designs to bring the same innovation and benefits of our famous fans to circulate an ocean of air in sound-sensitive commercial spaces and homes. And when our customers said they wanted something for smaller spaces, we listened - and we think you'll like the results. We've got you covered - ceiling to floor, wall to door! Features New patented airfoil system uses 10 Powerfoil airfoils, winglets and patent-pending AirFence(tm) technology to increase
Long Term World Oil Supply
0 0 Notes: The following pages summarize a recent EIA presentation on estimates of the world conventional oil resource base and the year when production from it will peak and then begin to decline. A version of this presentation was given by former EIA Administrator Jay Hakes to the April 18, 2000 meeting of the American Association of Petroleum Geologists in New Orleans, Louisiana. Specific information about this presentation may be obtained from John Wood (email@example.com), Gary Long (firstname.lastname@example.com) or David Morehouse (firstname.lastname@example.com). Long Term World Oil Supply http://www.eia.doe.gov/pub/oil_gas/petroleum/presentations/2000/long_term_supply/sld001.htm [8/10/2000 4:56:23 PM] Slide 2 of 20 http://www.eia.doe.gov/pub/oil_gas/petroleum/presentations/2000/long_term_supply/sld002.htm [8/10/2000 4:56:24 PM]
World Bank | Open Energy Information
Bank Bank Jump to: navigation, search Logo: World Bank Name World Bank Address 1818 H Street, NW Place Washington, District of Columbia Zip 20433 Number of employees 10,000+"+" is not declared as a valid unit of measurement for this property. Year founded 1944 Phone number (202) 473-1000 Coordinates 38.899458°, -77.042447° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.899458,"lon":-77.042447,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
DISASTER POLICY Including Extreme Emergent Situations (EES)
on the ACGME website with information relating to the ACGME response to the disaster. 3. The University-specific Program Requirements. Defined Responsibilities Following the Declaration of a Disaster or Extreme EmergentPage 123 DISASTER POLICY Including Extreme Emergent Situations (EES) The University of Connecticut
Oliver, Douglas L.
Ten-year retrospective: OPEC and the world oil market
This paper reviews the main events in the world oil market since 1973 and some major explanations as to what happened and why (Section I). Then there is a discussion of some projections for the next two decades and of some implications of various theories about OPEC's decisionmaking process (Section II). Section III summarizes what we have learned about modeling OPEC and the world oil market. This includes: the dominant theoretical approach based on the wealth-maximization model of Harold Hotelling (1931); the simulation approach most common in the applied literature, which envisages target-capacity-utilization pricing by OPEC; and the difficult problem of modeling price behavior during disruptions. Finally, Section IV discusses some important unresolved issues, both theoretical and empirical. A variety of contributions to the literature are considered, but the discussion pays special attention to two important recent works. One is the book OPEC Behavior and World Oil Prices (1982) (EAPA 9:3899) edited by James Griffin and David Teece, an important collection of papers on OPEC and world oil, prepared for a 1981 conference at the University of Houston. The other is the 1980 to 1981 world oil study by the Energy Modeling Forum of Stanford Univesity, which involved ten prominent models of the world oil market. 31 references.
Gately, D.
Buildings Included on EMS Reports"
Office of Legacy Management Office of Legacy Management Buildings Included on EMS Reports" "Site","Property Name","Property ID","GSF","Incl. in Water Baseline (CY2007)","Water Baseline (sq. ft.)","Water CY2008 (sq. ft.)","Water CY2009 (sq. ft.)","Water Notes","Incl. in Energy Baseline (CY2003)","Energy Baseline (sq. ft.)","CY2008 Energy (sq. ft.)","CY2009 Energy (sq. ft.)","Energy Notes","Included as Existing Building","CY2008 Existing Building (sq. ft.)","Reason for Building Exclusion" "Column Totals",,"Totals",115139,,10579,10579,22512,,,3183365,26374,115374,,,99476 "Durango, CO, Disposal/Processing Site","STORAGE SHED","DUD-BLDG-STORSHED",100,"no",,,,,"no",,,,"OSF","no",,"Less than 5,000 GSF"
As the 20th century draws to a close, both individual countries and the world community face challenging problems related to the supply and use energy. These include local and regional environmental impacts, the prospect of global climate and sea level change associated with the greenhouse effect, and threats to international relations in connection with oil supply or nuclear proliferation. For developing countries, the financial cost of providing energy to provide basic needs and fuel economic development pose an additional burden. To assess the magnitude of future problems and the potential effectiveness of response strategies, it is important to understand how and why energy use has changed in the post and where it is heading. This requires study of the activities for which energy is used, and of how people and technology interact to provide the energy services that are desired. The authors and their colleagues have analyzed trends in energy use by sector for most of the world's major energy-consuming countries. The approach we use considers three key elements in each sector: the level of activity, structural change, and energy intensity, which expresses the amount of energy used for various activities. At a disaggregated level, energy intensity is indicative of energy efficiency. But other factors besides technical efficiency also shape intensity.
