Sample records for iterative systems analyses

  1. ETR/ITER systems code

    SciTech Connect

    Barr, W.L.; Bathke, C.G.; Brooks, J.N.; Bulmer, R.H.; Busigin, A.; DuBois, P.F.; Fenstermacher, M.E.; Fink, J.; Finn, P.A.; Galambos, J.D.; Gohar, Y.; Gorker, G.E.; Haines, J.R.; Hassanein, A.M.; Hicks, D.R.; Ho, S.K.; Kalsi, S.S.; Kalyanam, K.M.; Kerns, J.A.; Lee, J.D.; Miller, J.R.; Miller, R.L.; Myall, J.O.; Peng, Y-K.M.; Perkins, L.J.; Spampinato, P.T.; Strickler, D.J.; Thomson, S.L.; Wagner, C.E.; Willms, R.S.; Reid, R.L. (ed.)

    1988-04-01

    A tokamak systems code capable of modeling experimental test reactors has been developed and is described in this document. The code, named TETRA (for Tokamak Engineering Test Reactor Analysis), consists of a series of modules, each describing a tokamak system or component, controlled by an optimizer/driver. This code development was a national effort in that the modules were contributed by members of the fusion community and integrated into a code by the Fusion Engineering Design Center. The code has been checked out on the Cray computers at the National Magnetic Fusion Energy Computing Center and has satisfactorily simulated the Tokamak Ignition/Burn Experimental Reactor II (TIBER) design. A feature of this code is the ability to perform optimization studies through the use of a numerical software package, which iterates prescribed variables to satisfy a set of prescribed equations or constraints. This code will be used to perform sensitivity studies for the proposed International Thermonuclear Experimental Reactor (ITER). 22 figs., 29 tabs.

  2. RAMI analysis for ITER fuel cycle system

    Microsoft Academic Search

    K. Okayama; D. van Houtte; F. Sagot; S. Maruyama

    2011-01-01

    ITER is the first fusion device designed to continuously process DT (Deuterium–Tritium) plasma exhaust and supply recycled fuel in a closed loop, using a FCS (Fuel Cycle System) which includes tritium plant, vacuum system, and fuelling and wall conditioning systems. In addition, as an important step towards the commercially viable power plant, ITER has an ambitious inherent availability target of

  3. Value iteration for (switched) homogeneous systems

    E-print Network

    Dahleh, Munther A.

    In this note, we prove that dynamic programming value iteration converges uniformly for discrete-time homogeneous systems and continuous-time switched homogeneous systems. For discrete-time homogeneous systems, rather than ...

  4. Assessment of CONTAIN and MELCOR for performing LOCA and LOVA analyses in ITER

    SciTech Connect

    Merrill, B.J.; Hagrman, D.L.; Gaeta, M.J.; Petti, D.A.

    1994-09-01

    This report describes the results of an assessment of the CONTAIN and MELCOR computer codes for ITER LOCA and LOVA applications. As part of the assessment, the results of running a test problem that describes an ITER LOCA are presented. It is concluded that the MELCOR code should be the preferred code for ITER severe accident thermal hydraulic analyses. This code will require the least modification to be appropriate for calculating thermal hydraulic behavior in ITER relevant conditions that include vacuum, cryogenics, ITER temperatures, and the presence of a liquid metal test module. The assessment of the aerosol transport models in these codes concludes that several modifications would have to be made to CONTAIN and/or MELCOR to make them applicable to the aerosol transport part of severe accident analysis in ITER.

  5. Iter

    NASA Astrophysics Data System (ADS)

    Iotti, Robert

    2015-04-01

    ITER is an international experimental facility being built by seven Parties to demonstrate the long term potential of fusion energy. The ITER Joint Implementation Agreement (JIA) defines the structure and governance model of such cooperation. There are a number of necessary conditions for such international projects to be successful: a complete design, strong systems engineering working with an agreed set of requirements, an experienced organization with systems and plans in place to manage the project, a cost estimate backed by industry, and someone in charge. Unfortunately for ITER many of these conditions were not present. The paper discusses the priorities in the JIA which led to setting up the project with a Central Integrating Organization (IO) in Cadarache, France as the ITER HQ, and seven Domestic Agencies (DAs) located in the countries of the Parties, responsible for delivering 90%+ of the project hardware as Contributions-in-Kind and also financial contributions to the IO, as ``Contributions-in-Cash.'' Theoretically the Director General (DG) is responsible for everything. In practice the DG does not have the power to control the work of the DAs, and there is not an effective management structure enabling the IO and the DAs to arbitrate disputes, so the project is not really managed, but is a loose collaboration of competing interests. Any DA can effectively block a decision reached by the DG. Inefficiencies in completing design while setting up a competent organization from scratch contributed to the delays and cost increases during the initial few years. So did the fact that the original estimate was not developed from industry input. Unforeseen inflation and market demand on certain commodities/materials further exacerbated the cost increases. Since then, improvements are debatable. Does this mean that the governance model of ITER is a wrong model for international scientific cooperation? I do not believe so. Had the necessary conditions for success been present at the beginning, ITER would be in far better shape. As is, it can provide good lessons to avoid the same problems in the future. The ITER Council is now applying those lessons. A very experienced new Director General has just been appointed. He has instituted a number of drastic changes, but still within the governance of the JIA. Will there changes be effective? Only time will tell, but I am optimistic.

  6. Nuclear modules of ITER tokamak systems code

    SciTech Connect

    Gohar, Y.; Baker, C.; Brooks, J.; Finn, P.; Hassanein, A.; Willms, S.; Barr, W.; Bushigin, A.; Kalyanam, K.M.; Haines, J.

    1987-10-01

    Nuclear modules were developed to model various reactor components in the ITER systems code. Several design options and cost algorithms are included for each component. The first wall, blanket and shield modules calculate the beryllium zone thickness, the disruptions results, the nuclear responses in different components including the toroidal field coils. Tungsten shield/water coolant/steel structure and steel shield/water coolant are the shield options for the inboard and outboard sections of the reactor. Lithium nitrate dissolved in the water coolant with a variable beryllium zone thickness in the outboard section of the reactor provides the tritium breeding capability. The reactor vault module defines the thickness of the reactor wall and the roof based on the dose equivalent during operation including skyshine contribution. The impurity control module provides the design parameters for the divertor including plate design, heat load, erosion rate, tritium permeation through the plate material to the coolant, plasma contamination by sputtered impurities, and plate lifetime. Several materials: Be, C, V, Mo, and W can be used for the divertor plate to cover a range of plasma edge temperatures. The tritium module calculates tritium and deuterium flow rates for the reactor plant. The tritium inventory in the fuelers, neutral beams, vacuum pumps, impurity control, first wall, and blanket is calculated. Tritium requirements are provided for different operating conditions. The nuclear models are summarized in this paper including the different design options and key analyses of each module. 39 refs., 3 tabs.

  7. The ITER in-vessel system

    SciTech Connect

    Lousteau, D.C.

    1994-09-01

    The overall programmatic objective, as defined in the ITER Engineering Design Activities (EDA) Agreement, is to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes. The ITER EDA Phase, due to last until July 1998, will encompass the design of the device and its auxiliary systems and facilities, including the preparation of engineering drawings. The EDA also incorporates validating research and development (R&D) work, including the development and testing of key components. The purpose of this paper is to review the status of the design, as it has been developed so far, emphasizing the design and integration of those components contained within the vacuum vessel of the ITER device. The components included in the in-vessel systems are divertor and first wall; blanket and shield; plasma heating, fueling, and vacuum pumping equipment; and remote handling equipment.

  8. ITER prototype fast plant system controller

    Microsoft Academic Search

    B. Gonçalves; J. Sousa; B. B. Carvalho; A. P. Rodrigues; M. Correia; A. Batista; J. Vega; M. Ruiz; J. M. López; R. Castro; A. Wallander; N. Utzel; P. Makijarvi; S. Simrock; A. Neto; D. Alves; D. F. Valcárcel; P. Lousă; F. Piedade; L. Fernandes

    2011-01-01

    ITER CODAC Design identified the need for slow and fast control plant systems, based respectively on industrial automation technology with maximum sampling rates below 100Hz, and on embedded technology with higher sampling rates and more stringent real-time requirements. The fast system is applicable to diagnostics and plant systems in closed-control loops whose cycle times are below 1ms. Fast controllers will

  9. Analysing Java System Properties Implementation

    E-print Network

    Nierstrasz, Oscar

    Analysing Java System Properties Implementation Supplementary documentation to the Bachelor. It introduces the Java Platform Debugger Architecture (JPDA), looks at the Java Debug Interface (JDI;Analysing Java System Properties Contents David Wettstein, 8. Dezember 2013 3 Contents 1 Standard System

  10. An integrated design evaluation system supporting thermal-structural iterations

    Microsoft Academic Search

    Peter Eliasson; Ola Isaksson; Peter Jeppsson; Göran Fernström; Tobias C Larsson

    1998-01-01

    In the design of high temperature components, design evaluation often requires an iterative procedure between thermal fluid and thermal structural simulations An integrated computer system providing an iterative environment for the multidisciplinary simulations re quired has been developed. The system supports iterations between thermal fluid and thermal structural simulations using two different commercial simulation packages. Traditionally, fluid and structural analysis

  11. The ITER Radial Neutron Camera Detection System

    SciTech Connect

    Marocco, D.; Belli, F.; Esposito, B.; Petrizzi, L.; Riva, M. [Associazione ENEA-Euratom sulla Fusione, C.R. Frascati, C.P. 65, I-00044 Frascati (Roma) (Italy); Bonheure, G. [Laboratory for Plasma Physics, Association 'Euratom-Belgian State', Royal Military Academy, Avenue dela Renaissance, 30, B-1000 Brussels (Belgium); Kaschuck, Y. [TRINITI, Troitsk 142190, Moscow Region (Russian Federation)

    2008-03-12

    A multichannel neutron detection system (Radial Neutron Camera, RNC) will be installed on the ITER equatorial port plug 1 for total neutron source strength, neutron emissivity/ion temperature profiles and n{sub t}/n{sub d} ratio measurements [1]. The system is composed by two fan shaped collimating structures: an ex-vessel structure, looking at the plasma core, containing tree sets of 12 collimators (each set lying on a different toroidal plane), and an in-vessel structure, containing 9 collimators, for plasma edge coverage. The RNC detecting system will work in a harsh environment (neutron fiux up to 10{sup 8}-10{sup 9} n/cm{sup 2} s, magnetic field >0.5 T or in-vessel detectors), should provide both counting and spectrometric information and should be flexible enough to cover the high neutron flux dynamic range expected during the different ITER operation phases. ENEA has been involved in several activities related to RNC design and optimization [2,3]. In the present paper the up-to-date design and the neutron emissivity reconstruction capabilities of the RNC will be described. Different options for detectors suitable for spectrometry and counting (e.g. scintillators and diamonds) focusing on the implications in terms of overall RNC performance will be discussed. The increase of the RNC capabilities offered by the use of new digital data acquisition systems will be also addressed.

  12. a Gluing Lemma for Iterated Function Systems

    NASA Astrophysics Data System (ADS)

    Kamae, Teturo; Luo, Jun; Tan, Bo

    2015-05-01

    We obtain a special version of gluing lemma related to the theory of iterated function systems (IFS). As an application, we verify that a family of concrete n-dimensional self-affine tiles {Tn, r : 0 ? r < 3, n ? 3} are homeomorphic with the unit cube [0,1]n. The tiles Tn, r are "nontrivial" in the sense that each of them is neither a self-affine polytope nor the product of an interval with an (n - 1)-dimensional self-affine tile.

  13. Iterative multiuser detection techniques for CDMA systems

    E-print Network

    Du, Xuechao

    2002-01-01

    detector, iterative improved parallel interference cancellation, gradient descent algorithm and slowest-descent algorithm, are studied. Two new iterative multiuser detection methods, namely the simplified low-complexity approximate SISO multiuser detector...

  14. Overview of ITER magnet system and European contribution

    Microsoft Academic Search

    C. Sborchia; E. Barbero Soto; R. Batista; B. Bellesia; A. Bonito Oliva; E. Boter Rebollo; T. Boutboul; E. Bratu; J. Caballero; M. Cornelis; J. Fanthome; R. Harrison; M. Losasso; A. Portone; H. Rajainmaki; P. Readman; P. Valente

    2011-01-01

    The superconducting magnet system of ITER consists of four main sub-systems: Toroidal Field (TF) coils, Central Solenoid (CS) coils; Poloidal Field (PF) coils; and Correction Coils (CC). Like many other ITER systems, the magnet components are supplied in-kind by six Domestic Agencies (DAs). The technical specifications, manufacturing processes and procedures required to fabricate these components are particularly challenging. The management

  15. QUANTUM STOCHASTIC PROCESSES, QUANTUM ITERATED FUNCTION SYSTEMS AND ENTROPY

    E-print Network

    Lopes, Artur Oscar

    HN be a Hilbert space of finite dimension N. If a quantum system is in a certain known state | HNQUANTUM STOCHASTIC PROCESSES, QUANTUM ITERATED FUNCTION SYSTEMS AND ENTROPY A. BARAVIERA*, C. F to Quantum Iterated Function Systems (QIFS). We discuss ques- tions related to the Markov property and we

  16. Iteration in Systems Analysis and Design: Cognitive Processes and Representational Artifacts

    Microsoft Academic Search

    Nicholas Berente; Kalle Lyytinen

    2005-01-01

    The idea of iteration is inherent to systems analysis and design methodologies and practices. In this essay we explore the notion of iteration, and distinguish two dimensions of iteration: iterations inherent in cognitive processes and iterations over representational artifacts. Cognitive iterations can be concerned with the design; the design process; or stages within the design process. Representational artifacts can take

  17. A lower hybrid current drive system for ITER

    NASA Astrophysics Data System (ADS)

    Hoang, G. T.; Bécoulet, A.; Jacquinot, J.; Artaud, J. F.; Bae, Y. S.; Beaumont, B.; Belo, J. H.; Berger-By, G.; Bizarro, Joăo P. S.; Bonoli, P.; Cho, M. H.; Decker, J.; Delpech, L.; Ekedahl, A.; Garcia, J.; Giruzzi, G.; Goniche, M.; Gormezano, C.; Guilhem, D.; Hillairet, J.; Imbeaux, F.; Kazarian, F.; Kessel, C.; Kim, S. H.; Kwak, J. G.; Jeong, J. H.; Lister, J. B.; Litaudon, X.; Magne, R.; Milora, S.; Mirizzi, F.; Namkung, W.; Noterdaeme, J. M.; Park, S. I.; Parker, R.; Peysson, Y.; Rasmussen, D.; Sharma, P. K.; Schneider, M.; Synakowski, E.; Tanga, A.; Tuccillo, A.; Wan, Y. X.

    2009-07-01

    A 20 MW/5 GHz lower hybrid current drive (LHCD) system was initially due to be commissioned and used for the second mission of ITER, i.e. the Q = 5 steady state target. Though not part of the currently planned procurement phase, it is now under consideration for an earlier delivery. In this paper, both physics and technology conceptual designs are reviewed. Furthermore, an appropriate work plan is also developed. This work plan for design, R&D, procurement and installation of a 20 MW LHCD system on ITER follows the ITER Scientific and Technical Advisory Committee (STAC) T13-05 task instructions. It gives more details on the various scientific and technical implications of the system, without presuming on any work or procurement sharing amongst the possible ITER partnersb The LHCD system of ITER is not part of the initial cost sharing.. This document does not commit the Institutions or Domestic Agencies of the various authors in that respect.

  18. ITER

    SciTech Connect

    Cowley, Steve

    2005-10-10

    This year six international partners have signed up to construct the first burning plasma experiment -- ITER -- in the South of France.It is over 50 years since the beginning of national programs to produce controlled fusion energy. The challenge of fusion energy has proven harder than was first anticipated. In this Colloquium Steve Cowley from UCLA will explain the scientific issues and how the difficulties have been overcome.

  19. Interval iteration for zeros of systems of equations

    Microsoft Academic Search

    A. Neumaier; Angewandte Mathematik

    1985-01-01

    Easily verifiable existence and convergence conditions are given for a class of interval iteration algorithms for the enclosure of a zero of a system of nonlinear equations. In particular, a quadratically convergent method is obtained which throughout the iteration uses the same interval enclosure of the derivative.

  20. ITER neutral beam system US conceptual design

    SciTech Connect

    Purgalis, P.

    1990-09-01

    In this document we present the US conceptual design of a neutral beam system for International Thermonuclear Experimental Reactor (ITER). The design incorporates a barium surface conversion D{sup {minus}} source feeding a linear array of accelerator channels. The system uses a dc accelerator with electrostatic quadrupoles for strong focusing. A high voltage power supply that is integrated with the accelerator is presented as an attractive option. A gas neutralizer is used and residual ions exiting the neutralizer are deflected to water-cooled dumps. Cryopanels are located at the accelerator exit to pump excess gas from the source and the neutralizer, and in the ion dump cavity to pump re-neutralized ions and neutralizer gas. All the above components are packaged in compact identical, independent modules which can be removed for remote maintenance. The neutral beam system delivers 75 MW of DO at 1.3 MeV, into three ports with a total of 9 modules arranged in stacks of three modules per port . To increase reliability each module is designed to deliver up to 10 MW; this allows eight modules operating at partial capacity to deliver the required power in the event one module is out of service, and provides 20% excess capacity to improve availability. Radiation protection is provided by shielding and by locating critical components in the source and accelerator 46.5 m from the torus centerline. Neutron shielding in the drift duct and neutralizer provides the added feature of limiting conductance and thus reducing gas flow to and from the torus.

  1. Iterative multiuser detection techniques for CDMA systems 

    E-print Network

    Du, Xuechao

    2002-01-01

    &(s) according to o, (s) = Q &r, , (s') P [6&(s', s)] s' &r, (s) = c, &r&(s), (2. 11) (2. 12) Now by a sin&pic induction we obtain &r& r(s) = (P, : ?c, )&r?(s) = C?c&?(s). Thus t ? & we can write n, (s) as g, , C, , o, , (s')P[6, (s', s)] o, (s) o, (s) (2... is the number of iterations which depends on the number of users and typically varies between 4 ancl 10. Thc algorithm for improv&&d iterative parallel interfcr&a&ce cancellation(PIC) is summa&ised as follows. Algorithm 4 [Improved Iterative PIC for AWCN...

  2. Engineering design of ITER prototype Fast Plant System Controller

    Microsoft Academic Search

    B. Gonçalves; J. Sousa; B. Carvalho; A. P. Rodrigues; M. Correia; A. Batista; J. Vega; M. Ruiz; J. M. Lo?pez; R. C. Rojo; A. Wallander; N. Utzel; A. Neto; D. Alves; D. Valca?rcel

    2010-01-01

    ITER CODAC Design identified the need for two types of Plant System. Slow control plant system, based on industrial automation technology with maximum sampling rates below 100 Hz, and fast control plant system based on embedded technology with higher sampling rates and more stringent realtime requirements. The latter is applicable to diagnostics and Plant Systems in closed-control loops whose cycle

  3. Circuit Analyses of the Filament Ion Source Power Supplies for the ITER Neutral Beam Test Facility

    Microsoft Academic Search

    M. Bigi; L. Zanotto

    2005-01-01

    This paper describes circuit simulations of the filament heating circuit for the neutral beam test facility of the international thermonuclear experimental reactor (ITER). The novel features of ITER filament heating circuit are studied both in normal operation and under fault conditions. The proposed scheme is found capable of performing as required and results are illustrated useful for further detailing of

  4. Engineering Design of ITER Prototype Fast Plant System Controller

    Microsoft Academic Search

    B. Goncalves; J. Sousa; B. Carvalho; A. P. Rodrigues; M. Correia; A. Batista; J. Vega; M. Ruiz; J. M. Lopez; R. Castro Rojo; A. Wallander; N. Utzel; A. Neto; D. Alves; D. Valcarcel

    2011-01-01

    The ITER control, data access and communication (CODAC) design team identified the need for two types of plant systems. A slow control plant system is based on industrial au- tomation technology with maximum sampling rates below 100 Hz, and a fast control plant system is based on embedded technology with higher sampling rates and more stringent real-time require- ments than

  5. Design of fast tuning elements for the ITER ICH system

    SciTech Connect

    Swain, D.W.; Goulding, R.H.

    1996-05-01

    The coupling between the ion cyclotron (IC) antenna and the ITER plasma (as expressed by the load resistance the antenna sees) will experience relatively fast variations due to plasma edge profile modifications. If uncompensated, these will cause an increase in the amount of power reflected back to the transmitter and ultimately a decrease in the amount of radio frequency (rf) power to the plasma caused by protective suppression of the amount of rf power generated by the transmitter. The goals of this task were to study several alternate designs for a tuning and matching (T&M) system and to recommend some research and development (R&D) tasks that could be carried out to test some of the most promising concepts. Analyses of five different T&M configurations are presented in this report. They each have different advantages and disadvantages, and the choice among them must be made depending on the requirements for the IC system. Several general conclusions emerge from our study: The use of a hybrid splitter as a passive reflected-power dump [``edge localized mode (ELM)-dump``] appears very promising; this configuration will protect the rf power sources from reflected power during changes in plasma loading due to plasma motion or profile changes (e.g., ELM- induced changes in the plasma scrape-off region) and requires no active control of the rf system. Trade-offs between simplicity of design and capability of the system must be made. Simple system designs with few components near the antenna either have high voltages over considerable distances of transmission lines, or they are not easily tuned to operate at different frequencies. Designs using frequency shifts and/or fast tuning elements can provide fast matching over a wide range of plasma loading; however, the designs studied here require components near the antenna, complicating assembly and maintenance. Capacitor-tuned resonant systems may offer a good compromise.

  6. Tritium module for ITER/Tiber system code

    SciTech Connect

    Finn, P.A.; Willms, S.; Busigin, A.; Kalyanam, K.M.

    1988-01-01

    A tritium module was developed for the ITER/Tiber system code to provide information on capital costs, tritium inventory, power requirements and building volumes for these systems. In the tritium module, the main tritium subsystems/emdash/plasma processing, atmospheric cleanup, water cleanup, blanket processing/emdash/are each represented by simple scaleable algorithms. 6 refs., 2 tabs.

  7. Initial results of systems analysis ETR\\/ITER design space

    Microsoft Academic Search

    Yueng Kay Martin Peng; John D Galambos; R. L. Reid; Dennis J Strickler

    1987-01-01

    Preliminary versions of the Engineering Test REactor (ETR) systems code TETRA (Tokamak Engineering Test Reactor Analysis), which determines design solutions by the method of constrained optimization, are used to characterize the International Thermonuclear Experimental Reactor (ITER) and its design parameter space. They find that the physics objectives of high ignition margin and high plasma current lead to minimum size at

  8. Iterative learning control for singularly perturbed systems Konstantin E. Avrachenkov \\Lambda Anatoly A. Pervozvanski y

    E-print Network

    Avrachenkov, Konstantin

    Iterative learning control for singularly perturbed systems Konstantin E. Avrachenkov \\Lambda Anatoly A. Pervozvanski y March 14, 1999 Abstract The singularly perturbed systems are described iterative learning con­ trol algorithms diverge in the presence of singular perturbations. The aim

  9. Large Scale Power System Computations: Applications of Iterative Techniques

    Microsoft Academic Search

    Dimitrios Chaniotis; M. A. Pai

    \\u000a Solution of large sparse linear Systems forms the core of power system computations whether it is power flow, dynamic Simulation\\u000a or state estimation. There is a continuous need to speed up this process by improved numerical algorithms. Iterative solver\\u000a techniques based on the Krylov subspace protection method offer an attractive alternative to the traditional LU factorization\\u000a methods because of the

  10. Iterative algorithms for large sparse linear systems on parallel computers

    NASA Technical Reports Server (NTRS)

    Adams, L. M.

    1982-01-01

    Algorithms for assembling in parallel the sparse system of linear equations that result from finite difference or finite element discretizations of elliptic partial differential equations, such as those that arise in structural engineering are developed. Parallel linear stationary iterative algorithms and parallel preconditioned conjugate gradient algorithms are developed for solving these systems. In addition, a model for comparing parallel algorithms on array architectures is developed and results of this model for the algorithms are given.

  11. Linear prediction image coding using iterated function systems

    Microsoft Academic Search

    Michele Nappi; Domenico Vitulano

    1999-01-01

    This paper presents a hybrid system to speed up image fractal encoding. The coding scheme, LP-IFS, consists of linear prediction (LP) and Iterated Functions Systems (IFS) applied in cascade on the image. The LP process employs a 2D auto-regressive model to estimate parameters for each block in the image partition; IFS are then used instead of adaptive quantizers to encode

  12. Status of Europe's contribution to the ITER EC system

    NASA Astrophysics Data System (ADS)

    Albajar, F.; Aiello, G.; Alberti, S.; Arnold, F.; Avramidis, K.; Bader, M.; Batista, R.; Bertizzolo, R.; Bonicelli, T.; Braunmueller, F.; Brescan, C.; Bruschi, A.; von Burg, B.; Camino, K.; Carannante, G.; Casarin, V.; Castillo, A.; Cauvard, F.; Cavalieri, C.; Cavinato, M.; Chavan, R.; Chelis, J.; Cismondi, F.; Combescure, D.; Darbos, C.; Farina, D.; Fasel, D.; Figini, L.; Gagliardi, M.; Gandini, F.; Gantenbein, G.; Gassmann, T.; Gessner, R.; Goodman, T. P.; Gracia, V.; Grossetti, G.; Heemskerk, C.; Henderson, M.; Hermann, V.; Hogge, J. P.; Illy, S.; Ioannidis, Z.; Jelonnek, J.; Jin, J.; Kasparek, W.; Koning, J.; Krause, A. S.; Landis, J. D.; Latsas, G.; Li, F.; Mazzocchi, F.; Meier, A.; Moro, A.; Nousiainen, R.; Purohit, D.; Nowak, S.; Omori, T.; van Oosterhout, J.; Pacheco, J.; Pagonakis, I.; Platania, P.; Poli, E.; Preis, A. K.; Ronden, D.; Rozier, Y.; Rzesnicki, T.; Saibene, G.; Sanchez, F.; Sartori, F.; Sauter, O.; Scherer, T.; Schlatter, C.; Schreck, S.; Serikov, A.; Siravo, U.; Sozzi, C.; Spaeh, P.; Spichiger, A.; Strauss, D.; Takahashi, K.; Thumm, M.; Tigelis, I.; Vaccaro, A.; Vomvoridis, J.; Tran, M. Q.; Weinhorst, B.

    2015-03-01

    The electron cyclotron (EC) system of ITER for the initial configuration is designed to provide 20MW of RF power into the plasma during 3600s and a duty cycle of up to 25% for heating and (co and counter) non-inductive current drive, also used to control the MHD plasma instabilities. The EC system is being procured by 5 domestic agencies plus the ITER Organization (IO). F4E has the largest fraction of the EC procurements, which includes 8 high voltage power supplies (HVPS), 6 gyrotrons, the ex-vessel waveguides (includes isolation valves and diamond windows) for all launchers, 4 upper launchers and the main control system. F4E is working with IO to improve the overall design of the EC system by integrating consolidated technological advances, simplifying the interfaces, and doing global engineering analysis and assessments of EC heating and current drive physics and technology capabilities. Examples are the optimization of the HVPS and gyrotron requirements and performance relative to power modulation for MHD control, common qualification programs for diamond window procurements, assessment of the EC grounding system, and the optimization of the launcher steering angles for improved EC access. Here we provide an update on the status of Europe's contribution to the ITER EC system, and a summary of the global activities underway by F4E in collaboration with IO for the optimization of the subsystems.

  13. VPI analyses of two-nucleon systems

    SciTech Connect

    Arndt, R.A.; Strakovsky, I.I.; Workman, R.L. [Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)

    1995-05-10

    We review our recent work on the two-nucleon system. In particular, we concentrate on analyses of the {pi}{ital d} elastic and {pi}{ital d}{r_arrow}{ital pp} scattering data bases. We discuss some problems arising in these analyses and combined analyses which include {ital pp} elastic scattering data. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  14. Iterative Channel Estimators in V-BLAST OFDM Systems

    Microsoft Academic Search

    Joonbeom Kim; Gordon L. Stüber

    2008-01-01

    An iterative pilot-symbol aided modulation (PSAM) channel estimation approach is proposed for vertical Bell Laboratories layered space-time (V-BLAST) orthogonal frequency division multiplexing systems operating on frequency-selective fading channels. Since the signals at the receive antennas are the superposition of signals from multiple transmit antennas, accurate channel estimates are crucial for good error performance. Furthermore, the time selectivity of the fading

  15. Overview of the ITER-FEAT LH system

    Microsoft Academic Search

    Ph. Bibet; F. Mirizzi; P. Bosia; L. Doceul; S. Kuzikov; K. Rantamäki; A. A. Tuccillo; F. Wasasterjna

    2003-01-01

    LH is considered to be used in ITER-FEAT steady-state scenario thanks to its highest current drive efficiency in the plasma outer part. The design of a 5 GHz, 20 MW CW LH system has been realised. That relies on a transmitter of 24 1-MW klystrons, and a circular oversized 60-m long transmission line feeding an antenna, based on the passive

  16. Iterated Function Systems and the Global Construction of Fractals

    Microsoft Academic Search

    M. F. Barnsley; S. Demko

    1985-01-01

    Iterated function systems (i.f.ss) are introduced as a unified way of generating a broad class of fractals. These fractals are often attractors for i.f.ss and occur as the supports of probability measures associated with functional equations. The existence of certain `p-balanced' measures for i.f.ss is established, and these measures are uniquely characterized for hyperbolic i.f.ss. The Hausdorff-Besicovitch dimension for some

  17. ITER prototype fast plant system controller based on ATCA platform

    Microsoft Academic Search

    B. Goncalves; J. Sousa; B. B. Carvalho; A. Batista; A. Neto; B. Santos; A. Duarte; D. Valcarcel; D. Alves; M. Correia; A. P. Rodrigues; P. F. Carvalho; J. Fortunato; P. J. Carvalho; M. Ruiz; J. Vega; R. Castro; J. M. Lopez; N. Utzel; P. Makijarvi; C. Leong; V. Bexiga; I. C. Teixeira; J. P. Teixeira; A. Barbalace; P. Lousa; J. Godinho; P. Mota

    2011-01-01

    The ITER Fast Plant System Controllers (FPSC) are based on embedded technologies and will be devoted to both data acquisition tasks (sampling rates >1 kSPS) and control purposes in closed-control loops whose cycle times are below 1 ms. Fast Controllers will be dedicated industrial controllers with the ability to: i) supervise other fast and\\/or slow controllers; ii) interface to actuators

  18. Conceptual Design of the ITER Plasma Control System

    NASA Astrophysics Data System (ADS)

    Snipes, J. A.

    2013-10-01

    The conceptual design of the ITER Plasma Control System (PCS) has been approved and the preliminary design has begun for the 1st plasma PCS. This is a collaboration of many plasma control experts from existing devices to design and test plasma control techniques applicable to ITER on existing machines. The conceptual design considered all phases of plasma operation, ranging from non-active H/He plasmas through high fusion gain inductive DT plasmas to fully non-inductive steady-state operation, to ensure that the PCS control functionality and architecture can satisfy the demands of the ITER Research Plan. The PCS will control plasma equilibrium and density, plasma heat exhaust, a range of MHD instabilities (including disruption mitigation), and the non-inductive current profile required to maintain stable steady-state scenarios. The PCS architecture requires sophisticated shared actuator management and event handling systems to prioritize control goals, algorithms, and actuators according to dynamic control needs and monitor plasma and plant system events to trigger automatic changes in the control algorithms or operational scenario, depending on real-time operating limits and conditions.

  19. Status of the ITER IC H&CD System

    NASA Astrophysics Data System (ADS)

    Lamalle, P. U.; Beaumont, B.; Gassmann, T.; Kazarian, F.; Arambhadiya, B.; Bora, D.; Jacquinot, J.; Mitteau, R.; Schüller, F. C.; Tanga, A.; Baruah, U.; Bhardwaj, A.; Kumar, R.; Mukherjee, A.; Singh, N. P.; Singh, R.; Goulding, R.; Rasmussen, D.; Swain, D.; Agarici, G.; Sartori, R.; Borthwick, A.; Davis, A.; Fanthome, J.; Hamlyn-Harris, C.; Hancock, A. D.; Kaye, A.; Lockley, D.; Nightingale, M.; Dumortier, P.; Durodié, F.; Grine, D.; Koch, R.; Louche, F.; Lyssoivan, A.; Messiaen, A.; Tamain, P.; Vervier, M.; Weynants, R. R.; Maggiora, R.; Milanesio, D.; Braun, F.; Noterdaeme, J.-M.; Vulliez, K.

    2009-11-01

    The ITER Ion Cyclotron Heating and Current Drive system will deliver 20 MW of radio frequency power to the plasma in quasi continuous operation during the different phases of the experimental programme. The system also has to perform conditioning of the tokamak first wall at low power between main plasma discharges. This broad range of requirements imposes a high flexibility and a high availability. The paper highlights the physics and design requirements on the IC system, the main features of its subsystems, the predicted performance, and the current procurement and installation schedule.

  20. Operation mode studies of the ITER cryodistribution system

    NASA Astrophysics Data System (ADS)

    Chang, Hyun-Sik; Serio, Luigi; Henry, Denis; Chalifour, Michel; Forgeas, Adrien

    2012-06-01

    In order to achieve and maintain the proper cryogenic conditions for fusion experiments, the ITER Cryogenic System has to cope with various operation modes as per the requirements of the superconducting (SC) magnets and the 4 K Cryopumps (CPs). The refrigerators, source of the cooling power, should operate as much as possible in a quasisteady- state manner for efficiency and reliability reasons, and also to optimize their cooling capacity. The cryogen-related transients generated or required by the magnets and CPs therefore have to be managed and smoothed inside the primary helium loops of the Cryodistribution (CD) cold boxes which distribute and recover the cooling flows. In this proceeding we will propose the internal-component layouts of the ITER CD cold boxes and demonstrate in terms of operation modes how they fulfill the duties of the Cryogenic System with respect to the ITER Tokamak. The methods foreseen for the smoothing of the cryogenic loads and optimization of the cooling power requirements will also be introduced.

  1. Trajectory Tracking of a Piezoelectric System using State Compensated Iterative Learning Control

    Microsoft Academic Search

    Chiang-Ju Chien; Fu-Shin Lee; Jhen-Cheng Wang

    2005-01-01

    This paper proposes a novel scheme of state compensated iterative learning control (ILC) for trajectory tracking of piezoelectric systems. The new ILC scheme adds a state compensation term to the conventional Arimoto-type ILC formula. The state compensation term is based on the difference of tracking error between the current and previous iterations. With the aid of this state compensation, iterative

  2. Development of a compact toroid fuelling system for ITER

    NASA Astrophysics Data System (ADS)

    Olynyk, G.; Morelli, J.

    2008-09-01

    A review of literature relevant to compact toroid (CT) injection is presented. A design is then developed for a repetitive-fire CT injection fuelling system for the ITER (2001) tokamak. Advantages of central over edge fuelling include plasma density control and higher deposition rates, implying lower tritium usage. The reference design offers 50 Pa m3 s-1 of 90%T/10%D fuelling. 1.29 mg CTs are injected at a rate of 50 Hz (in order to synchronize with the European power grid) and a speed of 300 km s-1. A new six-degree-of-freedom model of CT trajectory in the tokamak is developed and applied to the proposed injector design. The fueller is intended to work in parallel with the 400 Pa m3 s-1 edge gas puffing system and to replace the centrifuge pellet-injection system in the ITER (2001) reference design. Each injected CT adds only 0.68% to the plasma inventory, implying that the injection process will be non-disruptive. Power consumption will be approximately 15 MWe. The strengths of the design compared with the current pellet-injection system are highlighted.

  3. Advanced laser stratospheric monitoring systems analyses

    NASA Technical Reports Server (NTRS)

    Larsen, J. C.

    1984-01-01

    This report describes the software support supplied by Systems and Applied Sciences Corporation for the study of Advanced Laser Stratospheric Monitoring Systems Analyses under contract No. NAS1-15806. This report discusses improvements to the Langley spectroscopic data base, development of LHS instrument control software and data analyses and validation software. The effect of diurnal variations on the retrieved concentrations of NO, NO2 and C L O from a space and balloon borne measurement platform are discussed along with the selection of optimum IF channels for sensing stratospheric species from space.

  4. Status of the ITER heating neutral beam system

    NASA Astrophysics Data System (ADS)

    Hemsworth, R.; Decamps, H.; Graceffa, J.; Schunke, B.; Tanaka, M.; Dremel, M.; Tanga, A.; DeEsch, H. P. L.; Geli, F.; Milnes, J.; Inoue, T.; Marcuzzi, D.; Sonato, P.; Zaccaria, P.

    2009-04-01

    The ITER neutral beam (NB) injectors are the first injectors that will have to operate under conditions and constraints similar to those that will be encountered in a fusion reactor. These injectors will have to operate in a hostile radiation environment and they will become highly radioactive due to the neutron flux from ITER. The injectors will use a single large ion source and accelerator that will produce 40 A 1 MeV D- beams for pulse lengths of up to 3600 s. Significant design changes have been made to the ITER heating NB (HNB) injector over the past 4 years. The main changes are: Modifications to allow installation and maintenance of the beamline components with an overhead crane. The beam source vessel shape has been changed and the beam source moved to allow more space for the connections between the 1 MV bushing and the beam source. The RF driven negative ion source has replaced the filamented ion source as the reference design. The ion source and extractor power supplies will be located in an air insulated high voltage (-1 MV) deck located outside the tokamak building instead of inside an SF6 insulated HV deck located above the injector. Introduction of an all metal absolute valve to prevent any tritium in the machine to escape into the NB cell during maintenance. This paper describes the status of the design as of December 2008 including the above mentioned changes. The very important power supply system of the neutral beam injectors is not described in any detail as that merits a paper beyond the competence of the present authors. The R&D required to realize the injectors described in this paper must be carried out on a dedicated neutral beam test facility, which is not described here.

  5. THERMAL DESIGN OF THE ITER VACUUM VESSEL COOLING SYSTEM

    SciTech Connect

    Carbajo, Juan J [ORNL] [ORNL; Yoder Jr, Graydon L [ORNL] [ORNL; Kim, Seokho H [ORNL] [ORNL

    2010-01-01

    RELAP5-3D models of the ITER Vacuum Vessel (VV) Primary Heat Transfer System (PHTS) have been developed. The design of the cooling system is described in detail, and RELAP5 results are presented. Two parallel pump/heat exchanger trains comprise the design one train is for full-power operation and the other is for emergency operation or operation at decay heat levels. All the components are located inside the Tokamak building (a significant change from the original configurations). The results presented include operation at full power, decay heat operation, and baking operation. The RELAP5-3D results confirm that the design can operate satisfactorily during both normal pulsed power operation and decay heat operation. All the temperatures in the coolant and in the different system components are maintained within acceptable operating limits.

  6. Iterative Development of Visual Control Systems in a Research Vivarium

    PubMed Central

    Bassuk, James A.; Washington, Ida M.

    2014-01-01

    The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI) methodology, a lean approach to management at Seattle Children’s (Hospital, Research Institute, Foundation), would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart’s Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and selected Principles that guide implementation of the Toyota Production System. PMID:24736460

  7. Iterative development of visual control systems in a research vivarium.

    PubMed

    Bassuk, James A; Washington, Ida M

    2014-01-01

    The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI) methodology, a lean approach to management at Seattle Children's (Hospital, Research Institute, Foundation), would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart's Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and selected Principles that guide implementation of the Toyota Production System. PMID:24736460

  8. An iterative learning control theory for a class of nonlinear dynamic systems

    Microsoft Academic Search

    TAE-YONG KUC

    1992-01-01

    An iterative learning control scheme is presented for a class of nonlinear dynamic systems which includes holonomic systems as its subset. The control scheme is composed of two types of control methodology: a linear feedback mechanism and a feedforward learning strategy. At each iteration, the linear feedback provides stability of the system and keeps its state errors within uniform bounds.

  9. On modified Newton iterations for SPARK methods applied to constrained systems in mechanics

    E-print Network

    Jay, Laurent O.

    On modified Newton iterations for SPARK methods applied to constrained systems in mechanics Laurent Newton iterations to the solution of SPARK methods applied to a large class of overdetermined-algebraic equations, holonomic constraints, mechanical systems, nonholonomic constraints, SPARK methods. PACS: 02

  10. On modified Newton iterations for SPARK methods applied to constrained systems in mechanics

    E-print Network

    Jay, Laurent O.

    On modified Newton iterations for SPARK methods applied to constrained systems in mechanics Laurent Newton iterations to the solution of SPARK methods applied to a large class of overdetermined­algebraic equations, holonomic constraints, mechanical systems, nonholonomic constraints, SPARK methods. PACS: 02

  11. Iterative Non-hierarchical Cluster Analysis (INCA): a novel approach to analysing downhole logging and petrophysical data

    NASA Astrophysics Data System (ADS)

    Inwood, J.; Tudge, J.; Harvey, P.

    2012-12-01

    Iterative Non-Hierarchical Cluster Analysis (INCA) is a multivariate statistical approach used to analyse data, suited to large datasets where a defined number of clusters can be hypothesised. Although the fundamentals of this methododology are well-known, its use for the analysis of downhole logging and petrophysical measurements is a novel approach for quantitatively interpreting these datasets. Cluster analysis works by starting with k random clusters then grouping the set of data such that values within a cluster are more similar to each other than to those in the other clusters i.e. to minimise variability within a cluster and maximise variability between clusters. INCA provides a valuable tool for understanding downhole logging and petrophysical datasets by interpreting the weightings attached to each cluster in terms of petrophysical characteristics. The INCA program has been successfully used on datasets from varied geological environments to characterise formations based on their petrophsyical properties alone. Here, we discuss details of the specific algorithms chosen, size constraints and departures from standard commercially available packages. We present examples of results that use a variety of different petrophysical parameters; from spectral gamma ray logs used to independently assess lithology, to resisitivity and sonic logs used to identify the position of major boundaries. Examples of the methodology applied to subduction zone accretionary prism sediments (IODP Expedition 314), oceanic crustal rocks (e.g. ODP Hole 735B) and from continental shelf siliciclastic sediments (IODP Expedition 313) are illustrated.

  12. Used Fuel Management System Interface Analyses - 13578

    SciTech Connect

    Howard, Robert; Busch, Ingrid [Oak Ridge National Laboratory, P.O. Box 2008, Bldg. 5700, MS-6170, Oak Ridge, TN 37831 (United States)] [Oak Ridge National Laboratory, P.O. Box 2008, Bldg. 5700, MS-6170, Oak Ridge, TN 37831 (United States); Nutt, Mark; Morris, Edgar; Puig, Francesc [Argonne National Laboratory (United States)] [Argonne National Laboratory (United States); Carter, Joe; Delley, Alexcia; Rodwell, Phillip [Savannah River National Laboratory (United States)] [Savannah River National Laboratory (United States); Hardin, Ernest; Kalinina, Elena [Sandia National Laboratories (United States)] [Sandia National Laboratories (United States); Clark, Robert [U.S. Department of Energy (United States)] [U.S. Department of Energy (United States); Cotton, Thomas [Complex Systems Group (United States)] [Complex Systems Group (United States)

    2013-07-01

    Preliminary system-level analyses of the interfaces between at-reactor used fuel management, consolidated storage facilities, and disposal facilities, along with the development of supporting logistics simulation tools, have been initiated to provide the U.S. Department of Energy (DOE) and other stakeholders with information regarding the various alternatives for managing used nuclear fuel (UNF) generated by the current fleet of light water reactors operating in the United States. An important UNF management system interface consideration is the need for ultimate disposal of UNF assemblies contained in waste packages that are sized to be compatible with different geologic media. Thermal analyses indicate that waste package sizes for the geologic media under consideration by the Used Fuel Disposition Campaign may be significantly smaller than the canisters being used for on-site dry storage by the nuclear utilities. Therefore, at some point along the UNF disposition pathway, there could be a need to repackage fuel assemblies already loaded and being loaded into the dry storage canisters currently in use. The implications of where and when the packaging or repackaging of commercial UNF will occur are key questions being addressed in this evaluation. The analysis demonstrated that thermal considerations will have a major impact on the operation of the system and that acceptance priority, rates, and facility start dates have significant system implications. (authors)

  13. A first characterization of the quench detection system for ITER

    Microsoft Academic Search

    C. Marinucci; L. Bottura; S. Pourrahimi

    1995-01-01

    The purpose of this paper is to assess the expected response of conventional and non-conventional quench detection sensors proposed for the ITER coils, and to be tested in the QUELL experiment in SULTAN. The assessment is based on simulation of thermohydraulic transients in the ITER coils for various operating conditions, and a tentative definition of the transfer functions of each

  14. ITER HEAT REMOVAL SYSTEM SYSTEM & PROCESS CONTROL DESIGN

    E-print Network

    Raffray, A. René

    are installed. HRS is not so peculiar, but rather a conventional system with cooling tower as the final heat cooling system and in-vessel components (shield blanket, baffle and divertor) cooling systems. However the vacuum vessel cooling system has a safety role of providing the ultimate decay heat removal system ,when

  15. Enhanced iterative learning control for a piezoelectric actuator system using wavelet transform filtering

    Microsoft Academic Search

    Chiang-Ju Chien; Fu-Shin Lee; Jhen-Cheng Wang

    2007-01-01

    For trajectory tracking of a piezoelectric actuator system, an enhanced iterative learning control (ILC) scheme based on wavelet transform filtering (WTF) is proposed in this research. The enhanced ILC scheme incorporates a state compensation in the ILC formula. Combining state compensation with iterative learning, the scheme enhances tracking accuracies substantially, in comparison to the conventional D-type ILC and a proportional

  16. Iterated Function Systems With Overlaps And Self-Similar Measures

    E-print Network

    Rao, Hui

    the open set condition (OSC) Hut]. One of the advantages of the OSC is that the \\generic" points of the set with the shift operation in the symbolic space. Without the OSC, the iteration has overlaps

  17. ITER neutral beam system US conceptual design. Final vesion

    SciTech Connect

    Purgalis, P.

    1990-09-01

    In this document we present the US conceptual design of a neutral beam system for International Thermonuclear Experimental Reactor (ITER). The design incorporates a barium surface conversion D{sup {minus}} source feeding a linear array of accelerator channels. The system uses a dc accelerator with electrostatic quadrupoles for strong focusing. A high voltage power supply that is integrated with the accelerator is presented as an attractive option. A gas neutralizer is used and residual ions exiting the neutralizer are deflected to water-cooled dumps. Cryopanels are located at the accelerator exit to pump excess gas from the source and the neutralizer, and in the ion dump cavity to pump re-neutralized ions and neutralizer gas. All the above components are packaged in compact identical, independent modules which can be removed for remote maintenance. The neutral beam system delivers 75 MW of DO at 1.3 MeV, into three ports with a total of 9 modules arranged in stacks of three modules per port . To increase reliability each module is designed to deliver up to 10 MW; this allows eight modules operating at partial capacity to deliver the required power in the event one module is out of service, and provides 20% excess capacity to improve availability. Radiation protection is provided by shielding and by locating critical components in the source and accelerator 46.5 m from the torus centerline. Neutron shielding in the drift duct and neutralizer provides the added feature of limiting conductance and thus reducing gas flow to and from the torus.

  18. Iterative Methods for Systems' Solving - a C# approach

    E-print Network

    Chirilov, Claudiu

    2009-01-01

    This work wishes to support various mathematical issues concerning the iterative methods with the help of new programming languages. We consider a way to show how problems in math have an answer by using different academic resources and different thoughts. Here we treat methods like Gauss-Seidel's, Cramer's and Gauss-Jordan's.

  19. SLAVE: a genetic learning system based on an iterative approach

    Microsoft Academic Search

    A. Gonzblez; R. Perez

    1999-01-01

    SLAVE is an inductive learning algorithm that uses concepts based on fuzzy logic theory. This theory has been shown to be a useful representational tool for improving the understanding of the knowledge obtained from a human point of view. Furthermore, SLAVE uses an iterative approach for learning based on the use of a genetic algorithm (GA) as a search algorithm.

  20. Iterative Repair Planning for Spacecraft Operations Using the ASPEN System

    Microsoft Academic Search

    Gregg Rabideau; Russell Knight; Steve Chien; Alex Fukunaga; Anita Govindjee

    1999-01-01

    This paper describes the Automated Scheduling and Planning Environment (ASPEN). ASPEN encodes complex spacecraft knowledge of operabilit y constraints, flight rules, spacecraft hardware, scien ce experiments and operations procedures to allow for automated generation of low level spacecraft sequences. Using a technique called iterative repair, ASPEN classifies constraint violations (i.e., conflicts) and attempts to repair each by performing a planning

  1. El Paso Electric photovoltaic-system analyses

    SciTech Connect

    Not Available

    1982-05-01

    Four analyses were performed on the Newman Power Station PV system. Two were performed using the Photovoltaic Transient Analysis Program (PV-TAP) and two with the SOLCEL II code. The first was to determine the optimum tilt angle for the array and the sensitivity of the annual energy production to variation in tilt angle. The optimum tilt angle was found to be 28/sup 0/, and variations of 2/sup 0/ produce losses of only 0.06% in the annual energy production. The second analysis assesses the power loss due to cell-to-cell variations in short circuit current and the degree of improvement attainable by sorting cells and matching modules. Typical distributions on short circuit current can cause losses of about 9.5 to 11 percent in peak array power, and sorting cells into 4 bins prior to module assembly can reduce the losses to about 6 to 8 percent. Using modules from the same cell bins in building series strings can reduce the losses to about 4.5 to 6 percent. Results are nearly the same if the array is operated at a fixed votage. The third study quantifies the magnitude and frequency of occurrence of high cell temperatures due to reverse bias caused by shadowing, and it demonstrates that cell temperatures achieved in reverse bias are higher for cells with larger shunt resistance. The last study assesses the adequacy of transient protection devices on the dc power lines to transients produced by array switching and lightning. Large surge capacitors on the dc power line effectively limit voltage excursions at the array and at the control room due to lightning. Without insertion of series resistors, the current may be limited only by cable and switch impedances, and all elements could be severely stressed. (LEW)

  2. Thermo-mechanical analysis of ITER first mirrors and its use for the ITER equatorial visible/infrared wide angle viewing system optical designa)

    NASA Astrophysics Data System (ADS)

    Joanny, M.; Salasca, S.; Dapena, M.; Cantone, B.; Travčre, J. M.; Thellier, C.; Fermé, J. J.; Marot, L.; Buravand, O.; Perrollaz, G.; Zeile, C.

    2012-10-01

    ITER first mirrors (FMs), as the first components of most ITER optical diagnostics, will be exposed to high plasma radiation flux and neutron load. To reduce the FMs heating and optical surface deformation induced during ITER operation, the use of relevant materials and cooling system are foreseen. The calculations led on different materials and FMs designs and geometries (100 mm and 200 mm) show that the use of CuCrZr and TZM, and a complex integrated cooling system can limit efficiently the FMs heating and reduce their optical surface deformation under plasma radiation flux and neutron load. These investigations were used to evaluate, for the ITER equatorial port visible/infrared wide angle viewing system, the impact of the FMs properties change during operation on the instrument main optical performances. The results obtained are presented and discussed.

  3. 2-D Reflectometer Modeling for Optimizing the ITER Low-field Side Reflectometer System

    SciTech Connect

    Kramer, G.J.; Nazikian, R.; Valeo, E.J.; Budny, R.V.; Kessel, C.; Johnson, D.

    2005-09-02

    The response of a low-field side reflectometer system for ITER is simulated with a 2?D reflectometer code using a realistic plasma equilibrium. It is found that the reflected beam will often miss its launch point by as much as 40 cm and that a vertical array of receiving antennas is essential in order to observe a reflection on the low-field side of ITER.

  4. A reduced complexity iterative non-coherent CPM detector for frequency hopped wireless military communication systems

    Microsoft Academic Search

    C. Brown; P. J. Vigneron

    2005-01-01

    An iterative symbol-by-symbol non-coherent detection scheme using serially concatenated continuous phase modulation for application in wireless, frequency hopping, military communication systems is presented. The scheme exploits an iterative tree search algorithm in the detector, to reduce the overall complexity of the receiver, whilst maintaining a BER performance within 0.5 dB compared to detectors employing exhaustive tree search techniques. In addition,

  5. An Iterative Numerical Algorithm for a Strongly Coupled System of Singularly Perturbed Convection-Diffusion Problems

    Microsoft Academic Search

    E. O’Riordan; J. Stynes; M. Stynes

    2008-01-01

    An iterative numerical method is constructed for a coupled system of singularly perturbed convection-diffusion-reaction two-point\\u000a boundary value problems. It combines a standard finite difference operator with a piecewise-uniform Shishkin mesh, and uses\\u000a a Jacobi-type iteration to compute a solution. Under certain assumptions on the coefficients in the differential equations,\\u000a a bound on the maximum-norm error in the computed solution is

  6. Energy Saving Control in Air Conditioning System Based on Flexible Iterative Learning Control

    Microsoft Academic Search

    Zuojun Liu; Chuang Cao; Peng Yang; Ying Zhou

    2008-01-01

    According to the repetition and periodicity of air conditioning system, a method of flexible iterative learning control based on the historical data is proposed and applied into the air conditioning system. The air conditioning system is repetitive and periodic with finite operation intervals, but there are some irregular uncertain factors, such as dynamic climate and other disturbances, so a flexible

  7. Iterative higher order sliding mode observer for nonlinear systems with unknown inputs

    E-print Network

    Paris-Sud XI, Université de

    Iterative higher order sliding mode observer for nonlinear systems with unknown inputs Jean of the design sliding mode ob- servers for nonlinear systems subject to unknown inputs. In most ap- proaches into a specific canonical observable form. Then, the state and the unknown input of the system can be recov- ered

  8. Iterative Integer Programming Formuation for Robust Resource Allocation in Dynamic Real-Time Systems

    Microsoft Academic Search

    Sethavidh Gertphol; Viktor K. Prasanna

    2004-01-01

    Summary form only given. Dynamic real-time systems often operate in a continuously changing environment, causing workload of the system to fluctuate. An initial resource allocation for these systems should be robust with respect to the variation in workload. Using the amount of additional workload that an allocation can accommodate as a measure of robustness, we develop an iterative integer programming

  9. A comparison of iterative methods for a model coupled system of elliptic equations

    SciTech Connect

    Donato, J.M.

    1993-08-01

    Many interesting areas of current industry work deal with non-linear coupled systems of partial differential equations. We examine iterative methods for the solution of a model two-dimensional coupled system based on a linearized form of the two carrier drift-diffusion equations from semiconductor modeling. Discretizing this model system yields a large non-symmetric indefinite sparse matrix. To solve the model system various point and block methods, including the hybrid iterative method Alternate Block Factorization (ABF), are applied. We also employ GMRES with various preconditioners, including block and point incomplete LU (ILU) factorizations. The performance of these methods is compared. It is seen that the preferred ordering of the grid variables and the choice of iterative method are dependent upon the magnitudes of the coupling parameters. For this model, ABF is the most robust of the non-accelerated iterative methods. Among the preconditioners employed with GMRES, the blocked ``by grid point`` version of both the ILU and MILU preconditioners are the most robust and the most time efficient over the wide range of parameter values tested. This information may aid in the choice of iterative methods and preconditioners for solving more complicated, yet analogous, coupled systems.

  10. Optimal codesign of nonlinear control systems based on a modified policy iteration method.

    PubMed

    Jiang, Yu; Wang, Yebin; Bortoff, Scott A; Jiang, Zhong-Ping

    2015-02-01

    This brief studies the optimal codesign of nonlinear control systems: simultaneous design of physical plants and related optimal control policies. Nonlinearity of the optimal codesign problem could come from either a nonquadratic cost function or the plant. After formulating the optimal codesign into a nonconvex optimization problem, an iterative scheme is proposed in this brief by adding an additional step of system-equivalence-based policy improvement to the conventional policy iteration. We have proved rigorously that the closed-loop system performance can be improved after each step of the proposed policy iteration scheme, and the convergence to a suboptimal solution is guaranteed. It is also shown that under certain conditions, this additional policy improvement step can be conducted by solving a quadratic programming problem. The linear version of the proposed methodology is addressed in the context of linear quadratic regulator. Finally, the effectiveness of the proposed methodology is illustrated through the optimal codesign of a load-positioning system. PMID:25576583

  11. Informing the design of an information management system with iterative fieldwork

    Microsoft Academic Search

    Victoria Bellotti; Ian Smith

    2000-01-01

    We report on the design process of a personal information management system, Raton Laveur, and how it was influenced by an intimate relationship between iterative fieldwork and design thinking. Initially, the system was conceived as a paper-based UI to calendar, contacts, to-dos and notes. As the fieldwork progressed, our understanding of peoples practices and the constraints of their office infrastructures

  12. InterIntra Molecular Dynamics as an Iterated Function System Kunihiko KANEKO

    E-print Network

    Kaneko, Kunihiko

    Inter­Intra Molecular Dynamics as an Iterated Function System Kunihiko KANEKO Department of Basic function system, Cantor set, inter­intra molecular dynamics DOI: 10.1143/JPSJ.74.2386 Biological units have novel dynamical states that are not expected when considering only single molecular dynamics (see also

  13. Results of Iterative Standards-Setting Procedures for a Performance-Based System for Renewable Certification.

    ERIC Educational Resources Information Center

    Lofton, Glenda G.; And Others

    This report presents the results of an initial, iterative performance standards-setting (SS) task of a comprehensive on-the-job statewide teacher assessment system--the System for Teaching and Learning Assessment and Review (STAR). The 1990-91 STAR assesses and makes inferences about the quality of teaching and learning on sets of assessment…

  14. Studies on the radio frequency power supply system for the ITER NB injector ion source

    Microsoft Academic Search

    E. Gaio; W. Kraus; C. Martens; R. Piovan; E. Speth; V. Toigo

    2007-01-01

    In the framework of the European activities on the ITER neutral beam (NB) injector, the design of a 1MHz, 1MW power supply (PS) system for the radio frequency (RF) driven ion source, has been developed in cooperation between IPP and RFX laboratories. This paper describes the studies performed with particular emphasis on the system design, the definition of the best

  15. Iterative learning control for singularly perturbed systems Konstantin E. Avrachenkov 1 Anatoly A. Pervozvanski 2

    E-print Network

    Avrachenkov, Konstantin

    Iterative learning control for singularly perturbed systems Konstantin E. Avrachenkov 1 Anatoly A. Pervozvanski 2 Abstract The singularly perturbed systems are described by dif­ ferential equations with a small diverge in the presence of singular perturbations. The aim of the present pa­ per is to construct learning

  16. Research on an Iterative Algorithm of LS Channel Estimation in MIMO OFDM Systems

    Microsoft Academic Search

    Yantao Qiao; Songyu Yu; Pengcheng Su; Lijun Zhang

    2005-01-01

    An iterative Least Square (LS) channel estimation algorithm for MIMO OFDM systems was proposed in this paper. Compared to common LS channel estimation, this algorithm can greatly improve estimation accuracy, and the low-pass filtering in time domain reduces AWGN and ICI significantly. MIMO OFDM system with this algorithm also works well in mobile situations. Simulation results have shown good MSE

  17. Progress in the Integrated Simulation of Thermal-Hydraulic Operation of the ITER Magnet System

    E-print Network

    Bagnasco, M; Bessette, D; Marinucci, C

    2010-01-01

    A new integrated computer code is being developed for the simulations of the overall behavior of the ITER magnet cryo-system. The existing THEA, FLOWER and POWER codes, assembled as modules of a computational environment (Super-Magnet) have been upgraded to perform global simulations of the cooling circuit for the ITER magnet system. The thermal coupling resulting from the generic geometric configurations has been implemented to realize quasi-three-dimensional simulations of the winding pack. In this paper we present details on the model.

  18. An iterative aggregation and disaggregation method for the steady state solution of large scale continuous systems

    NASA Astrophysics Data System (ADS)

    Biswas, Katja

    2015-06-01

    Iterative aggregation and disaggregation (IAD) methods are a class of iterative methods which allow the fast calculation of the eigenvector corresponding to the unit eigenvalue of large stochastic matrices. This makes them particularly appealing to use in high resolution studies of large continuous systems. In this paper it is shown how an IAD matrix method with pre- and post-smoothing steps can be used to obtain the steady state probability distribution of large scale continuous systems. The method is illustrated in two numerical examples of overdamped Brownian motion processes subject to external potentials.

  19. Total-system performance assessment for Yucca Mountain -- SNL second iteration (TSPA-1993); Executive summary

    SciTech Connect

    Wilson, M.L.; Barnard, R.W. [Sandia National Labs., Albuquerque, NM (United States); Gauthier, J.H. [Sandia National Labs., Albuquerque, NM (United States)]|[Spectra Research, Inc. (United States)] [and others

    1994-04-01

    Sandia National Laboratories has completed the second iteration of the periodic total-system performance assessments (TSPA-93) for the Yucca Mountain Site Characterization Project (YMP). Scenarios describing expected conditions (aqueous and gaseous transport of contaminants) and low-probability events (human-intrusion drilling and volcanic intrusion) are modeled. The hydrologic processes modeled include estimates of the perturbations to ambient conditions caused by heating of the repository resulting from radioactive decay of the waste. TSPA-93 incorporates significant new detailed process modeling, including two- and three-dimensional modeling of thermal effects, groundwater flow in the saturated-zone aquifers, and gas flow in the unsaturated zone. Probabilistic analyses are performed for aqueous and gaseous flow and transport, human intrusion, and basaltic magmatic activity. Results of the calculations lead to a number of recommendations concerning studies related to site characterization. Primary among these are the recommendations to obtain better information on percolation flux at Yucca Mountain, on the presence or absence of flowing fractures, and on physical and chemical processes influencing gaseous flow. Near-field thermal and chemical processes, and waste-container degradation are also areas where additional investigations may reduce important uncertainties. Recommendations for repository and waste-package design studies are: (1) to evaluate the performance implications of large-size containers, and (2) to investigate in more detail the implications of high repository thermal power output on the adjacent host rock and on the spent fuel.

  20. Advances in Thermogravimetric Analyses of Elastomer Systems

    Microsoft Academic Search

    John J. Maurer

    1974-01-01

    Practical rubber formulations are complex mixtures of polymer (s), fillers, plasticizers, curatives, and processing aids. Classical methods exist for determining many of the components of these systems but are too time consuming for routine use in quality control or problem solving activities. Thus a need has existed for more rapid procedures. Previous studies of gum, compounded, and cured elastomers showed

  1. ANALYSING RADIATION TRANSPORT THROUGH COMPLEX FENESTRATION SYSTEMS

    Microsoft Academic Search

    N. S. Campbell; J. K. Whittle

    This paper briefly reviews recent research into the modelling of complex fenestration systems, before presenting some results obtained by the use of a new (developing) simulation model, utilising Monte Carlo Methods and Geometric Optics (ray tracing). In particular, the distribution of (solar) radiation by windows containing (interstitial) venetian blinds is examined, since they continue to represent conventional window management practice,

  2. Systems Analyses of Advanced Brayton Cycles

    SciTech Connect

    A.D. Rao; D.J. Francuz; J.D. Maclay; J. Brouwer; A. Verma; M. Li; G.S. Samuelsen

    2008-09-30

    The main objective is to identify and assess advanced improvements to the Brayton Cycle (such as but not limited to firing temperature, pressure ratio, combustion techniques, intercooling, fuel or combustion air augmentation, enhanced blade cooling schemes) that will lead to significant performance improvements in coal based power systems. This assessment is conducted in the context of conceptual design studies (systems studies) that advance state-of-art Brayton cycles and result in coal based efficiencies equivalent to 65% + on natural gas basis (LHV), or approximately an 8% reduction in heat rate of an IGCC plant utilizing the H class steam cooled gas turbine. H class gas turbines are commercially offered by General Electric and Mitsubishi for natural gas based combined cycle applications with 60% efficiency (LHV) and it is expected that such machine will be offered for syngas applications within the next 10 years. The studies are being sufficiently detailed so that third parties will be able to validate portions or all of the studies. The designs and system studies are based on plants for near zero emissions (including CO{sub 2}). Also included in this program is the performance evaluation of other advanced technologies such as advanced compression concepts and the fuel cell based combined cycle. The objective of the fuel cell based combined cycle task is to identify the desired performance characteristics and design basis for a gas turbine that will be integrated with an SOFC in Integrated Gasification Fuel Cell (IGFC) applications. The goal is the conceptualization of near zero emission (including CO{sub 2} capture) integrated gasification power plants producing electricity as the principle product. The capability of such plants to coproduce H{sub 2} is qualitatively addressed. Since a total systems solution is critical to establishing a plant configuration worthy of a comprehensive market interest, a baseline IGCC plant scheme is developed and used to study how alternative process schemes and power cycles might be used and integrated to achieve higher systems efficiency. To achieve these design results, the total systems approach is taken requiring creative integration of the various process units within the plant. Advanced gas turbine based cycles for Integrated gasification Combined cycle (IGCC) applications are identified by a screening analysis and the more promising cycles recommended for detailed systems analysis. In the case of the IGFC task, the main objective is met by developing a steady-state simulation of the entire plant and then using dynamic simulations of the hybrid Solid Oxide Fuel Cell (SOFC)/Gas Turbine sub-system to investigate the turbo-machinery performance. From these investigations the desired performance characteristics and a basis for design of turbo-machinery for use in a fuel cell gas turbine power block is developed.

  3. Analysing Lyapunov spectra of chaotic dynamical systems

    E-print Network

    Fotis Diakonos; Detlef Pingel; Peter Schmelcher

    2000-06-07

    It is shown that the asymptotic spectra of finite-time Lyapunov exponents of a variety of fully chaotic dynamical systems can be understood in terms of a statistical analysis. Using random matrix theory we derive numerical and in particular analytical results which provide insights into the overall behaviour of the Lyapunov exponents particularly for strange attractors. The corresponding distributions for the unstable periodic orbits are investigated for comparison.

  4. Iterative receivers for OFDM systems with dispersive fading and frequency offset

    E-print Network

    Liu, Hui

    2004-09-30

    . : : : : : : : : : : : : 13 9 A coded OFDM system with iterative receiver. : : : : : : : : : : : : 16 10 BER in a coded OFDM system through a 4-tap frequency selective fading channel with Doppler shift fd = 50Hz. Carrier frequency o set f = 0:05=N.... : : : : : : : : : : : : : : : : : : : : : : : : : : : : 25 11 BER in a coded OFDM system through a 4-tap frequency selective fading channel with Doppler shift fd = 50Hz. Carrier frequency o set f = 0:1=N. : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 26 12 BER in a coded OFDM system through a...

  5. A Lower Hybrid Current Drive System for ITER and High Power CW Klystron Development

    NASA Astrophysics Data System (ADS)

    Hoang, G. T.; Bécoulet, A.; Artaud, J. F.; Berger-By, G.; Decker, J.; Delpech, L.; Ekedahl, A.; Garcia, J.; Giruzzi, G.; Goniche, M.; Guilhem, D.; Hillairet, J.; Imbeaux, F.; Litaudon, X.; Magne, R.; Peysson, Y.; Schneider, M.; Jacquinot, J.; Bae, Y. S.; Beaumont, B.; Belo, J. H.; Bizarro, J. P. S.; Bonoli, P.; Cho, M. H.; Kazarian, F.; Kessel, C.; Kim, S. H.; Kwak, J. G.; Jeong, J. H.; Lister, J. B.; Milora, S.; Mirizzi, F.; Maggiora, R.; Milanesio, D.; Namkung, W.; Noterdaeme, J. M.; Park, S. I.; Parker, R.; Rasmussen, D.; Sharma, P. K.; Tanga, A.; Tuccillo, A.; Wan, Y. X.

    2009-11-01

    A 20 MW/5 GHz Lower Hybrid Current Drive (LHCD) system was initially due to be commissioned and used for the second mission of ITER, i.e. the Q = 5 steady state target. Though not part of currently planned procurement phase, it is now under consideration for an earlier delivery. An LH program has been initiated under EFDA, following the ITER STAC recommendation, to provide a pre-design document including the conceptual design, costing, possible procurement allocation, WBS and R&D needs.

  6. Tracking control of nonlinear lumped mechanical continuous-time systems: A model-based iterative learning approach

    Microsoft Academic Search

    K. Smolders; M. Volckaert; J. Swevers

    2008-01-01

    This paper presents a nonlinear model-based iterative learning control procedure to achieve accurate tracking control for nonlinear lumped mechanical continuous-time systems. The model structure used in this iterative learning control procedure is new and combines a linear state space model and a nonlinear feature space transformation. An intuitive two-step iterative algorithm to identify the model parameters is presented. It alternates

  7. An iterative inter-track interference mitigation method for two-dimensional magnetic recording systems

    NASA Astrophysics Data System (ADS)

    Warisarn, C.; Losuwan, T.; Supnithi, P.; Kovintavewat, P.

    2014-05-01

    At high recording density, the readback signal of two-dimensional magnetic recording is inevitably corrupted by the two-dimensional (2D) interference consisting of inter-symbol interference and inter-track interference (ITI), which can significantly degrade the overall system performance. This paper proposes an iterative ITI mitigation method using three modified 2D soft-output Viterbi algorithm (2D-SOVA) detectors in conjunction with an iterative processing technique to combat the 2D interference. The codeword of the outer code is divided and then written on three separate tracks. For every iteration, all 2D-SOVA detectors exchange the soft information to improve the reliability of the a priori information and use it in the branch metric calculation, before feeding the refined soft information to the outer decoder. Simulation results show that the proposed method outperforms the conventional receiver and the existing partial ITI mitigation method.

  8. A coherent FM laser radar based system for remote metrology in ITER

    Microsoft Academic Search

    R. E. Barry; T. W. Burgess; M. M. Menon; A. Slotwinski; R. Sebastian

    1995-01-01

    The plasma facing surfaces in ITER must be aligned to millimeter accuracy with respect to the magnetic flux surfaces to prevent impurity influx into the plasma and to avoid component damage. Checking of in-vessel component alignment during initial assembly, operation, and subsequent maintenance is anticipated. A fully remote metrology system is necessary, particularly since major remote operations such as shield

  9. Monotonically convergent iterative learning control for linear discrete-time systems

    Microsoft Academic Search

    Kevin L. Moore; Yangquan Chen; Vikas Bahl

    2005-01-01

    In iterative learning control schemes for linear discrete time systems, conditions to guarantee the monotonic convergence of the tracking 9 error norms are derived. By using the Markov parameters, it is shown in the time-domain that there exists a non-increasing function such that when the properly chosen constant learning gain is multiplied by this function, the convergence of the tracking

  10. Passivity based iterative learning control for mechanical systems subject to dry friction

    Microsoft Academic Search

    Rafael Quintanilla; John T. Wen

    2008-01-01

    This paper considers iterative learning control applied to a mass-damper system subject to dry friction. The dry friction nonlinearity is discontinuous, and therefore poses challenges to the conventional learning control methods. We apply the passivity based analysis in learning control and show that it is applicable to the case with velocity output. In the case of combined position and velocity

  11. An Iterative Algorithm for Partitioning and Scheduling of Area Constrained HW-SW Systems

    E-print Network

    Chatha, Karam S.

    An Iterative Algorithm for Partitioning and Scheduling of Area Constrained HW-SW Systems Karam S- cessors and customhardware units. Hardware-software HW-SW codesign process takes an application spec- i- ture. Our paper presents a technique for HW-SW par- titioningand scheduling ofthe applicationspeci

  12. Sampled-data Iterative Learning Control for a Class of Nonlinear Networked Control Systems

    E-print Network

    Marquez, Horacio J.

    in a fixed finite interval. In the networked control systems (NCS), because of the existence of time delays error tends to be zero as the number of iteration increases. Furthermore, the convergence diagnosis and maintenance, and higher reliability. In NCS, one feature is that the control loops are closed

  13. APPLICATION OF THE VARIATIONAL ITERATION METHOD FOR SYSTEM OF NONLINEAR VOLTERRA'S INTEGRO-DIFFERENTIAL EQUATIONS

    Microsoft Academic Search

    Saeid Abbasbandy

    In this paper, the variational iteration method is proposed to solve system of nonlinear Volterra's integro-differential equations. Four numerical examples are illustrated by this method. The results reveal that this method is very effective and highly promising in comparison with other numerical methods.

  14. On Modified Newton Iterations for SPARK Methods Applied to Constrained Systems in Mechanics

    NASA Astrophysics Data System (ADS)

    Jay, Laurent O.

    2009-09-01

    The application of modified Newton iterations to the solution of SPARK methods applied to a large class of overdetermined differential-algebraic equations (ODAEs) is described in some details. These ODAEs include the formulation of systems in mechanics with holonomic and nonholonomic constraints.

  15. ANALYSING SECURITY REQUIREMENTS OF INFORMATION SYSTEMS USING TROPOS

    E-print Network

    ANALYSING SECURITY REQUIREMENTS OF INFORMATION SYSTEMS USING TROPOS Keywords: Information Systems in integrating security concerns during the analysis of information systems. Current methodologies fail of Tropos. The above is illustrated using an agent-based health and social care information system as a case

  16. Mechanical behavior of the ITER TF model coil ground insulation system after reactor irradiation

    NASA Astrophysics Data System (ADS)

    Bittner-Rohrhofer, K.; Humer, K.; Fillunger, H.; Maix, R. K.; Weber, H. W.

    2002-11-01

    The mechanical properties of glass fiber reinforced plastics (GFRPs) suggested for the turn and ground insulation of the ITER toroidal field (TF) coils are subject to extensive investigations with respect to their design requirements at present. The insulation system used for the ITER TF model coil, manufactured by European industry, consists of a boron-free R-glass fiber reinforced tape, vacuum-pressure impregnated in a DGEBA epoxy system and partly interleaved with polyimide-foils (e.g. Kapton-H-foils). In order to assess the material performance under the actual operating conditions of ITER-FEAT, the system was irradiated in the TRIGA reactor (Vienna, Austria) to neutron fluences of 5×10 21 and 1×10 22 m -2 ( E>0.1 MeV). The composite was screened at 77 K using static tensile, short-beam-shear (SBS) as well as double-lap-shear tests prior to and after irradiation. Furthermore, tension-tension fatigue measurements were done in order to simulate the pulsed ITER-FEAT operation. We observe that the mechanical strength and the fracture behavior of these GFRPs after irradiation are strongly influenced by the three factors: the winding direction of the tape, the quality of fabrication and the delamination process.

  17. An iteration method for calculating the periodic solution of time-delay systems after a Hopf bifurcation

    Microsoft Academic Search

    Z. H. Wang

    2008-01-01

    A general description of the iteration method is presented in this paper for calculating the periodic solution resulted from\\u000a a Hopf bifurcation of time-delay systems including the degenerated cases (the delays disappear): ordinary differential equations.\\u000a Two algorithms are developed for scalar systems and for general systems, respectively. For scalar systems, the iteration method\\u000a is straightforward, and for general systems, the

  18. An Iterative Power Allocation Scheme for Spread Spectrum Wireless Systems

    E-print Network

    Chronopoulos, Anthony T.

    optimization problem for direct-sequence spread spectrum systems by considering the joint transmitted power-power radios. I. INTRODUCTION In direct-sequence spread spectrum (DSSS) systems, ra- dio channel is normally

  19. Cryogenic Viscous Compressor Development and Modeling for the ITER Vacuum System

    SciTech Connect

    Baylor, Larry R [ORNL; Meitner, Steven J [ORNL; Barbier, Charlotte N [ORNL; Combs, Stephen Kirk [ORNL; Duckworth, Robert C [ORNL; Edgemon, Timothy D [ORNL; Rasmussen, David A [ORNL; Hechler, Michael P [ORNL; Kersevan, R. [ITER Organization, Cadarache, France; Dremel, M. [General Atomics, San Diego; Pearce, R.J.H. [General Atomics, San Diego; Boissin, Jean Claude [Consultant

    2011-01-01

    The ITER vacuum system requires a roughing pump system that can pump the exhaust gas from the torus cryopumps to the tritium exhaust processing plant. The gas will have a high tritium content and therefore conventional vacuum pumps are not suitable. A pump called a cryogenic viscous compressor (CVC) is being designed for the roughing system to pump from ~500 Pa to 10 Pa at flow rates of 200 Pa-m3/ s. A unique feature of this pump is that is allows any helium in the gas to flow through the pump where it is sent to the detritiation system before exhausting to atmosphere. A small scale prototype of the CVC is being tested for heat transfer characteristics and compared to modeling results to ensure reliable operation of the full scale CVC. Keywords- ITER; vacuum; fuel cycle

  20. Development of equatorial visible\\/infrared wide angle viewing system and radial neutron camera for ITER

    Microsoft Academic Search

    Sophie Salasca; Basilio Esposito; Yann Corre; Maryline Davi; Christian Dechelle; Florian Pasdeloup; Roger Reichle; Jean-Marcel Travčre; Giorgio Brolatti; Daniele Marocco; Fabio Moro; Luigino Petrizzi; Tonio Pinna; Marco Riva; Rosaria Villari; Eduardo De La Cal; Carlos Hidalgo; Ana Manzanares; Jose Luis De Pablos; Rafael Vila; Gabor Hordosy; Daniel Nagy; Sandor Recsei; Szilveszter Tulipan; Andre Neto; Carlos Silva; Luciano Bertalot; Chris Walker; Christian Ingesson; Yuri Kaschuck

    2009-01-01

    The exploitation of ITER tokamak will require diagnostics for machine protection, inputs to plasma control systems, evaluation and analysis of plasma parameters and performances.The equatorial visible\\/infrared wide angle viewing system and the radial neutron camera are the two main diagnostics of Procurement Package 11 (PP11), one of the diagnostic procurements under the responsibility of Europe, which also contains Equatorial Port

  1. Dynamics analyses of space power systems using the salt code

    SciTech Connect

    Geyer, H.K.; Bhattacharyya, S.K.; Hanan, N.A.; Livingston, J.M. (Argonne National Lab., IL (USA); Westinghouse Electric Corp., Pittsburgh, PA (USA))

    1989-01-01

    The dynamic behavior of large space power systems has been identified as a significant technical issue. To date several analyses of reactor kinetics have been reported in the literature, but there have been few (if any) studies of the dynamic response of the entire space power system. The problem is complex and required analytical methods are not generally available. Furthermore, given the conceptual state of current MMW space power systems designs, dynamic models of components are not generally available. We have used the SALT code to perform preliminary analyses of the startup and shutdown transients of several proposed MMW system designs. In this paper we will provide a description of the code methodology and present results of the analyses performed for the NERVA derivative reactor (NDR) system. 3 refs., 3 figs.

  2. Total-system performance assessment for Yucca Mountain - SNL second iteration (TSPA-1993); Volume 2

    SciTech Connect

    Wilson, M.L.; Barnard, R.W.; Barr, G.E.; Dockery, H.A.; Dunn, E.; Eaton, R.R.; Martinez, M.J. [Sandia National Labs., Albuquerque, NM (United States); Gauthier, J.H.; Guerin, D.C.; Lu, N. [and others

    1994-04-01

    Sandia National Laboratories has completed the second iteration of the periodic total-system performance assessments (TSPA-93) for the Yucca Mountain Site Characterization Project (YMP). These analyses estimate the future behavior of a potential repository for high-level nuclear waste at the Yucca Mountain, Nevada, site under consideration by the Department of Energy. TSPA-93 builds upon previous efforts by emphasizing YMP concerns relating to site characterization, design, and regulatory compliance. Scenarios describing expected conditions (aqueous and gaseous transport of contaminants) and low-probability events (human-intrusion drilling and volcanic intrusion) are modeled. The hydrologic processes modeled include estimates of the perturbations to ambient conditions caused by heating of the repository resulting from radioactive decay of the waste. Hydrologic parameters and parameter probability distributions have been derived from available site data. Possible future climate changes are modeled by considering two separate groundwater infiltration conditions: {open_quotes}wet{close_quotes} with a mean flux of 10 mm/yr, and {open_quotes}dry{close_quotes} with a mean flux of 0.5 mm/yr. Two alternative waste-package designs and two alternative repository areal thermal power densities are investigated. One waste package is a thin-wall container emplaced in a vertical borehole, and the second is a container designed with corrosion-resistant and corrosion-allowance walls emplaced horizontally in the drift. Thermal power loadings of 57 kW/acre (the loading specified in the original repository conceptual design) and 114 kW/acre (a loading chosen to investigate effects of a {open_quotes}hot repository{close_quotes}) are considered. TSPA-93 incorporates significant new detailed process modeling, including two- and three-dimensional modeling of thermal effects, groundwater flow in the saturated-zone aquifers, and gas flow in the unsaturated zone.

  3. Harmonic analysis of iterated function systems with overlap

    E-print Network

    Palle E. T. Jorgensen; Keri A. Kornelson; Karen L. Shuman

    2007-01-27

    In this paper we extend previous work on IFSs without overlap. Our method involves systems of operators generalizing the more familiar Cuntz relations from operator algebra theory, and from subband filter operators in signal processing.

  4. A laser scanning system for metrology and viewing in ITER

    SciTech Connect

    Spampinato, P.T.; Barry, R.E.; Menon, M.M.; Herndon, J.N. [Oak Ridge National Lab., TN (United States); Dagher, M.A.; Maslakowski, J.E. [Rockwell Rocketdyne Div., Canoga Park, CA (United States)

    1996-05-01

    The construction and operation of a next-generation fusion reactor will require metrology to achieve and verify precise alignment of plasma-facing components and inspection in the reactor vessel. The system must be compatible with the vessel environment of high gamma radiation (10{sup 4} Gy/h), ultra-high-vacuum (10{sup {minus}8} torr), and elevated temperature (200 C). The high radiation requires that the system be remotely deployed. A coherent frequency modulated laser radar-based system will be integrated with a remotely operated deployment mechanism to meet these requirements. The metrology/viewing system consists of a compact laser transceiver optics module which is linked through fiber optics to the laser source and imaging units that are located outside of a biological shield. The deployment mechanism will be a mast-like positioning system. Radiation-damage tests will be conducted on critical sensor components at Oak Ridge National Laboratory to determine threshold damage levels and effects on data transmission. This paper identifies the requirements for International Thermonuclear Experimental Reactor metrology and viewing and describes a remotely operated precision ranging and surface mapping system.

  5. Models Extracted from Text for System-Software Safety Analyses

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.

    2010-01-01

    This presentation describes extraction and integration of requirements information and safety information in visualizations to support early review of completeness, correctness, and consistency of lengthy and diverse system safety analyses. Software tools have been developed and extended to perform the following tasks: 1) extract model parts and safety information from text in interface requirements documents, failure modes and effects analyses and hazard reports; 2) map and integrate the information to develop system architecture models and visualizations for safety analysts; and 3) provide model output to support virtual system integration testing. This presentation illustrates the methods and products with a rocket motor initiation case.

  6. A parallel iterative partitioned coupling analysis system for large-scale acoustic fluid-structure interactions

    NASA Astrophysics Data System (ADS)

    Kataoka, Shunji; Minami, Satsuki; Kawai, Hiroshi; Yamada, Tomonori; Yoshimura, Shinobu

    2014-06-01

    In many engineering fields, dynamic response in fluid-structure interaction (FSI) is important, and some of the FSI phenomena are treated as acoustic FSI (AFSI) problems. Dynamic interactions between fluids and structures may change dynamic characteristics of the structure and its response to external excitation parameters such as seismic loading. This paper describes a parallel coupling analysis system for large-scale AFSI problems using iterative partitioned coupling techniques. We employ an open source parallel finite element analysis system called ADVENTURE, which adopts an efficient preconditioned iterative linear algebraic solver. In addition, we have recently developed a parallel coupling tool called ADVENTURE_Coupler to efficiently handle interface variables in various parallel computing environments. We also employ the Broyden method for updating interface variables to attain robust and fast convergence of fixed-point iterations. This paper describes key features of the coupling analysis system developed, and we perform tests to validate its performance for several AFSI problems. The system runs efficiently in a parallel environment, and it is capable of analyzing three-dimensional-complex-shaped structures with more than 20 million degrees-of-freedom (DOFs). Its numerical results also show good agreement with experimental results.

  7. Spatial Views : Iterative Spatial Programming for Networks of Embedded Systems #

    E-print Network

    Kremer, Ulrich

    Abstract Programming a large network of embedded systems (NES) is an enormous challenge since all for spatially distributed network resources. In Spatial Programming, NES applications appear as simple sequential programs using spatial variables. However, for many NES applications the spatial programming model

  8. Iterative Least Squares Channel Estimation in Frequency Selective CDMA Systems

    Microsoft Academic Search

    Ahmet Rizaner; Hasan Amca; Ali H. Ulusoy; Kadri Hacioglu

    2006-01-01

    Multiple access interference (MAI) is the main factor affecting the performance of channel estimation techniques for code division multiple access (CDMA) systems. Although, several multi-user channel estimation algorithms have been proposed to mitigate MAI, these algorithms require high computational complexities. In this paper, we address the problem of least squares (LS) mobile channel estimation at high channel efficiency that requires

  9. Design of the RTO\\/RC ITER primary pumping system

    Microsoft Academic Search

    P Ladd; C Ibbott; G Janeschitz; E Martin

    2000-01-01

    The primary pumping system is needed not only to exhaust helium ash resulting from the DT reaction but also excess fuelling gas injected during the fusion burn, which can extend for 100's to 1000's of seconds, and to perform a variety of other functions. The prevailing environmental conditions, principally nuclear radiation, tritium exposure, magnetic fields, and the need for containment,

  10. Tritium processing system for the ITER Li/V blanket test module

    SciTech Connect

    Sze, D.K.; Hua, T.Q. [Argonne National Lab., IL (United States); Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Dagher, M.A.; Waganer, L.M.

    1997-04-01

    The purpose of the ITER Blanket Testing Module is to test the operating and performance of candidate blanket concepts under a real fusion environment. To assure fuel self-sufficiency the tritium breeding, recovery and processing have to be demonstrated. The tritium produced in the blanket has to be processed to a purity which can be used for refueling. All these functions need to be accomplished so that the tritium system can be scaled to a commercial fusion power plant from a safety and reliability point of view. This paper summarizes the tritium processing steps, the size of the equipment, power requirements, space requirements, etc. for a self-cooled lithium blanket. This information is needed for the design and layout of the test blanket ancillary system and to assure that the ITER guidelines for remote handling of ancillary equipment can be met.

  11. ITER helium ash accumulation

    SciTech Connect

    Hogan, J.T.; Hillis, D.L.; Galambos, J.; Uckan, N.A. (Oak Ridge National Lab., TN (USA)); Dippel, K.H.; Finken, K.H. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Plasmaphysik); Hulse, R.A.; Budny, R.V. (Princeton Univ., NJ (USA). Plasma Physics Lab.)

    1990-01-01

    Many studies have shown the importance of the ratio {upsilon}{sub He}/{upsilon}{sub E} in determining the level of He ash accumulation in future reactor systems. Results of the first tokamak He removal experiments have been analysed, and a first estimate of the ratio {upsilon}{sub He}/{upsilon}{sub E} to be expected for future reactor systems has been made. The experiments were carried out for neutral beam heated plasmas in the TEXTOR tokamak, at KFA/Julich. Helium was injected both as a short puff and continuously, and subsequently extracted with the Advanced Limiter Test-II pump limiter. The rate at which the He density decays has been determined with absolutely calibrated charge exchange spectroscopy, and compared with theoretical models, using the Multiple Impurity Species Transport (MIST) code. An analysis of energy confinement has been made with PPPL TRANSP code, to distinguish beam from thermal confinement, especially for low density cases. The ALT-II pump limiter system is found to exhaust the He with maximum exhaust efficiency (8 pumps) of {approximately}8%. We find 1<{upsilon}{sub He}/{upsilon}{sub E}<3.3 for the database of cases analysed to date. Analysis with the ITER TETRA systems code shows that these values would be adequate to achieve the required He concentration with the present ITER divertor He extraction system.

  12. Materials issues in diagnostic systems for BPX and ITER

    SciTech Connect

    Clinard, F.W. Jr.; Farnum, E.H. (Los Alamos National Lab., NM (United States)); Griscom, D.L. (Naval Research Lab., Washington, DC (United States)); Mattas, R.F. (Argonne National Lab., IL (United States)); Medley, S.S.; Young, K. M. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Wiffen, F.W. (USDOE, Washington, DC (United States)); Wojtowicz, S.S. (General Atomics, San Diego, CA (Unit

    1991-01-01

    Diagnostic systems in advanced D-T-burning fusion devices will be subjected to intense fluxes and fluences of high-energy neutrons and gamma rays. Materials used in these systems may suffer significant degradation of structural, optical, and electrical properties, either promptly upon irradiation or after accumulation of structural damage. Of particular concern are windows, optical fibers, reflectors, and insulators. Many materials currently specified for these components are known to degrade under anticipated operating conditions. However, careful materials selection and modification based on an appropriate irradiation testing program, when combined with optimization of design-sensitive factors such as location, shielding, and ease of replacement, should help to alleviate these materials problems. 30 refs., 2 figs., 1 tab.

  13. Recent advances in Lanczos-based iterative methods for nonsymmetric linear systems

    NASA Technical Reports Server (NTRS)

    Freund, Roland W.; Golub, Gene H.; Nachtigal, Noel M.

    1992-01-01

    In recent years, there has been a true revival of the nonsymmetric Lanczos method. On the one hand, the possible breakdowns in the classical algorithm are now better understood, and so-called look-ahead variants of the Lanczos process have been developed, which remedy this problem. On the other hand, various new Lanczos-based iterative schemes for solving nonsymmetric linear systems have been proposed. This paper gives a survey of some of these recent developments.

  14. ITER's Tokamak Cooling Water System and the the Use of ASME Codes to Comply with French Regulations of Nuclear Pressure Equipment

    SciTech Connect

    Berry, Jan [ORNL] [ORNL; Ferrada, Juan J [ORNL] [ORNL; Curd, Warren [ITER Organization, Saint Paul Lez Durance, France] [ITER Organization, Saint Paul Lez Durance, France; Dell Orco, Dr. Giovanni [ITER Organization, Saint Paul Lez Durance, France] [ITER Organization, Saint Paul Lez Durance, France; Barabash, Vladimir [ITER Organization, Saint Paul Lez Durance, France] [ITER Organization, Saint Paul Lez Durance, France; Kim, Seokho H [ORNL] [ORNL

    2011-01-01

    During inductive plasma operation of ITER, fusion power will reach 500 MW with an energy multiplication factor of 10. The heat will be transferred by the Tokamak Cooling Water System (TCWS) to the environment using the secondary cooling system. Plasma operations are inherently safe even under the most severe postulated accident condition a large, in-vessel break that results in a loss-of-coolant accident. A functioning cooling water system is not required to ensure safe shutdown. Even though ITER is inherently safe, TCWS equipment (e.g., heat exchangers, piping, pressurizers) are classified as safety important components. This is because the water is predicted to contain low-levels of radionuclides (e.g., activated corrosion products, tritium) with activity levels high enough to require the design of components to be in accordance with French regulations for nuclear pressure equipment, i.e., the French Order dated 12 December 2005 (ESPN). ESPN has extended the practical application of the methodology established by the Pressure Equipment Directive (97/23/EC) to nuclear pressure equipment, under French Decree 99-1046 dated 13 December 1999, and Order dated 21 December 1999 (ESP). ASME codes and supplementary analyses (e.g., Failure Modes and Effects Analysis) will be used to demonstrate that the TCWS equipment meets these essential safety requirements. TCWS is being designed to provide not only cooling, with a capacity of approximately 1 GW energy removal, but also elevated temperature baking of first-wall/blanket, vacuum vessel, and divertor. Additional TCWS functions include chemical control of water, draining and drying for maintenance, and facilitation of leak detection/localization. The TCWS interfaces with the majority of ITER systems, including the secondary cooling system. U.S. ITER is responsible for design, engineering, and procurement of the TCWS with industry support from an Engineering Services Organization (ESO) (AREVA Federal Services, with support from Northrop Grumman, and OneCIS). ITER International Organization (ITER-IO) is responsible for design oversight and equipment installation in Cadarache, France. TCWS equipment will be fabricated using ASME design codes with quality assurance and oversight by an Agreed Notified Body (approved by the French regulator) that will ensure regulatory compliance. This paper describes the TCWS design and how U.S. ITER and fabricators will use ASME codes to comply with EU Directives and French Orders and Decrees.

  15. INFORMATION INVASION IN ENTERPRISE SYSTEMS Modelling, simulating and analysing system-level information propagation

    E-print Network

    Henderson, Peter

    INFORMATION INVASION IN ENTERPRISE SYSTEMS Modelling, simulating and analysing system@ecs.soton.ac.uk Keywords: Enterprise information systems, Systems-level modelling, System simulation. A significant problem facing these organisations is how their information systems will cope with inconsistency

  16. Operational Experience with the Scattering Matrix Arc Detection System on the JET ITER-Like Antenna

    SciTech Connect

    Vrancken, M.; Lerche, E.; Dumortier, P.; Durodie, F.; Evrard, M.; Huygen, S.; Ongena, J.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Weynants, R. [LPP/ERM-KMS, Association EURATOM-Belgian State, Brussels (Belgium); Blackman, T.; Graham, M.; Jacquet, P.; Kaye, A.; Mayoral, M.-L.; Nightingale, M. P. S. [EURATOM/UKAEA Fusion Association, Culham Science Center (United Kingdom); Goulding, R. H. [Oak Ridge National Laboratory, Oak Ridge (United States)

    2009-11-26

    The Scattering Matrix Arc Detection System (SMAD) has been fully deployed on all 4 sets of Resonant Double Loop (RDL), Vacuum Transmission Line (VTL) and Antenna Pressurised Transmission Lines (APTL) of the JET ICRF ITER-Like Antenna (ILA) and this has been indispensable for operating at low (real) T-point impedance values to investigate ELM tolerance. This paper describes the necessity of the SMAD vs VSWR (Voltage Standing Wave Ratio) protection system, SMAD commissioning, problems and a number of typical events detected by the SMAD system during operation on plasma.

  17. Characterisation of the Sub-Harmonic Arc Detection System on JET ITER-Like Antenna

    SciTech Connect

    Jacquet, P.; Blackman, T.; Mayoral, M.-L.; Nightingale, M. [EURATOM/UKAEA Fusion Association, Culham Science Center, Abingdon, OX14 3DB (United Kingdom); Berger-By, G. [Association EURATOM/CEA, IRFM, F-13108 Saint-Paul-lez Durances (France); Bobkov, V. [Max Planck IPP/EURATOM Assoziation, D-85748 Garching (Germany); Durodie, F. [Association EURATOM/Belgium State, LPP-ERM/KMS, B-1000 Brussels (Belgium)

    2009-11-26

    A Sub-Harmonic Arc Detection (SHAD) system has been installed on the transmission lines feeding the JET ICRF ITER-like-Antenna (ILA). Along with the commissioning of SHAD, extensive measurements of the RF field in the transmission lines were carried-out using fast sampling (125 Mb/s) oscilloscopes. The system is described, and the SHAD ability to detect arcs during ILA operation (in particular on ELMy H modes) is discussed. Overall, SHAD proved to be efficient, and in some conditions it can offer extra protection in complement to other arc detection systems.

  18. Enhanced iterative learning control for a piezoelectric actuator system using wavelet transform filtering

    NASA Astrophysics Data System (ADS)

    Chien, Chiang-Ju; Lee, Fu-Shin; Wang, Jhen-Cheng

    2007-01-01

    For trajectory tracking of a piezoelectric actuator system, an enhanced iterative learning control (ILC) scheme based on wavelet transform filtering (WTF) is proposed in this research. The enhanced ILC scheme incorporates a state compensation in the ILC formula. Combining state compensation with iterative learning, the scheme enhances tracking accuracies substantially, in comparison to the conventional D-type ILC and a proportional control-aided D-type ILC. The wavelet transform is adopted to filter learnable tracking errors without phase shift. Based on both a time-frequency analysis of tracking errors and a convergence bandwidth analysis of ILC, a two-level WTF is chosen for ILC in this study. The enhanced ILC scheme using WTF was applied to track two desired trajectories, one with a single frequency and the other with multiple frequencies, respectively. Experimental results validate the efficacy of the enhanced ILC in terms of the speed of convergence and the level of long-term tracking errors.

  19. Use of expert systems for naval aviation logistics analyses

    Microsoft Academic Search

    V. K. Wilkinson; R. C. Delozier

    1986-01-01

    This paper addresses the effort to develop a forecasting methodology that will improve the confidence level between predicted and observed values for various logistics elements and translation of that methodology into an expert system to do day-to-day analyses and generate required reports. The paper includes sections on project goals, methodology, and results.

  20. RF Sources for the ITER Ion Cyclotron Heating and Current Drive System

    SciTech Connect

    Hosea, J.; Brunkhorst, C.; Fredd, E.; Goulding, R. H.; Goulding, R. H.; Greenough, N.; Kung, C.; Rasmussen, D. A.; Swain, D. W.; Wilson, J. R.

    2005-10-04

    The RF source requirements for the ITER ion cyclotron (IC) heating and current drive system are very challenging ? 20 MW CW power into an antenna load with a VSWR of up to 2 over the frequency range of 35-65 MHz. For the two present antenna designs under consideration, 8 sources providing 2.5 MW each are to be employed. For these sources, the outputs of two final power amplifiers (FPAs), using the high power CPI 4CM2500KG tube, are combined with a 180? hybrid combiner to easily meet the ITER IC source requirements ? 2.5 MW is supplied at a VSWR of 2 at ? 70% of the maximum tube power available in class B operation. The cylindrical cavity configuration for the FPAs is quite compact so that the 8 combined sources fit into the space allocated at the ITER site with room to spare. The source configuration is described in detail and its projected operating power curves are presented. Although the CPI tube has been shown to be stable under high power operating conditions on many facilities, a test of the combined FPA source arrangement is in preparation using existing high power 30 MHz amplifiers to assure that this configuration can be made robustly stable for all phases at a VSWR up to 2. The possibility of using 12 sources to feed a suitably modified antenna design is also discussed in the context of providing flexibility for specifying the final IC antenna design.

  1. RF Matching Feedback Control Systems on the JET ITER-Like Antenna

    SciTech Connect

    Vrancken, M.; Dumortier, P.; Durodie, F.; Huygen, S.; Lerche, E.; Messiaen, A. M.; Ongena, J.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Weynants, R. [LPP/ERM-KMS, Association EURATOM-Belgian State, Brussels (Belgium); Argouarch, A. [Association EURATOM/CEA, CEA Cadarache (France); Blackman, T.; Graham, M.; Jacquet, P.; Mayoral, M.-L.; Nightingale, M. P. S.; Whitehurst, A. [EURATOM/UKAEA Fusion Association, Culham Science Center (United Kingdom); Goulding, R. H. [Oak Ridge National Laboratory, Oak Ridge (United States)

    2009-11-26

    Ion Cyclotron Resonance Frequency (ICRF) antennas achieve maximum power transfer from RF generator to plasma load by establishing an impedance match. The JET ITER-Like Antenna (ILA) consists of 4 mutually coupled resonators that need to be matched simultaneously and whose resonant states need to be accurately controlled by several available actuators to couple maximum power and to achieve optimal ELM resilience. The operation of the matching system is described. Experimental operation revealed some phenomena and sensitivities that did not surface from simulation alone and that should be taken into account for the design of future ICRF antennae systems.

  2. _______________________________________2001 Conference on Information Sciences and Systems, The Johns Hopkins University, March 2123, 2001 Iterative Multiuser Detection and Decoding for DMT VDSL Systems

    E-print Network

    Dai, Huaiyu

    , The Johns Hopkins University, March 21­23, 2001 Iterative Multiuser Detection and Decoding for DMT VDSL (DMT) very-high-rate digital subscriber line (VDSL) system to combat crosstalk signals and to ob- tain substantial coding gain. The proposed iterative DMT receiver is shown to achieve an overall 7.0 dB gain over

  3. On the Convergence of Iterative Methods for Linear Systems arising from Singularly Perturbed Equations

    E-print Network

    Farrell, Paul A.

    considerable Appeared in Proceedings of the Copper Mountain Conference on Iterative Methods 1998 The work for the error for each iteration as a function of the perturbation parameter and the number of mesh intervals n

  4. A protection system for the JET ITER-like wall based on imaging diagnostics

    SciTech Connect

    Arnoux, G.; Balboa, I.; Balshaw, N.; Beldishevski, M.; Cramp, S.; Felton, R.; Goodyear, A.; Horton, A.; Kinna, D.; McCullen, P.; Obrejan, K.; Patel, K.; Lomas, P. J.; Rimini, F.; Stamp, M.; Stephen, A.; Thomas, P. D.; Williams, J.; Wilson, J.; Zastrow, K.-D. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); and others

    2012-10-15

    The new JET ITER-like wall (made of beryllium and tungsten) is more fragile than the former carbon fiber composite wall and requires active protection to prevent excessive heat loads on the plasma facing components (PFC). Analog CCD cameras operating in the near infrared wavelength are used to measure surface temperature of the PFCs. Region of interest (ROI) analysis is performed in real time and the maximum temperature measured in each ROI is sent to the vessel thermal map. The protection of the ITER-like wall system started in October 2011 and has already successfully led to a safe landing of the plasma when hot spots were observed on the Be main chamber PFCs. Divertor protection is more of a challenge due to dust deposits that often generate false hot spots. In this contribution we describe the camera, data capture and real time processing systems. We discuss the calibration strategy for the temperature measurements with cross validation with thermal IR cameras and bi-color pyrometers. Most importantly, we demonstrate that a protection system based on CCD cameras can work and show examples of hot spot detections that stop the plasma pulse. The limits of such a design and the associated constraints on the operations are also presented.