Power generation method including membrane separation
A method for generating electric power, such as at, or close to, natural gas fields. The method includes conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas by means of a membrane separation step. This step creates a leaner, sweeter, drier gas, which is then used as combustion fuel to run a turbine, which is in turn used for power generation.
Lokhandwala, Kaaeid A. (Union City, CA)
Electric power monthly, September 1990. [Glossary included
The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)
Nuclear reactor shield including magnesium oxide
An improvement in nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux, the reactor shielding including means providing structural support, neutron moderator material, neutron absorber material and other components as described below, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron.
Rouse, Carl A. (Del Mar, CA); Simnad, Massoud T. (La Jolla, CA)
Hawaii energy strategy project 2: Fossil energy review. Task 1: World and regional fossil energy dynamics
This report in the Hawaii Energy Strategy Project examines world and regional fossil energy dynamics. The topics of the report include fossil energy characteristics, the world oil industry including reserves, production, consumption, exporters, importers, refining, products and their uses, history and trends in the global oil market and the Asia-Pacific market; world gas industry including reserves, production, consumption, exporters, importers, processing, gas-based products, international gas market and the emerging Asia-Pacific gas market; the world coal industry including reserves, classification and quality, utilization, transportation, pricing, world coal market, Asia-Pacific coal outlook, trends in Europe and the Americas; and environmental trends affecting fossil fuels. 132 figs., 46 tabs.
Breazeale, K. [ed.; Isaak, D.T.; Yamaguchi, N.; Fridley, D.; Johnson, C.; Long, S.
Profile of World Uranium Enrichment Programs-2009
It is generally agreed that the most difficult step in building a nuclear weapon is acquiring fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, whereas HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use as fuel for nuclear reactors to generate electricity. However, the same equipment used to produce LEU for nuclear reactor fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is not diverted or enriched to HEU. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 56 million kilogram separative work units (SWU) per year, with 22.5 million in gaseous diffusion and more than 33 million in gas centrifuge plants. Another 34 million SWU/year of capacity is under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique of the future but has yet to be demonstrated commercially. In the early 1980s, six countries developing gas centrifuge technology (United States, United Kingdom, Germany, the Netherlands, Japan, and Australia) along with the International Atomic Energy Agency and the European Atomic Energy Community began developing effective safeguards techniques for GCEPs. This effort was known as the Hexapartite Safeguards Project (HSP). The HSP had the goal of maximizing safeguards effectiveness while minimizing the cost to the operator and inspectorate, and adopted several recommendations, such as the acceptance of limited-frequency unannounced access inspections in cascade halls, and the use of nondestructive assay measurements and tamper-indicating seals. While only the HSP participants initially committed to implementing all the measures of the approach, it has been used as a model for the safeguards applied to GCEPs in additional states. Uranium enrichment capacity has continued to expand on all fronts in the last few years. GCEP capacity is expanding in anticipation of the eventual shutdown of the less-efficient GDPs, the termination of the U.S.-Russia HEU blend-down program slated for 2013, and the possible resurgence of nuclear reactor construction as part of an expected 'Nuclear Renaissance'. Overall, a clear trend in the world profile of uranium enrichment plant operation is the continued movement towards multinational projects driven by commercial and economic interests. Along this vein, the safeguards community is continuing to develop new safeguards techniques and technologies that are not overly burdensome to enrichment plant operators while delivering more effective and efficient results. This report provides a snapshot overview of world enrichment capacity in 2009, including profiles of the uranium enrichment programs of individual states. It is a revision of a 2007 report on the same topic; significant changes in world enrichment programs between the previous and current reports are emphasized. It is based entirely on open-source information, which is dependent on published sources and may theref
Laughter, Mark D [ORNL
Summary World Natural Gas Data (from World on the Edge) | OpenEI
data GDR Community Login | Sign Up Search Facebook icon Twitter icon Summary World Natural Gas Data (from World on the Edge) Dataset Summary Description This dataset...
World Oil Refining Logistics Demand Model
Reducing the Cost of Thermal Energy Storage for Parabolic Trough Solar Power Plants
Thermal energy storage systems using phase change materials were evaluated for trough systems that use oil, steam, and high temperature salts as heat transfer fluids. A variety of eutectic salts and metal alloys were considered as phase change materials in a cascaded arrangement. Literature values of specific heat, latent heat, density, and other thermophysical properties were used in initial analyses. Testing laboratories were contracted to measure properties for candidate materials for comparison to the literature and for updating the models. A TRNSYS model from Phase 1 was further developed for optimizing the system, including a novel control algorithm. A concept for increasing the bulk thermal conductivity of the phase change system was developed using expanded metal sheets. Outside companies were contracted to design and cost systems using platecoil heat exchangers immersed in the phase change material. Laboratory evaluations of the one-dimensional and three-dimensional behavior of expanded metal sheets in a low conductivity medium were used to optimize the amount of thermal conductivity enhancement. The thermal energy storage systems were compared to baseline conventional systems. The best phase change system found in this project, which was for the high temperature plant, had a projected cost of $25.2 per kWhth, The best system also had a cost that was similar to the base case, a direct two-tank molten salt system.