  5. Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems

    SciTech Connect

    Fricke, Brian A [ORNL] [ORNL; Bansal, Pradeep [ORNL] [ORNL; Zha, Shitong [Hillphoenix] [Hillphoenix

    2013-01-01

    This paper presents energy and life cycle climate performance (LCCP) analyses of a variety of supermarket refrigeration systems to identify designs that exhibit low environmental impact and high energy efficiency. EnergyPlus was used to model refrigeration systems in a variety of climate zones across the United States. The refrigeration systems that were modeled include the traditional multiplex DX system, cascade systems with secondary loops and the transcritical CO2 system. Furthermore, a variety of refrigerants were investigated, including R-32, R-134a, R-404A, R-1234yf, R-717, and R-744. LCCP analysis was used to determine the direct and indirect carbon dioxide emissions resulting from the operation of the various refrigeration systems over their lifetimes. Our analysis revealed that high-efficiency supermarket refrigeration systems may result in up to 44% less energy consumption and 78% reduced carbon dioxide emissions compared to the baseline multiplex DX system. This is an encouraging result for legislators, policy makers and supermarket owners to select low emission, high-efficiency commercial refrigeration system designs for future retrofit and new projects.

  6. Modeling and Simulation of the ITER First Wall/Blanket Primary Heat Transfer System

    SciTech Connect

    Ying, Alice [University of California, Los Angeles] [University of California, Los Angeles; Popov, Emilian L [ORNL] [ORNL

    2011-01-01

    ITER inductive power operation is modeled and simulated using a thermal-hydraulics system code (RELAP5) integrated with a 3-D CFD (SC-Tetra) code. The Primary Heat Transfer System (PHTS) functions are predicted together with the main parameters operational ranges. The control algorithm strategy and derivation are summarized as well. The First Wall and Blanket modules are the primary components of PHTS, used to remove the major part of the thermal heat from the plasma. The modules represent a set of flow channels in solid metal structure that serve to absorb the radiation heat and nuclear heating from the fusion reactions and to provide shield for the vacuum vessel. The blanket modules are water cooled. The cooling is forced convective with constant blanket inlet temperature and mass flow rate. Three independent water loops supply coolant to the three blanket sectors. The main equipment of each loop consists of a pump, a steam pressurizer and a heat exchanger. A major feature of ITER is the pulsed operation. The plasma does not burn continuously, but on intervals with large periods of no power between them. This specific feature causes design challenges to accommodate the thermal expansion of the coolant during the pulse period and requires active temperature control to maintain a constant blanket inlet temperature.

  7. Preliminary system design and analysis of an optimized infrastructure for ITER prototype cryoline test

    NASA Astrophysics Data System (ADS)

    Shah, Nitin Dineshkumar; Bhattacharya, Ritendra Nath; Sarkar, Biswanath; Badgujar, Satish; Vaghela, Hitensinh; Patel, Pratik

    2012-06-01

    The prototype cryoline (PTCL) for ITER is a representative cryoline from the complicated network of all cryolines for the project. The PTCL is being designed with four process pipes at temperature level 4.5 K, two process pipes at 80 K and will be manufactured in a 1:1 scale with a configuration of main line and branch line including vacuum barriers. The test objectives are focused to demonstrate best possible risk free engineering and reliable manufacturing of the cryolines as per the ITER functional requirements. The measured physical parameters will assess the confirmation for acceptable heat loads, stresses and mechanical integrity in normal, off-normal and accident scenarios such as a break of insulation vacuum (BIV). The PTCL will be tested to measure heat load at 4.5 K with scaled mass flow rate having the thermal shield at 80 K. Necessary infrastructure along with the control system have been designed, analyzed and optimized within the imposed constraints to fulfill the test objectives. The system approach along with instrumentations and controls, results of the optimization study, and its usefulness in the present context within the constraints of economics and schedule have been described.

  8. Low-Bit Rate Feedback Strategies for Iterative IA-Precoded MIMO-OFDM-Based Systems

    PubMed Central

    Teodoro, Sara; Silva, Adăo; Dinis, Rui; Gameiro, Atílio

    2014-01-01

    Interference alignment (IA) is a promising technique that allows high-capacity gains in interference channels, but which requires the knowledge of the channel state information (CSI) for all the system links. We design low-complexity and low-bit rate feedback strategies where a quantized version of some CSI parameters is fed back from the user terminal (UT) to the base station (BS), which shares it with the other BSs through a limited-capacity backhaul network. This information is then used by BSs to perform the overall IA design. With the proposed strategies, we only need to send part of the CSI information, and this can even be sent only once for a set of data blocks transmitted over time-varying channels. These strategies are applied to iterative MMSE-based IA techniques for the downlink of broadband wireless OFDM systems with limited feedback. A new robust iterative IA technique, where channel quantization errors are taken into account in IA design, is also proposed and evaluated. With our proposed strategies, we need a small number of quantization bits to transmit and share the CSI, when comparing with the techniques used in previous works, while allowing performance close to the one obtained with perfect channel knowledge. PMID:24678274

  9. RAMI Analysis for Designing and Optimizing Tokamak Cooling Water System (TCWS) for the ITER's Fusion Reactor

    SciTech Connect

    Ferrada, Juan J [ORNL] [ORNL; Reiersen, Wayne T [ORNL] [ORNL

    2011-01-01

    U.S.-ITER is responsible for the design, engineering, and procurement of the Tokamak Cooling Water System (TCWS). TCWS is designed to provide cooling and baking for client systems that include the first wall/blanket, vacuum vessel, divertor, and neutral beam injector. Additional operations that support these primary functions include chemical control of water provided to client systems, draining and drying for maintenance, and leak detection/localization. TCWS interfaces with 27 systems including the secondary cooling system, which rejects this heat to the environment. TCWS transfers heat generated in the Tokamak during nominal pulsed operation - 850 MW at up to 150 C and 4.2 MPa water pressure. Impurities are diffused from in-vessel components and the vacuum vessel by water baking at 200-240 C at up to 4.4 MPa. TCWS is complex because it serves vital functions for four primary clients whose performance is critical to ITER's success and interfaces with more than 20 additional ITER systems. Conceptual design of this one-of-a-kind cooling system has been completed; however, several issues remain that must be resolved before moving to the next stage of the design process. The 2004 baseline design indicated cooling loops that have no fault tolerance for component failures. During plasma operation, each cooling loop relies on a single pump, a single pressurizer, and one heat exchanger. Consequently, failure of any of these would render TCWS inoperable, resulting in plasma shutdown. The application of reliability, availability, maintainability, and inspectability (RAMI) tools during the different stages of TCWS design is crucial for optimization purposes and for maintaining compliance with project requirements. RAMI analysis will indicate appropriate equipment redundancy that provides graceful degradation in the event of an equipment failure. This analysis helps demonstrate that using proven, commercially available equipment is better than using custom-designed equipment with no field experience and lowers specific costs while providing higher reliability. This paper presents a brief description of the TCWS conceptual design and the application of RAMI tools to optimize the design at different stages during the project.

  10. Iterative solutions to the steady-state density matrix for optomechanical systems.

    PubMed

    Nation, P D; Johansson, J R; Blencowe, M P; Rimberg, A J

    2015-01-01

    We present a sparse matrix permutation from graph theory that gives stable incomplete lower-upper preconditioners necessary for iterative solutions to the steady-state density matrix for quantum optomechanical systems. This reordering is efficient, adding little overhead to the computation, and results in a marked reduction in both memory and runtime requirements compared to other solution methods, with performance gains increasing with system size. Either of these benchmarks can be tuned via the preconditioner accuracy and solution tolerance. This reordering optimizes the condition number of the approximate inverse and is the only method found to be stable at large Hilbert space dimensions. This allows for steady-state solutions to otherwise intractable quantum optomechanical systems. PMID:25679739

  11. Mechanical strength of an ITER coil insulation system under static and dynamic load after reactor irradiation

    NASA Astrophysics Data System (ADS)

    Bittner-Rohrhofer, K.; Humer, K.; Weber, H. W.; Hamada, K.; Sugimoto, M.; Okuno, K.

    2002-12-01

    The insulation system proposed by the Japanese Home Team for the ITER Toroidal Field coil (TF coil) is a T-glass-fiber/Kapton reinforced epoxy prepreg system. In order to assess the material performance under the actual operating conditions of the coils, the insulation system was irradiated in the TRIGA reactor (Vienna) to a fast neutron fluence of 2×10 22 m -2 ( E>0.1 MeV). After measurements of swelling, all mechanical tests were carried out at 77 K. Tensile and short-beam-shear (SBS) tests were performed under static loading conditions. In addition, tension-tension fatigue experiments up to about 10 6 cycles were made. The laminate swells in the through-thickness direction by 0.86% at the highest dose level. The fatigue tests as well as the static tests do not show significant influences of the irradiation on the mechanical behavior of this composite.

  12. YALINA analytical benchmark analyses using the deterministic ERANOS code system.

    SciTech Connect

    Gohar, Y.; Aliberti, G.; Nuclear Engineering Division

    2009-08-31

    The growing stockpile of nuclear waste constitutes a severe challenge for the mankind for more than hundred thousand years. To reduce the radiotoxicity of the nuclear waste, the Accelerator Driven System (ADS) has been proposed. One of the most important issues of ADSs technology is the choice of the appropriate neutron spectrum for the transmutation of Minor Actinides (MA) and Long Lived Fission Products (LLFP). This report presents the analytical analyses obtained with the deterministic ERANOS code system for the YALINA facility within: (a) the collaboration between Argonne National Laboratory (ANL) of USA and the Joint Institute for Power and Nuclear Research (JIPNR) Sosny of Belarus; and (b) the IAEA coordinated research projects for accelerator driven systems (ADS). This activity is conducted as a part of the Russian Research Reactor Fuel Return (RRRFR) Program and the Global Threat Reduction Initiative (GTRI) of DOE/NNSA.

  13. The distributed system for collecting and analysing selected medical data

    NASA Astrophysics Data System (ADS)

    Makal, Jaros?aw; Id?kowski, Adam; Walendziuk, Wojciech; Miro?czuk, Marcin

    2006-10-01

    In this paper the structure of a three-tiered distributed system for collecting and analysing medical examination data is presented. The idea of this work is to make an assistant tool for urologists to diagnose the lower urinary track diseases and their symptoms easier. The data (which are processed from the files made in the uroflowmeters - devices for measuring urine flow rate) are presented in web browser. It has been done with the use of PHP scripts which are accessed through Apache web server.

  14. Information security system by iterative multiple-phase retrieval and pixel random permutation

    NASA Astrophysics Data System (ADS)

    Meng, Xiang-Feng; Cai, Lu-Zhong; Yang, Xiu-Lun; Shen, Xiao-Xia; Dong, Guo-Yan

    2006-05-01

    A novel information security system based on multiple-phase retrieval by an iterative Fresnel-transform algorithm and pixel random permutation (PRP) technique is proposed. In this method a series of phase masks cascaded in free space are employed and the phase distributions of all the masks are adjusted simultaneously in each iteration. It can achieve faster convergence and better quality of the recovered image compared with double-phase encoding and a similar approach in the spatial-frequency domain with the same number of phase masks and can provide a higher degree of freedom in key space with more geometric parameters as supplementary keys. Furthermore, the security level of this method is greatly improved by the introduction of the PRP technique. The feasibility of this method and its robustness against occlusion and additional noise attacks are verified by computer simulations. The performance of this technique for different numbers of phase masks and quantized phase levels is investigated systematically with the correlation coefficient and mean square error as convergence criterions.

  15. Fast secant methods for the iterative solution of large nonsymmetric linear systems

    NASA Technical Reports Server (NTRS)

    Deuflhard, Peter; Freund, Roland; Walter, Artur

    1990-01-01

    A family of secant methods based on general rank-1 updates was revisited in view of the construction of iterative solvers for large non-Hermitian linear systems. As it turns out, both Broyden's good and bad update techniques play a special role, but should be associated with two different line search principles. For Broyden's bad update technique, a minimum residual principle is natural, thus making it theoretically comparable with a series of well known algorithms like GMRES. Broyden's good update technique, however, is shown to be naturally linked with a minimum next correction principle, which asymptotically mimics a minimum error principle. The two minimization principles differ significantly for sufficiently large system dimension. Numerical experiments on discretized partial differential equations of convection diffusion type in 2-D with integral layers give a first impression of the possible power of the derived good Broyden variant.

  16. Iterative reconstruction using a Monte Carlo based system transfer matrix for dedicated breast positron emission tomography

    SciTech Connect

    Saha, Krishnendu [Ohio Medical Physics Consulting, Dublin, Ohio 43017 (United States); Straus, Kenneth J.; Glick, Stephen J. [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States); Chen, Yu. [Department of Radiation Oncology, Columbia University, New York, New York 10032 (United States)

    2014-08-28

    To maximize sensitivity, it is desirable that ring Positron Emission Tomography (PET) systems dedicated for imaging the breast have a small bore. Unfortunately, due to parallax error this causes substantial degradation in spatial resolution for objects near the periphery of the breast. In this work, a framework for computing and incorporating an accurate system matrix into iterative reconstruction is presented in an effort to reduce spatial resolution degradation towards the periphery of the breast. The GATE Monte Carlo Simulation software was utilized to accurately model the system matrix for a breast PET system. A strategy for increasing the count statistics in the system matrix computation and for reducing the system element storage space was used by calculating only a subset of matrix elements and then estimating the rest of the elements by using the geometric symmetry of the cylindrical scanner. To implement this strategy, polar voxel basis functions were used to represent the object, resulting in a block-circulant system matrix. Simulation studies using a breast PET scanner model with ring geometry demonstrated improved contrast at 45% reduced noise level and 1.5 to 3 times resolution performance improvement when compared to MLEM reconstruction using a simple line-integral model. The GATE based system matrix reconstruction technique promises to improve resolution and noise performance and reduce image distortion at FOV periphery compared to line-integral based system matrix reconstruction.

  17. An alpha particle measurement system using an energetic neutral helium beam in ITER (invited)

    SciTech Connect

    Sasao, M.; Tanaka, N.; Terai, K.; Kaneko, O. [Graduate school of Engineering, Tohoku University, Sendai 980-8579 (Japan); Kisaki, M.; Kobuchi, T.; Tsumori, K.; Okamoto, A.; Kitajima, S. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Shinto, K. [IFMIF R and D Center, Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Wada, M. [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2012-02-15

    An energetic helium neutral beam is involved in the beam neutralization measurement system of alpha particles confined in a DT fusion plasma. A full size strong-focusing He{sup +} ion source (2 A, the beam radius of 11.3 mm, the beam energy less than 20 keV). Present strong-focusing He{sup +} ion source shows an emittance diagram separated for each beamlet of multiple apertures without phase space mixing, despite the space charge of a beamlet is asymmetric and the beam flow is non-laminar. The emittance of beamlets in the peripheral region was larger than that of center. The heat load to the plasma electrode was studied to estimate the duty factor for the ITER application.

  18. Synthesis of Trigeneration Systems: Sensitivity Analyses and Resilience

    PubMed Central

    Carvalho, Monica; Lozano, Miguel A.; Ramos, José; Serra, Luis M.

    2013-01-01

    This paper presents sensitivity and resilience analyses for a trigeneration system designed for a hospital. The following information is utilized to formulate an integer linear programming model: (1) energy service demands of the hospital, (2) technical and economical characteristics of the potential technologies for installation, (3) prices of the available utilities interchanged, and (4) financial parameters of the project. The solution of the model, minimizing the annual total cost, provides the optimal configuration of the system (technologies installed and number of pieces of equipment) and the optimal operation mode (operational load of equipment, interchange of utilities with the environment, convenience of wasting cogenerated heat, etc.) at each temporal interval defining the demand. The broad range of technical, economic, and institutional uncertainties throughout the life cycle of energy supply systems for buildings makes it necessary to delve more deeply into the fundamental properties of resilient systems: feasibility, flexibility and robustness. The resilience of the obtained solution is tested by varying, within reasonable limits, selected parameters: energy demand, amortization and maintenance factor, natural gas price, self-consumption of electricity, and time-of-delivery feed-in tariffs. PMID:24453881

  19. Synthesis of trigeneration systems: sensitivity analyses and resilience.

    PubMed

    Carvalho, Monica; Lozano, Miguel A; Ramos, José; Serra, Luis M

    2013-01-01

    This paper presents sensitivity and resilience analyses for a trigeneration system designed for a hospital. The following information is utilized to formulate an integer linear programming model: (1) energy service demands of the hospital, (2) technical and economical characteristics of the potential technologies for installation, (3) prices of the available utilities interchanged, and (4) financial parameters of the project. The solution of the model, minimizing the annual total cost, provides the optimal configuration of the system (technologies installed and number of pieces of equipment) and the optimal operation mode (operational load of equipment, interchange of utilities with the environment, convenience of wasting cogenerated heat, etc.) at each temporal interval defining the demand. The broad range of technical, economic, and institutional uncertainties throughout the life cycle of energy supply systems for buildings makes it necessary to delve more deeply into the fundamental properties of resilient systems: feasibility, flexibility and robustness. The resilience of the obtained solution is tested by varying, within reasonable limits, selected parameters: energy demand, amortization and maintenance factor, natural gas price, self-consumption of electricity, and time-of-delivery feed-in tariffs. PMID:24453881

  20. INVESTIGATION OF A TEST LOOP FOR THE COOLING SYSTEM OF THE ITER TF COIL UNDER PULSED HEAT LOAD

    SciTech Connect

    Rousset, B.; Girard, A.; Maze, S.; Poncet, J. M.; Roussel, P. [DRFMC/SBT/Commissariat a l'Energie Atomique (CEA), Grenoble, 38054 (France); Kalinin, V. [ITER, Cadarache (France); Murdoch, D.; Sanmarti, M. [European Fusion Development Agreement (EFDA), Garching, Germany/Barcelona (Spain)

    2008-03-16

    CEA is involved in the design of the cooling scheme of the future ITER tokamak. Pulsed operation of ITER will result in heat load variations (which refrigerators have difficulties to cope with). A load smoothing device has been proposed by the ITER team which needs to be validated. To do this, a scaled-down experiment (hereafter also called model) has been proposed and studied in the framework of an EFDA sub-task. This paper presents the test loop dimensioning and the preliminary design for constructing the model. The choice of the relevant design criteria had to be defined so as to obtain in fine a geometric ratio between the ITER system and the model. It is shown that this ratio is then applicable for the mass flow rates as well as the different volumes (heat exchanger, pipes,...) existing on ITER and on the proposed experimental model. Details of the scaling, model design and 3D views corresponding to this preliminary study are presented in this paper.

  1. Reproducible analyses of microbial food for advanced life support systems

    NASA Technical Reports Server (NTRS)

    Petersen, Gene R.

    1988-01-01

    The use of yeasts in controlled ecological life support systems (CELSS) for microbial food regeneration in space required the accurate and reproducible analysis of intracellular carbohydrate and protein levels. The reproducible analysis of glycogen was a key element in estimating overall content of edibles in candidate yeast strains. Typical analytical methods for estimating glycogen in Saccharomyces were not found to be entirely aplicable to other candidate strains. Rigorous cell lysis coupled with acid/base fractionation followed by specific enzymatic glycogen analyses were required to obtain accurate results in two strains of Candida. A profile of edible fractions of these strains was then determined. The suitability of yeasts as food sources in CELSS food production processes is discussed.

  2. A computationally efficient decorrelator for multibeam antennas using an iterative method with fast correlation in DS-CDMA systems

    Microsoft Academic Search

    Sungbin Imt; Eunsung Kim; Yoan Shin

    1999-01-01

    We present a fast method of reducing the computational complexity of a decorrelator, which is one of the suboptimal methods for eliminating multiple access interference (MAI) in direct sequence-code division multiple access (DS-CDMA) systems. The proposed approach rests upon the following: (1) incorporating a multibeam antenna to partially suppress the MAI, (2) an iterative method to obtain decorrelated signals rather

  3. Initial results of systems analysis of the ETR\\/ITER (Engineering Test Reactor\\/International Thermonuclear Experimental Reactor) design space

    Microsoft Academic Search

    Y. K. M. Peng; J. D. Galambos; R. L. Reid; D. J. Strickler; S. Kalsi; L. Deleanu

    1987-01-01

    Preliminary versions of the Engineering Test Reactor (ETR) systems code TETRA (Tokamak Engineering Test Reactor Analysis), which determines design solutions by the method of constrained optimization, are used to characterize the International Thermonuclear Experimental Reactor (ITER) and its design parameter space. We find that the physics objectives of high ignition margin and high plasma current lead to minimum size at

  4. Iterative Solution of Linear Systems in the 20th Century Yousef Saad \\Lambda Henk A. van der Vorst y

    E-print Network

    Vorst, Henk A.

    Iterative Solution of Linear Systems in the 20­th Century Yousef Saad \\Lambda Henk A. van der Vorst has been triggered by a problem that can be posed simply as: Given A 2 C m\\Thetan , b 2 C m , find solution vector (s) x 2 C n such that Ax = b. Many scientific problems lead to the requirement to solve

  5. Two Systems Safety Analyses Useful in Examining the Vulnerabilities of Security Systems

    Microsoft Academic Search

    Norman E. Groner

    2008-01-01

    Systems safety methods can be used to better understand the threats and vulnerabilities in complex technological systems. They provide comprehensive, well-reasoned, and easily communicated analyses of the vulnerabilities of security systems. This article provides a primer on the use of the two most adaptable and useful among the many systems safety methods: Failure Modes and Effects Analysis and Fault Tree

  6. Evaluation of static mixer flow enhancements for cryogenic viscous compressor prototype for ITER vacuum system

    NASA Astrophysics Data System (ADS)

    Duckworth, Robert C.; Baylor, Larry R.; Meitner, Steven J.; Combs, Stephen K.; Ha, Tam; Morrow, Michael; Biewer, T.; Rasmussen, David A.; Hechler, Michael P.; Pearce, Robert J. H.; Dremel, Mattias; Boissin, J.-C.

    2014-01-01

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (up to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype.

  7. Evaluation of Static Mixer Flow Enhancements for Cryogenic Viscous Compressor Prototype for ITER Vacuum System

    SciTech Connect

    Duckworth, Robert C [ORNL] [ORNL; Baylor, Larry R [ORNL] [ORNL; Meitner, Steven J [ORNL] [ORNL; Combs, Stephen Kirk [ORNL] [ORNL; Ha, Tam T [ORNL] [ORNL; Morrow, Michael [ORNL] [ORNL; Biewer, Theodore M [ORNL] [ORNL; Rasmussen, David A [ORNL] [ORNL; Hechler, Michael P [ORNL] [ORNL; Pearce, R.J.H. [ITER Organization, Cadarache, France] [ITER Organization, Cadarache, France; Dremel, M. [ITER Organization, Cadarache, France] [ITER Organization, Cadarache, France; Boissin, Jean Claude [Consultant] [Consultant

    2014-01-01

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (50 to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype

  8. Evaluation of static mixer flow enhancements for cryogenic viscous compressor prototype for ITER vacuum system

    SciTech Connect

    Duckworth, Robert C.; Baylor, Larry R.; Meitner, Steven J.; Combs, Stephen K.; Ha, Tam; Morrow, Michael; Biewer, T. [Fusion and Materials for Nuclear System Division, Oak Ridge National Laboratory, Oak Ridge (United States); Rasmussen, David A.; Hechler, Michael P. [U.S. ITER Project Office, Oak Ridge National Laboratory, Oak Ridge (United States); Pearce, Robert J. H.; Dremel, Mattias [ITER Organization, 13115 St. Paul-lez-Durance (France); Boissin, J.-C. [Consultant, Grenoble (France)

    2014-01-29

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (up to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype.

  9. GoldenBraid: An Iterative Cloning System for Standardized Assembly of Reusable Genetic Modules

    PubMed Central

    Sarrion-Perdigones, Alejandro; Falconi, Erica Elvira; Zandalinas, Sara I.; Juárez, Paloma; Fernández-del-Carmen, Asun; Granell, Antonio; Orzaez, Diego

    2011-01-01

    Synthetic Biology requires efficient and versatile DNA assembly systems to facilitate the building of new genetic modules/pathways from basic DNA parts in a standardized way. Here we present GoldenBraid (GB), a standardized assembly system based on type IIS restriction enzymes that allows the indefinite growth of reusable gene modules made of standardized DNA pieces. The GB system consists of a set of four destination plasmids (pDGBs) designed to incorporate multipartite assemblies made of standard DNA parts and to combine them binarily to build increasingly complex multigene constructs. The relative position of type IIS restriction sites inside pDGB vectors introduces a double loop (“braid”) topology in the cloning strategy that allows the indefinite growth of composite parts through the succession of iterative assembling steps, while the overall simplicity of the system is maintained. We propose the use of GoldenBraid as an assembly standard for Plant Synthetic Biology. For this purpose we have GB-adapted a set of binary plasmids for A. tumefaciens-mediated plant transformation. Fast GB-engineering of several multigene T-DNAs, including two alternative modules made of five reusable devices each, and comprising a total of 19 basic parts are also described. PMID:21750718

  10. Requirements and interfaces to cryogenic and power supply plants for the ITER magnet system

    SciTech Connect

    Yoshida, K.; Kalinin, V.; Stoner, S. [ITER Joint Central Team, Naka-machi, Naka-gun, Ibaraki-ken (Japan)] [and others

    1996-12-31

    This paper describes the requirements and interfaces of cryogenic and power supply plants for the ITER magnet system. The heat loads and mass flow rates of the magnet system is evaluated to keep coil temperature within 6.5 K during the plasma operation of 2200 s. The helium consumption in the current leads is estimated for a current feed of 4.5 MA from 4 K to 300 K. The location of the electrical insulation breaks is compared near winding and outside of cryostat. The terminal box is designed for interfacing the cryogenic and power supply systems. Separate vacuums for the cryostat and the cryolines facilitate maintenance of all cryogenic components without warm-up of the whole system. A superconducting busbar is used to supply current from a current connector at the coil to the vapor-cooled lead in the coil terminal box. The layout of cryogenic lines and equipment is designed to consider space limitations and routing restrictions in the tokamak hall and the electrical termination building. The main parameters of the cryogenic plant (cryoplant) are discussed.

  11. GoldenBraid: an iterative cloning system for standardized assembly of reusable genetic modules.

    PubMed

    Sarrion-Perdigones, Alejandro; Falconi, Erica Elvira; Zandalinas, Sara I; Juárez, Paloma; Fernández-del-Carmen, Asun; Granell, Antonio; Orzaez, Diego

    2011-01-01

    Synthetic Biology requires efficient and versatile DNA assembly systems to facilitate the building of new genetic modules/pathways from basic DNA parts in a standardized way. Here we present GoldenBraid (GB), a standardized assembly system based on type IIS restriction enzymes that allows the indefinite growth of reusable gene modules made of standardized DNA pieces. The GB system consists of a set of four destination plasmids (pDGBs) designed to incorporate multipartite assemblies made of standard DNA parts and to combine them binarily to build increasingly complex multigene constructs. The relative position of type IIS restriction sites inside pDGB vectors introduces a double loop ("braid") topology in the cloning strategy that allows the indefinite growth of composite parts through the succession of iterative assembling steps, while the overall simplicity of the system is maintained. We propose the use of GoldenBraid as an assembly standard for Plant Synthetic Biology. For this purpose we have GB-adapted a set of binary plasmids for A. tumefaciens-mediated plant transformation. Fast GB-engineering of several multigene T-DNAs, including two alternative modules made of five reusable devices each, and comprising a total of 19 basic parts are also described. PMID:21750718

  12. Fusion Power Measurement Using a Combined Neutron Spectrometer-Camera System at ITER

    SciTech Connect

    Sjoestrand, Henrik; Sunden, E. Andersson; Conroy, S.; Ericsson, G.; Johnson, M. Gatu; Giacomelli, L.; Hellesen, C.; Hjalmarsson, A.; Ronchi, E.; Weiszflog, M. [INF, Uppsala University, EURATOM-VR Association, Uppsala (Sweden); Kaellne, J. [Engineering Sciences, Uppsala University, Uppsala (Sweden)

    2008-03-12

    A central task for fusion plasma diagnostics is to measure the 2.5 and 14 MeV neutron emission rate in order to determine the fusion power. A new method for determining the neutron yield has been developed at JET. It makes use of the magnetic proton recoil neutron spectrometer and a neutron camera and provides the neutron yield with small systematic errors. At ITER a similar system could operate if a high-resolution, high-performance neutron spectrometer similar to the MPR was installed. In this paper, we present how such system could be implemented and how well it would perform under different assumption of plasma scenarios and diagnostic capabilities. It is found that the systematic uncertainty for using such a system as an absolute calibration reference is as low as 3% and hence it would be an excellent candidate for the calibration of neutron monitors such as fission chambers. It is also shown that the system could provide a 1 ms time resolved estimation of the neutron rate with a total uncertainty of 5%.

  13. An Illumination Modeling System for Human Factors Analyses

    NASA Technical Reports Server (NTRS)

    Huynh, Thong; Maida, James C.; Bond, Robert L. (Technical Monitor)

    2002-01-01

    Seeing is critical to human performance. Lighting is critical for seeing. Therefore, lighting is critical to human performance. This is common sense, and here on earth, it is easily taken for granted. However, on orbit, because the sun will rise or set every 45 minutes on average, humans working in space must cope with extremely dynamic lighting conditions. Contrast conditions of harsh shadowing and glare is also severe. The prediction of lighting conditions for critical operations is essential. Crew training can factor lighting into the lesson plans when necessary. Mission planners can determine whether low-light video cameras are required or whether additional luminaires need to be flown. The optimization of the quantity and quality of light is needed because of the effects on crew safety, on electrical power and on equipment maintainability. To address all of these issues, an illumination modeling system has been developed by the Graphics Research and Analyses Facility (GRAF) and Lighting Environment Test Facility (LETF) in the Space Human Factors Laboratory at NASA Johnson Space Center. The system uses physically based ray tracing software (Radiance) developed at Lawrence Berkeley Laboratories, a human factors oriented geometric modeling system (PLAID) and an extensive database of humans and environments. Material reflectivity properties of major surfaces and critical surfaces are measured using a gonio-reflectometer. Luminaires (lights) are measured for beam spread distribution, color and intensity. Video camera performances are measured for color and light sensitivity. 3D geometric models of humans and the environment are combined with the material and light models to form a system capable of predicting lighting conditions and visibility conditions in space.

  14. Shear/compressive properties of candidate ITER insulation systems at low temperatures

    NASA Astrophysics Data System (ADS)

    Fabian, P. E.; Reed, R. P.; Schutz, J. B.; Bauer-McDaniel, T. S.

    Shear/compression tests were performed at 76 and 4 K on candidate composite insulation systems for the International Thermonuclear Experimental Reactor (ITER) toroidal field coils. The insulation systems tested consisted of vacuum-pressure impregnated, pre-impregnated, and high-pressure laminate systems that included electrical barriers such as polyimide film or mica/glass. Sandwich-style specimens, in which the composite insulation is bonded to two AISI 316 stainless steel chips, were used. Two specimens were loaded at an angle, which resulted in combined shear and compressive stresses, and tested simultaneously. Various shear/compression ratios were achieved by using different test fixtures, each at a different angle (15 °, 45 °, 75 ° and 84 °) from the vertical direction. The shear strengths of specimens loaded at 15 ° to 75 ° increased with increasing compressive stress; these specimens experienced shear failures. For specimens loaded at 84 °, the compressive stress increased and the shear strength decreased; the failure modes of these specimens were more compressive than shear. The effects of electrical barriers on shear/compressive properties are also reported.

  15. Modifying the Medical Research Council grading system through Rasch analyses.

    PubMed

    Vanhoutte, Els Karla; Faber, Catharina Gerritdina; van Nes, Sonja Ingrid; Jacobs, Bart Casper; van Doorn, Pieter Antoon; van Koningsveld, Rinske; Cornblath, David Reid; van der Kooi, Anneke Jelly; Cats, Elisabeth Aviva; van den Berg, Leonard Hendrik; Notermans, Nicolette Claudia; van der Pol, Willem Lodewijk; Hermans, Mieke Catharina Elisabeth; van der Beek, Nadine Anna Maria Elisabeth; Gorson, Kenneth Craig; Eurelings, Marijke; Engelsman, Jeroen; Boot, Hendrik; Meijer, Ronaldus Jacobus; Lauria, Giuseppe; Tennant, Alan; Merkies, Ingemar Sergio José

    2012-05-01

    The Medical Research Council grading system has served through decades for the evaluation of muscle strength and has been recognized as a cardinal feature of daily neurological, rehabilitation and general medicine examination of patients, despite being respectfully criticized due to the unequal width of its response options. No study has systematically examined, through modern psychometric approach, whether physicians are able to properly use the Medical Research Council grades. The objectives of this study were: (i) to investigate physicians' ability to discriminate among the Medical Research Council categories in patients with different neuromuscular disorders and with various degrees of weakness through thresholds examination using Rasch analysis as a modern psychometric method; (ii) to examine possible factors influencing physicians' ability to apply the Medical Research Council categories through differential item function analyses; and (iii) to examine whether the widely used Medical Research Council 12 muscles sum score in patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy would meet Rasch model's expectations. A total of 1065 patients were included from nine cohorts with the following diseases: Guillain-Barré syndrome (n?=?480); myotonic dystrophy type-1 (n?=?169); chronic inflammatory demyelinating polyradiculoneuropathy (n?=?139); limb-girdle muscular dystrophy (n?=?105); multifocal motor neuropathy (n?=?102); Pompe's disease (n?=?62) and monoclonal gammopathy of undetermined related polyneuropathy (n?=?8). Medical Research Council data of 72 muscles were collected. Rasch analyses were performed on Medical Research Council data for each cohort separately and after pooling data at the muscle level to increase category frequencies, and on the Medical Research Council sum score in patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy. Disordered thresholds were demonstrated in 74-79% of the muscles examined, indicating physicians' inability to discriminate between most Medical Research Council categories. Factors such as physicians' experience or illness type did not influence these findings. Thresholds were restored after rescoring the Medical Research Council grades from six to four options (0, paralysis; 1, severe weakness; 2, slight weakness; 3, normal strength). The Medical Research Council sum score acceptably fulfilled Rasch model expectations after rescoring the response options and creating subsets to resolve local dependency and item bias on diagnosis. In conclusion, a modified, Rasch-built four response category Medical Research Council grading system is proposed, resolving clinicians' inability to differentiate among its original response categories and improving clinical applicability. A modified Medical Research Council sum score at the interval level is presented and is recommended for future studies in Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy. PMID:22189568

  16. Subspace Iteration Method for Complex Eigenvalue Problems with Nonsymmetric Matrices in Aeroelastic System

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Lung, Shu

    2009-01-01

    Modern airplane design is a multidisciplinary task which combines several disciplines such as structures, aerodynamics, flight controls, and sometimes heat transfer. Historically, analytical and experimental investigations concerning the interaction of the elastic airframe with aerodynamic and in retia loads have been conducted during the design phase to determine the existence of aeroelastic instabilities, so called flutter .With the advent and increased usage of flight control systems, there is also a likelihood of instabilities caused by the interaction of the flight control system and the aeroelastic response of the airplane, known as aeroservoelastic instabilities. An in -house code MPASES (Ref. 1), modified from PASES (Ref. 2), is a general purpose digital computer program for the analysis of the closed-loop stability problem. This program used subroutines given in the International Mathematical and Statistical Library (IMSL) (Ref. 3) to compute all of the real and/or complex conjugate pairs of eigenvalues of the Hessenberg matrix. For high fidelity configuration, these aeroelastic system matrices are large and compute all eigenvalues will be time consuming. A subspace iteration method (Ref. 4) for complex eigenvalues problems with nonsymmetric matrices has been formulated and incorporated into the modified program for aeroservoelastic stability (MPASES code). Subspace iteration method only solve for the lowest p eigenvalues and corresponding eigenvectors for aeroelastic and aeroservoelastic analysis. In general, the selection of p is ranging from 10 for wing flutter analysis to 50 for an entire aircraft flutter analysis. The application of this newly incorporated code is an experiment known as the Aerostructures Test Wing (ATW) which was designed by the National Aeronautic and Space Administration (NASA) Dryden Flight Research Center, Edwards, California to research aeroelastic instabilities. Specifically, this experiment was used to study an instability known as flutter. ATW was a small-scale airplane wing comprised of an airfoil and wing tip boom. This wing was formulated based on a NACA-65A004 airfoil shape with a 3.28 aspect ratio. The wing had a span of 18 inch with root chord length of 13.2 inch and tip chord length of 8.7 inch. The total area of this wing was 197 square inch. The wing tip boom was a 1 inch diameter hollow tube of length 21.5 inch. The total weight of the wing was 2.66 lbs.

  17. Study on mitigation of pulsed heat load for ITER cryogenic system

    NASA Astrophysics Data System (ADS)

    Peng, N.; Xiong, L. Y.; Jiang, Y. C.; Tang, J. C.; Liu, L. Q.

    2015-03-01

    One of the key requirements for ITER cryogenic system is the mitigation of the pulsed heat load deposited in the magnet system due to magnetic field variation and pulsed DT neutron production. As one of the control strategies, bypass valves of Toroidal Field (TF) case helium loop would be adjusted to mitigate the pulsed heat load to the LHe plant. A quasi-3D time-dependent thermal-hydraulic analysis of the TF winding packs and TF case has been performed to study the behaviors of TF magnets during the reference plasma scenario with the pulses of 400 s burn and repetition time of 1800 s. The model is based on a 1D helium flow and quasi-3D solid heat conduction model. The whole TF magnet is simulated taking into account thermal conduction between winding pack and case which are cooled separately. The heat loads are given as input information, which include AC losses in the conductor, eddy current losses in the structure, thermal radiation, thermal conduction and nuclear heating. The simulation results indicate that the temperature variation of TF magnet stays within the allowable range when the smooth control strategy is active.

  18. Experimental proof of a load resilient external matching solution for the ITER ICRH system

    NASA Astrophysics Data System (ADS)

    Vervier, M.; Messiaen, A.; Dumortier, P.; Lamalle, P.

    2005-09-01

    A reliable load resilient external matching scheme for the ITER ICRH system has been successfully tested on the mock-up of the external matching system with variable plasma load simulation. To avoid the deleterious mutual coupling effects the power has been passively distributed among the upper half and the bottom half of the 24 radiating straps of the antenna plug. In this plug the straps are grouped in 8 triplets by 4-ports junctions. The 4 top and 4 bottom triplets are respectively put in parallel outside the antenna plug near a voltage anti-node by means of T junctions. The load resilient matching is then obtained by a 4 parameters single "conjugate T" (CT) configuration. For an antenna loading variation of about 1 to 8 ?/m the VSWR at the power source remains below 1.3. The maximum voltage along the line remains equal to the one in the antenna plug and there is a fair power share between the straps. A ?0?0 toroidal phasing is easily obtained. The poloidal phasing between the top and bottom triplets is determined by the loading. A straightforward matching procedure is described. Good load resilience is also obtained by replacing the CT by one hybrid.

  19. Improvements in Hanford TRU Program Utilizing Systems Modeling and Analyses

    SciTech Connect

    Baynes, P.A.; Bailey, K.B.; McKenney, D.E. [Fluor Hanford, Inc., Richland, WA (United States); Uytioco, E. [Fluor Government Group, Richland, WA (United States)

    2008-07-01

    Hanford's Transuranic (TRU) Program is responsible for certifying contact-handled (CH) TRU waste and shipping the certified waste to the Waste Isolation Pilot Plant (WIPP). Hanford's CH TRU waste includes material that is in retrievable storage as well as above ground storage, and newly generated waste. Certifying a typical container entails retrieving and then characterizing it (Non-Destructive Examination [NDE], Non-Destructive Assay [NDA], and Head Space Gas Sampling [HSG]), validating records (data review and reconciliation), and designating the container for a payload. The certified payload is then shipped to WIPP. Systems modeling and analysis techniques were applied to Hanford's TRU Program to help streamline the certification process and increase shipping rates. The modeling and analysis yields several benefits: - Maintains visibility on system performance and predicts downstream consequences of production issues. - Predicts future system performance with higher confidence, based on tracking past performance. - Applies speculation analyses to determine the impact of proposed changes (e.g., apparent shortage of feed should not be used as basis to reassign personnel if more feed is coming in the queue). - Positively identifies the appropriate queue for all containers (e.g., discovered several containers that were not actively being worked because they were in the wrong 'physical' location - method used previously for queuing up containers). - Identifies anomalies with the various data systems used to track inventory (e.g., dimensional differences for Standard Waste Boxes). A model of the TRU Program certification process was created using custom queries of the multiple databases for managing waste containers. The model was developed using a simplified process chart based on the expected path for a typical container. The process chart was augmented with the remediation path for containers that do not meet acceptance criteria for WIPP. Containers are sorted into queues based on their current status in the process. A container can be in only one queue at any given time. Existing data systems are queried to establish the quantity of containers in each queue on any given day. This sets the amount of feed available that is then modeled to be processed according to the daily production plans. The daily production plans were created by identifying the equipment necessary and the staff that performs each process step, and determining the expected production rate for each step. Production performance is monitored on a weekly basis with Project senior staff to establish a total operating efficiency (TOE) for each step (comparing actual performance to production capacity). The unit operations were modeled to be constrained by each day's feed queue plus the performance of the preceding step. The TOE for each unit operation was applied to an integrated model to determine bottlenecks and identify areas for improvement. All of the steps were linked to predict future system performance based on available feed and integrated system-level TOE. It has been determined that at times sub-optimization of a particular unit operation is necessary to ensure the system remains balanced (e.g., having excess capacity in assay does no good if there is no feed available because the real-time radiography [RTR] is working at half capacity). Several recommendations have been provided to the Project management team resulting in improvements in the performance of TRU certification activities by Hanford's TRU Program. (authors)

  20. Enhanced Iterative Learning Control with Applications to A Wafer Scanner System

    E-print Network

    Yu, Shu-Wen

    2011-01-01

    Lee, and W. Kim. Model-based iterative learning control withlearning control based on an inverse process model. Journalmodel uncertainty. Optimization-based ILC uses a quadratic performance criterion to obtain an op- timal learning

  1. A Comparison of Modifications to MELCOR versions 1.8.2 and 1.8.6 for ITER Safety Analysis

    Microsoft Academic Search

    B. J. Merrill; P. W. Humrickhouse

    2010-01-01

    During the Engineering Design Activity of the International Thermonuclear Experimental Reactor (ITER), the MELCOR 1.8.2 code was selected as one of several codes to be used to perform ITER safety analyses [1]. MELCOR was chosen because it has the capability of predicting coolant pressure, temperature, mass flow rate, and radionuclide and aerosol transport in nuclear facilities and reactor cooling systems.

  2. Design and Tests of 500kW RF Windows for the ITER LHCD System

    E-print Network

    Hillairet, Julien; Faure, N; Achard, J; Delpech, L; Goniche, M; Larroque, S; Magne, R; Marfisi, L; Park, S; Poli, S; Dechambre, N; Vulliez, K

    2015-01-01

    In the frame of a R\\&D effort conducted by CEA toward the design and the qualification of a 5 GHz LHCD system for the ITER tokamak, two 5 GHz 500 kW/5 s windows have been designed, manufactured and tested at high power in collaboration with the National Fusion Research Institute (NFRI). The window design rely on a symmetrical pill-box concept with a cylindrical beryllium oxide ceramic brazed on an actively water cooled copper skirt. The ceramic RF properties have been measured on a test sample to get realistic values for guiding the design. Low power measurements of the manufactured windows show return losses below-32 dB and insertion losses between-0.01 dB and-0.05 dB, with an optimum frequency shifted toward lower frequencies. High power tests conducted at NFRI show unexpected total power loss for both windows. The ceramic temperature during RF pulses has been found to reach unexpected high temperature, preventing these windows to be used under CW conditions. A post-mortem RF analysis of samples taken f...

  3. Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

    NASA Astrophysics Data System (ADS)

    Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

    2014-10-01

    High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 ? and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  4. Performance of the ITER ICRH system as expected from TOPICA and ANTITER II modelling

    NASA Astrophysics Data System (ADS)

    Messiaen, A.; Koch, R.; Weynants, R. R.; Dumortier, P.; Louche, F.; Maggiora, R.; Milanesio, D.

    2010-02-01

    The performance on plasma of the antennas of the proposed ITER ICRF system is evaluated by means of the antenna 24 × 24 impedance matrix provided by the TOPICA code and confirmed and interpreted by the semi-analytical code ANTITER II (summarized in an appendix). From this analysis the following system characteristics can be derived: (1) a roughly constant power capability in the entire 40-55 MHz frequency band with the same maximum voltage in the eight feeding lines is obtained for all the considered heating and current drive phasings on account of the broadbanding effect of service stubs. (2) The power capability of the array significantly depends on the distance of the antenna to the separatrix, the density profile in the scrape-off layer (SOL) and on the strap current toroidal and poloidal phasings. The dependence on phasing is stronger for wider SOL. (3) To exceed a radiated power capability of 20 MW per antenna array in the upper part of the frequency band, with a separatrix-wall distance of 17 cm and a conservative short decay plasma edge density profile, the system voltage stand-off must be 45 kV and well chosen combinations of toroidal and poloidal phasing are needed. (4) On account of the plasma gyrotropy and of poloidal magnetic field, special care must be taken in choosing the optimal toroidal current drive and poloidal phasings. The ANTITER II analysis shows furthermore that important coaxial and surface mode excitation can only be expected in the monopole toroidal phasing, that strong wave reflection from a steep density profile significantly reduces the coupling even if the separatrix is closer to the antenna and that the part of the edge density profile having a density lower than the cut-off density pertaining to the considered phasing does not significantly contribute to the coupling.

  5. Critical Design Issues of Tokamak Cooling Water System of ITER's Fusion Reactor

    SciTech Connect

    Kim, Seokho H [ORNL] [ORNL; Berry, Jan [ORNL] [ORNL

    2011-01-01

    U.S. ITER is responsible for the design, engineering, and procurement of the Tokamak Cooling Water System (TCWS). The TCWS transfers heat generated in the Tokamak to cooling water during nominal pulsed operation 850 MW at up to 150 C and 4.2 MPa water pressure. This water contains radionuclides because impurities (e.g., tritium) diffuse from in-vessel components and the vacuum vessel by water baking at 200 240 C at up to 4.4MPa, and corrosion products become activated by neutron bombardment. The system is designated as safety important class (SIC) and will be fabricated to comply with the French Order concerning nuclear pressure equipment (December 2005) and the EU Pressure Equipment Directive using ASME Section VIII, Div 2 design codes. The complexity of the TCWS design and fabrication presents unique challenges. Conceptual design of this one-of-a-kind cooling system has been completed with several issues that need to be resolved to move to next stage of the design. Those issues include flow balancing between over hundreds of branch pipelines in parallel to supply cooling water to blankets, determination of optimum flow velocity while minimizing the potential for cavitation damage, design for freezing protection for cooling water flowing through cryostat (freezing) environment, requirements for high-energy piping design, and electromagnetic impact to piping and components. Although the TCWS consists of standard commercial components such as piping with valves and fittings, heat exchangers, and pumps, complex requirements present interesting design challenges. This paper presents a brief description of TCWS conceptual design and critical design issues that need to be resolved.

  6. A PIV\\/PTV system for analysing turbulent bubbly flows

    Microsoft Academic Search

    D. Bröder; M. Sommerfeld

    Bubble columns are widely used in chemical industry and biotechnology. Flow and turbulence in such an apparatus are induced by the bubble rise, and the bubble behaviour is strongly affected by swarm effects (i.e. the interaction between bubbles). For analysing the bubble swarm behaviour and simultaneously evaluating the flow structure and bubble-induced turbulence in a bubble column of 140 mm

  7. Bounds on the map threshold of iterative decoding systems with erasure noise 

    E-print Network

    Wang, Chia-Wen

    2008-10-10

    . : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 8 3 Message-passing decoding of the the simple irregular LDPC code with the received word (0, ?, 1, ?, 1). The three rows correspond to iterations 0 to 2. After the rst iteration we recover x2 = 1, after the second we know that x4 = 1. This means... that for this case the recovered codeword is (0, 1, 1, 1, 1). : : : : : : : : : : : : : 10 4 The evolution of the decoding process for the dd pair ( (x); (x)) = (x2; x3), and = 0:6. The initial fraction of erasure messages emitted by the bit nodes is xl = 1. After...

  8. Rescheduling with iterative repair

    NASA Technical Reports Server (NTRS)

    Zweben, Monte; Davis, Eugene; Daun, Brian; Deale, Michael

    1992-01-01

    This paper presents a new approach to rescheduling called constraint-based iterative repair. This approach gives our system the ability to satisfy domain constraints, address optimization concerns, minimize perturbation to the original schedule, produce modified schedules, quickly, and exhibits 'anytime' behavior. The system begins with an initial, flawed schedule and then iteratively repairs constraint violations until a conflict-free schedule is produced. In an empirical demonstration, we vary the importance of minimizing perturbation and report how fast the system is able to resolve conflicts in a given time bound. We also show the anytime characteristics of the system. These experiments were performed within the domain of Space Shuttle ground processing.

  9. An iterative possibilistic image segmentation system: Application to breast cancer detection

    Microsoft Academic Search

    Waël Eziddin; J. Montagner; B. Solaiman

    2010-01-01

    A novel approach for digital mammograms segmentation is proposed. This approach aims to segment the mammograms using an iterative fusion process of information obtained from multiple sources of knowledge (contextual, image processing algorithm, a priori knowledge, etc). Initial Fuzzy Membership Maps (IFMMs) of different thematic classes are first estimated using available information. These IFMM's are then interpreted as Possibility Distribution

  10. A design study of water detritation and hydrogen isotope separation systems for ITER

    Microsoft Academic Search

    Y. Iwai; H. Yoshida; T. Yamanishi; S. Senrui; M. Nishi

    2000-01-01

    A preliminary design study of the combined electrolysis catalytic exchange (CECE) process by using existing plant technology at the Japanese heavy water reactor (Fugen) was carried out for International Thermonuclear Experimental Reactor (ITER). Because of the large separation factor, the required column height is substantially reduced compared with a vacuum water distillation (WD) column. A preliminary design study of the

  11. Design status of the ITER ECRH upper launcher mm-wave system

    Microsoft Academic Search

    J.-D. Landis; R. Chavan; R. Bertizzolo; A. Collazos; F. Dolizy; F. Felici; F. Sanchez; M. Henderson

    2009-01-01

    The purpose of the ITER electron cyclotron resonance heating (ECRH) upper launcher (UL), or antennae will be to provide localised current drive by accurately directing mm-wave beams up to 2MW, out of the four allocated upper port plugs, at chosen rational magnetic flux surfaces in order to stabilise neoclassical tearing modes (NTMs). This paper will present an overview of the

  12. New Techniques for Analysing Axisymmetric Gravitational Systems. 1. Vacuum Fields

    E-print Network

    Chris Doran; Anthony Lasenby

    2002-11-21

    A new framework for analysing the gravitational fields in a stationary, axisymmetric configuration is introduced. The method is used to construct a complete set of field equations for the vacuum region outside a rotating source. These equations are under-determined. Restricting the Weyl tensor to type D produces a set of equations which can be solved, and a range of new techniques are introduced to simplify the problem. Imposing the further condition that the solution is asymptotically flat yields the Kerr solution uniquely. The implications of this result for the no-hair theorem are discussed. The techniques developed here have many other applications, which are described in the conclusions.

  13. Analyses of power system vulnerability and total transfer capability 

    E-print Network

    Yu, Xingbin

    2006-04-12

    Modern power systems are now stepping into the post-restructuring era, in which utility industries as well as ISOs (Independent System Operators) are involved. Attention needs to be paid to the reliability study of power ...

  14. Spaceborne power systems preference analyses. Volume 2: Decision analysis

    NASA Technical Reports Server (NTRS)

    Smith, J. H.; Feinberg, A.; Miles, R. F., Jr.

    1985-01-01

    Sixteen alternative spaceborne nuclear power system concepts were ranked using multiattribute decision analysis. The purpose of the ranking was to identify promising concepts for further technology development and the issues associated with such development. Four groups were interviewed to obtain preference. The four groups were: safety, systems definition and design, technology assessment, and mission analysis. The highest ranked systems were the heat-pipe thermoelectric systems, heat-pipe Stirling, in-core thermionic, and liquid-metal thermoelectric systems. The next group contained the liquid-metal Stirling, heat-pipe Alkali Metal Thermoelectric Converter (AMTEC), heat-pipe Brayton, liquid-metal out-of-core thermionic, and heat-pipe Rankine systems. The least preferred systems were the liquid-metal AMTEC, heat-pipe thermophotovoltaic, liquid-metal Brayton and Rankine, and gas-cooled Brayton. The three nonheat-pipe technologies selected matched the top three nonheat-pipe systems ranked by this study.

  15. Parallel iterative solution of large-scale acoustic scattering problems using exact non reflecting conditions on distributed memory computer systems

    NASA Astrophysics Data System (ADS)

    Ianculescu, Cristian; Thompson, Lonny L.

    2003-04-01

    Parallel iterative methods for fast solution of large-scale acoustic radiation and scattering problems are developed using exact Dirichlet-to-Neumann (DtN) nonreflecting boundaries. For elongated scatterers such as submarines, it is shown that the generalization of the DtN to elliptical/spheroidal artificial boundaries improves significantly the computational efficiency of accurate finite element methods for the solution of acoustic scattering problems. The outer-product structure of the DtN map is exploited as a low-rank update of the system matrix to efficiently compute the matrix-by-vector products found in Krylov subspace based iterative methods. For the complex non-Hermitian matrices resulting from the Helmholtz equation, a distributed-memory parallel BICG-STAB iterative method is used in conjunction with a hybrid parallel SSOR/Jacobi preconditioner. The domain decomposition with interface minimization was performed to ensure optimal inter-processor communication. For the distributed memory architectures tested, including Linux/Intel Beowulf clusters, when implemented as a low-rank update, the nonlocal character of the DtN map shows little impact on the scale up or parallel efficiency compared to approximate local boundary conditions. [Work supported by NSF.

  16. Air pollution control system research: An iterative approach to developing affordable systems

    SciTech Connect

    Watt, L.C.; Cannon, F.S.; Heinsohn, R.J.; Spaeder, T.A.; Darvin, C.H.

    1993-12-31

    The research will be accomplished on lab scale, pilot scale, and production air pollution control systems (APCS). The production system, to be installed at Marine Corps Logistics Base (MCLB) Barstow, CA, will treat the exhaust from three paint booths which will be modified to recirculate a large percentage of their exhaust. These recirculation systems are, themselves, a critical element in the overall R and D effort. The goal of the program is to conduct an R and D effort which will improve and demonstrate a combination of technologies intended to make VOC treatment both effective and affordable. The US Marine Corps, the other services and industry will each benefit.

  17. Harmonic and transient overvoltage analyses in arc furnace power systems

    Microsoft Academic Search

    S. R. Mendis; D. A. Gonzalez

    1992-01-01

    The authors present guidelines for analyzing harmonics and transient overvoltages generated by arc furnaces. Computer simulation techniques for creating accurate models for the analysis of arc furnace power systems are also discussed. Simulation guidelines are outlined in detail to assist the power systems engineer in performing a complete and accurate study of arc furnace power systems. These guidelines can be

  18. Analysing fundamental properties of marker-based vision system designs

    E-print Network

    Cambridge, University of

    -based Vision (MBV) systems. We present a theoretical analysis of the performance of basic tag designs which software toolkit for building Marker-based Vision (MBV) systems that can identify and accurately locate been the traditional development do- main for such Marker-Based Vision (MBV) systems (Billinghurst

  19. Decision Support System for Cephalometric Analyses of Orthodontics

    Microsoft Academic Search

    Shu-Li Wang; Shin-Lian Wang; Fan Wu

    2009-01-01

    The paper develops a decision support system for orthodontics, which is evidence-based and can reduce the bias of subjective judgments of orthodontists, meet the expectation of the patients, and increase the cost performance and effectiveness. The steps of constructing the system can be divided into eight steps, selecting influencing factors, adjust images, measurement of image, collecting related data, validation rules,

  20. Understanding ERP system implementation in a hospital by analysing stakeholders

    Microsoft Academic Search

    Albert Boonstra; Mark J. G. Govers

    2009-01-01

    Implementing enterprise resource planning (ERP) systems requires significant organisational, as well as technical, changes. These will affect stakeholders with varying perspectives and interests in the system. This is particularly the case in health care, as a feature of this sector is that responsibility of services is shared between many autonomous units. In these and similar settings, it is essential to

  1. Analyses of grounded and ungrounded photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Bower, Ward; Wiles, John

    Photovoltaic (PV) modules and photovoltaic balance of systems equipment are designed, manufactured, and marketed internationally. Each country or group of countries has a set of electrical safety codes, either in place or evolving, that guide and regulate the design and installation of PV power systems. A basic difference in these codes is that some require hard (low-resistance) grounding (the United States and Canada) and others opt for an essentially ungrounded system (Europe and Japan). The significant design and safety issues that exist between the two grounding concepts affect the international PV industry's ability to economically and effectively design and market safe, reliable, and durable PV systems in the global market place. This paper will analyze the technical and safety benefits, penalties, and costs of both grounded arid ungrounded PV systems. The existing grounding practice in several typical countries will be addressed.

  2. Moral Sentiments in the Iterated Prisoner's Dilemma and in Multi-Agent Systems

    Microsoft Academic Search

    Rafael H. Bordini; Ana L. C. Bazzan; Rosa M. Vicari; John A. Campbell

    2000-01-01

    We present a simulation of a society of agents where some of them have moral sentiments towards the agents that belong to the same social group, using the Iterated Prisoner's Dilemma as a metaphor for the social interactions. Besides the well-understood phenomenon of short-sighted, self-interested agents performing well in the short-term but ruining their chances of such performance in the

  3. Democratizing systems immunology with modular transcriptional repertoire analyses.

    PubMed

    Chaussabel, Damien; Baldwin, Nicole

    2014-04-01

    Individual elements that constitute the immune system have been characterized over the few past decades, mostly through reductionist approaches. The introduction of large-scale profiling platforms has more recently facilitated the assessment of these elements on a global scale. However, the analysis and the interpretation of such large-scale datasets remains a challenge and a barrier for the wider adoption of systems approaches in immunological and clinical studies. In this Innovation article, we describe an analytical strategy that relies on the a priori determination of co-dependent gene sets for a given biological system. Such modular transcriptional repertoires can in turn be used to simplify the analysis and the interpretation of large-scale datasets, and to design targeted immune fingerprinting assays and web applications that will further facilitate the dissemination of systems approaches in immunology. PMID:24662387

  4. Analyses Of Transient Events In Complex Valve and Feed Systems

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Hosangadi, Ashvin; Cavallo, Peter; Daines, Russell

    2005-01-01

    Valve systems in rocket propulsion systems and testing facilities are constantly subject to dynamic events resulting from the timing of valve motion leading to unsteady fluctuations in pressure and mass flow. Such events can also be accompanied by cavitation, resonance, system vibration leading to catastrophic failure. High-fidelity dynamic computational simulations of valve operation can yield important information of valve response to varying flow conditions. Prediction of transient behavior related to valve motion can serve as guidelines for valve scheduling, which is of crucial importance in engine operation and testing. In this paper, we present simulations of the diverse unsteady phenomena related to valve and feed systems that include valve stall, valve timing studies as well as cavitation instabilities in components utilized in the test loop.

  5. A Framework for Integrated Component and System Analyses of Instabilities

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Erwin, James; Arunajatesan, Srinivasan; Cattafesta, Lou; Liu, Fei

    2010-01-01

    Instabilities associated with fluid handling and operation in liquid rocket propulsion systems and test facilities usually manifest themselves as structural vibrations or some form of structural damage. While the source of the instability is directly related to the performance of a component such as a turbopump, valve or a flow control element, the associated pressure fluctuations as they propagate through the system have the potential to amplify and resonate with natural modes of the structural elements and components of the system. In this paper, the authors have developed an innovative multi-level approach that involves analysis at the component and systems level. The primary source of the unsteadiness is modeled with a high-fidelity hybrid RANS/LES based CFD methodology that has been previously used to study instabilities in feed systems. This high fidelity approach is used to quantify the instability and understand the physics associated with the instability. System response to the driving instability is determined through a transfer matrix approach wherein the incoming and outgoing pressure and velocity fluctuations are related through a transfer (or transmission) matrix. The coefficients of the transfer matrix for each component (i.e. valve, pipe, orifice etc.) are individually derived from the flow physics associated with the component. A demonstration case representing a test loop/test facility comprised of a network of elements is constructed with the transfer matrix approach and the amplification of modes analyzed as the instability propagates through the test loop.

  6. Various Analyses of Structures and Systems Pertaining to Optical Communications

    NASA Technical Reports Server (NTRS)

    Petersen, Collin W.

    2005-01-01

    The Optical Communications Group intends to experiment with a 2 by 2 meter Fresnel lens to determine its likelihood as an alternative to focusing mirrors for optical communications. The lens was delivered in four sections. A support structure was required for the lens in order to hold the four sections in a single flat plane with an adjustable degree angle. In order to use the 200-in. Hale telescope for optical communications purposes, an optical filter membrane must used to pass the communications wavelength while blocking sunlight wavelengths. This filter must withstand wind gusts of up to 50 miles per hour. Stress analysis predicts that the membrane will survive with a safety factor greater than two. The methods used were verified by pressure testing the material. Mechanical and thermodynamic analyses were performed on a simple Golay cell in order to optimize its dimensions for best performance. Flexures are examined as an inexpensive alternative to traditional methods for kinematically constraining a 1.5-meter spherical mirror.

  7. Statistical model based iterative reconstruction (MBIR) in clinical CT systems: Experimental assessment of noise performance

    SciTech Connect

    Li, Ke; Tang, Jie [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Chen, Guang-Hong, E-mail: gchen7@wisc.edu [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 and Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 and Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)

    2014-04-15

    Purpose: To reduce radiation dose in CT imaging, the statistical model based iterative reconstruction (MBIR) method has been introduced for clinical use. Based on the principle of MBIR and its nonlinear nature, the noise performance of MBIR is expected to be different from that of the well-understood filtered backprojection (FBP) reconstruction method. The purpose of this work is to experimentally assess the unique noise characteristics of MBIR using a state-of-the-art clinical CT system. Methods: Three physical phantoms, including a water cylinder and two pediatric head phantoms, were scanned in axial scanning mode using a 64-slice CT scanner (Discovery CT750 HD, GE Healthcare, Waukesha, WI) at seven different mAs levels (5, 12.5, 25, 50, 100, 200, 300). At each mAs level, each phantom was repeatedly scanned 50 times to generate an image ensemble for noise analysis. Both the FBP method with a standard kernel and the MBIR method (Veo{sup ®}, GE Healthcare, Waukesha, WI) were used for CT image reconstruction. Three-dimensional (3D) noise power spectrum (NPS), two-dimensional (2D) NPS, and zero-dimensional NPS (noise variance) were assessed both globally and locally. Noise magnitude, noise spatial correlation, noise spatial uniformity and their dose dependence were examined for the two reconstruction methods. Results: (1) At each dose level and at each frequency, the magnitude of the NPS of MBIR was smaller than that of FBP. (2) While the shape of the NPS of FBP was dose-independent, the shape of the NPS of MBIR was strongly dose-dependent; lower dose lead to a “redder” NPS with a lower mean frequency value. (3) The noise standard deviation (?) of MBIR and dose were found to be related through a power law of ????(dose){sup ??} with the component ? ? 0.25, which violated the classical ????(dose){sup ?0.5} power law in FBP. (4) With MBIR, noise reduction was most prominent for thin image slices. (5) MBIR lead to better noise spatial uniformity when compared with FBP. (6) A composite image generated from two MBIR images acquired at two different dose levels (D1 and D2) demonstrated lower noise than that of an image acquired at a dose level of D1+D2. Conclusions: The noise characteristics of the MBIR method are significantly different from those of the FBP method. The well known tradeoff relationship between CT image noise and radiation dose has been modified by MBIR to establish a more gradual dependence of noise on dose. Additionally, some other CT noise properties that had been well understood based on the linear system theory have also been altered by MBIR. Clinical CT scan protocols that had been optimized based on the classical CT noise properties need to be carefully re-evaluated for systems equipped with MBIR in order to maximize the method's potential clinical benefits in dose reduction and/or in CT image quality improvement.

  8. Experimental benchmark for piping system dynamic-response analyses

    SciTech Connect

    Not Available

    1981-01-01

    This paper describes the scope and status of a piping system dynamics test program. A 0.20 m(8 in.) nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Particular attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed.

  9. Analysing In nite-State Systems by Combining Equivalence Reduction

    E-print Network

    Mailund, Thomas

    Aarhus N, DENMARK, mailund@daimi.au.dk Abstract. The sweep-line method is a state space exploration performance in state space exploration often leads to an in#12;nite state space: The progress in the system to delete certain states during state space exploration and to reclaim memory. When calculating the state

  10. Analysing In nite-State Systems by Combining

    E-print Network

    Mailund, Thomas

    is a state space exploration method for on-the- y veri#12;cation aimed at systems exhibiting progress to improve memory performance in state space exploration often leads to an in#12;nite state space approximation of the reachablitity relation that makes it possible to delete certain states during state space

  11. BNL Pulsed Magnet Magnet System Cooldown and Structural Analyses

    E-print Network

    McDonald, Kirk

    Cooling Between Shots, with a Helium Purge to Limit Activation BNL Pulsed Magnet ­Inertially Cooled , 30K-10 Dist Category UC20 c,dated October 1986 Channel Edge Thermal Model #12;Pulse Magnet Cooldown 66K He 85K - Choose Insulation Systems. Determine where Kapton is used. · Stress Analysis, Assess Radial load

  12. Conceptual design analyses for Hanford Site deployable remote spectroscopy systems

    SciTech Connect

    Philipp, B.L.; Reich, F.R.

    1994-09-01

    This document identifies potential remote, NIR spectroscopic waste surface moisture monitoring system design alternatives to be operated inside one of the Hanford Site, high level, nuclear waste storage tanks. Potential tank waste moisture data impacts from the remote NIR signal transfer through high humidity vapor space is evaluated.

  13. Mining and analysing security goal models in health information systems

    Microsoft Academic Search

    Jens H. Weber-Jahnke; Adeniyi Onabajo

    2009-01-01

    Large-scale health information software systems have to adhere to complex, multi-lateral security and privacy regulations. Such regulations are typically defined in form of natural language (NL) documents. There is little methodological support for bridging the gap between NL regulations and the requirements engineering methods that have been developed by the software engineering community. This paper presents a method and tool

  14. Analysing emerging innovation systems: a functions approach to foresight

    Microsoft Academic Search

    Floortje Alkemade; Chris Kleinschmidt; Marko Hekkert

    2007-01-01

    The success of sustainable innovations depends in a large part on their environment, the Innovation System (IS). Insight into the structure and dynamics of the IS is thus of crucial importance in foresight studies and policy analysis. The analytical framework outlined in this paper allows us to study relations between the components, the structure and the functionality of the IS

  15. New progress of ITER-PF strand production in WST

    NASA Astrophysics Data System (ADS)

    Li, J. F.; Liu, W. T.; Yan, L. X.; H, J.; Gao, H. X.; Liu, J. W.; Du, S. J.; Liu, X. H.; Feng, Y.; Zhang, P. X.; Liu, S.; Li, H. W.; Niu, E. W.

    2014-05-01

    ITER Poloidal Field (PF) systems consist of 6 independent coils with different dimensions and require NbTi superconductor and copper strands. Western Superconducting Technologies Co.,Ltd.(WST) will supply PF2-5 NbTi strand for ITER, and over 14,000 km of NbTi strands have been produced in the past two years. Main performance of NbTi strands, including critical current, n value, wire diameter, Cu/non-Cu ratio, hysteresis loss and RRR are reported and analysed in this paper.

  16. Active control of repetitive impulsive noise in a non-minimum phase system using an optimal iterative learning control algorithm

    NASA Astrophysics Data System (ADS)

    Zhou, Y. L.; Yin, Y. X.; Zhang, Q. Z.

    2013-09-01

    In this paper, active control of repetitive impulsive noise is studied. An optimal iterative learning control (ILC) algorithm is developed for an active noise control (ANC) system with a non-minimum phase secondary path. A non-causal transversal finite impulse response (FIR) filter is used as the ILC learning filter, and the impulse response coefficients of the FIR filter are designed according to the asymptotically stable and monotonically convergent criterion in time domain. Computer simulations have been carried out to suggest that the proposed algorithm is effective for attenuating repetitive impulsive noise, and then the proposed algorithm has been implemented in an experimental ANC system. Experimental results show that the proposed scheme has good performance for repetitive impulsive noise attenuation in a non-minimum phase ANC system.

  17. Web-Based Assessment and Test Analyses (WATA) System: Development and Evaluation

    ERIC Educational Resources Information Center

    Wang, T. H.; Wang, K. H.; Wang, W. L.; Huang, S. C.; Chen, S. Y.

    2004-01-01

    This study introduces the development of a Web-based assessment system, the Web-based Assessment and Test Analyses (WATA) system, and examines its impacts on teacher education. The WATA system is a follow-on system, which applies the Triple-A Model (assembling, administering, and appraising). Its functions include (1) an engine for teachers to…

  18. Overview of ITER ProjectOverview of ITER Project --organizational structure,organizational structure,

    E-print Network

    System, Diagnostic Systems at university and research institutions · Development of ITER Plasma Control of Plasma Simulator 2. Development of advanced diagnostics and heating systems 3. Development of Operation #12;General Principles of ITER Operation -common understanding- · ITER s objective will be pursued

  19. Iterative image reconstruction in helical cone-beam x-ray CT using a stored system matrix approach.

    PubMed

    Xu, Jingyan; Tsui, Benjamin M W

    2012-06-01

    We present a stored system matrix (SM) approach for iterative x-ray CT image reconstruction with helical cone-beam geometry. Because of the symmetry of a helical source trajectory, it is sufficient to calculate and store the SM entries for one transaxial slice only and for all source positions illuminating the slice. This is made possible by (1) selecting the reconstruction slice thickness to be an integer multiple of the source translation per projection view, and (2) discretizing the 3D reconstruction volume on a rotated stack of slices. Using the proposed method, the memory requirement for reconstructing a full field-of-view of clinical scanners is manageable on current computing platforms. The same storage principle can be generalized and applied to volume-of-interest (VOI) image reconstruction for helical cone-beam CT. In this case, the stored SM entries correspond to a partial- or full-ring region on one transaxial slice, and for all source positions illuminating the ring. The size and location of the ring depend on the size and the location of the VOI and the scan geometry. We demonstrate by both computer simulations and clinical patient data the speed and efficacy of iterative image reconstruction using the stored SM approach. PMID:22581218

  20. ITER's Tokamak Cooling Water System and the the Use of ASME Codes to Comply with French Regulations of Nuclear Pressure Equipment

    Microsoft Academic Search

    Jan Berry; Juan J Ferrada; Warren Curd; Giovanni Dell Orco; Vladimir Barabash; Seokho H Kim

    2011-01-01

    During inductive plasma operation of ITER, fusion power will reach 500 MW with an energy multiplication factor of 10. The heat will be transferred by the Tokamak Cooling Water System (TCWS) to the environment using the secondary cooling system. Plasma operations are inherently safe even under the most severe postulated accident condition a large, in-vessel break that results in a

  1. An iterative model-based cogging compensator for the Green Bank Telescope servo system

    NASA Astrophysics Data System (ADS)

    Franke, Timothy; Weadon, Timothy; Ford, John; Garcia-Sanz, Mario

    2014-07-01

    This paper outlines an anti-cogging methodology and summarizes the current state of motor cogging cancellation on the Green Bank Telescope (GBT). An iterative, model-based algorithm is developed for finding the anticogging signal which yields rapid convergence. This method fills a gap in present methodologies in that it can serve as a drop-in cogging solution which operates in the presence of unknown structural dynamics as well as with an existing feedback controller. The algorithm is described and demonstrated on a 40 HP DC brushed motor test bed and also on the GBT's elevation axis motors. Results and implementation experience from deploying the algorithm on a motor test bed and on the GBT are discussed.

  2. USING SECURITY ATTACK SCENARIOS TO ANALYSE SECURITY DURING INFORMATION SYSTEMS DESIGN

    E-print Network

    the development lifecycles and not how the security of an information system can be tested during the analysis on the use of scenarios, to test the reaction of an information system against potential security attacks. 1USING SECURITY ATTACK SCENARIOS TO ANALYSE SECURITY DURING INFORMATION SYSTEMS DESIGN Haralambos

  3. Fatigue behavior of an insulation system for the ITER magnets in the load and strain controlled mode

    Microsoft Academic Search

    R. Prokopec; K. Humer; H. W. Weber

    2007-01-01

    The application of glass-fiber reinforced plastics as insulation materials for fusion magnet coils (e.g. of ITER) requires a full mechanical material characterization under ITER relevant conditions. The tension–tension fatigue test is useful to simulate the pulsed tokamak operation of the ITER coils in the relevant range of 104–105 cycles. The fatigue process can be run under load or strain control,

  4. An iterative Riemann solver for systems of hyperbolic conservation law s, with application to hyperelastic solid mechanics

    SciTech Connect

    Miller, Gregory H.

    2003-08-06

    In this paper we present a general iterative method for the solution of the Riemann problem for hyperbolic systems of PDEs. The method is based on the multiple shooting method for free boundary value problems. We demonstrate the method by solving one-dimensional Riemann problems for hyperelastic solid mechanics. Even for conditions representative of routine laboratory conditions and military ballistics, dramatic differences are seen between the exact and approximate Riemann solution. The greatest discrepancy arises from misallocation of energy between compressional and thermal modes by the approximate solver, resulting in nonphysical entropy and temperature estimates. Several pathological conditions arise in common practice, and modifications to the method to handle these are discussed. These include points where genuine nonlinearity is lost, degeneracies, and eigenvector deficiencies that occur upon melting.

  5. Using a Notion of Safety in Petri Nets To Analyse RealTime Systems

    E-print Network

    Schmidt, Heinz

    Using a Notion of Safety in Petri Nets To Analyse Real­Time Systems Sea Ling and Heinz W. Schmidt 99032787 Fax +61 3 99031077 Email: fsling,hwsg@insect.sd.monash.edu.au (Keywords: Petri nets, real­time explosion in large systems. This problem is compounded in Merlin's Time Petri net (TPN) model [11], in which

  6. Conceptual design description for the tritium recovery system for the US ITER (International Thermonuclear Experimental Reactor) Li sub 2 O\\/Be water cooled blanket

    Microsoft Academic Search

    P. A. Finn; D. K. Sze; R. G. Clemmer

    1990-01-01

    The tritium recovery system for the US ITER LiâO\\/Be water cooled blanket processes two separate helium purge streams to recover tritium from the LiâO zones and the Be zones of the blanket, to process the waste products, and to recirculate the helium back to the blanket. The components are selected to minimize the tritium inventory of the recovery system, and

  7. Conceptual design description for the tritium recovery system for the US ITER Li sub 2 O\\/Be water cooled blanket

    Microsoft Academic Search

    P. A. Finn; D. K. Sze; R. G. Clemmer

    1990-01-01

    The tritium recovery system for the US ITER LiâO\\/Be water cooled blanket processes two separate helium purge streams to recovery tritium from the LiâO zones and the Be zones of the blanket, to process the waste products, and to recirculate the helium back to the blanket. The components are selected to minimize the tritium inventory of the recovery system, and

  8. preparee au Laboratoire d'Analyse et d'Architecture des Syst`emes du CNRS

    E-print Network

    Paris-Sud XI, Université de

    Th`ese pr´epar´ee au Laboratoire d'Analyse et d'Architecture des Syst`emes du CNRS en vue de l and the talks we had together about women. It would be impossible to leave out Sophie Achte, Camille Cazeuneve

  9. The Impact of British Airways Wind Observations on the Goddard Earth Observing System Analyses and Forecasts

    NASA Technical Reports Server (NTRS)

    Rukhovets, Leonid; Sienkiewicz, M.; Tenenbaum, J.; Kondratyeva, Y.; Owens, T.; Oztunali, M.; Atlas, Robert (Technical Monitor)

    2001-01-01

    British Airways flight data recorders can provide valuable meteorological information, but they are not available in real-time on the Global Telecommunication System. Information from the flight recorders was used in the Global Aircraft Data Set (GADS) experiment as independent observations to estimate errors in wind analyses produced by major operational centers. The GADS impact on the Goddard Earth Observing System Data Assimilation System (GEOS DAS) analyses was investigated using GEOS-1 DAS version. Recently, a new Data Assimilation System (fvDAS) has been developed at the Data Assimilation Office, NASA Goddard. Using fvDAS , the, GADS impact on analyses and forecasts was investigated. It was shown the GADS data intensify wind speed analyses of jet streams for some cases. Five-day forecast anomaly correlations and root mean squares were calculated for 300, 500 hPa and SLP for six different areas: Northern and Southern Hemispheres, North America, Europe, Asia, USA These scores were obtained as averages over 21 forecasts from January 1998. Comparisons with scores for control experiments without GADS showed a positive impact of the GADS data on forecasts beyond 2-3 days for all levels at the most areas.

  10. AN END-TO-END SYSTEM FOR MODEL CHECKING OVER CONTEXT-SENSITIVE ANALYSES

    E-print Network

    Pingali, Keshav K.

    systems, Carnauba is capable of checking formulas ranging over the full modal mu-calculus. Further, Car- fication and code comprehension. A context-sensitive analysis is an analysis in which program elements these types of analyses make up the core of interprocedural program analysis and are pervasive, having

  11. Internal Iteration Externalized

    Microsoft Academic Search

    Thomas Kühne

    1999-01-01

    Although it is acknowledged that internal iterators are easier and safer to use than conventional external iterators, it is commonly as- sumed that they are not applicable in languages without builtin support for closures and that they are less flexible than external iterators. We present an iteration framework that uses objects to emulate closures, separates structure exploration and data consumption,

  12. Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts.

    SciTech Connect

    Sevougian, S. David; Freeze, Geoffrey A. [Sandia National Laboratories, Albuquerque, NM; Gardner, William Payton [Sandia National Laboratories, Albuquerque, NM; Hammond, Glenn Edward [Sandia National Laboratories, Albuquerque, NM; Mariner, Paul [Sandia National Laboratories, Albuquerque, NM

    2014-09-01

    directly, rather than through simplified abstractions. It also a llows for complex representations of the source term, e.g., the explicit representation of many individual waste packages (i.e., meter - scale detail of an entire waste emplacement drift). This report fulfills the Generic Disposal System Analysis Work Packa ge Level 3 Milestone - Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts (M 3 FT - 1 4 SN08080 3 2 ).

  13. ASSESSMENT OF THE DCLL TBM THERMOSTRUCTURAL RESPONSE BASED ON ITER DESIGN CRITERIA

    E-print Network

    Ghoniem, Nasr M.

    for ITER In-vessel Components (SDC-IC), which provides rules for the design evaluation and stress analyses of in-vessel mechanical components of ITER with the purpose of ensuring that required safety margins as safety important ITER components, they must fulfill all required ITER codes and standards for reliable

  14. A System and Language for Building System-Specific, Static Analyses

    Microsoft Academic Search

    Seth Hallem; Benjamin Chelf; Yichen Xie; Dawson R. Engler

    2002-01-01

    This paper presents a novel approach to bug-finding analysis and an implementation of that approach. Our goal is to find as many serious bugs as possible. To do so, we designed a flexible, easy-to-use extension language for specifying analyses and an efficent algorithm for executing these extensions. The language, , executes these analyses efficiently using a context-sensitive, interprocedural analysis. Our

  15. Fast Iterative Solver for Convection-Diffusion Systems with Spectral Elements

    E-print Network

    Elman, Howard

    - neered systems such as those involving water, oil, or blood. The interplay between inertial and viscous challenges in situations where the convective nature of the flow dominates diffusive effects. In such flows

  16. A low-complexity linear and iterative receiver architecture for multi-antenna communication systems

    E-print Network

    Milliner, David Louis, 1981-

    2004-01-01

    Multi-antenna systems have been shown to significantly improve channel capacity in wireless environments. The focus of this thesis is on the design of low-complexity multi-antenna receiver architectures for communication ...

  17. DEVELOPMENT AND DEMONSTRATION OF A SUPERCRITICAL HELIUM-COOLED CRYOGENIC VISCOUS COMPRESSOR PROTOTYPE FOR THE ITER VACUUM SYSTEM

    SciTech Connect

    Duckworth, Robert C [ORNL; Baylor, Larry R [ORNL; Meitner, Steven J [ORNL; Combs, Stephen Kirk [ORNL; Rasmussen, David A [ORNL; Edgemon, Timothy D [ORNL; Hechler, Michael P [ORNL; Barbier, Charlotte N [ORNL; Pearce, R.J.H. [ITER Organization, Cadarache, France; Kersevan, R. [ITER Organization, Cadarache, France; Dremel, M. [ITER Organization, Cadarache, France; Boissin, Jean Claude [Consultant

    2012-01-01

    As part of the vacuum system for the ITER fusion project, a cryogenic viscouscompressor (CVC) is being developed to collect hydrogenic exhaust gases from the toruscryopumps and compress them to a high enough pressure by regeneration for pumping tothe tritium reprocessing facility. Helium impurities that are a byproduct of the fusionreactions pass through the CVC and are pumped by conventional vacuum pumps andexhausted to the atmosphere. Before the development of a full-scale CVC, a representative,small-scale test prototype was designed, fabricated, and tested. With cooling provided bycold helium gas, hydrogen gas was introduced into the central column of the test prototypepump at flow rates between 0.001 g/s and 0.008 g/s. Based on the temperatures and flowrates of the cold helium gas, different percentages of hydrogen gas were frozen to the column surface wall as the hydrogen gas flow rate increased. Results from the measured temperatures and pressures will form a benchmark that will be used to judge future heattransfer enhancements to the prototype CVC and to develop a computational fluid dynamicmodel that will help develop design parameters for the full-scale CVC.

  18. The Patient Profile System: Group Health's first iteration of the automated medical record.

    PubMed

    Schoenleber, M D; Elias, S

    1993-06-01

    In 1988, Group Health, Inc., a large staff model HMO in the Twin Cities of Minneapolis and St Paul, MN, began upgrading its computer systems. This provided an opportunity for the organization to begin the development of its first automated medical record, called the Patient Profile System (PPS). This paper describes that effort. Discussed are the design, development, implementation, features and uses of the system. The reader considering a similar endeavor should have an idea of what this development process might entail within the framework of a large HMO. Although not embodying all the features that would be necessary for the fully computerized medical record, the PPS has proved to be a useful clinical tool. Lessons learned from the development and implementation of the PPS will help us reach the goal of fully automating the medical record. PMID:10126684

  19. On iterative approaches for electromagnetic rough-surface scattering problems

    Microsoft Academic Search

    James C. West; J. Michael Sturm

    1999-01-01

    Iterative techniques developed for solving general systems of linear equations have been applied to systems resulting from electromagnetic rough-surface scattering problems. Previously used iterative procedures that model the multiple scattering of the electromagnetic energy are shown to be mathematically equivalent to the application of stationary iterative procedures to the system of equations resulting from the standard moment method. Convergence difficulties

  20. New iterative algorithm for algebraic Riccati equation related to H ? control problem of singularly perturbed systems

    Microsoft Academic Search

    Hiroaki Mukaidani; Hua Xu; Koichi Mizukami

    2001-01-01

    We present the solution to the algebraic Riccati equation (ARE) with indefinite sign quadratic term related to the H? control problem for singularly perturbed systems by means of a Kleinman type algorithm. The resulting algorithm is very efficient from the numerical point of view because the ARE is solvable even if the quadratic term has an indefinite sign. Moreover, the

  1. Preliminary safety analysis for the Chinese ITER Dual Functional Lithium-Lead Test Blanket Module

    NASA Astrophysics Data System (ADS)

    Chen, Hongli; Bai, Yunqing; Hu, Liqin; Chen, Mingliang; Song, Yong; Zeng, Qin; Liu, Songlin

    2009-07-01

    Safety analysis is part of the ITER Test Blanket Module (TBM) design process ensuring that the TBM does not adversely affect the safety of ITER. To get the licence for TBM as a whole with ITER, relevant safety analysis is required for each TBM system proposed by each party. The safety analysis for the Chinese Dual Functional Lithium-Lead Test Blanket Module (DFLL-TBM) has been performed based on the latest DFLL-TBM design. In this paper, the following safety considerations, such as source terms, operational releases, accident sequence analyses and waste assessment, were analysed. Both the deterministic approach and the complementary systematic approach starting with failure mode and effects analysis studies were adopted in the accidental analysis. The preliminary results showed that the DFLL-TBM system at normal operating conditions and under accident scenarios did not add additional safety hazards to the ITER machine and could meet the ITER safety requirements and additional safety requirements for the TBM system.

  2. Space transfer concepts and analyses for exploration missions. Technical directive 12: Beamed power systems study

    NASA Technical Reports Server (NTRS)

    Eder, D.

    1992-01-01

    Parametric models were constructed for Earth-based laser powered electric orbit transfer from low Earth orbit to geosynchronous orbit. These models were used to carry out performance, cost/benefit, and sensitivity analyses of laser-powered transfer systems including end-to-end life cycle cost analyses for complete systems. Comparisons with conventional orbit transfer systems were made indicating large potential cost savings for laser-powered transfer. Approximate optimization was done to determine best parameter values for the systems. Orbit transfer flights simulations were conducted to explore effects of parameters not practical to model with a spreadsheet. The simulations considered view factors that determine when power can be transferred from ground stations to an orbit transfer vehicle and conducted sensitivity analyses for numbers of ground stations, Isp including dual-Isp transfers, and plane change profiles. Optimal steering laws were used for simultaneous altitude and plane change. Viewing geometry and low-thrust orbit raising were simultaneously simulated. A very preliminary investigation of relay mirrors was made.

  3. A program system for ab initio MO calculations on vector and parallel processing machines II. SCF closed-shell and open-shell iterations

    Microsoft Academic Search

    Marie-Madeleine Rohmer; Jean Demuynck; Marc Bénard; Roland Wiest; Christian Bachmann; Charles Henriet; René Ernenwein

    1990-01-01

    This series of three papers presents a program system for ab initio molecular orbital calculations on vector and parallel computers. Part II is devoted to SCF iterations on closed-shell and open-shell configurations starting from a file of two-electron integrals on the basis of contracted Gaussians (CGTOs). In a preliminary step, the two-electron integrals (pqrs) are reordered according to increasing values

  4. Joint iterative power allocation and relay selection for cooperative MIMO systems using discrete stochastic algorithms

    Microsoft Academic Search

    Patrick Clarke; Rodrigo C. de Lamare

    2011-01-01

    In this work, we propose a set of joint power allocation and relay selection (RS) algorithms for multi-relay cooperative multiple-input-multiple-output (MIMO) systems. Adaptive discrete stochastic algorithms (DSA) are used to generate a subset of relays over which stochastic gradient continuous power allocation operates. Optimum minimum mean-square error (MMSE) and adaptive reception are considered in a decode-and-forward (DF) network with a

  5. Systematic Redundant Residue Number System Codes: Analytical Upper Bound and Iterative Decoding Performance Over AWGN and

    Microsoft Academic Search

    Rayleigh Channels; T. H. Liew; Lie-Liang Yang; Lajos Hanzo

    2006-01-01

    The novel family of redundant residue number system (RRNS) codes is studied. RRNS codes constitute max- imum-minimum distance block codes, exhibiting identical distance properties to Reed-Solomon codes. Binary to RRNS symbol-mapping methods are proposed, in order to implement both systematic and nonsystematic RRNS codes. Furthermore, the upper-bound performance of systematic RRNS codes is inves- tigated, when maximum-likelihood (ML) soft decoding

  6. Upper bounds for convergence rates of vector extrapolation methods on linear systems with initial iterations. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Sidi, Avram; Shapira, Yair

    1992-01-01

    The application of the minimal polynomial extrapolation (MPE) and the reduced rank extrapolation (RRE) to a vector sequence obtained by the linear iterative technique x(sub j) + 1 = Ax(sub j) = b,j = 1,2,..., is considered. Both methods produce a two dimensional array of approximations s(sub n,k) to the solution of the system (I - A)x = b. Here, s(sub n,k) is obtained from the vectors x(sub j), n is less than or equal to j is less than or equal to n + k + 1. It was observed in an earlier publication by the first author that the sequence s(sub n,k), k = 1,2,..., for n greater than 0, but fixed, possesses better convergence properties than the sequence s(sub 0,k), k = 1,2,.... A detailed theoretical explanation for this phenomenon is provided in the present work. This explanation is heavily based on approximations by incomplete polynomials. It is demonstrated by numerical examples when the matrix A is sparse that cycling with s(sub n,k) for n greater than 0, but fixed, produces better convergence rates and costs less computationally than cycling with s(sub 0,k). It is also illustrated numerically with a convection-diffusion problem that the former may produce excellent results where the latter may fail completely. As has been shown in an earlier publication, the results produced by s(sub 0,k) are identical to the corresponding results obtained by applying the Arnoldi method or generalized minimal residual scheme (GMRES) to the system (I - A)x = b.

  7. System Evaluations and Life-Cycle Cost Analyses for High-Temperature Electrolysis Hydrogen Production Facilities

    Microsoft Academic Search

    Edwin A. Harvego; James E. OBrien; Michael G. McKellar

    2012-01-01

    This report presents results of system evaluations and lifecycle cost analyses performed for several different commercial-scale high-temperature electrolysis (HTE) hydrogen production concepts. The concepts presented in this report rely on grid electricity and non-nuclear high-temperature process heat sources for the required energy inputs. The HYSYS process analysis software was used to evaluate both central plant designs for large-scale hydrogen production

  8. A rad-hard, steady state, digital imaging bolometer system for ITER

    SciTech Connect

    Wurden, G.A.

    1995-09-01

    The concept and design of a new type of bolometer system which can function with excellent spatial resolution and good time resolution in the next generation of long-pulse (or steady-state), harsh-neutron environment fusion plasmas, is outlined. It uses a cooled pinhole camera design, employing a robust, passive, segmented radiation absorber, cooled from the back-side. Infrared emission from the absorber`s front surface is relayed by metal mirror optics to a shielded, high-resolution IR video camera with {+-} 0.01 C temperature resolution. It can make thousands of simultaneous ``pixel`` measurements at up to 50--60 Hz, without any signal wires through the vacuum interface.

  9. Analyses of the dynamic docking test system for advanced mission docking system test programs. [Apollo Soyuz Test Project

    NASA Technical Reports Server (NTRS)

    Gates, R. M.; Williams, J. E.

    1974-01-01

    Results are given of analytical studies performed in support of the design, implementation, checkout and use of NASA's dynamic docking test system (DDTS). Included are analyses of simulator components, a list of detailed operational test procedures, a summary of simulator performance, and an analysis and comparison of docking dynamics and loads obtained by test and analysis.

  10. Extraterrestrial Materials: The Role of Synchrotron Radiation Analyses in the Study of our Solar System

    SciTech Connect

    Sutton, Stephen R. [University of Chicago

    2006-04-05

    Sample-return missions and natural collection processes have provided us with a surprisingly extensive collection of matter from Solar System bodies other than the Earth. These collections include samples from the Moon, Mars, asteroids, interplanetary dust, and, recently, from the Sun (solar wind) and a comet. This presentation will describe some of these materials, how they were collected, and what we have learned from them. Synchrotron radiation analyses of these materials are playing an increasingly valuable role in unraveling the histories and properities of the parent Solar System bodies.

  11. Evaluation of Clipping Based Iterative PAPR Reduction Techniques for FBMC Systems

    PubMed Central

    Kollár, Zsolt

    2014-01-01

    This paper investigates filter bankmulticarrier (FBMC), a multicarrier modulation technique exhibiting an extremely low adjacent channel leakage ratio (ACLR) compared to conventional orthogonal frequency division multiplexing (OFDM) technique. The low ACLR of the transmitted FBMC signal makes it especially favorable in cognitive radio applications, where strict requirements are posed on out-of-band radiation. Large dynamic range resulting in high peak-to-average power ratio (PAPR) is characteristic of all sorts of multicarrier signals. The advantageous spectral properties of the high-PAPR FBMC signal are significantly degraded if nonlinearities are present in the transceiver chain. Spectral regrowth may appear, causing harmful interference in the neighboring frequency bands. This paper presents novel clipping based PAPR reduction techniques, evaluated and compared by simulations and measurements, with an emphasis on spectral aspects. The paper gives an overall comparison of PAPR reduction techniques, focusing on the reduction of the dynamic range of FBMC signals without increasing out-of-band radiation. An overview is presented on transmitter oriented techniques employing baseband clipping, which can maintain the system performance with a desired bit error rate (BER). PMID:24558338

  12. Evaluation of clipping based iterative PAPR reduction techniques for FBMC systems.

    PubMed

    Kollár, Zsolt; Varga, Lajos; Horváth, Bálint; Bakki, Péter; Bitó, János

    2014-01-01

    This paper investigates filter bankmulticarrier (FBMC), a multicarrier modulation technique exhibiting an extremely low adjacent channel leakage ratio (ACLR) compared to conventional orthogonal frequency division multiplexing (OFDM) technique. The low ACLR of the transmitted FBMC signal makes it especially favorable in cognitive radio applications, where strict requirements are posed on out-of-band radiation. Large dynamic range resulting in high peak-to-average power ratio (PAPR) is characteristic of all sorts of multicarrier signals. The advantageous spectral properties of the high-PAPR FBMC signal are significantly degraded if nonlinearities are present in the transceiver chain. Spectral regrowth may appear, causing harmful interference in the neighboring frequency bands. This paper presents novel clipping based PAPR reduction techniques, evaluated and compared by simulations and measurements, with an emphasis on spectral aspects. The paper gives an overall comparison of PAPR reduction techniques, focusing on the reduction of the dynamic range of FBMC signals without increasing out-of-band radiation. An overview is presented on transmitter oriented techniques employing baseband clipping, which can maintain the system performance with a desired bit error rate (BER). PMID:24558338

  13. TES microcalorimeter SEM-EDS system for rare-earth elements analyses

    NASA Astrophysics Data System (ADS)

    Uehara, Seiichiro; Takai, Yasuhiro; Shirose, Yohei; Fujii, Yuki

    A field-emission scanning electron microscope (FE-SEM) with energy-dispersive X-ray spectrometer (EDS) detector of a superconducting transition-edge sensor (TES) microcalorimeter is a new system for electron-microprobe chemical analyses. FE-SEM with TES was used for qualitative and semi-quantitative analyses of rare-earth elements (REE) at a low accelerating voltage of 5 kV. Four characteristic M-lines were detected in the LaB6 spectrum: LaM? at 640, LaM?? at 841, LaM? at 1021, and a weak line (M2N4 transition) at 1100 eV. The spectra of other rare-earth borides, rare-earth phosphates, and monazite were assigned in the same way as the La M-lines were. For quantitative analyses, we used a calibration curve method, using standard specimens of known chemical compositions. Linear calibration curves for plots of P, Ca, La, Ce, Pr, and Nd intensities versus each weight percentage were obtained. Semi-quantitative analyses of rare-earth minerals should be carried out at low accelerating voltages using a calibration curve method. In a TES-EDS system, a low accelerating voltage can be used to improve the spatial resolution, without the sensitivity disadvantages of low-energy X-ray emissions. Moreover, a strong increase in the M?? intensity with increasing atomic number Z was seen, so the detection limits of heavy REE was much lower than those of light REEs. These results suggest that the TES-EDS system could be a useful analytical tool in rare-earth mineralogy.

  14. Integrated Process Model Development and Systems Analyses for the LIFE Power Plant

    SciTech Connect

    Meier, W R; Anklam, T; Abbott, R; Erlandson, A; Halsey, W; Miles, R; Simon, A J

    2009-07-15

    We have developed an integrated process model (IPM) for a Laser Inertial Fusion-Fission Energy (LIFE) power plant. The model includes cost and performance algorithms for the major subsystems of the plant, including the laser, fusion target fabrication and injection, fusion-fission chamber (including the tritium and fission fuel blankets), heat transfer and power conversion systems, and other balance of plant systems. The model has been developed in Visual Basic with an Excel spreadsheet user interface in order to allow experts in various aspects of the design to easily integrate their individual modules and provide a convenient, widely accessible platform for conducting the system studies. Subsystem modules vary in level of complexity; some are based on top-down scaling from fission power plant costs (for example, electric plant equipment), while others are bottom-up models based on conceptual designs being developed by LLNL (for example, the fusion-fission chamber and laser systems). The IPM is being used to evaluate design trade-offs, do design optimization, and conduct sensitivity analyses to identify high-leverage areas for R&D. We describe key aspects of the IPM and report on the results of our systems analyses. Designs are compared and evaluated as a function of key design variables such as fusion target yield and pulse repetition rate.

  15. An evaluation system for electronic retrospective analyses in radiation oncology: implemented exemplarily for pancreatic cancer

    NASA Astrophysics Data System (ADS)

    Kessel, Kerstin A.; Jäger, Andreas; Bohn, Christian; Habermehl, Daniel; Zhang, Lanlan; Engelmann, Uwe; Bougatf, Nina; Bendl, Rolf; Debus, Jürgen; Combs, Stephanie E.

    2013-03-01

    To date, conducting retrospective clinical analyses is rather difficult and time consuming. Especially in radiation oncology, handling voluminous datasets from various information systems and different documentation styles efficiently is crucial for patient care and research. With the example of patients with pancreatic cancer treated with radio-chemotherapy, we performed a therapy evaluation by using analysis tools connected with a documentation system. A total number of 783 patients have been documented into a professional, web-based documentation system. Information about radiation therapy, diagnostic images and dose distributions have been imported. For patients with disease progression after neoadjuvant chemoradiation, we designed and established an analysis workflow. After automatic registration of the radiation plans with the follow-up images, the recurrence volumes are segmented manually. Based on these volumes the DVH (dose-volume histogram) statistic is calculated, followed by the determination of the dose applied to the region of recurrence. All results are stored in the database and included in statistical calculations. The main goal of using an automatic evaluation system is to reduce time and effort conducting clinical analyses, especially with large patient groups. We showed a first approach and use of some existing tools, however manual interaction is still necessary. Further steps need to be taken to enhance automation. Already, it has become apparent that the benefits of digital data management and analysis lie in the central storage of data and reusability of the results. Therefore, we intend to adapt the evaluation system to other types of tumors in radiation oncology.

  16. System modeling, sampling, interpolation and iterative reconstruction for the 3D Compton SPECT camera

    NASA Astrophysics Data System (ADS)

    Sauve, Anne C.

    2000-10-01

    In the past twenty five years, efforts have been made to develop Compton Single Photon Emission Computed Tomography (SPECT) cameras for medical imaging. The Compton camera consists of a pair of position sensitive detectors, a Compton scatter detector and a detector to absorb the scattered photons. The energy and position information from these detectors gives information about the energy, position, and incident direction of the incoming gamma-ray. This "electronic" collimation is superior to conventional mechanical collimation since it utilizes as many emitted photons as possible from all directions, improves the solid angle of detection and therefore provides improved detection efficiency and increased sensitivity. Better sensitivity will have a positive impact on image noise and resolution. Development of practical Compton SPECT faces many new challenges. First, Compton SPECT acquires the projection data directly in 3D and requires storage of three sets of coordinates, two spatial coordinates and the angular coordinates. Therefore Compton SPECT cameras have to deal with very large amount of data leading to difficulties in computation. Hence, simplification of Compton SPECT camera is necessary. Second, new reconstruction methods need to be developed for the Compton SPECT conical projection geometry. This dissertation presents a method for reducing storage and computation which is based on an analytical model that has the potential to permit tractable fully 3D reconstructions. A mathematical model is proposed for the camera which exploits hemispherical symmetries by using an adapted spatial sampling pattern in the object domain. For each projection angle, the sampling pattern is uniform over a set of equispaced nested hemispheres. By using this sampling pattern the system matrix is reduced to a product of an (approximately) block circulant matrix and a sparse interpolation matrix. This representation reduces the very high storage and computation requirement inherent to 3D reconstruction. We consider a simple method for designing the detector pair trajectory around the field of view using a sinogram sampling diagram to guarantee proper object sampling. As the exploitation of hemispherical symmetries requires interpolation, we develop a 3D volumetric interpolation between hemispherical and cartesian coordinates. Finally, we present a 3D image reconstruction method using the 2D Fourier transform for which there exists a fast algorithm because of the block circulant structure of the transition matrix. These methods are simply illustrated for the noiseless case with implementation of a fully 3D penalized least squares reconstruction algorithm.