Gawlik, Keith
Thermovoltaic semiconductor device including a plasma filter
A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.
Baldasaro, Paul F. (Clifton Park, NY)
Opec squabbling sparks surge in world production
In the second half of 1988 Opec member nations began on cheating on their quotas. The resultant 11% surge in Middle Eastern production propelled world output to an average of 58.5 MMbopd. This paper presents an analysis of major oil producing countries of the world and a listing, by country, of world crude oil and condensate production for 1987 and 1988.
Virtual worlds as a medium for advertising
Online virtual worlds, such as Second Life, are rapidly becoming recognized as a technology of substantial future importance for marketers and advertisers. Many of these virtual worlds provide the potential medium for very rich and varied new and enhanced ... Keywords: MMOG, advertising, marketing, online game, second life, virtual world
Stuart Barnes
SunLab: Advancing Concentrating Solar Power Technology
Concentrating solar power (CSP) technologies, including parabolic troughs, power towers, and dish/engines, have the potential to provide the world with tens of thousands of megawatts of clean, renewable, cost-competitive power.
Energy Department Advances Research on Methane Hydrates - the World's
Research on Methane Hydrates - the Research on Methane Hydrates - the World's Largest Untapped Fossil Energy Resource Energy Department Advances Research on Methane Hydrates - the World's Largest Untapped Fossil Energy Resource August 31, 2012 - 1:00pm Addthis Washington, DC - The Energy Department today announced the selection of 14 new research projects across 11 states that will be a part of an expanding portfolio of projects designed to increase our understanding of methane hydrates' potential as a future energy supply. Methane hydrates are 3D ice-lattice structures with natural gas locked inside, and are found both onshore and offshore - including under the Arctic permafrost and in ocean sediments along nearly every continental shelf in the world. Today's projects build on the completion of a successful, unprecedented test
Carbon Dioxide Information Analysis Center's World Data Center home page
image image World Data Centers An Introduction Changes Since the International Geophysical Year Principles of Operation Responsibilities of WDCs Contribution of Data Exchange of Data Among the WDCs Data Dissemination Other Activities Prepared from publications of the World Data Centers with additional input from the National Academy of Sciences. The WDC system includes components in the Russia, Japan, and An Introduction The World Data Centers (WDCs) were established in 1957 to provide archives for the data gathered during the International Geophysical Year (IGY). Initially, the academies of science participating in the IGY established WDCs for one or more IGY disciplines, operated them at their own expense in accord with the principles laid down by the Comite Special de I'Annee
Energy Department Advances Research on Methane Hydrates - the Energy Department Advances Research on Methane Hydrates - the World's Largest Untapped Fossil Energy Resource Energy Department Advances Research on Methane Hydrates - the World's Largest Untapped Fossil Energy Resource August 31, 2012 - 1:20pm Addthis News Media Contact (202) 586-4940 WASHINGTON, D.C. - The Energy Department today announced the selection of 14 new research projects across 11 states that will be a part of an expanding portfolio of projects designed to increase our understanding of methane hydrates' potential as a future energy supply. Methane hydrates are 3D ice-lattice structures with natural gas locked inside, and are found both onshore and offshore - including under the Arctic permafrost and in ocean sediments along nearly every continental shelf in the world.
Models of Procyon A including seismic constraints
Detailed models of Procyon A based on new asteroseismic measurements by Eggenberger et al (2004) have been computed using the Geneva evolution code including shellular rotation and atomic diffusion. By combining all non-asteroseismic observables now available for Procyon A with these seismological data, we find that the observed mean large spacing of 55.5 +- 0.5 uHz favours a mass of 1.497 M_sol for Procyon A. We also determine the following global parameters of Procyon A: an age of t=1.72 +- 0.30 Gyr, an initial helium mass fraction Y_i=0.290 +- 0.010, a nearly solar initial metallicity (Z/X)_i=0.0234 +- 0.0015 and a mixing-length parameter alpha=1.75 +- 0.40. Moreover, we show that the effects of rotation on the inner structure of the star may be revealed by asteroseismic observations if frequencies can be determined with a high precision. Existing seismological data of Procyon A are unfortunately not accurate enough to really test these differences in the input physics of our models.
P. Eggenberger; F. Carrier; F. Bouchy
Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss: Preprint
The overall efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The overall efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain an overall efficiency curve. Further, it presents a new way to plot efficiency that is more robust over a range of receiver operating temperatures.
Kutscher, C.; Burkholder, F.; Stynes, K.
This 2-page fact sheet provides general information regarding Clean Cities International, including background, successful activities, importance of partnerships, accomplishments, and plans.
Future technologies for our future world Research in the School of Electronics and Computer Science
ECS Research groups Communications 12 Dependable Systems and Software Engineering 14 Electrical Power for our future world This brochure presents an overview of the School's research, profiling some of our of innovation characterizes all the School's endeavours. Our recent `world firsts' include harvesting energy
Southampton, University of