  17. Real-Time Soils Characterization and Analyses Systems Used at Ohio Closure Sites

    SciTech Connect

    Roybal, Lyle Gene; Carpenter, Michael Vance; Giles, John Robert; Hartwell, John Kelvin; Danahy, R.

    2003-02-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) and the Fernald Environmental Management Project (FEMP) have jointly developed a field-deployed analytical system to rapidly scan, characterize, and analyze surface soil contamination. The basic system consists of a sodium iodide (NaI) spectrometer and global positioning system (GPS) hardware. This hardware can be deployed from any of four different platforms depending on the scope of the survey at hand. These platforms range from a large tractor-based unit (the RTRAK) used to survey large, relatively flat areas to a hand-pushed unit where maneuverability is important, to an excavator mounted system used to scan pits and trenches. The mobile sodium iodide concept was initially developed by the FEMP to provide pre-screening analyses for soils contaminated with uranium, thorium, and radium. The initial study is documented in the RTRAK Applicability Study and provides analyses supporting the field usage of the concept. The RTRAK system produced data that required several days of post-processing and analyses to generate an estimation of field coverage and activity levels. The INEEL has provided integrated engineering, computer hardware and software support to greatly streamline the data acquisition and analysis process to the point where real-time activity and coverage maps are available to the field technicians. On-line analyses have been added to automatically convert GPS data to Ohio State-Plane coordinates, examine and correct collected spectra for energy calibration drifts common to NaI spectrometers, and strip spectra in regions of interest to provide moisture corrected activity levels for total uranium, thorium-232, and radium-226. Additionally, the software provides a number of checks and alarms to alert operators that a hand-examination of spectral data in a particular area may be required. The FEMP has estimated that this technology has produced projected site savings in excess of $34M through FY 2006. Additionally, the INEEL has applied this real-time concept to develop an in-situ platform to detect plutonium-238 in contaminated soils to the 50 pCi/g level. The heart of this system is a large-area proportional counter that collects spectra in the x-ray region. A prototype system was demonstrated at the Mound Environmental Management Project (MEMP) in October of 2002.

  18. Solar power satellite system definition study. Volume 2, phase 1: Systems analyses tradeoffs.

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A systems definition study of the solar power satellite system is presented. The satellite solar energy conversion and microwave power transmission systems are discussed. Space construction and support systems are examined including a series construction and equipment characteristics analysis. Space transportation for the satellite and the ground receiving station are assessed.

  19. Solar power satellite system definition study. Volume 7, phase 1: SPS and rectenna systems analyses

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A systems definition study of the solar power satellite systems is presented. The design and power distribution of the rectenna system is discussed. The communication subsystem and thermal control characteristics are described and a failure analysis performed on the systems is reported.

  20. Manned systems utilization analysis (study 2.1). Volume 3: LOVES computer simulations, results, and analyses

    NASA Technical Reports Server (NTRS)

    Stricker, L. T.

    1975-01-01

    The LOVES computer program was employed to analyze the geosynchronous portion of the NASA's 1973 automated satellite mission model from 1980 to 1990. The objectives of the analyses were: (1) to demonstrate the capability of the LOVES code to provide the depth and accuracy of data required to support the analyses; and (2) to tradeoff the concept of space servicing automated satellites composed of replaceable modules against the concept of replacing expendable satellites upon failure. The computer code proved to be an invaluable tool in analyzing the logistic requirements of the various test cases required in the tradeoff. It is indicated that the concept of space servicing offers the potential for substantial savings in the cost of operating automated satellite systems.

  1. The Global/Local Nexus in Comparative Policy Studies: Analysing the Triple Bonus System in Mongolia over Time

    ERIC Educational Resources Information Center

    Steiner-Khamsi, Gita

    2012-01-01

    The article analyses a phenomenon that has accompanied teacher salary reform in Mongolia: the import of two global education policies that were nearly identical to the already existing local bonus system ("olympiads"). To make sense of an import that appears superfluous, the author analyses the reception and translation of the triple bonus system

  2. Robust fault diagnosis for a satellite large angle attitude system using an iterative neuron PID (INPID) observer

    Microsoft Academic Search

    Qing Wu; Mehrdad Saif

    2006-01-01

    A fault detection and diagnosis (FDD) scheme using an iterative neuron PID (INPID) observer is explored in this paper. The observer input, which is used to estimate state faults, is computed by utilizing the proportional, integral, and derivative information of the fault estimation error. Two classes of robust adaptive algorithms are adopted to update the parameters of the observer input.

  3. ITER Engineering Design Activities -DesignITER-Central Solenoid

    E-print Network

    Maximum inner dimensions 28 m diameter, 24 m height Material SS 304L Heat Transfer Systems (water Plug (EC Heating) Torus Cryopump Divertor Main Engineering Features of ITER Superconducting Toroidal Field Coils (18 coils) Superconductor Nb3Sn in circular stainless steel (SS) jacket in grooved radial

  4. Analyses of heat isolation property for metallic multiwall thermal protection system

    NASA Astrophysics Data System (ADS)

    Sumi, Seinosuke; Murozono, Masahiko; Kushiki, Kenichi; Kusakabe, Masayuki

    1991-08-01

    Transient thermal analyses were carried out for a multiwall titanium thermal protection system (TPS) for the space transportation system, which consists of alternate flat and dimpled sheets which are welded together at the crests of the dimpled sheet, and formed into square tiles which are mechanically attached to the primary structure of the space transportation system. Three modes of heat transfer are considered: (1) conduction through the gas inside the tiles, (2) conduction through the metal, and (3) radiation between the adjoined sheets. Results of a steady state analysis of the three modes of heat transfer yield an effective thermal conductivity. The contributions of each mode of heat transfer to various parameters are shown.

  5. Scenario evolution: Interaction between event tree construction and numerical analyses

    SciTech Connect

    Barr, G.E.; Barnard, R.W.; Dockery, H.A.; Dunn, E. [Sandia National Labs., Albuquerque, NM (USA); MacIntyre, A.T. [Lawrence Livermore National Lab., CA (USA)

    1990-12-31

    Construction of well-posed scenarios for the range of conditions possible at any proposed repository site is a critical first step to assessing total system performance. Event tree construction is the method that is being used to develop potential failure scenarios for the proposed nuclear waste repository at Yucca Mountain. An event tree begins with an initial event or condition. Subsequent events are listed in a sequence, leading eventually to release of radionuclides to the accessible environment. Ensuring the validity of the scenarios requires iteration between problems constructed using scenarios contained in the event tree sequence, experimental results, and numerical analyses. Details not adequately captured within the tree initially may become more apparent as a result of analyses. To illustrate this process, the authors discuss the iterations used to develop numerical analyses for PACE-90 (Performance Assessment Calculational Exercises) using basaltic igneous activity and human-intrusion event trees.

  6. Water-cooled solid-breeder blanket concept for ITER

    SciTech Connect

    Gohar, Y.; Baker, C.C.; Attaya, H.; Billone, M.; Clemmer, R.C.; Finn, P.A.; Hassanein, A.; Johnson, C.E.; Majumdar, S.; Mattas, R.F.

    1989-03-01

    A water cooled solid-breeder blanket concept was developed for ITER. The main function of this blanket is to produce the necessary tritium for the ITER operation. Several design features are incorporated in this blanket concept to increase its attractiveness. The main features are the following: (a) a multilayer concept which reduces fabrication cost; (b) a simple blanket configuration which results in reliability advantages; (c) a very small breeder volume is employed to reduce the tritium inventory and the blanket cost; (d) a high tritium breeding ratio eliminates the need for an outside tritium supply; (e) a low-pressure system decreases the required steel fraction for structural purposes; (f) a low-temperature operation reduces the swelling concerns for beryllium; and (g) the small fractions of structure and breeder materials used in the blanket reduce the decay heat source. The key features and design analyses of this blanket are summarized in this paper.

  7. ITER LHCD Plans and Design

    Microsoft Academic Search

    Ph. Bibet; B. Beaumont; J. H. Belo; J. P. S. Bizarro; L. Delpech; A. Ekedahl; G. Granucci; F. Kazarian; S. Kuzikov; X. Litaudon; J. Mailloux; F. Mirizzi; V. Pericoli; M. Prou; K. Rantamaki; A. A. Tuccillo

    2005-01-01

    LH waves experimentally exhibit the highest current drive efficiency at low plasma temperature, therefore they are the most suitable candidates for controlling the current profile in the off axis part of ITER steady state plasmas. For this purpose, a 5 GHz, 20 MW CW LH system has been designed, that relies on a generator made of 24 klystrons, 1 MW

  8. The Predicted Arabidopsis Interactome Resource and Network Topology-Based Systems Biology Analyses[W][OA

    PubMed Central

    Lin, Mingzhi; Zhou, Xi; Shen, Xueling; Mao, Chuanzao; Chen, Xin

    2011-01-01

    Predicted interactions are a valuable complement to experimentally reported interactions in molecular mechanism studies, particularly for higher organisms, for which reported experimental interactions represent only a small fraction of their total interactomes. With careful engineering consideration of the lessons from previous efforts, the Predicted Arabidopsis Interactome Resource (PAIR; ) presents 149,900 potential molecular interactions, which are expected to cover ~24% of the entire interactome with ~40% precision. This study demonstrates that, although PAIR still has limited coverage, it is rich enough to capture many significant functional linkages within and between higher-order biological systems, such as pathways and biological processes. These inferred interactions can nicely power several network topology-based systems biology analyses, such as gene set linkage analysis, protein function prediction, and identification of regulatory genes demonstrating insignificant expression changes. The drastically expanded molecular network in PAIR has considerably improved the capability of these analyses to integrate existing knowledge and suggest novel insights into the function and coordination of genes and gene networks. PMID:21441435

  9. Battery-powered portable instrument system for single-cell trapping, impedance measurements, and modeling analyses.

    PubMed

    Tsai, Sung-Lin; Chiang, Yang; Wang, Min-Haw; Chen, Ming-Kun; Jang, Ling-Sheng

    2014-08-01

    A battery-powered portable instrument system for the single-HeLa-cell trapping and analyses is developed. A method of alternating current electrothermal (ACET) and DEP are employed for the cell trapping and the method of impedance spectroscopy is employed for cell characterizations. The proposed instrument (160 mm × 170 mm × 110 mm, 1269 g) equips with a highly efficient energy-saving design that promises approximately 120 h of use. It includes an impedance analyzer performing an excitation voltage of 0.2-2 Vpp and a frequency sweep of 11-101 kHz, function generator with the sine wave output at an operating voltage of 1-50 Vpp with a frequency of 4-12 MHz, cell-trapping biochip, microscope, and input/output interface. The biochip for the single cell trapping is designed and simulated based on a combination of ACET and DEP forces. In order to improve measurement accuracy, the curve fitting method is adopted to calibrate the proposed impedance spectroscopy. Measurement results from the proposed system are compared with results from a precision impedance analyzer. The trapped cell can be modeled for numerical analyses. Many advantages are offered in the proposed instrument such as the small volume, real-time monitoring, rapid analysis, low cost, low-power consumption, and portable application. PMID:24610717

  10. Preparing ITER ICRF: development and analysis of the load resilient matching systems based on antenna mock-up measurements

    NASA Astrophysics Data System (ADS)

    Messiaen, A.; Vervier, M.; Dumortier, P.; Grine, D.; Lamalle, P. U.; Durodié, F.; Koch, R.; Louche, F.; Weynants, R.

    2009-05-01

    The reference design for the ICRF antenna of ITER is constituted by a tight array of 24 straps grouped in eight triplets. The matching network must be load resilient for operation in ELMy discharges and must have antenna spectrum control for heating or current drive operation. The load resilience is based on the use of either hybrid couplers or conjugate-T circuits. However, the mutual coupling between the triplets at the low expected loading strongly counteracts the load resilience and the spectrum control. Using a mock-up of the ITER antenna array with adjustable water load matching solutions are designed. These solutions are derived from transmission line modelling based on the measured scattering matrix and are finally tested. We show that the array current spectrum can be controlled by the anti-node voltage distribution and that suitable decoupler circuits can not only neutralize the adverse mutual coupling effects but also monitor this anti-node voltage distribution. A matching solution using four 3 dB hybrids and the antenna current spectrum feedback control by the decouplers provides outstanding performance if each pair of poloidal triplets undergoes a same load variation. Finally, it is verified by modelling that this matching scenario has the same antenna spectrum and load resilience performances as the antenna array loaded by plasma as described by the TOPICA simulation. This is true for any phasing and frequency in the ITER frequency band. The conjugate-T solution is presently considered as a back-up option.

  11. On the safety of ITER accelerators

    PubMed Central

    Li, Ge

    2013-01-01

    Three 1?MV/40A accelerators in heating neutral beams (HNB) are on track to be implemented in the International Thermonuclear Experimental Reactor (ITER). ITER may produce 500?MWt of power by 2026 and may serve as a green energy roadmap for the world. They will generate ?1?MV 1?h long-pulse ion beams to be neutralised for plasma heating. Due to frequently occurring vacuum sparking in the accelerators, the snubbers are used to limit the fault arc current to improve ITER safety. However, recent analyses of its reference design have raised concerns. General nonlinear transformer theory is developed for the snubber to unify the former snubbers' different design models with a clear mechanism. Satisfactory agreement between theory and tests indicates that scaling up to a 1?MV voltage may be possible. These results confirm the nonlinear process behind transformer theory and map out a reliable snubber design for a safer ITER. PMID:24008267

  12. On the safety of ITER accelerators.

    PubMed

    Li, Ge

    2013-01-01

    Three 1 MV/40A accelerators in heating neutral beams (HNB) are on track to be implemented in the International Thermonuclear Experimental Reactor (ITER). ITER may produce 500 MWt of power by 2026 and may serve as a green energy roadmap for the world. They will generate -1 MV 1 h long-pulse ion beams to be neutralised for plasma heating. Due to frequently occurring vacuum sparking in the accelerators, the snubbers are used to limit the fault arc current to improve ITER safety. However, recent analyses of its reference design have raised concerns. General nonlinear transformer theory is developed for the snubber to unify the former snubbers' different design models with a clear mechanism. Satisfactory agreement between theory and tests indicates that scaling up to a 1 MV voltage may be possible. These results confirm the nonlinear process behind transformer theory and map out a reliable snubber design for a safer ITER. PMID:24008267

  13. Time series analyses of breathing patterns of lung cancer patients using nonlinear dynamical system theory

    NASA Astrophysics Data System (ADS)

    Tewatia, D. K.; Tolakanahalli, R. P.; Paliwal, B. R.; Tomé, W. A.

    2011-04-01

    The underlying requirements for successful implementation of any efficient tumour motion management strategy are regularity and reproducibility of a patient's breathing pattern. The physiological act of breathing is controlled by multiple nonlinear feedback and feed-forward couplings. It would therefore be appropriate to analyse the breathing pattern of lung cancer patients in the light of nonlinear dynamical system theory. The purpose of this paper is to analyse the one-dimensional respiratory time series of lung cancer patients based on nonlinear dynamics and delay coordinate state space embedding. It is very important to select a suitable pair of embedding dimension 'm' and time delay '?' when performing a state space reconstruction. Appropriate time delay and embedding dimension were obtained using well-established methods, namely mutual information and the false nearest neighbour method, respectively. Establishing stationarity and determinism in a given scalar time series is a prerequisite to demonstrating that the nonlinear dynamical system that gave rise to the scalar time series exhibits a sensitive dependence on initial conditions, i.e. is chaotic. Hence, once an appropriate state space embedding of the dynamical system has been reconstructed, we show that the time series of the nonlinear dynamical systems under study are both stationary and deterministic in nature. Once both criteria are established, we proceed to calculate the largest Lyapunov exponent (LLE), which is an invariant quantity under time delay embedding. The LLE for all 16 patients is positive, which along with stationarity and determinism establishes the fact that the time series of a lung cancer patient's breathing pattern is not random or irregular, but rather it is deterministic in nature albeit chaotic. These results indicate that chaotic characteristics exist in the respiratory waveform and techniques based on state space dynamics should be employed for tumour motion management.

  14. Property Changes of Cyanate Ester/epoxy Insulation Systems Caused by AN Iter-Like Double Impregnation and by Reactor Irradiation

    NASA Astrophysics Data System (ADS)

    Prokopec, R.; Humer, K.; Fillunger, H.; Maix, R. K.; Weber, H. W.

    2010-04-01

    Because of the double pancake design of the ITER TF coils the insulation will be applied in several steps. As a consequence, the conductor insulation as well as the pancake insulation will undergo multiple heat cycles in addition to the initial curing cycle. In particular the properties of the organic resin may be influenced, since its heat resistance is limited. Two identical types of sample consisting of wrapped R-glass/Kapton layers and vacuum impregnated with a cyanate ester/epoxy blend were prepared. The build-up of the reinforcement was identical for both insulation systems; however, one system was fabricated in two steps. In the first step only one half of the reinforcing layers was impregnated and cured. Afterwards the remaining layers were wrapped onto the already cured system, before the resulting system was impregnated and cured again. The mechanical properties were characterized prior to and after irradiation to fast neutron fluences of 1 and 2×1022 m-2 (E>0.1 MeV) in tension and interlaminar shear at 77 K. In order to simulate the pulsed operation of ITER, tension-tension fatigue measurements were performed in the load controlled mode. The results do not show any evidence for reduced mechanical strength caused by the additional heat cycle.

  15. PROPERTY CHANGES OF CYANATE ESTER/EPOXY INSULATION SYSTEMS CAUSED BY AN ITER-LIKE DOUBLE IMPREGNATION AND BY REACTOR IRRADIATION

    SciTech Connect

    Prokopec, R.; Humer, K.; Fillunger, H.; Maix, R. K.; Weber, H. W. [Atominstitut, Vienna University of Technology, 1020 Wien (Austria)

    2010-04-08

    Because of the double pancake design of the ITER TF coils the insulation will be applied in several steps. As a consequence, the conductor insulation as well as the pancake insulation will undergo multiple heat cycles in addition to the initial curing cycle. In particular the properties of the organic resin may be influenced, since its heat resistance is limited. Two identical types of sample consisting of wrapped R-glass/Kapton layers and vacuum impregnated with a cyanate ester/epoxy blend were prepared. The build-up of the reinforcement was identical for both insulation systems; however, one system was fabricated in two steps. In the first step only one half of the reinforcing layers was impregnated and cured. Afterwards the remaining layers were wrapped onto the already cured system, before the resulting system was impregnated and cured again. The mechanical properties were characterized prior to and after irradiation to fast neutron fluences of 1 and 2x10{sup 22} m{sup -2}(E>0.1 MeV) in tension and interlaminar shear at 77 K. In order to simulate the pulsed operation of ITER, tension-tension fatigue measurements were performed in the load controlled mode. The results do not show any evidence for reduced mechanical strength caused by the additional heat cycle.

  16. The real mission of ITER

    SciTech Connect

    Wurden, G A [Los Alamos National Laboratory

    2009-01-01

    For future machines, the plasma stored energy is going up by factors of 20-40x, and plasma currents by 2-3x, while the surface to volume ratio is at the same time decreasing. Therefore the disruption forces, even for constant B, (which scale like IxB), and associated possible localized heating on machine components, are more severe. Notably, Tore Supra has demonstrated removal of more than 1 GJ of input energy, over nearly a 400 second period. However, the instantaneous stored energy in the Tore Supra system (which is most directly related to the potential for disruption damage) is quite small compared to other large tokamaks. The goal of ITER is routinely described as studying DT burning plasmas with a Q {approx} 10. In reality, ITER has a much more important first order mission. In fact, if it fails at this mission, the consequences are that ITER will never get to the eventual stated purpose of studying a burning plasma. The real mission of ITER is to study (and demonstrate successfully) plasma control with {approx}10-17 MA toroidal currents and {approx}100-400 MJ plasma stored energy levels in long-pulse scenarios. Before DT operation is ever given a go-ahead in ITER, the reality is that ITER must demonstrate routine and reliable control of high energy hydrogen (and deuterium) plasmas. The difficulty is that ITER must simultaneously deal with several technical problems: (1) heat removal at the plasma/wall interface, (2) protection of the wall components from off-normal events, and (3) generation of dust/redeposition of first wall materials. All previous tokamaks have encountered hundred's of major disruptions in the course of their operation. The consequences of a few MA of runaway electrons (at 20-50 MeV) being generated in ITER, and then being lost to the walls are simply catastrophic. They will not be deposited globally, but will drift out (up, down, whatever, depending on control system), and impact internal structures, unless 'ameliorated'. Basically, this represents an extraordinarily robust e-beam welding machine, capable of deep penetration into any armor tiles, to the cooling channels which are embedded less than 1 cm below the tile surface. When energy is deposited in a fraction of a second on (or in) a tile, the presence of underlying water cooling does no good for the purposes of heat removal.

  17. Peptidomic and proteomic analyses of the systemic immune response of Drosophila.

    PubMed

    Levy, Francine; Rabel, David; Charlet, Maurice; Bulet, Philippe; Hoffmann, Jules A; Ehret-Sabatier, Laurence

    2004-01-01

    Insects have developed an efficient host defense against microorganisms, which involves humoral and cellular mechanisms. Numerous data highlight similarities between defense responses of insects and innate immunity of mammals. The fruit fly, Drosophila melanogaster, is a favorable model system for the analysis of the first line defense against microorganisms. Taking advantages of improvements in mass spectrometry (MS), two-dimensional (2D) gel electrophoresis and bioinformatics, differential analyses of blood content (hemolymph) from immune-challenged versus control Drosophila were performed. Two strategies were developed: (i) peptidomic analyses through matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS and high performance liquid chromatography for molecules below 15 kDa, and (ii) proteomic studies based on 2D gel electrophoresis, MALDI-TOF fingerprinting and database searches, for compounds of greater molecular masses. The peptidomic strategy led to the detection of a large number of peptides induced in the hemolymph of challenged flies as compared to controls. Of these, 28 were characterized, amongst which were antimicrobial peptides. The 2D gel electrophoresis strategy led to the detection of 70 spots differentially regulated by at least fivefold after microbial infection. This approach yielded the identity of a series of proteins that were related to the Drosophila immune response, such as proteases, protease inhibitors, prophenoloxydase-activating enzymes, serpins and a Gram-negative binding protein-like protein. This strategy also brought to light new candidates with a potential function in the immune response (odorant-binding protein, peptidylglycine alpha-hydroxylating monooxygenase and transferrin). Interestingly, several molecules resulting from the cleavage of proteins were detected after a fungal infection. Together, peptidomic and proteomic analyses represent new tools to characterize molecules involved in the innate immune reactions of Drosophila. PMID:15556270

  18. Satellite Power System (SPS) concept definition study (Exhibit D). Volume 2: Systems\\/subsystems analyses

    Microsoft Academic Search

    G. M. Hanley

    1981-01-01

    Modifications to the reference concept were studied and the best approaches defined. The impact of the high efficiency multibandgap solar array on the reference concept design is considered. System trade studies for several solid state concepts, including the sandwich concept and a separate antenna\\/solar concept, are described. Two solid state concepts were selected and a design definition is presented for

  19. System zur Analyse Naturwissenschftlicher Curricula (A Curriculum Material Analysis System for Science).

    ERIC Educational Resources Information Center

    Haussler, Peter; Pittman, June

    This volume presents a description of the Curriculum Materials Analysis System (CMAS), and discusses its use. The volume is in two parts, providing German and English versions of the same material. CMAS was designed for use in analyzing five major aspects of curriculum use: (1) content, (2) instructional methods, (3) adaptiveness, (4)…

  20. PCG reference manual: A package for the iterative solution of large sparse linear systems on parallel computers. Version 1.0

    SciTech Connect

    Joubert, W.D. [Los Alamos National Lab., NM (United States); Carey, G.F.; Kohli, H.; Lorber, A.; McLay, R.T.; Shen, Y. [Texas Univ., Austin, TX (United States); Berner, N.A. [Texas Univ., Austin, TX (United States)]|[Los Alamos National Lab., NM (United States); Kalhan, A. [Los Alamos National Lab., NM (United States)]|[Tennessee Univ., Knoxville, TN (United States)

    1995-01-01

    PCG (Preconditioned Conjugate Gradient package) is a system for solving linear equations of the form Au = b, for A a given matrix and b and u vectors. PCG, employing various gradient-type iterative methods coupled with preconditioners, is designed for general linear systems, with emphasis on sparse systems such as these arising from discretization of partial differential equations arising from physical applications. It can be used to solve linear equations efficiently on parallel computer architectures. Much of the code is reusable across architectures and the package is portable across different systems; the machines that are currently supported is listed. This manual is intended to be the general-purpose reference describing all features of the package accessible to the user; suggestions are also given regarding which methods to use for a given problem.

  1. Kinematic and Moisture Environments of Convective Systems During TRMM-LBA: Preliminary Sounding Analyses

    NASA Technical Reports Server (NTRS)

    Halverson, J. B.; Rickenbach, T.; Pierce, H.; Roy, B.; Ferreira, R. N.; Fisch, G.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Preliminary radiosonde data are analyzed from a four station observation network that operated during TRMM-LBA. These data, which are undergoing quality control, are used to construct mean vertical profiles and time-height sections of u- and v- wind components, and also filtered time series analyses of layer mean relative humidity. Trends are identified in the humidity data which appear similar at all sites, and correlate well with multi-week changes in wind regime identified by Rickenbach et al. Higher-frequency modes of variation (3-5 day) also occur in the humidity and upper tropospheric winds and are spatially coherent among the four locations. The causes of these variations are explored, including interactions among upper tropospheric synoptic features. Finally, an attempt is made to relate the general morphology of convective systems to the vertical shear structure and thermodynamic changes that accompany contrasting wind regimes.

  2. ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS

    SciTech Connect

    WILLIAMS, J.C.

    2003-11-15

    This report documents the accident analyses and nuclear safety control options for use in Revision 7 of HNF-SD-WM-SAR-062, ''K Basins Safety Analysis Report'' and Revision 4 of HNF-SD-SNF-TSR-001, ''Technical Safety Requirements - 100 KE and 100 KW Fuel Storage Basins''. These documents will define the authorization basis for Sludge Water System (SWS) operations. This report follows the guidance of DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports'', for calculating onsite and offsite consequences. The accident analysis summary is shown in Table ES-1 below. While this document describes and discusses potential control options to either mitigate or prevent the accidents discussed herein, it should be made clear that the final control selection for any accident is determined and presented in HNF-SD-WM-SAR-062.

  3. Dynamics of the 2014 Holuhraun fissure eruption analysed by video monitoring system

    NASA Astrophysics Data System (ADS)

    Witt, Tanja; Walter, Thomas R.

    2015-04-01

    Events on the volcanic system within the axial volcanic zones are linked to plate movements. The spreading and subsequent rifting of the crust take place at the plate boundary and occurs in distinct rifting episodes. These rifting episodes are characterized by earthquakes and volcanic eruptions within the central volcano or along fissures. For the subsurface structure of a volcanic system and the behavior of the magma plumbing system during major rifting episodes two contrasting models exists, (i) vertical feeding by a deep magma source or (ii) lateral feeding through a shallow magma chamber under the central volcano. The ongoing 2014 Holuhraun eruption is providing a unique opportunity to rigorously test the feeding paths of an active fissure eruption. Here we employ video images to analyse the height and velocity variation of the lava fountains at the Holuhraun eruption fissure. On the first day of the eruption we could set up in total five high resolution video cameras. With algorithms of photogrammetry and correlation analysis we interpret the behavior of the lava fountains. Results suggest a significal lateral propagation path of the dynamics of the active vents, and a lateral migration of the peaks and lows of distinct lava fountains. Although the correlation system can change episodically and sporadically, both the frequency of the lava fountains and the eruption and rest time between single fountains remain similar for adjacent lava fountains imply a controlling process in the magma feeder system itself. We interpret the results by a lateral magma and gas flow underlying and feeding the eruption fissure. Systematic recording and analysis of video data hence help to decide which magma plumbing system is more reliable. Additionally, the dataset allows us to compare the eruption behavior to seismic datasets.

  4. Pseudopotential iteration of propagator equations

    Microsoft Academic Search

    V. I. Yukalov

    1990-01-01

    Summary  A new iterative procedure for propagator equations describing systems with singular interactions is suggested. The standard\\u000a perturbation theory for such systems beginning with the Hartree or Hartree-Fock approximations looses its sense because of\\u000a the divergence of the corresponding approximate expressions for the mass operator. To define the latter a regular procedure\\u000a containing no divergences is constructed. A new notion is

  5. Statistical model based iterative reconstruction (MBIR) in clinical CT systems. Part II. Experimental assessment of spatial resolution performance

    PubMed Central

    Li, Ke; Garrett, John; Ge, Yongshuai; Chen, Guang-Hong

    2014-01-01

    Purpose: Statistical model based iterative reconstruction (MBIR) methods have been introduced to clinical CT systems and are being used in some clinical diagnostic applications. The purpose of this paper is to experimentally assess the unique spatial resolution characteristics of this nonlinear reconstruction method and identify its potential impact on the detectabilities and the associated radiation dose levels for specific imaging tasks. Methods: The thoracic section of a pediatric phantom was repeatedly scanned 50 or 100 times using a 64-slice clinical CT scanner at four different dose levels [CTDIvol =4, 8, 12, 16 (mGy)]. Both filtered backprojection (FBP) and MBIR (Veo®, GE Healthcare, Waukesha, WI) were used for image reconstruction and results were compared with one another. Eight test objects in the phantom with contrast levels ranging from 13 to 1710 HU were used to assess spatial resolution. The axial spatial resolution was quantified with the point spread function (PSF), while the z resolution was quantified with the slice sensitivity profile. Both were measured locally on the test objects and in the image domain. The dependence of spatial resolution on contrast and dose levels was studied. The study also features a systematic investigation of the potential trade-off between spatial resolution and locally defined noise and their joint impact on the overall image quality, which was quantified by the image domain-based channelized Hotelling observer (CHO) detectability index d?. Results: (1) The axial spatial resolution of MBIR depends on both radiation dose level and image contrast level, whereas it is supposedly independent of these two factors in FBP. The axial spatial resolution of MBIR always improved with an increasing radiation dose level and/or contrast level. (2) The axial spatial resolution of MBIR became equivalent to that of FBP at some transitional contrast level, above which MBIR demonstrated superior spatial resolution than FBP (and vice versa); the value of this transitional contrast highly depended on the dose level. (3) The PSFs of MBIR could be approximated as Gaussian functions with reasonably good accuracy. (4) Thez resolution of MBIR showed similar contrast and dose dependence. (5) Noise standard deviation assessed on the edges of objects demonstrated a trade-off with spatial resolution in MBIR. (5) When both spatial resolution and image noise were considered using the CHO analysis, MBIR led to significant improvement in the overall CT image quality for both high and low contrast detection tasks at both standard and low dose levels. Conclusions: Due to the intrinsic nonlinearity of the MBIR method, many well-known CT spatial resolution and noise properties have been modified. In particular, dose dependence and contrast dependence have been introduced to the spatial resolution of CT images by MBIR. The method has also introduced some novel noise-resolution trade-off not seen in traditional CT images. While the benefits of MBIR regarding the overall image quality, as demonstrated in this work, are significant, the optimal use of this method in clinical practice demands a thorough understanding of its unique physical characteristics. PMID:24989389

  6. Assessment of Tools and Data for System-Level Dynamic Analyses

    Microsoft Academic Search

    Steven J. Piet; Nick R. Soelberg

    2011-01-01

    The only fuel cycle for which dynamic analyses and assessments are not needed is the null fuel cycle - no nuclear power. For every other concept, dynamic analyses are needed and can influence relative desirability of options. Dynamic analyses show how a fuel cycle might work during transitions from today's partial fuel cycle to something more complete, impact of technology

  7. Performance Analyses of 38 kWe Turbo-Machine Unit for Space Reactor Power Systems

    NASA Astrophysics Data System (ADS)

    Gallo, Bruno M.; El-Genk, Mohamed S.

    2008-01-01

    This paper developed a design and investigated the performance of 38 kWe turbo-machine unit for space nuclear reactor power systems with Closed Brayton Cycle (CBC) energy conversion. The compressor and turbine of this unit are scaled versions of the NASA's BRU developed in the sixties and seventies. The performance results of turbo-machine unit are calculated for rotational speed up to 45 krpm, variable reactor thermal power and system pressure, and fixed turbine and compressor inlet temperatures of 1144 K and 400 K. The analyses used a detailed turbo-machine model developed at the University of New Mexico that accounts for the various energy losses in the compressor and turbine and the effect of compressibility of the He-Xe (40 mole/g) working fluid with increased flow rate. The model also accounts for the changes in the physical and transport properties of the working fluid with temperature and pressure. Results show that a unit efficiency of 24.5% is achievable at rotation speed of 45 krpm and system pressure of 0.75 MPa, assuming shaft and electrical generator efficiencies of 86.7% and 90%. The corresponding net electric power output of the unit is 38.5 kWe, the flow rate of the working fluid is 1.667 kg/s, the pressure ratio and polytropic efficiency for the compressor are 1.60 and 83.1%, and 1.51 and 88.3% for the turbine.

  8. Performance Analyses of 38 kWe Turbo-Machine Unit for Space Reactor Power Systems

    SciTech Connect

    Gallo, Bruno M.; El-Genk, Mohamed S. [Institute for Space and Nuclear Power Studies and Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM, 87131 (United States)

    2008-01-21

    This paper developed a design and investigated the performance of 38 kWe turbo-machine unit for space nuclear reactor power systems with Closed Brayton Cycle (CBC) energy conversion. The compressor and turbine of this unit are scaled versions of the NASA's BRU developed in the sixties and seventies. The performance results of turbo-machine unit are calculated for rotational speed up to 45 krpm, variable reactor thermal power and system pressure, and fixed turbine and compressor inlet temperatures of 1144 K and 400 K. The analyses used a detailed turbo-machine model developed at University of New Mexico that accounts for the various energy losses in the compressor and turbine and the effect of compressibility of the He-Xe (40 mole/g) working fluid with increased flow rate. The model also accounts for the changes in the physical and transport properties of the working fluid with temperature and pressure. Results show that a unit efficiency of 24.5% is achievable at rotation speed of 45 krpm and system pressure of 0.75 MPa, assuming shaft and electrical generator efficiencies of 86.7% and 90%. The corresponding net electric power output of the unit is 38.5 kWe, the flow rate of the working fluid is 1.667 kg/s, the pressure ratio and polytropic efficiency for the compressor are 1.60 and 83.1%, and 1.51 and 88.3% for the turbine.

  9. Single-particle and many-body analyses of a quasiperiodic integrable system after a quench

    NASA Astrophysics Data System (ADS)

    He, Kai; Santos, Lea F.; Wright, Tod M.; Rigol, Marcos

    2013-06-01

    In general, isolated integrable quantum systems have been found to relax to an apparent equilibrium state in which the expectation values of few-body observables are described by the generalized Gibbs ensemble. However, recent work has shown that relaxation to such a generalized statistical ensemble can be precluded by localization in a quasiperiodic lattice system. Here we undertake complementary single-particle and many-body analyses of noninteracting spinless fermions and hard-core bosons within the Aubry-André model to gain insight into this phenomenon. Our investigations span both the localized and delocalized regimes of the quasiperiodic system, as well as the critical point separating the two. Considering first the case of spinless fermions, we study the dynamics of the momentum distribution function and characterize the effects of real-space and momentum-space localization on the relevant single-particle wave functions and correlation functions. We show that although some observables do not relax in the delocalized and localized regimes, the observables that do relax in these regimes do so in a manner consistent with a recently proposed Gaussian equilibration scenario, whereas relaxation at the critical point has a more exotic character. We also construct various statistical ensembles from the many-body eigenstates of the fermionic and bosonic Hamiltonians and study the effect of localization on their properties.

  10. Kalman filter-augmented iterative learning control on the iteration domain

    Microsoft Academic Search

    Hyo-Sung Ahn; Kevin L. Moore; YangQuan Chen

    2006-01-01

    In this paper a novel stochastic iterative learning control (ILC) scheme is suggested to reduce the base-line error of the ILC system along the iteration axis. Assuming knowledge of the measurement noise and process noise statistics, our ILC scheme uses a Kalman filter to estimate the error of the output measurement and a fixed gain learning controller to ensure that

  11. Application of a joint and iterative MMSE-based estimation of SNR and frequency-selective channel for OFDM systems

    NASA Astrophysics Data System (ADS)

    Savaux, Vincent; Louët, Yves; Djoko-Kouam, Moďse; Skrzypczak, Alexandre

    2013-12-01

    This article presents an iterative minimum mean square error- (MMSE-) based method for the joint estimation of signal-to-noise ratio (SNR) and frequency-selective channel in an orthogonal frequency division multiplexing (OFDM) context. We estimate the SNR thanks to the MMSE criterion and the channel frequency response by means of the linear MMSE (LMMSE). As each estimation requires the other one to be performed, the proposed algorithm is iterative. In this article, a realistic case is considered; i.e., the channel covariance matrix used in LMMSE is supposed to be totally unknown at the receiver and must be estimated. We will theoretically prove that the algorithm converges for a relevantly chosen initialization value. Furthermore simulations show that the algorithm quickly converges to a solution that is close to the one in which the covariance matrix is perfectly known. Compared to existing SNR estimation methods, the algorithm improves the trade-off between the number of required pilots and the SNR estimation quality.

  12. Additional Development and Systems Analyses of Pneumatic Technology for High Speed Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Englar, Robert J.; Willie, F. Scott; Lee, Warren J.

    1999-01-01

    In the Task I portion of this NASA research grant, configuration development and experimental investigations have been conducted on a series of pneumatic high-lift and control surface devices applied to a generic High Speed Civil Transport (HSCT) model configuration to determine their potential for improved aerodynamic performance, plus stability and control of higher performance aircraft. These investigations were intended to optimize pneumatic lift and drag performance; provide adequate control and longitudinal stability; reduce separation flowfields at high angle of attack; increase takeoff/climbout lift-to-drag ratios; and reduce system complexity and weight. Experimental aerodynamic evaluations were performed on a semi-span HSCT generic model with improved fuselage fineness ratio and with interchangeable plain flaps, blown flaps, pneumatic Circulation Control Wing (CCW) high-lift configurations, plain and blown canards, a novel Circulation Control (CC) cylinder blown canard, and a clean cruise wing for reference. Conventional tail power was also investigated for longitudinal trim capability. Also evaluated was unsteady pulsed blowing of the wing high-lift system to determine if reduced pulsed mass flow rates and blowing requirements could be made to yield the same lift as that resulting from steady-state blowing. Depending on the pulsing frequency applied, reduced mass flow rates were indeed found able to provide lift augmentation at lesser blowing values than for the steady conditions. Significant improvements in the aerodynamic characteristics leading to improved performance and stability/control were identified, and the various components were compared to evaluate the pneumatic potential of each. Aerodynamic results were provided to the Georgia Tech Aerospace System Design Lab. to conduct the companion system analyses and feasibility study (Task 2) of theses concepts applied to an operational advanced HSCT aircraft. Results and conclusions from these experimental evaluations are presented herein, as are recommendations for further development and follow-on investigations. Also provided as an Appendix for reference are the basic results from the previous pneumatic HSCT investigations.

  13. Iteration, not induction

    Microsoft Academic Search

    David E. Dobbs

    2009-01-01

    The main purpose of this note is to present and justify proof via iteration as an intuitive, creative and empowering method that is often available and preferable as an alternative to proofs via either mathematical induction or the well-ordering principle. The method of iteration depends only on the fact that any strictly decreasing sequence of positive integers must terminate in

  14. Iteration, Not Induction

    ERIC Educational Resources Information Center

    Dobbs, David E.

    2009-01-01

    The main purpose of this note is to present and justify proof via iteration as an intuitive, creative and empowering method that is often available and preferable as an alternative to proofs via either mathematical induction or the well-ordering principle. The method of iteration depends only on the fact that any strictly decreasing sequence of…

  15. Iterated Local Search

    Microsoft Academic Search

    Helena R. Lourenço; Olivier C. Martin; Thomas Stützle

    2000-01-01

    Iterated Local Search has many of the desirable features of a metaheuristic: it is simple, easy to implement, robust, and highly effective. The essential idea of Iterated Local Search lies in focusing the search not on the full space of solutions but on a smaller subspace defined by the solutions that are locally optimal for a given optimization engine. The

  16. Iterative image restoration algorithms

    Microsoft Academic Search

    Aggelos K. Katsaggelos

    This tutorial paper discusses the use of successive-approximation- based iterative restoration algorithms for the removal of linear blurs and noise from images. Iterative algorithms are particularly attractive for this application because they allow for the incorporation of prior knowledge about the class of feasible solutions, because they can be used to remove nonstationary blurs, and because they are fairly robust

  17. ITER confinement capability

    SciTech Connect

    Uckan, N.A.; Hogan, J.T.

    1990-01-01

    The confinement capability of ITER was examined for a number of operational scenarios. The reference ITER physics baseline scenario (I = 22 MA) allows ignited burn under H-mode conditions ({tau}{sub E}(H-mode) {approximately} 2 {times} {tau}{sub E}(L-mode)). At higher currents (I = 25--28 MA) at which ITER can operate for limited pulse duration, there is an increased ignition margin if low-q operation proves acceptable. About a factor of 2 reduction in helium ash concentration (from the baseline value of 10% to 5%) in the reference ITER scenario has about the same impact on ignition capability as increasing the plasma current by about 15% (from the baseline value of 22 MA to {ge}25 MA). It might be possible to further optimize the ignition capability of ITER if some of the limits on operational boundaries can be relaxed by tailoring plasma profiles. 9 refs., 4 figs.

  18. Results of the implementation on a mock-up of the full 3dB hybrid matching option of the ITER ICRH system

    SciTech Connect

    Grine, D.; Vervier, M.; Messiaen, A.; Dumortier, P. [LPP-ERM/KMS, EURATOM-Belgian State Association, TEC, Brussels (Belgium)

    2011-12-23

    Each of the two ICRH antennas for ITER must couple 20MW to the plasma in the 40-55MHz band via an array of 24 radiating shorted straps fed by four generators. The matching system must provide automatic matching control on the mean load provided by the plasma and be resilient (parallel {Gamma}{sub G} parallel <0.2) to a wide range of fast antenna load excursions occurring in ELMy plasmas. Furthermore, good control of the current distribution in the strap array must be possible for the various heating and current drive scenarios. Two load resilient matching options have been considered for ITER: the 4 'Conjugate-T'(CT) and the 4 hybrids ones, the first being presently considered as a back-up option. Automatic control of these 2 options has been developed, and tested for optimization on a low-powered scaled mock-up. Successful implementation of the simultaneous feedback control of 11 actuators for the matching of the 4 CT and for the control of the toroidal phasing has already been achieved. The matching and the array current control of the 3dB hybrid option are provided by simultaneous feedback control of the decouplers and double stub tuners (in total 23 actuators) and this has also been successfully achieved for the full array. The paper discusses the circuit implementation and presents the obtained results.

  19. Genomic and Systems Biology Analyses of Social Behavior or Evolutionary Genomic Analyses of Insect Society: Eat, Drink, and Be Scary (2011 JGI User Meeting)

    ScienceCinema

    Robinson, Gene

    2011-06-03

    The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Gene Robinson of the University of Illinois on "Genomic and Systems Biology Analyses of Social Behavior" at the 6th Annual Genomics of Energy & Environment Meeting on March 23, 2011

  20. ITER Engineering Design Activities ITER Technical Characteristics

    E-print Network

    /current drive power 73 MW (100 MW) ITER- Toroidal Field Model Coil Project Toroidal Field Coil Target Cost ~$4B (US 1/00) Construction Timescale ~8 years Current Status & Plans: Ą Finalise design by end on Construction Agreement and Site Selection (12/02) Ą Construction begins in 2003. Divertor Remote Handling

  1. Physical properties of a resin system for filling the inter-space in the ITER TF coil casing

    NASA Astrophysics Data System (ADS)

    Evans, D.; Baynahm, E.; Canfer, S.; Foussat, A.

    2014-01-01

    Each of the eighteen ITER Toroidal Field (TF) coils will consist of seven double pancakes. Each double pancake will have been individually vacuum impregnated and then the seven units assembled together, over-wrapped with glass fabric based insulation and finally vacuum impregnated again to form the TF coil winding pack [1]. The winding pack (WP) will be finally assembled into the coil casing (CC) and to allow for manufacturing tolerances and final geometric definition, a nominal 10 mm gap will exist between the winding pack and the coil case but in practice, this gap may vary between 3 and 15 mm. After assembly, the final step will be to fill the gap with a material that will maintain the final position of the WP and to uniformly transfer load from WP to CC. This paper deals with the selection of materials and techniques to fill the gap and details some of the properties of the chosen material.

  2. An Open Source Protein Gel Documentation System for Proteome Analyses Daniel Faller,*, Thomas Reinheckel, Daniel Wenzler, Sascha Hagemann, Ke Xiao,

    E-print Network

    Timmer, Jens

    in pharmaceutical chemistry and medical chemistry. The presented open source documentation and analysis systemAn Open Source Protein Gel Documentation System for Proteome Analyses Daniel Faller,*, Thomas- phoresis (2DE), spot detection and comparison by charge- coupled device (CCD) cameras or scanners and

  3. Wind Power Forecasting Error Frequency Analyses for Operational Power System Studies: Preprint

    SciTech Connect

    Florita, A.; Hodge, B. M.; Milligan, M.

    2012-08-01

    The examination of wind power forecasting errors is crucial for optimal unit commitment and economic dispatch of power systems with significant wind power penetrations. This scheduling process includes both renewable and nonrenewable generators, and the incorporation of wind power forecasts will become increasingly important as wind fleets constitute a larger portion of generation portfolios. This research considers the Western Wind and Solar Integration Study database of wind power forecasts and numerical actualizations. This database comprises more than 30,000 locations spread over the western United States, with a total wind power capacity of 960 GW. Error analyses for individual sites and for specific balancing areas are performed using the database, quantifying the fit to theoretical distributions through goodness-of-fit metrics. Insights into wind-power forecasting error distributions are established for various levels of temporal and spatial resolution, contrasts made among the frequency distribution alternatives, and recommendations put forth for harnessing the results. Empirical data are used to produce more realistic site-level forecasts than previously employed, such that higher resolution operational studies are possible. This research feeds into a larger work of renewable integration through the links wind power forecasting has with various operational issues, such as stochastic unit commitment and flexible reserve level determination.

  4. Linear ideal MHD stability calculations for ITER

    SciTech Connect

    Hogan, J.T.

    1988-01-01

    A survey of MHD stability limits has been made to address issues arising from the MHD--poloidal field design task of the US ITER project. This is a summary report on the results obtained to date. The study evaluates the dependence of ballooning, Mercier and low-n ideal linear MHD stability on key system parameters to estimate overall MHD constraints for ITER. 17 refs., 27 figs.

  5. DQS advisor: a visual interface and knowledge-based system to balance dose, quality, and reconstruction speed in iterative CT reconstruction with application to NLM-regularization

    NASA Astrophysics Data System (ADS)

    Zheng, Z.; Papenhausen, E.; Mueller, K.

    2013-11-01

    Motivated by growing concerns with regards to the x-ray dose delivered to the patient, low-dose computed tomography (CT) has gained substantial interest in recent years. However, achieving high-quality CT reconstructions from the limited projection data collected at reduced x-ray radiation is challenging, and iterative algorithms have been shown to perform much better than conventional analytical schemes in these cases. A problem with iterative methods in general is that they require users to set many parameters, and if set incorrectly high reconstruction time and/or low image quality are likely consequences. Since the interactions among parameters can be complex and thus effective settings can be difficult to identify for a given scanning scenario, these choices are often left to a highly-experienced human expert. To help alleviate this problem, we devise a computer-based assistant for this purpose, called dose, quality and speed (DQS)-advisor. It allows users to balance the three most important CT metrics--DQS--by ways of an intuitive visual interface. Using a known gold-standard, the system uses the ant-colony optimization algorithm to generate the most effective parameter settings for a comprehensive set of DQS configurations. A visual interface then presents the numerical outcome of this optimization, while a matrix display allows users to compare the corresponding images. The interface allows users to intuitively trade-off GPU-enabled reconstruction speed with quality and dose, while the system picks the associated parameter settings automatically. Further, once the knowledge has been generated, it can be used to correctly set the parameters for any new CT scan taken at similar scenarios.

  6. Iterated Belief Revision

    E-print Network

    Stalnaker, Robert

    This is a discussion of the problem of extending the basic AGM belief revision theory to iterated belief revision: the problem of formulating rules, not only for revising a basic belief state in response to potential new ...

  7. System and Cost Analyses of Broad-Band Fiber Loop Architectures

    Microsoft Academic Search

    Kevin W. Lu; Martin I. Eiger; Howard L. Lemberg

    1990-01-01

    Analyses of four broadband fiber-optic subscriber loop architectures, including active (high-speed time division multiplexing (TDM)-based) and passive (dense wavelength division multiplexing (WDM)-based, WDM-based with an analog subcarrier-multiplexing overlay, and splitter-based) double-star topologies, are presented. The analyses focus on specific demonstrated architectures and use component cost projections based on learning curves to estimate future network costs on a per-subscriber basis. Also

  8. ITER convertible blanket evaluation

    SciTech Connect

    Wong, C.P.C.; Cheng, E.

    1995-09-01

    Proposed International Thermonuclear Experimental Reactor (ITER) convertible blankets were reviewed. Key design difficulties were identified. A new particle filter concept is introduced and key performance parameters estimated. Results show that this particle filter concept can satisfy all of the convertible blanket design requirements except the generic issue of Be blanket lifetime. If the convertible blanket is an acceptable approach for ITER operation, this particle filter option should be a strong candidate.

  9. Physics research needs for ITER

    SciTech Connect

    Sauthoff, N.R.

    1995-07-01

    Design of ITER entails the application of physics design tools that have been validated against the world-wide data base of fusion research. In many cases, these tools do not yet exist and must be developed as part of the ITER physics program. ITER`s considerable increases in power and size demand significant extrapolations from the current data base; in several cases, new physical effects are projected to dominate the behavior of the ITER plasma. This paper focuses on those design tools and data that have been identified by the ITER team and are not yet available; these needs serve as the basis for the ITER Physics Research Needs, which have been developed jointly by the ITER Physics Expert Groups and the ITER design team. Development of the tools and the supporting data base is an on-going activity that constitutes a significant opportunity for contributions to the ITER program by fusion research programs world-wide.

  10. Conceptual design description for the tritium recovery system for the US ITER (International Thermonuclear Experimental Reactor) Li sub 2 O/Be water cooled blanket

    SciTech Connect

    Finn, P.A.; Sze, D.K. (Argonne National Lab., IL (USA). Fusion Power Program); Clemmer, R.G. (Pacific Northwest Lab., Richland, WA (USA))

    1990-11-01

    The tritium recovery system for the US ITER Li{sub 2}O/Be water cooled blanket processes two separate helium purge streams to recover tritium from the Li{sub 2}O zones and the Be zones of the blanket, to process the waste products, and to recirculate the helium back to the blanket. The components are selected to minimize the tritium inventory of the recovery system, and to minimize waste products. The system is robust to either an increase in the tritium release rate or to an in-leak of water in the purge system. Three major components were used to process these streams, first, 5A molecular sieves at {minus}196{degree}C separate hydrogen from the helium, second, a solid oxide electrolysis unit is used to reduce all molecular water, and third, a palladium/silver diffuser is used to ensure that only hydrogen (H{sub 2}, HT) species reach the cryogenic distillation unit. Other units are present to recover tritium from waste products but the three major components are the basis of the blanket tritium recovery system. 32 refs.

  11. Analyses of the MSLB benchmark V1000CT-2 by the coupled system code ATHLET-BIPR8KN

    SciTech Connect

    Nikonov, S. P. [RRC KI, 123182 Moscow (Russian Federation); Langenbuch, S. [GRS mbH, 85748 Garching (Germany); Lizorkin, M. P. [RRC KI, 123182 Moscow (Russian Federation); Velkov, K. [GRS mbH, 85748 Garching (Germany)

    2006-07-01

    Within the activities of OECD/NEA is being initiated the second phase of the VVER-1000 Coolant Transient Benchmark (V1000CT-2). It considers the best estimate analyses of a Main Steam Line Break (MSLB) of a VVER-1000 NPP with two exercises. The analyses have been performed with the coupled system code ATHLET-BIPR8KN which enables to perform realistic simulation of three-dimensional neutron kinetics and thermal-hydraulic processes in VVER NPP. Results are presented and analysed for the two proposed scenarios. These results are supplemented by sensitivity studies varying the number of the thermo-hydraulic channels (THC) in the core and by comparisons with point kinetics calculations. This work is of considerable importance for the validation of the coupled system code ATHLET-BIPR8KN in case of asymmetric core inlet conditions. (authors)

  12. ExtendingTheApplicationOfFormalMethodsTo Analyse Human ErrorAnd SystemFailureDuringAccidentInvestigations

    E-print Network

    Johnson, Chris

    ,Lamport'sTemporalLogicofActionsisusedtobuilda unifled accountofthehuman errorsand systemfailuresthatcontributedtotheThreeMileIsland accidentExtendingTheApplicationOfFormalMethodsTo Analyse Human ErrorAnd SystemFailureDuringAccidentInvestigations C.W. JohnsonandA.J.Telford, Glasgow AccidentAnalysisGroup, DepartmentofComputingScience, University

  13. Analyses of the Effects of Global Change on Human Health and Welfare and Human Systems (SAP 4.6)

    EPA Science Inventory

    EPA has announced the final report entitled, Synthesis and Assessment Product 4.6: Analyses of the Effects of Global Change on Human Health and Welfare and Human Systems . This Synthesis and Assessment Product 4.6 (SAP 4.6) focuses on impacts of global climate change, es...

  14. Conceptual design description for the tritium recovery system for the US ITER Li sub 2 O/Be water cooled blanket

    SciTech Connect

    Finn, P.A.; Sze, D.K. (Argonne National Lab., IL (USA)); Clemmer, R.G. (Battelle Pacific Northwest Lab., Richland, WA (USA))

    1990-09-01

    The tritium recovery system for the US ITER Li{sub 2}O/Be water cooled blanket processes two separate helium purge streams to recovery tritium from the Li{sub 2}O zones and the Be zones of the blanket, to process the waste products, and to recirculate the helium back to the blanket. The components are selected to minimize the tritium inventory of the recovery system, and to minimize waste products. The system is robust to either an increase in the tritium release rate or to an in-leak of water in the purge system. Three major components were used to process these streams, first, 5A molecular sieves at {minus}196{degree}C separate hydrogen from the helium, second, a solid oxide electrolysis unit is used to reduce all molecular water, and third, a palladium/silver diffuser is used to ensure that only hydrogen (H{sub 2}, HT) species reach the cryogenic distillation unit. The total tritium process inventory is 20g. The total capital cost is {approximately}$14M. Technical advantages of a solid oxide electrolysis unit and a palladium/silver diffuser are presented. 5 refs., 1 fig., 3 tabs.

  15. ITER instrumentation and control—Status and plans

    Microsoft Academic Search

    Anders Wallander; Lana Abadie; Haresh Dave; Franck Di Maio; Hitesh Kumar Gulati; Chandresh Hansalia; Didier Joonekindt; Jean-Yves Journeaux; Wolf-Dieter Klotz; Kirti Mahajan; Petri Makijarvi; Luigi Scibile; Denis Stepanov; Nadine Utzel; Izuru Yonekawa

    2010-01-01

    The ITER instrumentation and control (I&C) system is the term encompassing all hardware and software required to operate ITER. It has two levels of hierarchy: the central I&C systems and the plant systems I&C. The central I&C systems comprise CODAC (Control, Data Access and Communication), the central interlock system (CIS) and the central safety systems (CSS). The central I&C systems

  16. Magnet design technical report---ITER definition phase

    SciTech Connect

    Henning, C. (ed.)

    1989-04-28

    This report contains papers on the following topics: conceptual design; radiation damage of ITER magnet systems; insulation system of the magnets; critical current density and strain sensitivity; toroidal field coil structural analysis; stress analysis for the ITER central solenoid; and volt-second capabilities and PF magnet configurations.

  17. Design/cost tradeoff studies. Appendix A. Supporting analyses and tradeoffs, book 2. Earth Observatory Satellite system definition study (EOS)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Attitude reference systems for use with the Earth Observatory Satellite (EOS) are described. The systems considered are fixed and gimbaled star trackers, star mappers, and digital sun sensors. Covariance analyses were performed to determine performance for the most promising candidate in low altitude and synchronous orbits. The performance of attitude estimators that employ gyroscopes which are periodically updated by a star sensor is established by a single axis covariance analysis. The other systems considered are: (1) the propulsion system design, (2) electric power and electrical integration, (3) thermal control, (4) ground data processing, and (5) the test plan and cost reduction aspects of observatory integration and test.

  18. Strategic Petroleum Reserve (SPR) long-term monitoring system pressure data analyses

    Microsoft Academic Search

    Biringer

    1987-01-01

    This report describes analyses of high-resolution pressure data collected on Caverns 2 and 110 at the Bryan Mound, Texas, Strategic Petroleum Reserve (SPR) site. A model of cavern pressurization is developed and applied to the two caverns. Use of the model to detect cavern pressure anomalies is demonstrated. Recommendatons are provided for improvements in pressure monitoring and cavern operation to

  19. LOPA - A Method to Analyse Safety Integrity Systems according to IEC 61511

    Microsoft Academic Search

    Wilhelmshöher Allee; Paul Hildebrandt

    2007-01-01

    The Layer Of Protection Analysis, abbrev. LOPA, is a semi quantitative risk analysis method. The different layers, which are already applied or still in the planning phase will be analysed and evaluated via the LOPA in order to reduce the hazards for people, environment or machine to a tolerable residual risk. Herewith, one will consider any imaginable damage initiating events.

  20. Plasma vertical stabilisation in ITER

    NASA Astrophysics Data System (ADS)

    Gribov, Y.; Kavin, A.; Lukash, V.; Khayrutdinov, R.; Huijsmans, G. T. A.; Loarte, A.; Snipes, J. A.; Zabeo, L.

    2015-07-01

    This paper describes the progress in analysis of the ITER plasma vertical stabilisation (VS) system since its design review in 2007–2008. Two indices characterising plasma VS were studied. These are (1) the maximum value of plasma vertical displacement due to free drift that can be stopped by the VS system and (2) the maximum root mean square value of low frequency noise in the dZ/dt measurement signal used in the VS feedback loop. The first VS index was calculated using the PET code for 15 MA plasmas with the nominal position and shape. The second VS index was studied with the DINA code in the most demanding simulations for plasma magnetic control of 15 MA scenarios with the fastest plasma current ramp-up and early X-point formation, the fastest plasma current ramp-down in a divertor configuration, and an H to L mode transition at the current flattop. The studies performed demonstrate that the VS in-vessel coils, adopted recently in the baseline design, significantly increase the range of plasma controllability in comparison with the stabilising systems VS1 and VS2, providing operating margins sufficient to achieve ITER's goals specified in the project requirements. Additionally two sets of the DINA code simulations were performed with the goal of assessment of the capability of the PF system with the VS in-vessel coils: (i) to control the position of runaway electrons generated during disruptions in 15 MA scenarios and (ii) to trigger ELMs in H-mode plasmas of 7.5 MA/2.65 T scenarios planned for the early phase of ITER operation. It was also shown that ferromagnetic structures of the vacuum vessel (ferromagnetic inserts) and test blanket modules insignificantly affect the plasma VS.

  1. Overview on Experiments On ITER-like Antenna On JET And ICRF Antenna Design For ITER

    NASA Astrophysics Data System (ADS)

    Nightingale, M. P. S.; Durodié, F.; Argouarch, A.; Beaumont, B.; Becoulet, A.; Bernard, J.-M.; Blackman, T.; Caughman, J.; Dumortier, P.; Edwards, D.; Fanthome, J.; Gassman, T.; Goulding, R.; Graham, M.; Hamlyn-Harris, C.; Hancock, D.; Huygen, S.; Jacquet, P.; Kazarian, F.; Koch, R.; Lamalle, P. U.; Lerche, E.; Louche, F.; Maggiora, R.; Mayoral, M.-L.; Messiaen, A. M.; Milanesio, D.; Monakhov, I.; Mukherjee, A.; Nicholls, K.; Noterdaeme, J.-M.; Ongena, J.; Rasmussen, D.; Rimini, F.; Sartori, R.; Stork, D.; Van Eester, D.; Vervier, M.; Vrancken, M.; Vulliez, K.; Whitehurst, A.; Wilson, D.; Wooldridge, E.

    2009-11-01

    Following an overview of the ITER Ion Cyclotron Resonance Frequency (ICRF) system, the JET ITER-like antenna (ILA) will be described. The ILA was designed to test the following ITER issues: (a) reliable operation at power densities of order 8 MW/m2 at voltages up to 45 kV using a close-packed array of straps; (b) powering through ELMs using an internal (in-vacuum) conjugate-T junction; (c) protection from arcing in a conjugate-T configuration, using both existing and novel systems; and (d) resilience to disruption forces. ITER-relevant results have been achieved: operation at high coupled power density; control of the antenna matching elements in the presence of high inter-strap coupling, use of four conjugate-T systems (as would be used in ITER, should a conjugate-T approach be used); operation with RF voltages on the antenna structures up to 42 kV; achievement of ELM tolerance with a conjugate-T configuration by operating at 3? real impedance at the conjugate-T point; and validation of arc detection systems on conjugate-T configurations in ELMy H-mode plasmas. The impact of these results on the predicted performance and design of the ITER antenna will be reviewed. In particular, the implications of the RF coupling measured on JET will be discussed.

  2. Overview on Experiments On ITER-like Antenna On JET And ICRF Antenna Design For ITER

    SciTech Connect

    Nightingale, M. P. S.; Blackman, T.; Edwards, D.; Fanthome, J.; Graham, M.; Hamlyn-Harris, C.; Hancock, D.; Jacquet, P.; Mayoral, M.-L.; Monakhov, I.; Nicholls, K.; Stork, D.; Whitehurst, A.; Wilson, D.; Wooldridge, E. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Durodie, F.; Dumortier, P.; Huygen, S.; Koch, R.; Lerche, E. [Laboratory for Plasma Physics, Ecole Royale Militaire/Koninklijke Militaire School, Association Euratom-Belgian State, Avenue de la Renaissance 30, B-1000 Brussels (Belgium)] (and others)

    2009-11-26

    Following an overview of the ITER Ion Cyclotron Resonance Frequency (ICRF) system, the JET ITER-like antenna (ILA) will be described. The ILA was designed to test the following ITER issues: (a) reliable operation at power densities of order 8 MW/m{sup 2} at voltages up to 45 kV using a close-packed array of straps; (b) powering through ELMs using an internal (in-vacuum) conjugate-T junction; (c) protection from arcing in a conjugate-T configuration, using both existing and novel systems; and (d) resilience to disruption forces. ITER-relevant results have been achieved: operation at high coupled power density; control of the antenna matching elements in the presence of high inter-strap coupling, use of four conjugate-T systems (as would be used in ITER, should a conjugate-T approach be used); operation with RF voltages on the antenna structures up to 42 kV; achievement of ELM tolerance with a conjugate-T configuration by operating at 3{omega} real impedance at the conjugate-T point; and validation of arc detection systems on conjugate-T configurations in ELMy H-mode plasmas. The impact of these results on the predicted performance and design of the ITER antenna will be reviewed. In particular, the implications of the RF coupling measured on JET will be discussed.

  3. Iterative Optimal and Adaptive Control of a Near Isothermal Liquid Piston Air Compressor in a Compressed Air Energy Storage System

    E-print Network

    Li, Perry Y.

    in a Compressed Air Energy Storage System Farzad A. Shirazi, Mohsen Saadat, Bo Yan, Perry Y. Li, and Terry W/expanders are crucial for the economical viability of a Compressed Air Energy Storage (CAES) system such as the one in the Com- pressed Air Energy Storage (CAES) system for offshore wind turbine that has recently been

  4. Averaging and Metropolis iterations for positron emission tomography.

    PubMed

    Szirmay-Kalos, László; Magdics, Milán; Tóth, Balázs; Bükki, Tamás

    2013-03-01

    Iterative positron emission tomography (PET) reconstruction computes projections between the voxel space and the lines of response (LOR) space, which are mathematically equivalent to the evaluation of multi-dimensional integrals. The dimension of the integration domain can be very high if scattering needs to be compensated. Monte Carlo (MC) quadrature is a straightforward method to approximate high-dimensional integrals. As the numbers of voxels and LORs can be in the order of hundred millions and the projection also depends on the measured object, the quadratures cannot be precomputed, but Monte Carlo simulation should take place on-the-fly during the iterative reconstruction process. This paper presents modifications of the maximum likelihood, expectation maximization (ML-EM) iteration scheme to reduce the reconstruction error due to the on-the-fly MC approximations of forward and back projections. If the MC sample locations are the same in every iteration step of the ML-EM scheme, then the approximation error will lead to a modified reconstruction result. However, when random estimates are statistically independent in different iteration steps, then the iteration may either diverge or fluctuate around the solution. Our goal is to increase the accuracy and the stability of the iterative solution while keeping the number of random samples and therefore the reconstruction time low. We first analyze the error behavior of ML-EM iteration with on-the-fly MC projections, then propose two solutions: averaging iteration and Metropolis iteration. Averaging iteration averages forward projection estimates during the iteration sequence. Metropolis iteration rejects those forward projection estimates that would compromise the reconstruction and also guarantees the unbiasedness of the tracer density estimate. We demonstrate that these techniques allow a significant reduction of the required number of samples and thus the reconstruction time. The proposed methods are built into the Teratomo system. PMID:23221817

  5. Parent Stars of Extrasolar Planets. VI. Abundance Analyses of 20 New Systems

    Microsoft Academic Search

    Guillermo Gonzalez; Chris Laws; Sudhi Tyagi; B. E. Reddy

    2001-01-01

    The results of new spectroscopic analyses of 20 recently reported extrasolar planet parent stars are presented. The companion of one of these stars, HD 10697, has recently been shown to have a mass in the brown dwarf regime; we find [Fe\\/H]=+0.16 for it. For the remaining sample, we derive [Fe\\/H] estimates ranging from -0.41 to +0.37, with an average value

  6. Spectroscopic analyses of the parent stars of extrasolar planetary system candidates

    Microsoft Academic Search

    Guillermo Gonzalez

    1998-01-01

    The stars rho () 1 Cnc, rho CrB, 16 Cyg B, 51 Peg, 47 UMa, 70 Vir, and HD 114762 have recently been proposed to harbor planetary mass companions based on small amplitude radial velocity variations. From spectroscopic analyses we derive the following values of [Fe\\/H] for these stars: 0.29, -0.29, 0.06, 0.21, 0.01, -0.03, and -0.60 (all with an

  7. Diagnostics for ITER; A status report (invited)

    Microsoft Academic Search

    K. M. Young

    1992-01-01

    The protocol agreement allowing the design of the International Thermonuclear Engineering Reactor (ITER) to proceed will be signed early this year. There is already a small U.S. Program evaluating diagnostic capability for this device and there will shortly be an international effort on diagnostics to ensure satisfactory integration of the diagnostic systems with all the complex systems that will be

  8. Preconditioned iterative methods for partial differential equations

    Microsoft Academic Search

    G. K. Leaf; M. Minkoff; J. C. Diaz

    1987-01-01

    In this paper we consider several preconditioners and iterative methods for solving the linear algebraic system associated with a partial differential equation. Our interest stems from earlier work in Method of Lines (MOL) software for solving kinetics-diffusion equations and a recognition that the solution of the underlying linear system at each timestep is crucial in terms of computational storage and

  9. The precision and accuracy of iterative and non-iterative methods of photopeak integration in activation analysis, with particular reference to the analysis of multiplets

    USGS Publications Warehouse

    Baedecker, P.A.

    1977-01-01

    The relative precisions obtainable using two digital methods, and three iterative least squares fitting procedures of photopeak integration have been compared empirically using 12 replicate counts of a test sample with 14 photopeaks of varying intensity. The accuracy by which the various iterative fitting methods could analyse synthetic doublets has also been evaluated, and compared with a simple non-iterative approach. ?? 1977 Akade??miai Kiado??.

  10. Analyses of Variable Refrigerant Flow and Exergy in Air Conditioning Systems

    Microsoft Academic Search

    Rashid Ali Alshatti

    2011-01-01

    This thesis consists of two research problems in the air conditioning (A\\/C) area. For the first problem, the aim is to model and simulate a variable refrigerant flow (VRF) air conditioning system. The coefficient of performance (COP) for refrigeration or heat pump system is one of the critical parameters for designing an air conditioning system. The modeling of the system

  11. Characterizing unmanned system autonomy: contextual autonomous capability and level of autonomy analyses

    Microsoft Academic Search

    Hui-Min Huang; Kerry Pavek; Mark Ragon; Jeffry Jones; Elena Messina; James Albus

    2007-01-01

    The Autonomy Levels for Unmanned Systems (ALFUS) workshop series was convened to address the autonomous nature of unmanned, robotic systems, or unmanned systems (UMS). Practitioners have different perceptions or different expectations for these systems. The requirements on human interactions, the types of tasks, the teaming of the UMSs and the humans, and the operating environment are just a few of

  12. Aircraft Rollout Iterative Energy Simulation

    NASA Technical Reports Server (NTRS)

    Kinoshita, L.

    1986-01-01

    Aircraft Rollout Iterative Energy Simulation (ARIES) program analyzes aircraft-brake performance during rollout. Simulates threedegree-of-freedom rollout after nose-gear touchdown. Amount of brake energy dissipated during aircraft landing determines life expectancy of brake pads. ARIES incorporates brake pressure, actual flight data, crosswinds, and runway characteristics to calculate following: brake energy during rollout for up to four independent brake systems; time profiles of rollout distance, velocity, deceleration, and lateral runway position; and all aerodynamic moments on aircraft. ARIES written in FORTRAN 77 for batch execution.

  13. Iterates of maps with symmetry

    NASA Technical Reports Server (NTRS)

    Chossat, Pascal; Golubitsky, Martin

    1988-01-01

    Fixed-point bifurcation, period doubling, and Hopf bifurcation (HB) for iterates of equivariant mappings are investigated analytically, with a focus on HB in the presence of symmetry. An algebraic formulation for the hypotheses of the theorem of Ruelle (1973) is derived, and the case of standing waves in a system of ordinary differential equations with O(2) symmetry is considered in detail. In this case, it is shown that HB can lead directly to motion on an invariant 3-torus, with an unexpected third frequency due to drift of standing waves along the torus.

  14. a Generalized Iterative Scheme Method for Determining Pulse Sequences and Pulse Sequence Design in NMR Through Fixed Point Theory Analysis

    Microsoft Academic Search

    Cathy Meryl Lerner

    1990-01-01

    A method is derived for determining initial pulse sequences for iterative scheme techniques to yield desired responses of a spin system for broadband and narrowband behaviour, through an extension and generalization of the iterative scheme method of Tycko, Pines, and Guckenheimer. In the iterative scheme method of Tycko et al., an iterative scheme is derived that is applied repetitively to

  15. Translating relational queries into iterative programs

    SciTech Connect

    Freytag, J.C.

    1987-01-01

    This book investigates the problem of translating relational queries into iterative programs using methods and techniques from the areas of functional programming and program transformation. The first part presents two algorithms which generate iterative programs from algebra-based query specifications. While the first algorithm is based on the transformation of recursive programs, the second uses functional expressions to generate the final iterative form. In the second part the same techniques generate efficient programs for the evaluation of aggregate functions in relational database systems. In several steps, programs which perform aggregation after sorting, are transformed into programs which perform aggregation while sorting. The third part then investigates the Lisp-dialect T as a possible implementation language for database systems.

  16. IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 58, NO. 10, OCTOBER 2010 2861 Iterative Soft Compensation for OFDM Systems

    E-print Network

    Ping, Li

    in orthogonal frequency-division multiplexing (OFDM) systems to reduce the peak-to-average power ratio (PAPR. However, OFDM systems suffer from a high peak-to-average power ratio (PAPR) problem. This makes OFDM more prone to the non-linear effect of transmitter devices than single-carrier schemes. Various PAPR

  17. Failure analyses of 3D Sip (system-in-package) and WLP (wafer-level package) by finite element methods

    Microsoft Academic Search

    John Lau; Xiaowu Zheng; Cheryl Selvanayagam

    2009-01-01

    In this study, three examples of failure analyses of electronic packaging by using the finite element method are presented. These are: (1) the failures (delaminations) near the interface between the filled copper and the silicon and between the copper and the silicon dioxide dielectric of the TSV of a 3D system-in-package (SiP) due to the local thermal expansion mismatch between

  18. Computer-based analyses of the protein constituents of transport systems catalysing export of complex carbohydrates in bacteria

    Microsoft Academic Search

    Ian T. Paulsen; Alison M. Beness; Milton H. Saier

    1997-01-01

    Bacteria synthesize and secrete an array of complex carbohydrates including exopolysaccharides (EPSs), capsular polysaccharides (CPSs), lipopolysaccharides (LPSs), lipo-oligosaccharides (LOSs) and teichoic acids (TCAs). We have analysed the families of homologous proteins that appear to mediate excretion of complex carbohydrates into or across the bacterial cell envelope. Two principal families of cytoplasmic-membrane transport systems appear to drive polysaccharide export: polysaccharide-specif ic

  19. Analysing the capabilities and limitations of tracer tests in stream-aquifer systems

    USGS Publications Warehouse

    Wagner, B.J.; Harvey, J.W.

    2001-01-01

    The goal of this study was to identify the limitations that apply when we couple conservative-tracer injection with reactive solute sampling to identify the transport and reaction processes active in a stream. Our methodology applies Monte Carlo uncertainty analysis to assess the ability of the tracer approach to identify the governing transport and reaction processes for a wide range of stream-solute transport and reaction scenarios likely to be encountered in high-gradient streams. Our analyses identified dimensionless factors that define the capabilities and limitations of the tracer approach. These factors provide a framework for comparing and contrasting alternative tracer test designs.

  20. Instrumentation and control standardization in the ITER project

    Microsoft Academic Search

    J. Y. Journeaux; D. Joonekindt; W. D. Klotz; P. Mäkijärvi; A. Wallander; I. Yonekawa

    2011-01-01

    The ITER instrumentation and control (I&C) system is the term encompassing all hardware and software required to operate ITER. It has two levels of hierarchy: the central I&C systems and the plant systems I&C. The plant systems I&C consists of thousands of computers processing hundreds of thousands of signals. The plant systems I&C, being the hardware interfacing layer for operating

  1. ITER Fusion Energy

    ScienceCinema

    Dr. Norbert Holtkamp

    2010-01-08

    ITER (in Latin ?the way?) is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier over one and thus release energy. In the fusion process two isotopes of hydrogen ? deuterium and tritium ? fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q ? 10 (input power 50 MW / output power 500 MW). The ITER Organization was officially established in Cadarache, France, on 24 October 2007. The seven members engaged in the project ? China, the European Union, India, Japan, Korea, Russia and the United States ? represent more than half the world?s population. The costs for ITER are shared by the seven members. The cost for the construction will be approximately 5.5 billion Euros, a similar amount is foreseen for the twenty-year phase of operation and the subsequent decommissioning.

  2. CAD Development Design Iterative

    E-print Network

    Krovi, Venkat

    Abstract CAD Development A Design Iterative Concept D B Testing Model Analysis C Building n Solid Drawing of CAD which, if you ask anyone who's only previous option was to blueprint, the response is that technology and computers have come a long way! CAD Programs What is Virtual Prototyping and its Benefits n

  3. A New Approach for Analysing National Innovation Systems in Emerging and Developing Countries

    ERIC Educational Resources Information Center

    Seidel, Uwe; Muller, Lysann; Meier zu Kocker, Gerd; Filho, Guajarino de Araujo

    2013-01-01

    This paper presents a tool for the indicator-based analysis of national innovation systems (ANIS). ANIS identifies the economic strengths and weaknesses of a country-wide, regional or local system and includes a comprehensive examination and evaluation of the status of existing innovation systems. The use of a particular form of expert interviews…

  4. Conservative availability analyses including dependent failures in redundant I&C-systems with recurrent tests

    Microsoft Academic Search

    H. D. Fischer

    2003-01-01

    In this paper analytic formulae are derived to estimate conservatively the unavailability of a two out of four digital safety Instrumentation and Control (I&C) system with recurrent tests. The analytic formulae disclose the influence of the different parameters on the system’s unavailability. In particular, the choice of a proper test interval is essential to guarantee the required low unavailability. The

  5. Sensitivity and uncertainty analyses applied to one-dimensional radionuclide transport in a layered fractured rock: MULTFRAC --Analytic solutions and local sensitivities; Phase 2, Iterative performance assessment: Volume 1

    SciTech Connect

    Gureghian, A.B.; Wu, Y.T.; Sagar, B. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses; Codell, R.A. [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-12-01

    Exact analytical solutions based on the Laplace transforms are derived for describing the one-dimensional space-time-dependent, advective transport of a decaying species in a layered, saturated rock system intersected by a planar fracture of varying aperture. These solutions, which account for advection in fracture, molecular diffusion into the rock matrix, adsorption in both fracture and matrix, and radioactive decay, predict the concentrations in both fracture and rock matrix and the cumulative mass in the fracture. The solute migration domain in both fracture and rock is assumed to be semi-infinite with non-zero initial conditions. The concentration of each nuclide at the source is allowed to decay either continuously or according to some periodical fluctuations where both are subjected to either a step or band release mode. Two numerical examples related to the transport of Np-237 and Cm-245 in a five-layered system of fractured rock were used to verify these solutions with several well established evaluation methods of Laplace inversion integrals in the real and complex domain. In addition, with respect to the model parameters, a comparison of the analytically derived local sensitivities for the concentration and cumulative mass of Np-237 in the fracture with the ones obtained through a finite-difference method of approximation is also reported.

  6. Weak-signal iterative holography.

    PubMed

    Watnik, Abbie T; Lebow, Paul S

    2015-04-01

    An iterative holographic table-top experiment is presented, where a recorded hologram is used to re-illuminate the initial target. With this beam shaping setup, more light is directed to the target for each iteration until a convergence limit is met. We experimentally examine convergence properties of this iterative hologram reconstruction approach for weak object signals and compare with theory. PMID:25967166

  7. Iterative Closest Point Introduction to

    E-print Network

    Kosecka, Jana

    1 Iterative Closest Point Algorithm Introduction to Mobile Robotics Slides adopted from: Wolfram rotation/translation in one step #12;9 ICP-Algorithm Idea: iterate to find alignment Iterated Closest (outlier) point pairs #12;12 Performance of Variants Various aspects of performance: Speed Stability

  8. Performance Evaluation of Iterative Tomography Algorithms for Incomplete Projection Data

    Microsoft Academic Search

    Debasish Mishra; Jon P. Longtin; Raman P. Singh; Vishwanath Prasad

    2004-01-01

    Projection data obtained through optical techniques for tomographic measurements, such as interferometry for refractive-index-based measurements, are often incomplete. This is due to limitations in the optical system, data storage, and alignment and vignette issues. Algebraic iterative reconstruction techniques are usually favored for such incomplete projections. A number of iterative algorithms, based on additive and multiplicative corrections, are used with a

  9. Iterative method for dynamic condensation combined with substructuring scheme

    Microsoft Academic Search

    Dongsoo Choi; Hyungi Kim; Maenghyo Cho

    2008-01-01

    An iterated improved reduced system (IIRS) procedure combined with substructuring scheme for both undamped and nonclassically damped structures is presented. Iterated IIRS method is an efficient reduction technique because the highly accurate eigenproperties from the repeatedly updated condensed matrices can be obtained without consuming expensive computational cost. However, single domain direct approach of this method to large structures requires much

  10. Fixed point theory of iterative excitation schemes in NMR

    Microsoft Academic Search

    R. Tycko; A. Pines; J. Guckenheimer

    1985-01-01

    Iterative schemes for NMR have been developed by several groups. A theoretical framework based on mathematical dynamics is described for such iterative schemes in nonlinear NMR excitation. This is applicable to any system subjected to coherent radiation or other experimentally controllable external forces. The effect of the excitation, usually a pulse sequence, can be summarized by a propagator or superpropagator

  11. Nuclear aspects of diagnostics in RTO\\/RC ITER

    Microsoft Academic Search

    C. I. Walker; S. Yamamoto; A. Costley; L. deKock; K. Ebisawa; G. Janeschitz; V. Khripunov; E. Martin; G. Vayakis

    2000-01-01

    ITER (international thermonuclear experimental reactor) will be the first fusion device where the design of the plasma diagnostic systems will make extensive use of the materials and techniques developed in the nuclear technology field. The designs have to satisfy stringent requirements for tritium confinement, nuclear shielding and vacuum integrity. This paper introduces the requirements for diagnostics in the ITER long

  12. Electromagnetic field and force analyses of a noncontacting conveyance system for steel mill application

    Microsoft Academic Search

    Cheng-Tsung Liu; Sung-Yi Yao

    2002-01-01

    Based on the design concepts of linear induction motors, an electromagnetic device has been constructed to investigate its feasibility for noncontacting steel-plate conveyance system applications. The system is intended to provide the desired lift, propulsive, and guidance forces to the steel plate simultaneously. Three-dimensional (3-D) field distributions and force characteristics have been investigated through a system state model and finite

  13. Designs and analyses of flywheel energy storage systems using high- T c superconductor bearings

    Microsoft Academic Search

    T. H Sung; S. C Han; Y. H Han; J. S Lee; N. H Jeong; S. D Hwang; S. K Choi

    2002-01-01

    A horizontal axle-type flywheel energy storage system was manufactured using high-Tc superconductor bearings. The system running in a vacuum chamber mainly consists of a composite flywheel rotor, superconductor bearings, a motor\\/generator and its controller. The present system was designed to have an energy storage capacity of 440 Wh at its operating speed of 40,000 rpm, which is way above two

  14. Challenges for Cryogenics at Iter

    NASA Astrophysics Data System (ADS)

    Serio, L.

    2010-04-01

    Nuclear fusion of light nuclei is a promising option to provide clean, safe and cost competitive energy in the future. The ITER experimental reactor being designed by seven partners representing more than half of the world population will be assembled at Cadarache, South of France in the next decade. It is a thermonuclear fusion Tokamak that requires high magnetic fields to confine and stabilize the plasma. Cryogenic technology is extensively employed to achieve low-temperature conditions for the magnet and vacuum pumping systems. Efficient and reliable continuous operation shall be achieved despite unprecedented dynamic heat loads due to magnetic field variations and neutron production from the fusion reaction. Constraints and requirements of the largest superconducting Tokamak machine have been analyzed. Safety and technical risks have been initially assessed and proposals to mitigate the consequences analyzed. Industrial standards and components are being investigated to anticipate the requirements of reliable and efficient large scale energy production. After describing the basic features of ITER and its cryogenic system, we shall present the key design requirements, improvements, optimizations and challenges.

  15. Systematic testing of an integrated systems model for coastal zone management using sensitivity and uncertainty analyses

    Microsoft Academic Search

    T. G. Nguyen; J. L. De Kok

    2007-01-01

    Systematic testing of integrated systems models is extremely important but its difficulty is widely underestimated. The inherent complexity of the integrated systems models, the philosophical debate about the model validity and validation, the uncertainty in model inputs, parameters and future context and the scarcity of field data complicate model validation. This calls for a validation framework and procedures which can

  16. Systems Performance Analyses of Alaska Wind-Diesel Projects; Kotzebue, Alaska (Fact Sheet)

    SciTech Connect

    Baring-Gould, I.

    2009-04-01

    This fact sheet summarizes a systems performance analysis of the wind-diesel project in Kotzebue, Alaska. Data provided for this project include wind turbine output, average wind speed, average net capacity factor, and optimal net capacity factor based on Alaska Energy Authority wind data, estimated fuel savings, and wind system availability.

  17. Systems Performance Analyses of Alaska Wind-Diesel Projects; Toksook Bay, Alaska (Fact Sheet)

    SciTech Connect

    Baring-Gould, I.

    2009-04-01

    This fact sheet summarizes a systems performance analysis of the wind-diesel project in Toksook Bay, Alaska. Data provided for this project include community load data, average wind turbine output, average diesel plant output, thermal load data, average net capacity factor, optimal net capacity factor based on Alaska Energy Authority wind data, average net wind penetration, estimated fuel savings, and wind system availability.

  18. Systems Performance Analyses of Alaska Wind-Diesel Projects; Kasigluk, Alaska (Fact Sheet)

    SciTech Connect

    Baring-Gould, I.

    2009-04-01

    This fact sheet summarizes a systems performance analysis of the wind-diesel project in Kasigluk, Alaska. Data provided for this project include community load data, average wind turbine output, average diesel plant output, thermal load data, average net capacity factor, average net wind penetration, estimated fuel savings, and wind system availability.

  19. A Probabilistic Model Checking Approach to Analysing Reliability, Availability, and Maintainability of a Single Satellite System

    E-print Network

    Miller, Alice

    constellations and space systems to ensure re- liable and dependable missions. These kinds of satellites have (RAM) analysis has been indispensable in the design phase of satellites in order to achieve minimum--Satellites now form a core component for space based systems such as GPS and GLONAS which provide location

  20. VOLTAGE COLLAPSE AND TRANSIENT ENERGY FUNCTION ANALYSES OF AC\\/DC SYSTEMS

    Microsoft Academic Search

    Claudio A. Canizares

    1991-01-01

    Abstract This thesis presents a thorough analysis of saddle-node bifurcations for power system dynamic models, including a third order representation of high voltage direct current (HVDC) transmission, classic ac generator dynamics with reactive flows, and volt- age and frequency dependent load models. Extensions of the Point of Collapse and Continuation methods, initially used in ac system voltage stability studies, are

  1. Energy efficiency analyses of active flow aftertreatment systems for lean burn internal combustion engines

    Microsoft Academic Search

    Ming Zheng; Graham T. Reader

    2004-01-01

    The use of three way catalytic converters in stoichiometric burn reciprocating internal combustion engine systems has proved to be an effective and efficient method for reducing the level of criteria pollutants. However, such passive systems have not been as successful in emission amelioration when combined with lean burn engines. This is because of the thermochemical nature of the exhaust gases

  2. A comparison of element-by-element preconditioned iterative methods for solid and structural mechanics

    SciTech Connect

    Ferencz, R.M.

    1988-10-01

    Past work with element-by-element (EBE) preconditioned conjugate gradient iterative solution strategies has shown these techniques can be effective for large-scale, three-dimensional calculations in solid and structural mechanics. Significant gains over the profile storage direct solution method traditionally used in implicit finite element codes have been observed for a variety of real engineering analyses, especially in solid mechanics. Structural mechanics applications have proved less successful due to the ill-conditioned linear systems engendered by standard structural discretizations. This lack of robustness has recently motivated reconsideration of Lanczos-based algorithms as alternative iterative drivers. In this paper we compare the relative strengths of the conjugate gradient and Lanczos drivers when coupled with EBE preconditioning. The performance of the two methods is characterized, and compared with direct solution, using a model problem and a number of real engineering meshes. 26 refs., 14 figs., 2 tabs.

  3. SURE: a system of computer codes for performing sensitivity/uncertainty analyses with the RELAP code. [PWR

    SciTech Connect

    Bjerke, M.A.

    1983-02-01

    A package of computer codes has been developed to perform a nonlinear uncertainty analysis on transient thermal-hydraulic systems which are modeled with the RELAP computer code. Using an uncertainty around the analyses of experiments in the PWR-BDHT Separate Effects Program at Oak Ridge National Laboratory. The use of FORTRAN programs running interactively on the PDP-10 computer has made the system very easy to use and provided great flexibility in the choice of processing paths. Several experiments simulating a loss-of-coolant accident in a nuclear reactor have been successfully analyzed. It has been shown that the system can be automated easily to further simplify its use and that the conversion of the entire system to a base code other than RELAP is possible.

  4. Optimization of currents in ITER correction coils

    NASA Astrophysics Data System (ADS)

    Amoskov, V. M.; Belyakov, V. A.; Gribov, Yu. A.; Lamzin, E. A.; Maximenkova, N. A.; Sytchevsky, S. E.

    2015-05-01

    In tokamaks non-axisymmetric magnetic field perturbations (error fields) can induce in plasma locked modes and cause disruption. In ITER the main contributor to error fields is assembly and manufacturing errors of the magnet system of the machine. To suppress intrinsic error fields and guarantee the expected plasma performance ITER is provided with the proper correction coils (CC). The paper is related to optimization of CC currents. The optimization takes into account as constraints both CC current capacities and an allowable level of error fields.

  5. Iterative system buckling analysis, considering a fictitious axial force to determine effective length factors for multi-story frames

    Microsoft Academic Search

    Dong-Ho Choi; Hoon Yoo

    2009-01-01

    Traditional elastic buckling analysis, based on the system buckling approach, is a convenient tool for the evaluation of effective length factors of columns, in the stability design of multi-story frames. This method is superior to other analytical approaches, such as the isolated subassembly and story-based approaches, in that the inter-story and inter-column interactions are inherently taken into account. Nevertheless, use

  6. Systematic redundant residue number system codes: analytical upper bound and iterative decoding performance over AWGN and Rayleigh channels

    Microsoft Academic Search

    Tong-hooi Liew; Lie-liang Yang; Lajos Hanzo

    2006-01-01

    Abstract, The novel family of redundant residue number system (RRNS) codes is studied. RRNS codes constitute max-imum-minimum distance block codes, exhibiting identical distance properties to Reed-Solomon codes. Binary to RRNS symbol-mapping methods are proposed, in order to implement both systematic and nonsystematic RRNS codes. Furthermore, the upper-bound performance of systematic RRNS codes is inves-tigated, when maximum-likelihood (ML) soft decoding is

  7. Characterizing unmanned system autonomy: contextual autonomous capability and level of autonomy analyses

    NASA Astrophysics Data System (ADS)

    Huang, Hui-Min; Pavek, Kerry; Ragon, Mark; Jones, Jeffry; Messina, Elena; Albus, James

    2007-04-01

    The Autonomy Levels for Unmanned Systems (ALFUS) workshop series was convened to address the autonomous nature of unmanned, robotic systems, or unmanned systems (UMS). Practitioners have different perceptions or different expectations for these systems. The requirements on human interactions, the types of tasks, the teaming of the UMSs and the humans, and the operating environment are just a few of the issues that need to be clarified. Also needed is a set of definitions and a model with which the autonomous capability of the UMS can be described. This paper reports the current results and status of the ALFUS framework, which practitioners can apply to analyze the autonomy requirements and to evaluate the performance of their robotic programs.

  8. Preconditioned Iterative Regularization Ill--Posed Problems

    E-print Network

    Plemmons, Robert J.

    Preconditioned Iterative Regularization for Ill--Posed Problems Martin Hanke, \\Lambda James Nagy y for solving large scale structured linear systems Hf = g + j, arising from the discretization of ill­ posed regularized for solving ill­posed problems by using the spectral decomposition of the preconditioner. Key

  9. Iterative learning control for biped walking

    Microsoft Academic Search

    Qi-Zhi Zhang; Chee-Meng Chew; Ya-Li Zhou; Qiu-Ling Zhao; Pei Li

    2010-01-01

    In this paper, an iterative learning control (ILC) approach is proposed for biped walking control. The biped robot is powered by applying an impulsive push along the stance leg just before the heel strikes. The ILC law is designed based on Poincare? map, and applied to learn the desired impulsive push at every step in the presence of system uncertainties.

  10. Applying I-FGM to image retrieval and an I-FGM system performance analyses

    NASA Astrophysics Data System (ADS)

    Santos, Eugene, Jr.; Santos, Eunice E.; Nguyen, Hien; Pan, Long; Korah, John; Zhao, Qunhua; Xia, Huadong

    2007-04-01

    Intelligent Foraging, Gathering and Matching (I-FGM) combines a unique multi-agent architecture with a novel partial processing paradigm to provide a solution for real-time information retrieval in large and dynamic databases. I-FGM provides a unified framework for combining the results from various heterogeneous databases and seeks to provide easily verifiable performance guarantees. In our previous work, I-FGM had been implemented and validated with experiments on dynamic text data. However, the heterogeneity of search spaces requires our system having the ability to effectively handle various types of data. Besides texts, images are the most significant and fundamental data for information retrieval. In this paper, we extend the I-FGM system to incorporate images in its search spaces using a region-based Wavelet Image Retrieval algorithm called WALRUS. Similar to what we did for text retrieval, we modified the WALRUS algorithm to partially and incrementally extract the regions from an image and measure the similarity value of this image. Based on the obtained partial results, we refine our computational resources by updating the priority values of image documents. Experiments have been conducted on I-FGM system with image retrieval. The results show that I-FGM outperforms its control systems. Also, in this paper we present theoretical analysis of the systems with a focus on performance. Based on probability theory, we provide models and predictions of the average performance of the I-FGM system and its two control systems, as well as the systems without partial processing.

  11. Noise properties of reconstructed images in a kilo-voltage on-board imaging system with iterative reconstruction techniques: a phantom study.

    PubMed

    Lee, S; Kim, H-J

    2014-05-01

    X-ray computed tomography (CT) images obtained with a kilo-voltage (kV) on-board imaging (OBI) system improve the accuracy of patient setup and treatment planning. The use of iterative reconstruction techniques (IRTs) for CT imaging can also reduce radiation dose compared to analytic reconstruction techniques. Despite these improvements, the image quality varies with IRTs, and the noise structure of reconstructed images can be distorted by IRTs. In this study, the noise properties and spatial resolution of the images reconstructed by IRTs were evaluated in terms of conventional noise metrics, high-order statistics, noise spectral density (NSD) and modulation transfer function (MTF) at different radiation doses. A kV OBI system mounted on a Varian Trilogy machine and a CATPHAN600 phantom were used to obtain projections, and the projections were reconstructed by Feldkamp (FDK), algebraic reconstruction technique (ART), maximum-likelihood expectation-maximization (MLEM) and total variation (TV) minimization algorithms. The reconstructed images were compared according to mean, standard deviation, skewness, kurtosis, NSD and MTF at different radiation doses. The results demonstrated that the noise properties and spatial resolution of reconstructed images depend on the type of IRT and the radiation dose. The noise structures are altered by IRTs and can be characterized by high-order statistics and NSD, as well as conventional noise metrics. In conclusion, high-order statistics and NSD should be considered in order to provide detailed information for the images reconstructed by IRTs. Also, trade-off among noise properties, spatial resolution and contrast is important to optimize image quality obtained using IRTs. PMID:24345801

  12. Preliminary analyses of space radiation protection for lunar base surface systems

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Wilson, John W.; Townsend, Lawrence W.

    1989-01-01

    Radiation shielding analyses are performed for candidate lunar base habitation modules. The study primarily addresses potential hazards due to contributions from the galactic cosmic rays. The NASA Langley Research Center's high energy nucleon and heavy ion transport codes are used to compute propagation of radiation through conventional and regolith shield materials. Computed values of linear energy transfer are converted to biological dose-equivalent using quality factors established by the International Commision of Radiological Protection. Special fluxes of heavy charged particles and corresponding dosimetric quantities are computed for a series of thicknesses in various shield media and are used as an input data base for algorithms pertaining to specific shielded geometries. Dosimetric results are presented as isodose contour maps of shielded configuration interiors. The dose predictions indicate that shielding requirements are substantial, and an abbreviated uncertainty analysis shows that better definition of the space radiation environment as well as improvement in nuclear interaction cross-section data can greatly increase the accuracy of shield requirement predictions.

  13. Novel Hybrid Monte Carlo/Deterministic Technique for Shutdown Dose Rate Analyses of Fusion Energy Systems

    SciTech Connect

    Ibrahim, Ahmad M [ORNL] [ORNL; Peplow, Douglas E. [ORNL] [ORNL; Peterson, Joshua L [ORNL] [ORNL; Grove, Robert E [ORNL] [ORNL

    2013-01-01

    The rigorous 2-step (R2S) method uses three-dimensional Monte Carlo transport simulations to calculate the shutdown dose rate (SDDR) in fusion reactors. Accurate full-scale R2S calculations are impractical in fusion reactors because they require calculating space- and energy-dependent neutron fluxes everywhere inside the reactor. The use of global Monte Carlo variance reduction techniques was suggested for accelerating the neutron transport calculation of the R2S method. The prohibitive computational costs of these approaches, which increase with the problem size and amount of shielding materials, inhibit their use in the accurate full-scale neutronics analyses of fusion reactors. This paper describes a novel hybrid Monte Carlo/deterministic technique that uses the Consistent Adjoint Driven Importance Sampling (CADIS) methodology but focuses on multi-step shielding calculations. The Multi-Step CADIS (MS-CADIS) method speeds up the Monte Carlo neutron calculation of the R2S method using an importance function that represents the importance of the neutrons to the final SDDR. Using a simplified example, preliminarily results showed that the use of MS-CADIS enhanced the efficiency of the neutron Monte Carlo simulation of an SDDR calculation by a factor of 550 compared to standard global variance reduction techniques, and that the increase over analog Monte Carlo is higher than 10,000.

  14. Ultra-Structure database design methodology for managing systems biology data and analyses

    PubMed Central

    Maier, Christopher W; Long, Jeffrey G; Hemminger, Bradley M; Giddings, Morgan C

    2009-01-01

    Background Modern, high-throughput biological experiments generate copious, heterogeneous, interconnected data sets. Research is dynamic, with frequently changing protocols, techniques, instruments, and file formats. Because of these factors, systems designed to manage and integrate modern biological data sets often end up as large, unwieldy databases that become difficult to maintain or evolve. The novel rule-based approach of the Ultra-Structure design methodology presents a potential solution to this problem. By representing both data and processes as formal rules within a database, an Ultra-Structure system constitutes a flexible framework that enables users to explicitly store domain knowledge in both a machine- and human-readable form. End users themselves can change the system's capabilities without programmer intervention, simply by altering database contents; no computer code or schemas need be modified. This provides flexibility in adapting to change, and allows integration of disparate, heterogenous data sets within a small core set of database tables, facilitating joint analysis and visualization without becoming unwieldy. Here, we examine the application of Ultra-Structure to our ongoing research program for the integration of large proteomic and genomic data sets (proteogenomic mapping). Results We transitioned our proteogenomic mapping information system from a traditional entity-relationship design to one based on Ultra-Structure. Our system integrates tandem mass spectrum data, genomic annotation sets, and spectrum/peptide mappings, all within a small, general framework implemented within a standard relational database system. General software procedures driven by user-modifiable rules can perform tasks such as logical deduction and location-based computations. The system is not tied specifically to proteogenomic research, but is rather designed to accommodate virtually any kind of biological research. Conclusion We find Ultra-Structure offers substantial benefits for biological information systems, the largest being the integration of diverse information sources into a common framework. This facilitates systems biology research by integrating data from disparate high-throughput techniques. It also enables us to readily incorporate new data types, sources, and domain knowledge with no change to the database structure or associated computer code. Ultra-Structure may be a significant step towards solving the hard problem of data management and integration in the systems biology era. PMID:19691849

  15. Challenges and status of ITER conductor production

    NASA Astrophysics Data System (ADS)

    Devred, A.; Backbier, I.; Bessette, D.; Bevillard, G.; Gardner, M.; Jong, C.; Lillaz, F.; Mitchell, N.; Romano, G.; Vostner, A.

    2014-04-01

    Taking the relay of the large Hadron collider (LHC) at CERN, ITER has become the largest project in applied superconductivity. In addition to its technical complexity, ITER is also a management challenge as it relies on an unprecedented collaboration of seven partners, representing more than half of the world population, who provide 90% of the components as in-kind contributions. The ITER magnet system is one of the most sophisticated superconducting magnet systems ever designed, with an enormous stored energy of 51 GJ. It involves six of the ITER partners. The coils are wound from cable-in-conduit conductors (CICCs) made up of superconducting and copper strands assembled into a multistage cable, inserted into a conduit of butt-welded austenitic steel tubes. The conductors for the toroidal field (TF) and central solenoid (CS) coils require about 600 t of Nb3Sn strands while the poloidal field (PF) and correction coil (CC) and busbar conductors need around 275 t of Nb-Ti strands. The required amount of Nb3Sn strands far exceeds pre-existing industrial capacity and has called for a significant worldwide production scale up. The TF conductors are the first ITER components to be mass produced and are more than 50% complete. During its life time, the CS coil will have to sustain several tens of thousands of electromagnetic (EM) cycles to high current and field conditions, way beyond anything a large Nb3Sn coil has ever experienced. Following a comprehensive R&D program, a technical solution has been found for the CS conductor, which ensures stable performance versus EM and thermal cycling. Productions of PF, CC and busbar conductors are also underway. After an introduction to the ITER project and magnet system, we describe the ITER conductor procurements and the quality assurance/quality control programs that have been implemented to ensure production uniformity across numerous suppliers. Then, we provide examples of technical challenges that have been encountered and we present the status of ITER conductor production worldwide.

  16. Numerical and experimental analyses of the radiant heat flux produced by quartz heating systems

    NASA Technical Reports Server (NTRS)

    Turner, Travis L.; Ash, Robert L.

    1994-01-01

    A method is developed for predicting the radiant heat flux distribution produced by tungsten filament, tubular fused-quartz envelope heating systems with reflectors. The method is an application of Monte Carlo simulation, which takes the form of a random walk or ray tracing scheme. The method is applied to four systems of increasing complexity, including a single lamp without a reflector, a single lamp with a Hat reflector, a single lamp with a parabolic reflector, and up to six lamps in a six-lamp contoured-reflector heating unit. The application of the Monte Carlo method to the simulation of the thermal radiation generated by these systems is discussed. The procedures for numerical implementation are also presented. Experiments were conducted to study these quartz heating systems and to acquire measurements of the corresponding empirical heat flux distributions for correlation with analysis. The experiments were conducted such that several complicating factors could be isolated and studied sequentially. Comparisons of the experimental results with analysis are presented and discussed. Good agreement between the experimental and simulated results was obtained in all cases. This study shows that this method can be used to analyze very complicated quartz heating systems and can account for factors such as spectral properties, specular reflection from curved surfaces, source enhancement due to reflectors and/or adjacent sources, and interaction with a participating medium in a straightforward manner.

  17. Analysing the Low Quality of the Data in Lighting Control Systems

    NASA Astrophysics Data System (ADS)

    Villar, Jose R.; de La Cal, Enrique; Sedano, Javier; García-Tamargo, Marco

    Energy efficiency represents one of the main challenges in the engineering field, i.e., by means of decreasing the energy consumption due to a better design minimising the energy losses. This is particularly true in real world processes in the industry or in business, where the elements involved generate data full of noise and biases. In other fields as lighting control systems, the emergence of new technologies, as the Ambient Intelligence can be, degrades the quality data introducing linguistic values. The presence of low quality data in Lighting Control Systems is introduced through an experimentation step, in order to realise the improvement in energy efficiency that its of managing could afford. In this contribution we propose, as a future work, the use of the novel genetic fuzzy system approach to obtain classifiers and models able to deal with the above mentioned problems.

  18. A policy iteration algorithm for Markov decision processes skip-free in one direction

    E-print Network

    -run average cost is minimal? In other words, what is the optimal policy which maps S to A such that the costs of a linear system of equations at each iteration. The value iteration algorithm is faster per iteration the state space S is partitioned into M + 1 sets, labeled S0 to SM , and a transition from a state h Si

  19. A FAMILY OF RANGE RESTRICTED ITERATIVE METHODS FOR LINEAR DISCRETE ILL-POSED PROBLEMS

    E-print Network

    Reichel, Lothar

    A FAMILY OF RANGE RESTRICTED ITERATIVE METHODS FOR LINEAR DISCRETE ILL-POSED PROBLEMS L. DYKES AND L. REICHEL Abstract. The solution of large linear systems of equations with a matrix of ill. Key words. ill-posed problem, iterative method, truncated iteration 1. Introduction. This paper

  20. Comparing the performance of two iterative Learning Controllers with optimal feedback control

    Microsoft Academic Search

    James D. Ratcliffe; Paul L. Lewin; Eric Rogers

    2006-01-01

    The tracking performance of two iterative learning control algorithms is compared to that, which can be achieved by an optimal feedback controller. P-type iterative learning control in parallel with a proportional feedback controller is compared with norm-optimal iterative learning control, then both ILC systems are compared with the performance achieved by an optimal feedback controller. Considering that the ILC plus

  1. NASA Ames three-dimensional potential flow analyses system (POTFAN) boundary condition code (BCDN), version 1

    NASA Technical Reports Server (NTRS)

    Davis, J. E.; Medan, R. T.

    1977-01-01

    This segment of the POTFAN system is used to generate right hand sides (boundary conditions) of the system of equations associated with the flow field under consideration. These specified flow boundary conditions are encountered in the oblique derivative boundary value problem (boundary value problem of the third kind) and contain the Neumann boundary condition as a special case. Arbitrary angle of attack and/or sideslip and/or rotation rates may be specified, as well as an arbitrary, nonuniform external flow field and the influence of prescribed singularity distributions.

  2. Analyses of a continuum traffic flow model for a nonlane-based system

    NASA Astrophysics Data System (ADS)

    Gupta, Arvind Kumar; Dhiman, Isha

    2014-03-01

    We develop a heterogeneous continuum model based upon a car-following model for a nonlane-based system taking lateral separation into account. The criterion for linear stability analysis and traveling wave solution of the homogeneous case is studied. The consideration of the lateral separation not only stabilizes the flow but also shrinks the critical region. For heterogeneous case, the fundamental diagram is examined for two different equilibrium speed-density functions and the effect of lane width is investigated for different compositions of heterogeneous traffic. The theoretical findings agree well with the results of numerical simulation which justifies the applicability of the model to a nonlane-based system.

  3. Parent Stars of Extrasolar Planets VI: Abundance Analyses of 20 New Systems

    E-print Network

    G. Gonzalez; C. Laws; S. Tyagi; B. E. Reddy

    2000-10-10

    The results of new spectroscopic analyses of 20 recently reported extrasolar planet parent stars are presented. The companion of one of these stars, HD 10697, has recently been shown to have a mass in the brown dwarf regime; we find [Fe/H] $= +0.16$ for it. For the remaining sample, we derive [Fe/H] estimates ranging from -0.41 to $+0.37$, with an average value of $+0.18 \\pm 0.19$. If we add the 13 stars included in the previous papers of this series and 6 other stars with companions below the 11 M$_{\\rm Jup}$ limit from the recent studies of Santos et al., we derive $ = +0.17 \\pm 0.20$. Among the youngest stars with planets with F or G0 spectral types, [Fe/H] is systematically larger than young field stars of the same Galactocentric distance by 0.15 to 0.20 dex. This confirms the recent finding of Laughlin that the most massive stars with planets are systematically more metal rich than field stars of the same mass. We interpret these trends as supporting a scenario in which these stars accreted high-Z material after their convective envelopes shrunk to near their present masses. Correcting these young star metallicities by 0.15 dex still does not fully account for the difference in mean metallicity between the field stars and the full parent stars sample. The stars with planets appear to have smaller [Na/Fe], [Mg/Fe], and [Al/Fe] values than field dwarfs of the same [Fe/H]. They do not appear to have significantly different values of [O/Fe], [Si/Fe], [Ca/Fe], or [Ti/Fe], though.

  4. First light curve analyses of binary systems AO Aqr, CW Aqr and ASAS 012206-4924.7

    NASA Astrophysics Data System (ADS)

    Ula?, B.; Ulusoy, C.

    2015-11-01

    Using the data from the public database of the All Sky Automated Survey (ASAS) we performed the very first light curve analyses of the three eclipsing binary systems AO Aqr, CW Aqr and ASAS 012206-4924.7. The physical parameters of the systems were determined by the PHOEBE (Prša and Zwitter, 2005) software. From an analysis of the ASAS data it was concluded that AO Aqr was found to be a contact binary system while CW Aqr and ASAS 012206-4924.7 were found to be near-contact and detached binaries, respectively. Finally, the locations of the components, corresponding to the estimated physical parameters, in the HR diagram were also discussed.

  5. Analyses of Energy, Exergy and Sustainable Development of Vapor Compression Refrigeration System Using Hydrocarbon

    Microsoft Academic Search

    J. U. Ahamed; R Saidur; H. H. Masjuki; M. A. Sattar

    2012-01-01

    Hydrocarbons being natural fluid have drawn much attention to the scientists and researchers for the application as a sustainable material for the vapor compression refrigeration system. This paper presents a comparison of the energetic and exergetic performances of a domestic refrigerator using pure butane and iso-butane as refrigerants. The thermodynamic performances such as exergy destruction or losses, exergy efficiency, and

  6. An Earthquake Prediction System Using The Time Series Analyses of Earthquake Property And Crust Motion

    SciTech Connect

    Takeda, Fumihide [Takeda Engineering Consultant Inc., 2-14-23 Ujina Miyuki, Hiroshima, 734-0015 (Japan); Takeo, Makoto [Department of Physics, Portland State University, P.O. Box 751, Portland, OR, 97207-0751 (United States)

    2004-12-09

    We have developed a short-term deterministic earthquake (EQ) forecasting system similar to those used for Typhoons and Hurricanes, which has been under a test operation at website http://www.tec21.jp/ since June of 2003. We use the focus and crust displacement data recently opened to the public by Japanese seismograph and global positioning system (GPS) networks, respectively. Our system divides the forecasting area into the five regional areas of Japan, each of which is about 5 deg. by 5 deg. We have found that it can forecast the focus, date of occurrence and magnitude (M) of an impending EQ (whose M is larger than about 6), all within narrow limits. We have two examples to describe the system. One is the 2003/09/26 EQ of M 8 in the Hokkaido area, which is of hindsight. Another is a successful rollout of the most recent forecast on the 2004/05/30 EQ of M 6.7 off coast of the southern Kanto (Tokyo) area.

  7. Systems Performance Analyses of Alaska Wind-Diesel Projects; Selawik, Alaska (Fact Sheet)

    SciTech Connect

    Baring-Gould, I.

    2009-04-01

    This fact sheet summarizes a systems performance analysis of the wind-diesel project in Selawik, Alaska. Data provided for this project include community load data, wind turbine output, diesel plant output, thermal load data, average wind speed, average net capacity factor, optimal net capacity factor based on Alaska Energy Authority wind data, average net wind penetration, and estimated fuel savings.

  8. An integrated assessment approach to conduct analyses of climate change impacts on whole-farm systems

    Microsoft Academic Search

    M. Rivington; K. B. Matthews; Gianni Bellocchi; K. Buchan; C. O. Stöckle; Marcello Donatelli

    2007-01-01

    This paper argues that an integrated assessment approach, combining simulation modelling with deliberative processes involving decision makers and other stakeholders, has the potential to generate credible and relevant assessments of climate change impacts on farming-systems. The justification for the approach proposed is that while simulation modelling provides an effective way of exploring the range of possible impacts of climate change

  9. Analyse des Correlations entre Pannes dans les Syst`emes de Stockage Pair-`a-Pair

    E-print Network

    Paris-Sud XI, Université de

    `eme (calcul de tous les moments) mais aussi de le simuler efficacement, car il est ind´ependant de la taille, as they usually have a lower storage space overhead than replication [3]. We study the following questions: How system. We provide a mathematical analysis This work was partially funded by the European project IST FET

  10. Parent Ratings of Children's Social Skills: Longitudinal Psychometric Analyses of the Social Skills Rating System

    ERIC Educational Resources Information Center

    Van Horn, M. Lee; Atkins-Burnett, Sally; Karlin, Emilie; Ramey, Sharon Landesman; Snyder, Scott

    2007-01-01

    The assessment of children's social skills is an important task for school psychologists in both applied and research settings. The present study examines the psychometric properties of parent ratings of the Social Skills Rating System (SSRS), in kindergarten through third grades, testing for measurement differences between boys and girls, between…

  11. Nontarget screening analyses of organic contaminants in river systems as a base for monitoring measures

    Microsoft Academic Search

    J. Schwarzbauer

    2009-01-01

    Organic contaminants discharged to the aquatic environment exhibit a high diversity with respect to their molecular structures and the resulting physico-chemical properties. The chemical analysis of anthropogenic contamination in river systems is still an important feature, especially with respect to (i) the identification and structure elucidation of novel contaminants, (ii) to the characterisation of their environmental behaviour and (iii) to

  12. High resolution interrogation system for fiber Bragg grating (FBG) sensor application using radio frequency spectrum analyser

    NASA Astrophysics Data System (ADS)

    Muhammad, F. D.; Zulkifli, M. Z.; Harun, S. W.; Ahmad, H.

    2013-05-01

    In this paper, we propose a fiber Bragg grating (FBG) interrogation system for high resolution sensor application based on radio frequency (RF) generation technique by beating a single longitudinal mode (SLM) fiber ring laser with an external tunable laser source (TLS). The external TLS provides a constant wavelength (CW), functioning as the reference signal for the frequency beating technique. The TLS used has a constant output power and wavelength over time. The sensor signal is provided by the reflected wavelength of a typical fiber Bragg grating (FBG) in the SLM fiber ring laser, which consists of a 1 m long highly doped Erbium doped fiber as the gain medium. The key to ensure the SLM laser oscillation is the role of graphene as saturable absorber which is opposed to the commonly used unpumped erbiumdoped fiber and this consequently contributes to the simple and short cavity design of our proposed system. The signal from the SLM fiber ring laser, which is generated by the FBG in response to external changes, such as temperature, strain, air humidity and air movement, is heterodyned with the CW signal from the TLS at a 6 GHz photodetector using a 3-dB fused coupler to generate the frequency beating. This proposed system is experimentally demonstrated as a temperature sensor and the results shows that the frequency response of the system towards the changes in temperature is about 1.3 GHz/°C, taking into account the resolution bandwidth of 3 MHz of the radio frequency spectrum analyzer (RFSA).

  13. Peptidomic and proteomic analyses of the systemic immune response of Drosophila

    Microsoft Academic Search

    Francine Levy; David Rabel; Maurice Charlet; Philippe Bulet; Jules A. Hoffmann; Laurence Ehret-Sabatier

    2004-01-01

    Insects have developed an efficient host defense against microorganisms, which involves humoral and cellular mechanisms. Numerous data highlight similarities between defense responses of insects and innate immunity of mammals. The fruit fly, Drosophila melanogaster, is a favorable model system for the analysis of the first line defense against microorganisms. Taking advantages of improvements in mass spectrometry (MS), two-dimensional (2D) gel

  14. Characterization and Analyses of Valves, Feed Lines and Tanks used in Propellant Delivery Systems at NASA SSC

    NASA Technical Reports Server (NTRS)

    Ryan, Harry M.; Coote, David J.; Ahuja, Vineet; Hosangadi, Ashvin

    2006-01-01

    Accurate modeling of liquid rocket engine test processes involves assessing critical fluid mechanic and heat and mass transfer mechanisms within a cryogenic environment, and accurately modeling fluid properties such as vapor pressure and liquid and gas densities as a function of pressure and temperature. The Engineering and Science Directorate at the NASA John C. Stennis Space Center has developed and implemented such analytic models and analysis processes that have been used over a broad range of thermodynamic systems and resulted in substantial improvements in rocket propulsion testing services. In this paper, we offer an overview of the analyses techniques used to simulate pressurization and propellant fluid systems associated with the test stands at the NASA John C. Stennis Space Center. More specifically, examples of the global performance (one-dimensional) of a propellant system are provided as predicted using the Rocket Propulsion Test Analysis (RPTA) model. Computational fluid dynamic (CFD) analyses utilizing multi-element, unstructured, moving grid capability of complex cryogenic feed ducts, transient valve operation, and pressurization and mixing in propellant tanks are provided as well.

  15. Development of advanced inductive scenarios for ITER

    NASA Astrophysics Data System (ADS)

    Luce, T. C.; Challis, C. D.; Ide, S.; Joffrin, E.; Kamada, Y.; Politzer, P. A.; Schweinzer, J.; Sips, A. C. C.; Stober, J.; Giruzzi, G.; Kessel, C. E.; Murakami, M.; Na, Y.-S.; Park, J. M.; Polevoi, A. R.; Budny, R. V.; Citrin, J.; Garcia, J.; Hayashi, N.; Hobirk, J.; Hudson, B. F.; Imbeaux, F.; Isayama, A.; McDonald, D. C.; Nakano, T.; Oyama, N.; Parail, V. V.; Petrie, T. W.; Petty, C. C.; Suzuki, T.; Wade, M. R.; the ITPA Integrated Operation Scenario Topical Group Members; the ASDEX-Upgrade Team; the DIII-D Team; EFDA Contributors, JET; the JT-60U Team

    2014-01-01

    Since its inception in 2002, the International Tokamak Physics Activity topical group on Integrated Operational Scenarios (IOS) has coordinated experimental and modelling activity on the development of advanced inductive scenarios for applications in the ITER tokamak. The physics basis and the prospects for applications in ITER have been advanced significantly during that time, especially with respect to experimental results. The principal findings of this research activity are as follows. Inductive scenarios capable of higher normalized pressure (?N ? 2.4) than the ITER baseline scenario (?N = 1.8) with normalized confinement at or above the standard H-mode scaling are well established under stationary conditions on the four largest diverted tokamaks (AUG, DIII-D, JET, JT-60U), demonstrated in a database of more than 500 plasmas from these tokamaks analysed here. The parameter range where high performance is achieved is broad in q95 and density normalized to the empirical density limit. MHD modes can play a key role in reaching stationary high performance, but also define the limits to achieved stability and confinement. Projection of performance in ITER from existing experiments uses empirical scalings and theory-based modelling. The status of the experimental validation of both approaches is summarized here. The database shows significant variation in the energy confinement normalized to standard H-mode confinement scalings, indicating the possible influence of additional physics variables absent from the scalings. Tests using the available information on rotation and the ratio of the electron and ion temperatures indicate neither of these variables in isolation can explain the variation in normalized confinement observed. Trends in the normalized confinement with the two dimensionless parameters that vary most from present-day experiments to ITER, gyroradius and collision frequency, are significant. Regression analysis on the multi-tokamak database has been performed, but it appears that the database is not conditioned sufficiently well to yield a new scaling for this type of plasma. Coordinated experiments on size scaling using the dimensionless parameter scaling approach find a weaker scaling with normalized gyroradius than the standard H-mode scaling. Preliminary studies on scaling with collision frequency show a favourable scaling stronger than the standard H-mode scaling. Coordinated modelling activity has resulted in successful benchmarking of modelling codes in the ITER regime. Validation of transport models using these codes on present-day experiments is in progress, but no single model has been shown to capture the variations seen in the experiments. However, projection to ITER using these models is in general agreement with the favourable projections found with the empirical scalings.

  16. Considering lighting system performance and HVAC interactions in lighting retrofit analyses

    SciTech Connect

    Franconi, E.; Rubinstein, F.

    1991-10-01

    The performance of several typical fluorescent lighting retrofits are examined using analysis methods of varying sophistication. Estimates of energy and lighting performance based on the simple non-application specific data generally available tend to overestimate the energy savings obtained with the various retrofits by 10-30%. Adding a simple correction to account for cooling benefits exacerbates the error unless heating penalties are also considered. An analysis method that takes into account the thermal application factor of the lighting system shows that the error is typically due to systematically overestimating the energy usage of the original lighting system. If thermal application factor is considered, then detailed HVAC calculations do not significantly improve the energy-savings estimate.

  17. Energy and exergy analyses of a biomass-based hydrogen production system.

    PubMed

    Cohce, M K; Dincer, I; Rosen, M A

    2011-09-01

    In this paper, a novel biomass-based hydrogen production plant is investigated. The system uses oil palm shell as a feedstock. The main plant processes are biomass gasification, steam methane reforming and shift reaction. The modeling of the gasifier uses the Gibbs free energy minimization approach and chemical equilibrium considerations. The plant, with modifications, is simulated and analyzed thermodynamically using the Aspen Plus process simulation code (version 11.1). Exergy analysis, a useful tool for understanding and improving efficiency, is used throughout the investigation, in addition to energy analysis. The overall performance of the system is evaluated, and its efficiencies become 19% for exergy efficiency and 22% energy efficiency while the gasifier cold gas efficiency is 18%. PMID:21724387

  18. Analyses of geometrically nonlinear structures using a Langrangian strain representation and a convected coordinate system 

    E-print Network

    Cheung, Shing Tak

    1974-01-01

    the updated coordinate system x-y' is the reference system, all the c and q terms drop out. Therefore, Eq. 32 is reduced to 66c = ? )??4? (66q , 66q ) L?1' -y/L $2, $'3 $5 4Q (66 2, 66q3, 66q5, 66q6 + ( &??&?(6q ?dq?( ~??&?(6&q ?66q? 1 L ?2' 3' 5'4Q 2...) (L?pl $J 66 I, 66 4 ) (L 42~'4 (36) ( q, q3 ?5 dq, ?(-, 42'. 43 45 46. ?dq2. ?q, ?q, ?6? 24 326 NL 1 and Bdq Mq 2 0 0 2(2 (2(3 0 symmetric 0 0 (3(3 0 0 4346 (656 (37) Equations 35, 36 and 37 lead directly from Eq. 14 to the more...

  19. NUMERICAL ANALYSES FOR TREATING DIFFUSION IN SINGLE-, TWO-, AND THREE-PHASE BINARY ALLOY SYSTEMS

    NASA Technical Reports Server (NTRS)

    Tenney, D. R.

    1994-01-01

    This package consists of a series of three computer programs for treating one-dimensional transient diffusion problems in single and multiple phase binary alloy systems. An accurate understanding of the diffusion process is important in the development and production of binary alloys. Previous solutions of the diffusion equations were highly restricted in their scope and application. The finite-difference solutions developed for this package are applicable for planar, cylindrical, and spherical geometries with any diffusion-zone size and any continuous variation of the diffusion coefficient with concentration. Special techniques were included to account for differences in modal volumes, initiation and growth of an intermediate phase, disappearance of a phase, and the presence of an initial composition profile in the specimen. In each analysis, an effort was made to achieve good accuracy while minimizing computation time. The solutions to the diffusion equations for single-, two-, and threephase binary alloy systems are numerically calculated by the three programs NAD1, NAD2, and NAD3. NAD1 treats the diffusion between pure metals which belong to a single-phase system. Diffusion in this system is described by a one-dimensional Fick's second law and will result in a continuous composition variation. For computational purposes, Fick's second law is expressed as an explicit second-order finite difference equation. Finite difference calculations are made by choosing the grid spacing small enough to give convergent solutions of acceptable accuracy. NAD2 treats diffusion between pure metals which form a two-phase system. Diffusion in the twophase system is described by two partial differential equations (a Fick's second law for each phase) and an interface-flux-balance equation which describes the location of the interface. Actual interface motion is obtained by a mass conservation procedure. To account for changes in the thicknesses of the two phases as diffusion progresses, a variable grid technique developed by Murray and Landis is employed. These equations are expressed in finite difference form and solved numerically. Program NAD3 treats diffusion between pure metals which form a two-phase system with an intermediate third phase. Diffusion in the three-phase system is described by three partial differential expressions of Fick's second law and two interface-flux-balance equations. As with the two-phase case, a variable grid finite difference is used to numerically solve the diffusion equations. Computation time is minimized without sacrificing solution accuracy by treating the three-phase problem as a two-phase problem when the thickness of the intermediate phase is less than a preset value. Comparisons between these programs and other solutions have shown excellent agreement. The programs are written in FORTRAN IV for batch execution on the CDC 6600 with a central memory requirement of approximately 51K (octal) 60 bit words.

  20. Calculations & Analyses to Support K West Basin Canister Cleaning System Project A-2A

    SciTech Connect

    SMITH, S.O.

    2001-09-17

    Approximately 2,300 metric tons of Spent Nuclear Fuel (SNF) are currently stored within two water filled pools, the 105 K East (KE) fuel storage basin and the 105 K West (KW) fuel storage basin at the US. Department of Energy, Richland Operations Office. The SNF Project is responsible for operation of the K Basins and for the materials within them. A subproject to the SNF Project is the Debris Removal Subproject, which is responsible for removal of empty canisters and lids form the basins. This revised document reviews calculations, originally prepared by COGEMA Engineering, for changes due to relocation of the Canister Cleaning System (CCS) from the Dummy Elevator Pit to the Tech View Pit Area and the elimination of the High Pressure Cleaning System.

  1. Development and Evaluation of a Formal-Analytical Usability Analysing Tool for Medical Devices and Systems

    Microsoft Academic Search

    A. Janß; W. Lauer; K. Radermacher

    \\u000a Technological progress in the field of Computer-Assisted Surgery (CAS) not only leads to an enhancement in efficiency and\\u000a effectiveness concerning therapeutic results but also to a change of the Human-Computer-Interaction characteristics in the\\u000a operating room (OR). Deficiencies in the use process of CAS systems bring along high potential for hazardous human-induced\\u000a failures implicating higher risks for patients and physicians during

  2. Sequence and phylogenetic analyses of the twin-arginine targeting (Tat) protein export system

    Microsoft Academic Search

    Ming-Ren Yen; Yi-Hsiung Tseng; Erin H. Nguyen; Long-Fe Wu; Milton H. Saier Jr

    2002-01-01

    . Twin-arginine targeting (Tat) protein secretion systems consist of two protein types, members of the TatA and TatC families. Homologues of these proteins are found in many archaea, bacteria, chloroplasts and mitochondria. Every prokaryotic organism with a fully sequenced genome exhibits either neither family member, or between one and three paralogues of these two family members. The Arabidopsis thaliana genome

  3. Modelisation et analyse des syst`emes Duree: 4h. Une feuille par question.

    E-print Network

    Catholique de Louvain, Université

    ´eaire mais temps-variant ; (b) temps-invariant mais non-lin´eaire ; (c) non-lin´eaire et temps variant. 3 ; (b) l'image n'est pas un espace vectoriel. Justifier vos r´eponses. Question 2 Un syst`eme LTI[n - 1] - 3y[n - 2] + u[n - 1]. 1. Trouver la fonction de transfert H(z), ses p^oles et ses z´eros, et

  4. Modelisation et analyse des syst`emes Duree: 4h. Une feuille par question.

    E-print Network

    Catholique de Louvain, Université

    -dessous avec 0 b. a b - - u + + y+ + 1. D´eterminer la fonction de transfert du syst`eme. 2. Calculer la`eme de mani`ere `a ce que la nouvelle fonction de transfert comporte deux p^oles et deux z´eros. Justifier et dessiner le nouveau bloc- diagramme. 5. Choisir des valeurs num´eriques pour a et b (0 b

  5. Analyses of Entry Mechanisms of Novel Emerging Viruses Using Pseudotype VSV System.

    PubMed

    Tani, Hideki

    2014-06-01

    Emerging infectious diseases include newly identified diseases caused by previously unknown organisms or diseases found in new and expanding geographic areas. Viruses capable of causing clinical disease associated with fever and bleeding are referred to as viral hemorrhagic fevers (VHFs). Arenaviruses and Bunyaviruses, both belonging to families classified as VHFs are considered major etiologies of hemorrhagic fevers caused by emerging viruses; having significant clinical and public health impact. Because these viruses are categorized as Biosafety Level (BSL) 3 and 4 pathogens, restricting their use, biological studies including therapeutic drug and vaccine development have been impeded. Due to these restrictions and the difficulties in handling such live viruses, pseudotype viruses bearing envelope proteins of VHF viruses have been developed using vesicular stomatitis virus (VSV) as a surrogate system. Here, we report the successful developments of two pseudotype VSV systems; bearing the envelope proteins of Lujo virus and severe fever with thrombocytopenia syndrome (SFTS) virus, both recently identified viruses of the family Arenaviridae and Bunyaviridae, respectively. My presentation will summarize the characterization of the envelope proteins of Lujo virus including its cellular receptor use and cell entry mechanisms. In addition, I will also present a brief introduction of SFTS reported in Japan and the diagnostic studies in progress using these newly pseudotype VSV system. PMID:25425954

  6. Analyses of Entry Mechanisms of Novel Emerging Viruses Using Pseudotype VSV System

    PubMed Central

    2014-01-01

    Emerging infectious diseases include newly identified diseases caused by previously unknown organisms or diseases found in new and expanding geographic areas. Viruses capable of causing clinical disease associated with fever and bleeding are referred to as viral hemorrhagic fevers (VHFs). Arenaviruses and Bunyaviruses, both belonging to families classified as VHFs are considered major etiologies of hemorrhagic fevers caused by emerging viruses; having significant clinical and public health impact. Because these viruses are categorized as Biosafety Level (BSL) 3 and 4 pathogens, restricting their use, biological studies including therapeutic drug and vaccine development have been impeded. Due to these restrictions and the difficulties in handling such live viruses, pseudotype viruses bearing envelope proteins of VHF viruses have been developed using vesicular stomatitis virus (VSV) as a surrogate system. Here, we report the successful developments of two pseudotype VSV systems; bearing the envelope proteins of Lujo virus and severe fever with thrombocytopenia syndrome (SFTS) virus, both recently identified viruses of the family Arenaviridae and Bunyaviridae, respectively. My presentation will summarize the characterization of the envelope proteins of Lujo virus including its cellular receptor use and cell entry mechanisms. In addition, I will also present a brief introduction of SFTS reported in Japan and the diagnostic studies in progress using these newly pseudotype VSV system. PMID:25425954

  7. Envelope and order domain analyses of a nonlinear torsional system decelerating under multiple order frictional torque

    NASA Astrophysics Data System (ADS)

    Sen, Osman Taha; Dreyer, Jason T.; Singh, Rajendra

    2013-02-01

    The broader goal of this article is to re-examine the classical machinery shut down vibration problem in the context of a two degree of freedom nonlinear torsional system that essentially describes a braking system example. In particular, resonant amplifications during deceleration, as excited by a multi-order rotor surface distortion and pad friction regime, are investigated using a nonlinear model, and the order domain predictions are successfully compared with an experiment. Then a quasi-linear model at higher speeds is proposed and analytically solved to obtain closed form expressions for speed-dependent torque as well as its envelope curve. The Hilbert transform is also utilized to successfully calculate the envelope curves of both quasi-linear and nonlinear systems. Finally, the multi-term harmonic balance method is applied to construct semi-analytical solutions of the nonlinear torsional model, and the order domain results are successfully compared with measurements. New analytical solutions provide more insight to the speed-dependent characteristics given instantaneous frequency excitation.

  8. Integrating medical imaging analyses through a high-throughput bundled resource imaging system

    NASA Astrophysics Data System (ADS)

    Covington, Kelsie; Welch, E. Brian; Jeong, Ha-Kyu; Landman, Bennett A.

    2011-03-01

    Exploitation of advanced, PACS-centric image analysis and interpretation pipelines provides well-developed storage, retrieval, and archival capabilities along with state-of-the-art data providence, visualization, and clinical collaboration technologies. However, pursuit of integrated medical imaging analysis through a PACS environment can be limiting in terms of the overhead required to validate, evaluate and integrate emerging research technologies. Herein, we address this challenge through presentation of a high-throughput bundled resource imaging system (HUBRIS) as an extension to the Philips Research Imaging Development Environment (PRIDE). HUBRIS enables PACS-connected medical imaging equipment to invoke tools provided by the Java Imaging Science Toolkit (JIST) so that a medical imaging platform (e.g., a magnetic resonance imaging scanner) can pass images and parameters to a server, which communicates with a grid computing facility to invoke the selected algorithms. Generated images are passed back to the server and subsequently to the imaging platform from which the images can be sent to a PACS. JIST makes use of an open application program interface layer so that research technologies can be implemented in any language capable of communicating through a system shell environment (e.g., Matlab, Java, C/C++, Perl, LISP, etc.). As demonstrated in this proof-of-concept approach, HUBRIS enables evaluation and analysis of emerging technologies within well-developed PACS systems with minimal adaptation of research software, which simplifies evaluation of new technologies in clinical research and provides a more convenient use of PACS technology by imaging scientists.

  9. Clarifying Objectives and Results of Equivalent System Mass Analyses for Advanced Life Support

    NASA Technical Reports Server (NTRS)

    Levri, Julie A.; Drysdale, Alan E.

    2003-01-01

    This paper discusses some of the analytical decisions that an investigator must make during the course of a life support system trade study. Equivalent System Mass (ESM) is often applied to evaluate trade study options in the Advanced Life Support (ALS) Program. ESM can be used to identify which of several options that meet all requirements are most likely to have lowest cost. It can also be used to identify which of the many interacting parts of a life support system have the greatest impact and sensitivity to assumptions. This paper summarizes recommendations made in the newly developed ALS ESM Guidelines Document and expands on some of the issues relating to trade studies that involve ESM. In particular, the following three points are expounded: 1) The importance of objectives: Analysis objectives drive the approach to any trade study, including identification of assumptions, selection of characteristics to compare in the analysis, and the most appropriate techniques for reflecting those characteristics. 2) The importance of results inferprefafion: The accuracy desired in the results depends upon the analysis objectives, whereas the realized accuracy is determined by the data quality and degree of detail in analysis methods. 3) The importance of analysis documentation: Documentation of assumptions and data modifications is critical for effective peer evaluation of any trade study. ESM results are analysis-specific and should always be reported in context, rather than as solitary values. For this reason, results reporting should be done with adequate rigor to allow for verification by other researchers.

  10. Multiple 3D reference system analyses for Phobos grooves, a novel approach

    NASA Astrophysics Data System (ADS)

    Simioni, Emanuele; Pajola, Maurizio; Massironi, Matteo; Cremonese, Gabriele

    2015-04-01

    Grooves analysis has represented in the last decade a robust method for geomorphological study of small bodies, as is the case for asteroids 951 Gaspra (Veverka et al., 1994), 243 Ida (Belton et al., 1994), 433 Eros (Thomas et al., (2002), Buczkowski et al., 2008), 21 Lutetia (Massironi et al., 2011, *Besse et al., 2014*) and 4 Vesta (Buczkowski et al., 2*012). Hence, such source of information can be deeper used for a novel approach presented on Phobos with the aim of providing more hints on its harshly debated origin. Stereo-plots and cyclographs represent two methods, unified under the name of stereographic projections, commonly used to describe the statistic of the orientations (dip-angle and dip-direction) of different planes with respect to cardinal points and a reference horizontal plane (Bucher, 1944; Phillips, 1954; Ragan, 1985). However this reference system is ambiguous for any applications on small irregular bodies such as asteroids or comets since it does not permit to highlight systems of parallel anisotropies and to have an idea of their distribution with respect to a given surface feature (for example an impact crater). In this work we show a novel approach for stereographic projections focusing to a multi-reference system. The multi-reference system can be centered on a specific surface feature such as a crater and can alternatively use an absolute reference plane containing the center of figure of the body (to retrieve systems of parallel anisotropies) or a relative horizontal plane (to understand the distribution of the anisotropies with respect to the central feature). In this way we are able to well define the distribution of the grooves expected to be originated from a impact cratering event in a small body. Following this methodology, we have extracted 352 3D fracture planes from the attitudes of the grooves over the surface topography of Phobos and, for each plane, the local surface versor has been defined. Consequently, stereo-plots on absolute and relative reference systems have been retrieved to recognize the mutual orientation of the different joint sets and their relationship with respect to specific regions where major impacts were recorded. Assuming that grooves could be expression of fracture and joints and by retrieving planes and related stereo plots from the linear features at the surface, we recognized that only a minimum percentage with respect to the total amount of grooves is related to major craters. On the other hand two main cross-cutting parallel sets, unrelated to any crater, have been found. This observation allowed us to propose a new formation scenario for Phobos grooves which has important consequences on the origin of Phobos itself: a single shard formation from an ancient fractured parent body. Such scenario has never been taken into consideration for Phobos and has two major consequences: one side the observed grooves distribution could be explained as the result of possible major impacts on the larger parent body, which were inherited by the "Phobos shard", while on the other side could hint towards an ancient asteroidal origin of this satellite.

  11. Precursor systems analyses of automated highway systems. AHS systems analysis. Volume 4. Final report, 9 September 1993-30 October 1994

    SciTech Connect

    Elias, J.A.

    1995-06-01

    The program described by this eight-volume report, a resource materials document type, identified the issues and risks associated with the potential design, development, and operation of an Automated Highway System (AHS), a highway system that utilizes limited access roadways and provides `hands off` driving. The AHS effort was conducted by a team formed and directed by the Calspan Advanced Technology Center. Primary Team members included Calspan, Parsons Brinckerhoff, Dunn Engineering Associates, and Princeton University. Supporting members of the team were BMV, New York State Thruway Authority, New York State Department of Transportation, Massachusetts Department of Transportation, the New Jersey Department of Transportation, Boston Research, Vitro Corporation, and Michael P. Walsh of Walsh Associates. Calspan provided overall management and integration of the program and had lead responsibility for 5 of the 17 tasks. Parsons Brinkerhoff provided transportation planning and engineering expertise and had lead responsibility for 5 tasks. Dunn Engineering provided traffic engineering expertise and had lead responsibility on 2 tasks. Princeton supported the areas of transportation planning and automated control. The 17 task reports (A through P plus representative Systems Configurations) are organized into 8 volumes. This volume, which describes AHS systems analyses, covers 5 tasks.

  12. Integrating Medical Imaging Analyses through a High-throughput Bundled Resource Imaging System.

    PubMed

    Covington, Kelsie; Welch, E Brian; Jeong, Ha-Kyu; Landman, Bennett A

    2011-01-01

    Exploitation of advanced, PACS-centric image analysis and interpretation pipelines provides well-developed storage, retrieval, and archival capabilities along with state-of-the-art data providence, visualization, and clinical collaboration technologies. However, pursuit of integrated medical imaging analysis through a PACS environment can be limiting in terms of the overhead required to validate, evaluate and integrate emerging research technologies. Herein, we address this challenge through presentation of a high-throughput bundled resource imaging system (HUBRIS) as an extension to the Philips Research Imaging Development Environment (PRIDE). HUBRIS enables PACS-connected medical imaging equipment to invoke tools provided by the Java Imaging Science Toolkit (JIST) so that a medical imaging platform (e.g., a magnetic resonance imaging scanner) can pass images and parameters to a server, which communicates with a grid computing facility to invoke the selected algorithms. Generated images are passed back to the server and subsequently to the imaging platform from which the images can be sent to a PACS. JIST makes use of an open application program interface layer so that research technologies can be implemented in any language capable of communicating through a system shell environment (e.g., Matlab, Java, C/C++, Perl, LISP, etc.). As demonstrated in this proof-of-concept approach, HUBRIS enables evaluation and analysis of emerging technologies within well-developed PACS systems with minimal adaptation of research software, which simplifies evaluation of new technologies in clinical research and provides a more convenient use of PACS technology by imaging scientists. PMID:21841899

  13. Study on the Tritium Behaviors in the VHTR System. Part 2: Analyses on the Tritium Behaviors in the VHTR/HTSE System

    SciTech Connect

    Eung Soo Kim; Chang Ho Oh; Mike Patterson

    2010-07-01

    Tritium behaviors in the very high temperature gas reactor (VHTR)/high temperature steam electrolysis (HTSE) system have been analyzed by the TPAC code developed by Idaho National Laboratory (INL). The reference system design and conditions were based on the indirect parallel configuration between a VHTR and a HTSE. The analyses were based on the Sobol method, a modern uncertainty and sensitivity analyses methods using variance decomposition and Monte Carlo methods. Totally, 14 parameters have been taken into accounts associated with tritium sources, heat exchangers, purification systems, and temperatures. Two sensitivity indices (first order index and total index) were considered, and 15,360 samples were totally used for solution convergence. As a result, important parameters that affect tritium concentration in the hydrogen product have been identified and quantified with the rankings. Several guidelines and recommendations for reducing modeling uncertainties have been also provided throughout the discussions along with some useful ideas for mitigating tritium contaminations in the hydrogen product.

  14. Phytophthora community structure analyses in Oregon nurseries inform systems approaches to disease management.

    PubMed

    Parke, Jennifer L; Knaus, Brian J; Fieland, Valerie J; Lewis, Carrie; Grünwald, Niklaus J

    2014-10-01

    ABSTRACT Nursery plants are important vectors for plant pathogens. Understanding what pathogens occur in nurseries in different production stages can be useful to the development of integrated systems approaches. Four horticultural nurseries in Oregon were sampled every 2 months for 4 years to determine the identity and community structure of Phytophthora spp. associated with different sources and stages in the nursery production cycle. Plants, potting media, used containers, water, greenhouse soil, and container yard substrates were systematically sampled from propagation to the field. From 674 Phytophthora isolates recovered, 28 different species or taxa were identified. The most commonly isolated species from plants were Phytophthora plurivora (33%), P. cinnamomi (26%), P. syringae (19%), and P. citrophthora (11%). From soil and gravel substrates, P. plurivora accounted for 25% of the isolates, with P. taxon Pgchlamydo, P. cryptogea, and P. cinnamomi accounting for 18, 17, and 15%, respectively. Five species (P. plurivora, P. syringae, P. taxon Pgchlamydo, P. gonapodyides, and P. cryptogea) were found in all nurseries. The greatest diversity of taxa occurred in irrigation water reservoirs (20 taxa), with the majority of isolates belonging to internal transcribed spacer clade 6, typically including aquatic opportunists. Nurseries differed in composition of Phytophthora communities across years, seasons, and source within the nursery. These findings suggest likely contamination hazards and target critical control points for management of Phytophthora disease using a systems approach. PMID:24702667

  15. Analyses and tests for design of an electro-impulse de-icing system

    NASA Technical Reports Server (NTRS)

    Zumwalt, G. W.; Schrag, R. L.; Bernhart, W. D.; Friedberg, R. A.

    1985-01-01

    De-icing of aircraft by using the electro-magnetic impulse phenomenon was proposed and demonstrated in several European countries. However, it is not available as a developed system due to lack of research on the basic physical mechanisms and necessary design parameters. The de-icing is accomplished by rapidly discharging high voltage capacitors into a wire coil rigidly supported just inside the aircraft skin. Induced eddy currents in the skin create a repulsive force resulting in a hammer-like force which cracks, de-bonds, and expels ice on the skin surface. The promised advantages are very low energy, high reliability of de-icing, and low maintenance. Three years of Electo-Impulse De-icing (EIDI) research is summarized and the analytical studies and results of testing done in the laboratory, in the NASA Icing Research Tunnel, and in flight are presented. If properly designed, EIDI was demonstrated to be an effective and practical ice protection system for small aircraft, turbojet engine inlets, elements of transport aircraft, and shows promise for use on helicopter rotor blades. Included are practical techniques of fabrication of impulse coils and their mountings. The use of EIDI with nonmetallic surface materials is also described.

  16. Static and dynamic analyses on the MFTF (Mirror Fusion Test Facility)-B Axicell Vacuum Vessel System: Final report

    SciTech Connect

    Ng, D.S.

    1986-09-01

    The Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) is a large-scale, tandem-mirror-fusion experiment. MFTF-B comprises many highly interconnected systems, including a magnet array and a vacuum vessel. The vessel, which houses the magnet array, is supported by reinforced concrete piers and steel frames resting on an array of foundations and surrounded by a 7-ft-thick concrete shielding vault. The Pittsburgh-Des Moines (PDM) Corporation, which was awarded the contract to design and construct the vessel, carried out fixed-base static and dynamic analyses of a finite-element model of the axicell vessel and magnet systems, including the simulation of various loading conditions and three postulated earthquake excitations. Meanwhile, LLNL monitored PDM's analyses with modeling studies of its own, and independently evaluated the structural responses of the vessel in order to define design criteria for the interface members and other project equipment. The assumptions underlying the finite-element model and the behavior of the axicell vessel are described in detail in this report, with particular emphasis placed on comparing the LLNL and PDM studies and on analyzing the fixed-base behavior with the soil-structure interaction, which occurs between the vessel and the massive concrete vault wall during a postulated seismic event. The structural members that proved sensitive to the soil effect are also reevaluated.

  17. Study of the ITER ICRH system with external matching by means of a mock-up loaded by a variable water load

    NASA Astrophysics Data System (ADS)

    Messiaen, A.; Vervier, M.; Dumortier, P.; Lamalle, P.; Louche, F.

    2006-07-01

    A mock-up of the complete antenna array (24 straps grouped in 8 triplets) of the ICRH system with external matching for ITER has been constructed with a length reduction factor of 5. At a frequency increased by the same factor the electrical properties of the full-scale system can be measured in the presence of non-dispersive medium. A movable water tank in front of the array simulates variable plasma loading. Measurements of the matching performances of various external circuit configurations and of the scattering matrix of the system show (i) the non-negligible effect of mutual coupling on load resilient matching by Conjugate T (CT) or hybrid leading to coupling between the matching actuators and the generators and asymmetry in power distribution, (ii) good load resilience of a single CT for the right choice of configuration and number of matching parameters, (iii) the large number of matching solutions for coupled CTs and (iv) the benefit of passive power distribution to the straps. This has been successfully tested in the case of the complete array. The power is passively distributed among the upper half and the bottom half of the 24 radiating straps of the antenna plug. The 4 top and 4 bottom triplets are, respectively, set in parallel outside the antenna plug near a voltage anti-node by means of T junctions. The load resilient matching (VSWR <1.3 for an antenna loading variation of about 1-8 ? m-1) is then obtained by a 4-parameters single CT configuration or a hybrid. The maximum voltage along the line remains equal to the one in the antenna plug and there is a fair power share between the straps. A straightforward robust matching procedure of the complete array is described. The effective radiation resistance of different toroidal and poloidal phasing conditions is measured and compared. The paper also underlines the significant influence of the presence of the electrostatic screen and the resulting increase in the recess of the straps on the reduction of the coupling to the load and of the mutual coupling between the straps.

  18. System Analyses of Pneumatic Technology for High Speed Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.; Tai, Jimmy C.; Kirby, Michelle M.; Roth, Bryce A.

    1999-01-01

    The primary aspiration of this study was to objectively assess the feasibility of the application of a low speed pneumatic technology, in particular Circulation Control (CC) to an HSCT concept. Circulation Control has been chosen as an enabling technology to be applied on a generic High Speed Civil Transport (HSCT). This technology has been proven for various subsonic vehicles including flight tests on a Navy A-6 and computational application on a Boeing 737. Yet, CC has not been widely accepted for general commercial fixed-wing use but its potential has been extensively investigated for decades in wind tunnels across the globe for application to rotorcraft. More recently, an experimental investigation was performed at Georgia Tech Research Institute (GTRI) with application to an HSCT-type configuration. The data from those experiments was to be applied to a full-scale vehicle to assess the impact from a system level point of view. Hence, this study attempted to quantitatively assess the impact of this technology to an HSCT. The study objective was achieved in three primary steps: 1) Defining the need for CC technology; 2) Wind tunnel data reduction; 3) Detailed takeoff/landing performance assessment. Defining the need for the CC technology application to an HSCT encompassed a preliminary system level analysis. This was accomplished through the utilization of recent developments in modern aircraft design theory at Aerospace Systems Design Laboratory (ASDL). These developments include the creation of techniques and methods needed for the identification of technical feasibility show stoppers. These techniques and methods allow the designer to rapidly assess a design space and disciplinary metric enhancements to enlarge or improve the design space. The takeoff and landing field lengths were identified as the concept "show-stoppers". Once the need for CC was established, the actual application of data and trends was assessed. This assessment entailed a reduction of the wind tunnel data from the experiments performed by Mr. Bob Englar at the GTRI. Relevant data was identified and manipulated based on the required format of the analysis tools utilized. Propulsive, aerodynamic, duct sizing, and vehicle sizing investigations were performed and information supplied to a detailed takeoff and landing tool, From the assessments, CC was shown to improve the low speed performance metrics, which were previously not satisfied. An HSCT with CC augmentation does show potential for full-scale application. Yet, an economic assessment of an HSCT with and without CC showed that a moderate penalty was incurred from the increased RDT&E costs associated with developing the CC technology and slight increases in empty weight.

  19. Analysis Methods and Desired Outcomes of System Interface Heat Transfer Fluid Requirements and Characteristics Analyses

    SciTech Connect

    Cliff B. Davis

    2005-04-01

    The interface between the Next Generation Nuclear Plant (NGNP) and the hydrogen-generating process plant will contain an intermediate loop that will transport heat from the NGNP to the process plant. Seven possible configurations for the NGNP primary coolant system and the intermediate heat transport loop were identified. Both helium and liquid salts are being considered as the working fluid in the intermediate heat transport loop. A method was developed to perform thermal-hydraulic evaluations of the different configurations and coolants. The evaluations will determine which configurations and coolants are the most promising from a thermal-hydraulic point of view and which, if any, do not appear to be feasible at the current time. Results of the evaluations will be presented in a subsequent report.

  20. CFD analyses of natural circulation in the air-cooled reactor cavity cooling system

    SciTech Connect

    Hu, R. [Nuclear Engineering Division, Argonne National Laboratory, Argonne IL (United States); Pointer, W. D. [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN (United States)

    2013-07-01

    The Natural Convection Shutdown Heat Removal Test Facility (NSTF) is currently being built at Argonne National Laboratory, to evaluate the feasibility of the passive Reactor Cavity Cooling System (RCCS) for Next Generation Nuclear Plant (NGNP). CFD simulations have been applied to evaluate the NSTF and NGNP RCCS designs. However, previous simulations found that convergence was very difficult to achieve in simulating the complex natural circulation. To resolve the convergence issue and increase the confidence of the CFD simulation results, additional CFD simulations were conducted using a more detailed mesh and a different solution scheme. It is found that, with the use of coupled flow and coupled energy models, the convergence can be greatly improved. Furthermore, the effects of convection in the cavity and the effects of the uncertainty in solid surface emissivity are also investigated. (authors)

  1. Melatonin, the circadian multioscillator system and health: the need for detailed analyses of peripheral melatonin signaling.

    PubMed

    Hardeland, Rüdiger; Madrid, Juan Antonio; Tan, Dun-Xian; Reiter, Russel J

    2012-03-01

    Evidence is accumulating regarding the importance of circadian core oscillators, several associated factors, and melatonin signaling in the maintenance of health. Dysfunction of endogenous clocks, melatonin receptor polymorphisms, age- and disease-associated declines of melatonin likely contribute to numerous diseases including cancer, metabolic syndrome, diabetes type 2, hypertension, and several mood and cognitive disorders. Consequences of gene silencing, overexpression, gene polymorphisms, and deviant expression levels in diseases are summarized. The circadian system is a complex network of central and peripheral oscillators, some of them being relatively independent of the pacemaker, the suprachiasmatic nucleus. Actions of melatonin on peripheral oscillators are poorly understood. Various lines of evidence indicate that these clocks are also influenced or phase-reset by melatonin. This includes phase differences of core oscillator gene expression under impaired melatonin signaling, effects of melatonin and melatonin receptor knockouts on oscillator mRNAs or proteins. Cross-connections between melatonin signaling pathways and oscillator proteins, including associated factors, are discussed in this review. The high complexity of the multioscillator system comprises alternate or parallel oscillators based on orthologs and paralogs of the core components and a high number of associated factors with varying tissue-specific importance, which offers numerous possibilities for interactions with melatonin. It is an aim of this review to stimulate research on melatonin signaling in peripheral tissues. This should not be restricted to primary signal molecules but rather include various secondarily connected pathways and discriminate between direct effects of the pineal indoleamine at the target organ and others mediated by modulation of oscillators. PMID:22034907

  2. Metagenome analyses of corroded concrete wastewater pipe biofilms reveal a complex microbial system

    PubMed Central

    2012-01-01

    Background Concrete corrosion of wastewater collection systems is a significant cause of deterioration and premature collapse. Failure to adequately address the deteriorating infrastructure networks threatens our environment, public health, and safety. Analysis of whole-metagenome pyrosequencing data and 16S rRNA gene clone libraries was used to determine microbial composition and functional genes associated with biomass harvested from crown (top) and invert (bottom) sections of a corroded wastewater pipe. Results Taxonomic and functional analysis demonstrated that approximately 90% of the total diversity was associated with the phyla Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria. The top (TP) and bottom pipe (BP) communities were different in composition, with some of the differences attributed to the abundance of sulfide-oxidizing and sulfate-reducing bacteria. Additionally, human fecal bacteria were more abundant in the BP communities. Among the functional categories, proteins involved in sulfur and nitrogen metabolism showed the most significant differences between biofilms. There was also an enrichment of genes associated with heavy metal resistance, virulence (protein secretion systems) and stress response in the TP biofilm, while a higher number of genes related to motility and chemotaxis were identified in the BP biofilm. Both biofilms contain a high number of genes associated with resistance to antibiotics and toxic compounds subsystems. Conclusions The function potential of wastewater biofilms was highly diverse with level of COG diversity similar to that described for soil. On the basis of the metagenomic data, some factors that may contribute to niche differentiation were pH, aerobic conditions and availability of substrate, such as nitrogen and sulfur. The results from this study will help us better understand the genetic network and functional capability of microbial members of wastewater concrete biofilms. PMID:22727216

  3. Spectrum transformation for divergent iterations

    NASA Technical Reports Server (NTRS)

    Gupta, Murli M.

    1991-01-01

    Certain spectrum transformation techniques are described that can be used to transform a diverging iteration into a converging one. Two techniques are considered called spectrum scaling and spectrum enveloping and how to obtain the optimum values of the transformation parameters is discussed. Numerical examples are given to show how this technique can be used to transform diverging iterations into converging ones; this technique can also be used to accelerate the convergence of otherwise convergent iterations.

  4. Requirements for ITER diagnostics

    SciTech Connect

    Young, K.M.

    1991-01-01

    The development and design of plasma diagnostics for the International Thermonuclear Experimental Reactor (ITER) present a formidable challenge for experimental plasma physicists. The large plasma size, the high central density and temperature and the very high thermal wall loadings provide new challenges for present measurement techniques and lead to a search for new methods. But the physics and control requirements for the long burn phase of the discharge, combined with very limited access to the plasma, constrained by the requirement for radiation shielding of the coils and sharing of access ports with heating and current drive power, remote manipulation, fueling and turn blanket modules, make for very difficult design choices. An initial attempt at these choices has been made by an international team of diagnostic physicists, gathering together in a series of three workshops during the ITER Conceptual Design Activity. This paper is based on that report and provides a summary of its most important points. To provide a background against which to place the diagnostic requirements and design concepts, the ITER device, its most important plasma properties and the proposed experimental program will be described. The specifications for the measurement of the plasma parameters and the proposed diagnostics for these measurements will then be addressed, followed by some examples of the design concepts that have been proposed. As a result of these design studies, it was clear that there were many uncertainties associated with these concepts, particularly because of the nuclear radiation environment, so that a Research and Development Program for diagnostic hardware was established. It will also be briefly summarized.

  5. 3D niche microarrays for systems-level analyses of cell fate

    PubMed Central

    Ranga, A.; Gobaa, S.; Okawa, Y.; Mosiewicz, K.; Negro, A.; Lutolf, M. P.

    2014-01-01

    The behaviour of mammalian cells in a tissue is governed by the three-dimensional (3D) microenvironment and involves a dynamic interplay between biochemical and mechanical signals provided by the extracellular matrix (ECM), cell–cell interactions and soluble factors. The complexity of the microenvironment and the context-dependent cell responses that arise from these interactions have posed a major challenge to understanding the underlying regulatory mechanisms. Here we develop an experimental paradigm to dissect the role of various interacting factors by simultaneously synthesizing more than 1,000 unique microenvironments with robotic nanolitre liquid-dispensing technology and by probing their effects on cell fate. Using this novel 3D microarray platform, we assess the combined effects of matrix elasticity, proteolytic degradability and three distinct classes of signalling proteins on mouse embryonic stem cells, unveiling a comprehensive map of interactions involved in regulating self-renewal. This approach is broadly applicable to gain a systems-level understanding of multifactorial 3D cell–matrix interactions. PMID:25027775

  6. Advanced computational analyses for design and control of pumped liquid loop systems

    NASA Astrophysics Data System (ADS)

    Furukawa, Masao

    Computational procedures are clearly shown in the tables in such a staged way that one may easily produce design calculations of cold plates, space radiators, and single-phase fluid loop systems. All the procedures are incorporated into a design code which can deal with two types of cold plates, five types of space radiators, and five configurations of a fluid loop mechanically driven by either rotodynamic or volumetric displacement. Equivalent hydraulic diameters, heat transfer area densities, dry weights, and pressure losses are calculated over a wide range of parameters to give demonstrative examples of design practices. For cold plate design optimization, the weight and the pressure loss are displayed in the figures as functions of baseplate area, width to length ratio, or diameter to diamter/height ratio. Several figures are then placed to understand the off-design heat absorption/rejection capability of a cold plate/flat radiator and to show the weight penalty of a curved radiator. An algorithm for flow modulation of a single loop and that of coupled two loops are constructed according to nine ways of cold plate temperature regulations. The algorithms are summarized in the tables on which another code is formulated. The required flow modulation rate versus the thermal load is shown in the figures as illustrative examples of loop control.

  7. Osiris: accessible and reproducible phylogenetic and phylogenomic analyses within the Galaxy workflow management system

    PubMed Central

    2014-01-01

    Background Phylogenetic tools and ‘tree-thinking’ approaches increasingly permeate all biological research. At the same time, phylogenetic data sets are expanding at breakneck pace, facilitated by increasingly economical sequencing technologies. Therefore, there is an urgent need for accessible, modular, and sharable tools for phylogenetic analysis. Results We developed a suite of wrappers for new and existing phylogenetics tools for the Galaxy workflow management system that we call Osiris. Osiris and Galaxy provide a sharable, standardized, modular user interface, and the ability to easily create complex workflows using a graphical interface. Osiris enables all aspects of phylogenetic analysis within Galaxy, including de novo assembly of high throughput sequencing reads, ortholog identification, multiple sequence alignment, concatenation, phylogenetic tree estimation, and post-tree comparative analysis. The open source files are available on in the Bitbucket public repository and many of the tools are demonstrated on a public web server (http://galaxy-dev.cnsi.ucsb.edu/osiris/). Conclusions Osiris can serve as a foundation for other phylogenomic and phylogenetic tool development within the Galaxy platform. PMID:24990571

  8. Design and analysis of iteratively decodable codes for ISI channels

    E-print Network

    Doan, Dung Ngoc

    2005-11-01

    Recent advancements in iterative processing have allowed communication systems to perform close to capacity limits withmanageable complexity.For manychannels such as the AWGN and ?at fading channels, codes that perform only a fraction of a d...

  9. Plans for U.S. Contributions to ITER

    E-print Network

    Physics Laboratory (New Jersey) · Electric Power Systems · Diagnostics Savannah River National Laboratory, but co-located U.S. ITER / Sauthoff Slide 4 #12;Oak Ridge National Laboratory (Tennessee), host lab

  10. Systems Analyses of Advanced Brayton Cycles For High Efficiency Zero Emission Plants

    SciTech Connect

    A. D. Rao; J. Francuz; H. Liao; A. Verma; G. S. Samuelsen

    2006-11-01

    Table 1 shows that the systems efficiency, coal (HHV) to power, is 35%. Table 2 summarizes the auxiliary power consumption within the plant. Thermoflex was used to simulate the power block and Aspen Plus the balance of plant. The overall block flow diagram is presented in Figure A1.3-1 and the key unit process flow diagrams are shown in subsequent figures. Stream data are given in Table A1.3-1. Equipment function specifications are provided in Tables A1.3-2 through 17. The overall plant scheme consists of a cryogenic air separation unit supplying 95% purity O{sub 2} to GE type high pressure (HP) total quench gasifiers. The raw gas after scrubbing is treated in a sour shift unit to react the CO with H{sub 2}O to form H{sub 2} and CO{sub 2}. The gas is further treated to remove Hg in a sulfided activated carbon bed. The syngas is desulfurized and decarbonized in a Selexol acid gas removal unit and the decarbonized syngas after humidification and preheat is fired in GE 7H type steam cooled gas turbines. Intermediate pressure (IP) N{sub 2} from the ASU is also supplied to the combustors of the gas turbines as additional diluent for NOx control. A portion of the air required by the ASU is extracted from the gas turbines. The plant consists of the following major process units: (1) Air Separation Unit (ASU); (2) Gasification Unit; (3) CO Shift/Low Temperature Gas Cooling (LTGC) Unit; (4) Acid Gas Removal Unit (AGR) Unit; (5) Fuel Gas Humidification Unit; (6) Carbon Dioxide Compression/Dehydration Unit; (7) Claus Sulfur Recovery/Tail Gas Treating Unit (SRU/TGTU); and (8) Power Block.

  11. Error analyses of JEM/SMILES standard products on L2 operational system

    NASA Astrophysics Data System (ADS)

    Mitsuda, C.; Takahashi, C.; Suzuki, M.; Hayashi, H.; Imai, K.; Sano, T.; Takayanagi, M.; Iwata, Y.; Taniguchi, H.

    2009-12-01

    SMILES (Superconducting Submillimeter-wave Limb-Emission Sounder) , which has been developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT), is planned to be launched in September, 2009 and will be on board the Japanese Experiment Module (JEM) of the International Space Station (ISS). The SMILES measures the atmospheric limb emission from stratospheric minor constituents in 640 GHz band. Target species on L2 operational system are O3, ClO, HCl, HNO3, HOCl, CH3CN, HO2, BrO, and O3 isotopes (18OOO, 17OOO and O17OO). The SMILES carries 4 K cooled Superconductor-Insulator-Superconductor mixers to carry out high-sensitivity observations. In sub-millimeter band, water vapor absorption is an important factor to decide the tropospheric and stratospheric brightness temperature. The uncertainty of water vapor absorption influences the accuracy of molecular vertical profiles. Since the SMILES bands are narrow and far from H2O lines, it is a good approximation to assume this uncertainly as linear function of frequency. We include 0th and 1st coefficients of ‘baseline’ function, not water vapor profile, in state vector and retrieve them to remove influence of the water vapor uncertainty. We performed retrieval simulations using spectra computed by L2 operatinal forward model for various H2O conditions (-/+ 5, 10% difference between true profile and a priori profile in the stratosphere and -/+ 10, 20% one in the troposphere). The results show that the incremental errors of molecules are smaller than 10% of measurements errors when height correlation of baseline coefficients and temperature are assumed to be 10 km. In conclusion, the retrieval of the baseline coefficients effectively suppresses profile error due to bias of water vapor profile.

  12. Quantitative and functional analyses of spastin in the nervous system: implications for hereditary spastic paraplegia.

    PubMed

    Solowska, Joanna M; Morfini, Gerardo; Falnikar, Aditi; Himes, B Timothy; Brady, Scott T; Huang, Dongyang; Baas, Peter W

    2008-02-27

    Spastin and P60-katanin are two distinct microtubule-severing proteins. Autosomal dominant mutations in the SPG4 locus corresponding to spastin are the most common cause of hereditary spastic paraplegia (HSP), a neurodegenerative disease that afflicts the adult corticospinal tracts. Here we sought to evaluate whether SPG4-based HSP is best understood as a "loss-of-function" disease. Using various rat tissues, we found that P60-katanin levels are much higher than spastin levels during development. In the adult, P60-katanin levels plunge dramatically but spastin levels decline only slightly. Quantitative data of spastin expression in specific regions of the nervous system failed to reveal any obvious explanation for the selective sensitivity of adult corticospinal tracts to loss of spastin activity. An alternative explanation relates to the fact that the mammalian spastin gene has two start codons, resulting in a 616 amino acid protein called M1 and a slightly shorter protein called M85. We found that M1 is almost absent from developing neurons and most adult neurons but comprises 20-25% of the spastin in the adult spinal cord, the location of the axons that degenerate during HSP. Experimental expression in cultured neurons of a short dysfunctional M1 polypeptide (but not a short dysfunctional M85 peptide) is deleterious to normal axonal growth. In squid axoplasm, the M1 peptide dramatically inhibits fast axonal transport, whereas the M85 peptide does not. These results are consistent with a "gain-of-function" mechanism underlying HSP wherein spastin mutations produce a cytotoxic protein in the case of M1 but not M85. PMID:18305248

  13. Uncovering the Dynamics of Cardiac Systems Using Stochastic Pacing and Frequency Domain Analyses

    PubMed Central

    Lemay, Mathieu; de Lange, Enno; Kucera, Jan P.

    2012-01-01

    Alternans of cardiac action potential duration (APD) is a well-known arrhythmogenic mechanism which results from dynamical instabilities. The propensity to alternans is classically investigated by examining APD restitution and by deriving APD restitution slopes as predictive markers. However, experiments have shown that such markers are not always accurate for the prediction of alternans. Using a mathematical ventricular cell model known to exhibit unstable dynamics of both membrane potential and Ca2+ cycling, we demonstrate that an accurate marker can be obtained by pacing at cycle lengths (CLs) varying randomly around a basic CL (BCL) and by evaluating the transfer function between the time series of CLs and APDs using an autoregressive-moving-average (ARMA) model. The first pole of this transfer function corresponds to the eigenvalue (?alt) of the dominant eigenmode of the cardiac system, which predicts that alternans occurs when ?alt??1. For different BCLs, control values of ?alt were obtained using eigenmode analysis and compared to the first pole of the transfer function estimated using ARMA model fitting in simulations of random pacing protocols. In all versions of the cell model, this pole provided an accurate estimation of ?alt. Furthermore, during slow ramp decreases of BCL or simulated drug application, this approach predicted the onset of alternans by extrapolating the time course of the estimated ?alt. In conclusion, stochastic pacing and ARMA model identification represents a novel approach to predict alternans without making any assumptions about its ionic mechanisms. It should therefore be applicable experimentally for any type of myocardial cell. PMID:22396631

  14. A high-resolution photon-counting breast CT system with tensor-framelet based iterative image reconstruction for radiation dose reduction.

    PubMed

    Ding, Huanjun; Gao, Hao; Zhao, Bo; Cho, Hyo-Min; Molloi, Sabee

    2014-10-21

    Both computer simulations and experimental phantom studies were carried out to investigate the radiation dose reduction with tensor framelet based iterative image reconstruction (TFIR) for a dedicated high-resolution spectral breast computed tomography (CT) based on a silicon strip photon-counting detector. The simulation was performed with a 10?cm-diameter water phantom including three contrast materials (polyethylene, 8?mg?ml(-1) iodine and B-100 bone-equivalent plastic). In the experimental study, the data were acquired with a 1.3?cm-diameter polymethylmethacrylate (PMMA) phantom containing iodine in three concentrations (8, 16 and 32?mg?ml(-1)) at various radiation doses (1.2, 2.4 and 3.6?mGy) and then CT images were reconstructed using the filtered-back-projection (FBP) technique and the TFIR technique, respectively. The image quality between these two techniques was evaluated by the quantitative analysis on contrast-to-noise ratio (CNR) and spatial resolution that was evaluated using the task-based modulation transfer function (MTF). Both the simulation and experimental results indicated that the task-based MTF obtained from TFIR reconstruction with one-third of the radiation dose was comparable to that from the FBP reconstruction for low contrast target. For high contrast target, the TFIR was substantially superior to the FBP reconstruction in terms of spatial resolution. In addition, TFIR was able to achieve a factor of 1.6-1.8 increase in CNR, depending on the target contrast level. This study demonstrates that the TFIR can reduce the required radiation dose by a factor of two-thirds for a CT image reconstruction compared to the FBP technique. It achieves much better CNR and spatial resolution for high contrast target in addition to retaining similar spatial resolution for low contrast target. This TFIR technique has been implemented with a graphic processing unit system and it takes approximately 10?s to reconstruct a single-slice CT image, which can potentially be used in a future multi-slit multi-slice spiral CT system. PMID:25230204

  15. A high-resolution photon-counting breast CT system with tensor-framelet based iterative image reconstruction for radiation dose reduction

    NASA Astrophysics Data System (ADS)

    Ding, Huanjun; Gao, Hao; Zhao, Bo; Cho, Hyo-Min; Molloi, Sabee

    2014-10-01

    Both computer simulations and experimental phantom studies were carried out to investigate the radiation dose reduction with tensor framelet based iterative image reconstruction (TFIR) for a dedicated high-resolution spectral breast computed tomography (CT) based on a silicon strip photon-counting detector. The simulation was performed with a 10?cm-diameter water phantom including three contrast materials (polyethylene, 8?mg?ml?1 iodine and B-100 bone-equivalent plastic). In the experimental study, the data were acquired with a 1.3?cm-diameter polymethylmethacrylate (PMMA) phantom containing iodine in three concentrations (8, 16 and 32?mg?ml?1) at various radiation doses (1.2, 2.4 and 3.6?mGy) and then CT images were reconstructed using the filtered-back-projection (FBP) technique and the TFIR technique, respectively. The image quality between these two techniques was evaluated by the quantitative analysis on contrast-to-noise ratio (CNR) and spatial resolution that was evaluated using the task-based modulation transfer function (MTF). Both the simulation and experimental results indicated that the task-based MTF obtained from TFIR reconstruction with one-third of the radiation dose was comparable to that from the FBP reconstruction for low contrast target. For high contrast target, the TFIR was substantially superior to the FBP reconstruction in terms of spatial resolution. In addition, TFIR was able to achieve a factor of 1.6–1.8 increase in CNR, depending on the target contrast level. This study demonstrates that the TFIR can reduce the required radiation dose by a factor of two-thirds for a CT image reconstruction compared to the FBP technique. It achieves much better CNR and spatial resolution for high contrast target in addition to retaining similar spatial resolution for low contrast target. This TFIR technique has been implemented with a graphic processing unit system and it takes approximately 10?s to reconstruct a single-slice CT image, which can potentially be used in a future multi-slit multi-slice spiral CT system.

  16. ITER (International Thermonuclear Experimental Reactor) current drive and heating physics

    SciTech Connect

    Nevins, W.M.; Lindquist, W. (Lawrence Livermore National Lab., CA (USA)); Fujisawa, N.; Kimura, H. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)); Hopman, H.; Rebuffi, L.; Wegrowe, J.G. (Max-Planck-Institut fuer Plasmaphysik, Garching (Germany, F.R.). NET Design Team); Parail, V.; Vdovin, V. (Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Moscow (USSR). Inst. Atomnoj Ehn

    1990-01-01

    The ITER Current Drive and Heating (CD H) systems are required for: Ionization and current initiation; Non-inductive current ramp-up assist; Heating of the plasma; Steady-state operation with full non-inductive current drive; Current profile control; and Burn control by modulation of the auxiliary power. Steady-state current drive is the most demanding requirement, so this has driven the choice of the ITER current drive and heating systems.

  17. Structural Conditions for Collaboration and Learning in Innovation Networks: Using an Innovation System Performance Lens to Analyse Agricultural Knowledge Systems

    ERIC Educational Resources Information Center

    Hermans, Frans; Klerkx, Laurens; Roep, Dirk

    2015-01-01

    Purpose: We investigate how the structural conditions of eight different European agricultural innovation systems can facilitate or hinder collaboration and social learning in multidisciplinary innovation networks. Methodology: We have adapted the Innovation System Failure Matrix to investigate the main barriers and enablers eight countries…

  18. Attributes of mesoscale convective systems at the land-ocean transition in Senegal during NASA African Monsoon Multidisciplinary Analyses 2006

    NASA Astrophysics Data System (ADS)

    Delonge, Marcia S.; Fuentes, Jose D.; Chan, Stephen; Kucera, Paul A.; Joseph, Everette; Gaye, Amadou T.; Daouda, Badiane

    2010-05-01

    In this study we investigate the development of a mesoscale convective system (MCS) as it moved from West Africa to the Atlantic Ocean on 31 August 2006. We document surface and atmospheric conditions preceding and following the MCS, particularly near the coast. These analyses are used to evaluate how thermodynamic and microphysical gradients influence storms as they move from continental to maritime environments. To achieve these goals, we employ observations from NASA African Monsoon Multidisciplinary Analyses (NAMMA) from the NASA S band polarimetric Doppler radar, a meteorological flux tower, upper-air soundings, and rain gauges. We show that the MCS maintained a convective leading edge and trailing stratiform region as it propagated from land to ocean. The initial strength and organization of the MCS were associated with favorable antecedent conditions in the continental lower atmosphere, including high specific humidity (18 g kg-1), temperatures (300 K), and wind shear. While transitioning, the convective and stratiform regions became weaker and disorganized. Such storm changes were linked to less favorable thermodynamic, dynamic, and microphysical conditions over ocean. To address whether storms in different life-cycle phases exhibited similar features, a composite analysis of major NAMMA events was performed. This analysis revealed an even stronger shift to lower reflectivity values over ocean. These findings support the hypothesis that favorable thermodynamic conditions over the coast are a prerequisite to ensuring that MCSs do not dissipate at the continental-maritime transition, particularly due to strong gradients that can weaken West African storms moving from land to ocean.

  19. Towards plasma cleaning of ITER first mirrors

    NASA Astrophysics Data System (ADS)

    Moser, L.; Marot, L.; Eren, B.; Steiner, R.; Mathys, D.; Leipold, F.; Reichle, R.; Meyer, E.

    2015-06-01

    To avoid reflectivity losses in ITER's optical diagnostic systems, on-site cleaning of metallic first mirrors via plasma sputtering is foreseen to remove deposit build-ups migrating from the main wall. In this work, the influence of aluminium and tungsten deposits on the reflectivity of molybdenum mirrors as well as the possibility to clean them with plasma exposure is investigated. Porous ITER-like deposits are grown to mimic the edge conditions expected in ITER, and a severe degradation in the specular reflectivity is observed as these deposits build up on the mirror surface. In addition, dense oxide films are produced for comparisons with porous films. The composition, morphology and crystal structure of several films were characterized by means of scanning electron microscopy, x-ray photoelectron spectroscopy, x-ray diffraction and secondary ion mass spectrometry. The cleaning of the deposits and the restoration of the mirrors' optical properties are possible either with a Kaufman source or radio frequency directly applied to the mirror (or radio frequency plasma generated directly around the mirror surface). Accelerating ions of an external plasma source through a direct current applied onto the mirror does not remove deposits composed of oxides. A possible implementation of plasma cleaning in ITER is addressed.

  20. Large Deployable Reflector (LDR) system concept and technology definition study. Volume 1: Executive summary, analyses and trades, and system concepts

    NASA Technical Reports Server (NTRS)

    Agnew, Donald L.; Jones, Peter A.

    1989-01-01

    A study was conducted to define reasonable and representative large deployable reflector (LDR) system concepts for the purpose of defining a technology development program aimed at providing the requisite technological capability necessary to start LDR development by the end of 1991. This volume includes the executive summary for the total study, a report of thirteen system analysis and trades tasks (optical configuration, aperture size, reflector material, segmented mirror, optical subsystem, thermal, pointing and control, transportation to orbit, structures, contamination control, orbital parameters, orbital environment, and spacecraft functions), and descriptions of three selected LDR system concepts. Supporting information is contained in appendices.

  1. A preliminary engineering assessment of the ITER CDA ECH launcher

    SciTech Connect

    Bigelow, T.S.; Swain, D.W. [Oak Ridge National Lab., TN (US); Sawan, M. [Univ. of Wisconsin, Madison, WI (US)

    1993-06-01

    A preliminary engineering study of the ITER electron cyclotron heating (ECH) launcher configuration proposed by the ITER Conceptual Design Activity (CDA) team has been performed to assess its survivability in the ITER nuclear environment. Potential problem areas are with the vacuum windows, the plasma-facing mirrors, and some of the other high-power waveguide components that are untested in a reactor environment. The study indicates that the CDA design is quite robust, since the mirror power density is relatively low and the windows are well shielded. Although the CDA ECH system is unlikely to be built as proposed, most analysis techniques developed to study this system will apply to future ITER ECH system configurations. The vacuum window is likely to be the most difficult launcher component to develop. Design for a proposed resonant ring for high-power testing of windows using existing lower-power gyrotrons is presented.

  2. Sociopolitical Analyses.

    ERIC Educational Resources Information Center

    Van Galen, Jane, Ed.; And Others

    1992-01-01

    This theme issue of the serial "Educational Foundations" contains four articles devoted to the topic of "Sociopolitical Analyses." In "An Interview with Peter L. McLaren," Mary Leach presented the views of Peter L. McLaren on topics of local and national discourses, values, and the politics of difference. Landon E. Beyer's "Educational Studies and…

  3. Krylov iterative methods and synthetic acceleration for transport in binary statistical media

    SciTech Connect

    Fichtl, Erin D. [Computational Physics and Methods, Los Alamos National Laboratory, Los Alamos, NM 87545-0001 (United States)], E-mail: efichtl@lanl.gov; Warsa, James S. [Computational Physics and Methods, Los Alamos National Laboratory, Los Alamos, NM 87545-0001 (United States)], E-mail: warsa@lanl.gov; Prinja, Anil K. [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, NM 87131-1341 (United States)], E-mail: prinja@unm.edu

    2009-12-01

    In particle transport applications there are numerous physical constructs in which heterogeneities are randomly distributed. The quantity of interest in these problems is the ensemble average of the flux, or the average of the flux over all possible material 'realizations.' The Levermore-Pomraning closure assumes Markovian mixing statistics and allows a closed, coupled system of equations to be written for the ensemble averages of the flux in each material. Generally, binary statistical mixtures are considered in which there are two (homogeneous) materials and corresponding coupled equations. The solution process is iterative, but convergence may be slow as either or both materials approach the diffusion and/or atomic mix limits. A three-part acceleration scheme is devised to expedite convergence, particularly in the atomic mix-diffusion limit where computation is extremely slow. The iteration is first divided into a series of 'inner' material and source iterations to attenuate the diffusion and atomic mix error modes separately. Secondly, atomic mix synthetic acceleration is applied to the inner material iteration and S{sub 2} synthetic acceleration to the inner source iterations to offset the cost of doing several inner iterations per outer iteration. Finally, a Krylov iterative solver is wrapped around each iteration, inner and outer, to further expedite convergence. A spectral analysis is conducted and iteration counts and computing cost for the new two-step scheme are compared against those for a simple one-step iteration, to which a Krylov iterative method can also be applied.

  4. Krylov iterative methods and synthetic acceleration for transport in binary statistical media

    SciTech Connect

    Fichtl, Erin D [Los Alamos National Laboratory; Warsa, James S [Los Alamos National Laboratory; Prinja, Anil K [Los Alamos National Laboratory

    2008-01-01

    In particle transport applications there are numerous physical constructs in which heterogeneities are randomly distributed. The quantity of interest in these problems is the ensemble average of the flux, or the average of the flux over all possible material 'realizations.' The Levermore-Pomraning closure assumes Markovian mixing statistics and allows a closed, coupled system of equations to be written for the ensemble averages of the flux in each material. Generally, binary statistical mixtures are considered in which there are two (homogeneous) materials and corresponding coupled equations. The solution process is iterative, but convergence may be slow as either or both materials approach the diffusion and/or atomic mix limits. A three-part acceleration scheme is devised to expedite convergence, particularly in the atomic mix-diffusion limit where computation is extremely slow. The iteration is first divided into a series of 'inner' material and source iterations to attenuate the diffusion and atomic mix error modes separately. Secondly, atomic mix synthetic acceleration is applied to the inner material iteration and S{sup 2} synthetic acceleration to the inner source iterations to offset the cost of doing several inner iterations per outer iteration. Finally, a Krylov iterative solver is wrapped around each iteration, inner and outer, to further expedite convergence. A spectral analysis is conducted and iteration counts and computing cost for the new two-step scheme are compared against those for a simple one-step iteration, to which a Krylov iterative method can also be applied.

  5. US ITER Project Providing a Facility for

    E-print Network

    US ITER Project Providing a Facility for Burning Plasma Research Ned Sauthoff Project Manager, US to position the US for Burning Plasma Research #12;U.S. ITER / Sauthoff Slide 2 Structure of the Talk... ITER

  6. Mathematical Iteration through Computer Programming.

    ERIC Educational Resources Information Center

    Prichard, Mary Kim

    1993-01-01

    Discusses the process of mathematical iteration, its benefits as a problem-solving technique, and how to teach it. Presents a selection of mathematical ideas and problems that can be solved and explored using iteration, along with related BASIC computer programs. (MDH)

  7. Microbeam Analyses of Rare-Earth Element (REE) and Sr Isotopes of Anhydrite Veins From the PACMANUS Hydrothermal System

    NASA Astrophysics Data System (ADS)

    Craddock, P. R.; Bach, W.

    2004-12-01

    Ocean Drilling Program Leg 193 drilled into areas of focused and diffuse venting from the PACMANUS hydrothermal field along Pual Ridge, eastern Manus Basin. Pual Ridge is primarily composed of fresh dacite that is pervasively altered to argillaceous (illite-chlorite) and overprinting acid-sulfate (pyrophyllite-anhydrite) and siliceous secondary mineral assemblages. Anhydrite is an abundant precipitate in all cores recovered beneath the active vent field. Isotopic (Sr, S), elemental (Mg, Sr, REE) and fluid inclusion analyses on anhydrite mineral separates demonstrate that pathways of fluid evolution (magmatic input, variable fluid composition, seawater entrainment) differ on the meter scale within this system. In addition, large variations in REE content, S (? 34S > 5‰ ) and Sr (87Sr/86Sr > 1000 ppm) isotope composition are observed within individual anhydrite veins. Using microbeam techniques, we have analyzed this small scale chemical and isotopic heterogeneity in order to unravel the record of hydrothermal processes occurring at PACMANUS. Cathodoluminescence microscopy is used to distinguish between different crystal growth textures (e.g., oscillatory versus sector zoning). A Finnigan Neptune laser-ablation MC-ICP-MS is used to measure 87Sr/86Sr, and a Cameca 3f ion microprobe and a Finnigan Element2 laser-ablation MC-ICP-MS to measure REE and minor element concentrations in these zones. Initial microbeam measurements of sector-zoned crystals reveal REE patterns trending from mid-REE enriched to MREE depleted with distance from crystal center and with a uniform 87Sr/86Sr (0.7087). Analyses for oscillatory zoned crystals reveal variable and increasing 87Sr/86Sr (0.7043 to 0.7089) and REE patterns trending from light-REE enriched to LREE depleted with both negative and positive Eu anomalies during crystal growth. 87Sr/86Sr reproducibility for an isotopically homogenous anhydrite is better than 40 ppm. The Sr isotopic composition range for heterogenous crystals (> 4000 ppm) is hence greater than 100 times the analytical uncertainty of our LA-MC-ICP-MS method. The general trend of these data can be modeled by Rayleigh-type fractional crystallization of anhydrite, with sector zoned anhydrite precipitating from a seawater dominated fluid and oscillatory zoned anhydrite forming from a hydrothermally dominated fluid following introduction of seawater into the basement. Future microbeam REE, Sr and S-isotope analyses are planned to provide a more comprehensive view of fluid evolution and mineral formation within this backarc hydrothermal system.

  8. The detective quantum efficiency of photon-counting x-ray detectors using cascaded-systems analyses

    SciTech Connect

    Tanguay, Jesse [Robarts Research Institute and Department of Medical Biophysics, Western University, London, Ontario N6A 5C1 (Canada); Yun, Seungman [Biomedical Engineering Program, Western University, London, Ontario N6A 5C1 (Canada); School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Kim, Ho Kyung [School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Cunningham, Ian A. [Robarts Research Institute, Department of Medical Biophysics, and Biomedical Engineering Program, Western University, London, Ontario N6A 5C1 (Canada)

    2013-04-15

    Purpose: Single-photon counting (SPC) x-ray imaging has the potential to improve image quality and enable new advanced energy-dependent methods. The purpose of this study is to extend cascaded-systems analyses (CSA) to the description of image quality and the detective quantum efficiency (DQE) of SPC systems. Methods: Point-process theory is used to develop a method of propagating the mean signal and Wiener noise-power spectrum through a thresholding stage (required to identify x-ray interaction events). The new transfer relationships are used to describe the zero-frequency DQE of a hypothetical SPC detector including the effects of stochastic conversion of incident photons to secondary quanta, secondary quantum sinks, additive noise, and threshold level. Theoretical results are compared with Monte Carlo calculations assuming the same detector model. Results: Under certain conditions, the CSA approach can be applied to SPC systems with the additional requirement of propagating the probability density function describing the total number of image-forming quanta through each stage of a cascaded model. Theoretical results including DQE show excellent agreement with Monte Carlo calculations under all conditions considered. Conclusions: Application of the CSA method shows that false counts due to additive electronic noise results in both a nonlinear image signal and increased image noise. There is a window of allowable threshold values to achieve a high DQE that depends on conversion gain, secondary quantum sinks, and additive noise.

  9. Validation of the sperm class analyser CASA system for sperm counting in a busy diagnostic semen analysis laboratory.

    PubMed

    Dearing, Chey G; Kilburn, Sally; Lindsay, Kevin S

    2014-03-01

    Sperm counts have been linked to several fertility outcomes making them an essential parameter of semen analysis. It has become increasingly recognised that Computer-Assisted Semen Analysis (CASA) provides improved precision over manual methods but that systems are seldom validated robustly for use. The objective of this study was to gather the evidence to validate or reject the Sperm Class Analyser (SCA) as a tool for routine sperm counting in a busy laboratory setting. The criteria examined were comparison with the Improved Neubauer and Leja 20-?m chambers, within and between field precision, sperm concentration linearity from a stock diluted in semen and media, accuracy against internal and external quality material, assessment of uneven flow effects and a receiver operating characteristic (ROC) analysis to predict fertility in comparison with the Neubauer method. This work demonstrates that SCA CASA technology is not a standalone 'black box', but rather a tool for well-trained staff that allows rapid, high-number sperm counting providing errors are identified and corrected. The system will produce accurate, linear, precise results, with less analytical variance than manual methods that correlate well against the Improved Neubauer chamber. The system provides superior predictive potential for diagnosing fertility problems. PMID:24359435

  10. Rapid analyses of proteomes and interactomes using an integrated solid-phase extraction-liquid chromatography-MS/MS system.

    PubMed

    Binai, Nadine A; Marino, Fabio; Soendergaard, Peter; Bache, Nicolai; Mohammed, Shabaz; Heck, Albert J R

    2015-02-01

    Here, we explore applications of a LC system using disposable solid-phase extraction (SPE) cartridges and very short LC-MS/MS gradients that allows for rapid analyses in less than 10 min analysis time. The setup consists of an autosampler harboring two sets of 96 STAGE tips that function as precolumns and a short RP analytical column running 6.5 min gradients. This system combines efficiently with several proteomics workflows such as offline prefractionation methods, including 1D gel electrophoresis and strong-cation exchange chromatography. It also enables the analysis of interactomes obtained by affinity purification with an analysis time of approximately 1 h. In a typical shotgun proteomics experiment involving 36 SCX fractions of an AspN digested cell lysate, we detected over 3600 protein groups with an analysis time of less than 5.5 h. This innovative fast LC system reduces proteome analysis time while maintaining sufficient proteomic detail. This has particular relevance for the use of proteomics within a clinical environment, where large sample numbers and fast turnover times are essential. PMID:25485597

  11. Satellite power system (SPS) concept definition study (Exhibit D). Volume 2: systems\\/subsystems analyses. Final report

    Microsoft Academic Search

    1981-01-01

    Modifications to the reference concept were studied and the best approaches defined. The impact of the high efficiency multibandgap solar array on the reference concept design is considered. System trade studies for several solid state concepts, including the sandwich concept and a separate antenna\\/solar concept, are described. Two solid state concepts were selected and a design definition is presented for

  12. Iterated crowdsourcing dilemma game

    PubMed Central

    Oishi, Koji; Cebrian, Manuel; Abeliuk, Andres; Masuda, Naoki

    2014-01-01

    The Internet has enabled the emergence of collective problem solving, also known as crowdsourcing, as a viable option for solving complex tasks. However, the openness of crowdsourcing presents a challenge because solutions obtained by it can be sabotaged, stolen, and manipulated at a low cost for the attacker. We extend a previously proposed crowdsourcing dilemma game to an iterated game to address this question. We enumerate pure evolutionarily stable strategies within the class of so-called reactive strategies, i.e., those depending on the last action of the opponent. Among the 4096 possible reactive strategies, we find 16 strategies each of which is stable in some parameter regions. Repeated encounters of the players can improve social welfare when the damage inflicted by an attack and the cost of attack are both small. Under the current framework, repeated interactions do not really ameliorate the crowdsourcing dilemma in a majority of the parameter space. PMID:24526244

  13. Precursor systems analyses of automated highway systems. Activity area K AHS roadway operational analysis. Final report, September 1993-November 1994

    SciTech Connect

    Schulze, R.; Roper, D.; Tsao, J.; Michael, B.

    1995-05-01

    This study considers the roadway operational requirements of an automated highway system (AHS) in light of corresponding operational requirements for existing conventional highways with traffic operations centers (TOCs). Contrasts and similarities between TOC and AHS operations are identified. Maintenance operations and activities are the focus of the study. Similarities and contrasts between AHS and conventional highways are considered, analyzed, and discussed to raise issues risks. Urban/rural, passenger/heavy vehicle, and representative system configuration differences are covered insofar as there are significant differences among these categories of possible AHS operations. Maintenance needs and incident response requirements as they would impact as AHS operating agency are qualitatively analyzed. Two possible staged deployment scenarios for AHS are presented. The fault tolerance of the AHS is assessed. Results of interviews with personnel in charge of several existing TOCs have been summarized. The role of the driver in an AHS is discussed.

  14. Variance analyses from invariance analyses

    Microsoft Academic Search

    Josh Berdine; Aziem Chawdhary; Byron Cook; Dino Distefano; Peter W. O'hearn

    2007-01-01

    An invariance assertion for a program location ' is a statement that always holds at ' during execution of the program. Program invari- ance analyses infer invariance assertions that can be useful when trying to prove safety properties. We use the term variance asser- tion to mean a statement that holds between any state at ' and any previous state

  15. Application of time-series analyses to the hydrological functioning of an Alpine karstic system: the case of Bange-L'Eau-Morte

    NASA Astrophysics Data System (ADS)

    Mathevet, T.; Lepiller, M. L.; Mangin, A.

    This paper analyses the hydrological functioning of the Bange-L’Eau-Morte karstic system using classical and original techniques, recession curves, correlation and spectral analyses, noise analysis and wavelet analyses. The main characteristics that can be deduced are the recession coefficients, the dynamic volume of storage, the response time of the system, the quickflow and baseflow components and the snowmelt characteristics. The non-stationary and timescale-dependent behaviour of the system is studied and particular features of the runoff are shown. The step-by-step use of these different techniques provides a general methodology applicable to different karstic systems to provide quantifiable and objective criteria for differentiation and comparison of karstic systems.

  16. Sensitivity of Middle Atmospheric Analyses to the Representation of Gravity-Wave Drag in the DAO's Data Assimilation System

    NASA Technical Reports Server (NTRS)

    Li, Shuhua; Chern, Jiundar; Joiner, Joanna; Lin, Shian-Jiann; Pawson, Steven; daSilva, Arlindo; Atlas, Robert (Technical Monitor)

    2002-01-01

    The damping of mesoscale gravity waves has important effects on the global circulation, structure, and composition of the atmosphere. A number of assimilation and forecast experiments have been conducted to examine the sensitivity of meteorological analyses and forecasts to the representation of gravity wave impacts in a data assimilation system (DAS). The experiments were conducted with the Finite-Volume (FV) DAS developed at NASA's Data Assimilation Office (DAO), The main purpose of this research is to determine the optimal combination of wave number, phase speed, wavelength, etc. for representing gravity-wave drag (GWD) in FVDAS. The GWD included in FVDAS includes a spectrum of waves, as would be forced by topography and transient motions (e.g., convection) in the troposphere. The sensitivity experiments are performed by modifying several parameters, such as the number of waves allowed, their wavelength, the background stress amplitude, etc. The results show that the assimilated fields are very sensitive to the number of gravity waves represented in the system, especially at high latitudes of the middle and upper stratosphere and mesosphere in winter. The analyzed stratopause temperature varies by up to 10K when the GWD scheme is modified from a multiple-wave scheme (using a stationary wave and waves with phase speeds of 10, 20, 30 and 40 m/s in each direction) to a single, stationary wave. Insight into the reality of the various versions of the GWD can be obtained by examining the "Observation minus Forecast" residuals from the FVDAS.

  17. Analyses and comparison of an energy harvesting system for dielectric elastomer generators using a passive harvesting concept: the voltage-clamped multi-phase system

    NASA Astrophysics Data System (ADS)

    van Kessel, Rick; Wattez, Ambroise; Bauer, Pavol

    2015-04-01

    This work investigates a passive Dielectric Elastomer Generator harvesting system which uses only diodes at the generator level. The resulting voltage-clamped topology is presented and its operating principles are explained. Analytical analyses using charge-voltage diagrams form the basis for quantifying the energy output and optimizing the bus voltages. It is shown that for most cycles the energy output tends to be lower compared to active harvesting systems with dedicated converters for each generator, yet the maturity and simplicity make it a preferred solution for short-term deployment. An outlook towards industrialization applied to SBM Offshore's S3 Wave Energy Converter highlights the advantages of the passive system: simple, robust and low-cost operation using reliable and proven components.

  18. CHANGES SDSS: the development of a Spatial Decision Support System for analysing changing hydro-meteorological risk

    NASA Astrophysics Data System (ADS)

    van Westen, Cees; Bakker, Wim; Zhang, Kaixi; Jäger, Stefan; Assmann, Andre; Kass, Steve; Andrejchenko, Vera; Olyazadeh, Roya; Berlin, Julian; Cristal, Irina

    2014-05-01

    Within the framework of the EU FP7 Marie Curie Project CHANGES (www.changes-itn.eu) and the EU FP7 Copernicus project INCREO (http://www.increo-fp7.eu) a spatial decision support system is under development with the aim to analyse the effect of risk reduction planning alternatives on reducing the risk now and in the future, and support decision makers in selecting the best alternatives. The Spatial Decision Support System will be composed of a number of integrated components. The Risk Assessment component allows to carry out spatial risk analysis, with different degrees of complexity, ranging from simple exposure (overlay of hazard and assets maps) to quantitative analysis (using different hazard types, temporal scenarios and vulnerability curves) resulting into risk curves. The platform does not include a component to calculate hazard maps, and existing hazard maps are used as input data for the risk component. The second component of the SDSS is a risk reduction planning component, which forms the core of the platform. This component includes the definition of risk reduction alternatives (related to disaster response planning, risk reduction measures and spatial planning) and links back to the risk assessment module to calculate the new level of risk if the measure is implemented, and a cost-benefit (or cost-effectiveness/ Spatial Multi Criteria Evaluation) component to compare the alternatives and make decision on the optimal one. The third component of the SDSS is a temporal scenario component, which allows to define future scenarios in terms of climate change, land use change and population change, and the time periods for which these scenarios will be made. The component doesn't generate these scenarios but uses input maps for the effect of the scenarios on the hazard and assets maps. The last component is a communication and visualization component, which can compare scenarios and alternatives, not only in the form of maps, but also in other forms (risk curves, tables, graphs). The envisaged users of the platform are organizations involved in planning of risk reduction measures, and that have staff capable of visualizing and analysing spatial data at a municipal scale.

  19. Iterative Reconstruction in MRI Using Iterative Methods

    E-print Network

    Fessler, Jeffrey A.

    MRI. Motion... #12;12 Back to Basic Signal Model s(t) = f(r)e-i2k(t)·r dr Goal: reconstruct f(r) from yyy = (y with system matrix AAA = {ai j}: yyy = AAA fff +. Goal: estimate coefficients (pixel values) fff = (f1,..., fM) from yyy. #12;13 Small Pixel Size Does Not Matter x true -128 0 127 -128 0 127 0 2 N=32 -128 0 127 -128

  20. Analysis and Design of Iterative Learning Control Strategies for UPS Inverters

    Microsoft Academic Search

    Heng Deng; Ramesh Oruganti; Dipti Srinivasan

    2007-01-01

    In this paper, two iterative-learning-based control methods for uninterruptible power system (UPS) inverters, viz., direct iterative learning controller (direct ILC) and hybrid iterative learning controller (hybrid ILC), are proposed. In both methods, a zero-phase filter that is designed in the frequency domain is applied in order to provide compensation for the resonant peak in the system model to ensure error

  1. Iterative Spectrum Shaping with Opportunistic Multiuser Detection

    E-print Network

    Zhang, Rui

    2009-01-01

    This paper studies a new decentralized resource allocation strategy, named iterative spectrum shaping (ISS), for the multi-carrier-based multiuser communication system, where two coexisting users independently and sequentially update transmit power allocations over parallel subcarriers to maximize their individual transmit rates. Unlike the conventional iterative water-filling (IWF) algorithm that applies the single-user detection (SD) at each user's receiver by treating the interference from the other user as additional noise, the proposed ISS algorithm applies multiuser detection techniques to decode both the desired user's and interference user's messages if it is feasible, thus termed as opportunistic multiuser detection (OMD). Two encoding methods are considered for ISS: One is carrier independent encoding where independent codewords are modulated by different subcarriers for which different decoding methods can be applied; the other is carrier joint encoding where a single codeword is modulated by all t...

  2. Cyclic game dynamics driven by iterated reasoning.

    PubMed

    Frey, Seth; Goldstone, Robert L

    2013-01-01

    Recent theories from complexity science argue that complex dynamics are ubiquitous in social and economic systems. These claims emerge from the analysis of individually simple agents whose collective behavior is surprisingly complicated. However, economists have argued that iterated reasoning--what you think I think you think--will suppress complex dynamics by stabilizing or accelerating convergence to Nash equilibrium. We report stable and efficient periodic behavior in human groups playing the Mod Game, a multi-player game similar to Rock-Paper-Scissors. The game rewards subjects for thinking exactly one step ahead of others in their group. Groups that play this game exhibit cycles that are inconsistent with any fixed-point solution concept. These cycles are driven by a "hopping" behavior that is consistent with other accounts of iterated reasoning: agents are constrained to about two steps of iterated reasoning and learn an additional one-half step with each session. If higher-order reasoning can be complicit in complex emergent dynamics, then cyclic and chaotic patterns may be endogenous features of real-world social and economic systems. PMID:23441191

  3. Lessons we learned from high-throughput and top-down systems biology analyses about glioma stem cells.

    PubMed

    Mock, Andreas; Chiblak, Sara; Herold-Mende, Christel

    2014-01-01

    A growing body of evidence suggests that glioma stem cells (GSCs) account for tumor initiation, therapy resistance, and the subsequent regrowth of gliomas. Thus, continuous efforts have been undertaken to further characterize this subpopulation of less differentiated tumor cells. Although we are able to enrich GSCs, we still lack a comprehensive understanding of GSC phenotypes and behavior. The advent of high-throughput technologies raised hope that incorporation of these newly developed platforms would help to tackle such questions. Since then a couple of comparative genome-, transcriptome- and proteome-wide studies on GSCs have been conducted giving new insights in GSC biology. However, lessons had to be learned in designing high-throughput experiments and some of the resulting conclusions fell short of expectations because they were performed on only a few GSC lines or at one molecular level instead of an integrative poly-omics approach. Despite these shortcomings, our knowledge of GSC biology has markedly expanded due to a number of survival-associated biomarkers as well as glioma-relevant signaling pathways and therapeutic targets being identified. In this article we review recent findings obtained by comparative high-throughput analyses of GSCs. We further summarize fundamental concepts of systems biology as well as its applications for glioma stem cell research. PMID:23530497

  4. Meat Production in a Feedlot System of Zebu—Holstein Steers and Heifers with Dairy Genetics: Productive and Biological Analyses

    PubMed Central

    Menezes, Gustavo Chamon de Castro; Valadares Filho, Sebastiăo de Campos; Ruas, José Reinaldo Mendes; Detmann, Edenio; Menezes, Arismar de Castro; Zanett, Diego; Mariz, Lays Débora Silva; Rennó, Luciana Navajas; da Silva Junior, Jarbas Miguel

    2014-01-01

    The aim of this study was to evaluate the productive and biological efficiency of steers and heifers from dairy genetics in a feedlot system in terms of meat production. Twenty-four steers and 24 heifers at 10 monthes of age, (3/4) Zebu × (1/4) Holstein were utilized. They were distributed over four feedlot times, 30, 60, 90, and 120 days with four replications for each sex, and were slaughtered at the end of each period. The productive and biological analyses were performed through comparative slaughter to determine the body composition. Heifers presented with greater intakes (P < 0.05) of dry matter in grams per kg of body weight. Steers presented with a greater (P < 0.05) final empty body weight, carcass gain, cold carcass weight, and meat proportion in the carcass; however, heifers presented with a greater subcutaneous fat thickness (P < 0.05) and, consequently, a greater (P < 0.05) fat proportion in the carcass. We conclude that steers are more efficient in their productive performance than heifers in a feedlot. For the finishing carcass fat cover, heifers need 90 days in the feedlot. The net energy requirements for maintenance are 67?kcal/EBW0.75/d, and the net requirements of energy (NEg) and protein (NPg) for gain can be estimated by the following equations: NEg(Mcal/d) = 0.067 × EBW0.75 × EBG1.095 and NPg = 162 × EBG ? 5.62 × RE for the two sexes. PMID:25574483

  5. Molecular Evidence for the Inverse Comorbidity between Central Nervous System Disorders and Cancers Detected by Transcriptomic Meta-analyses

    PubMed Central

    Tabarés-Seisdedos, Rafael; Baudot, Anaďs; Valencia, Alfonso

    2014-01-01

    There is epidemiological evidence that patients with certain Central Nervous System (CNS) disorders have a lower than expected probability of developing some types of Cancer. We tested here the hypothesis that this inverse comorbidity is driven by molecular processes common to CNS disorders and Cancers, and that are deregulated in opposite directions. We conducted transcriptomic meta-analyses of three CNS disorders (Alzheimer's disease, Parkinson's disease and Schizophrenia) and three Cancer types (Lung, Prostate, Colorectal) previously described with inverse comorbidities. A significant overlap was observed between the genes upregulated in CNS disorders and downregulated in Cancers, as well as between the genes downregulated in CNS disorders and upregulated in Cancers. We also observed expression deregulations in opposite directions at the level of pathways. Our analysis points to specific genes and pathways, the upregulation of which could increase the incidence of CNS disorders and simultaneously lower the risk of developing Cancer, while the downregulation of another set of genes and pathways could contribute to a decrease in the incidence of CNS disorders while increasing the Cancer risk. These results reinforce the previously proposed involvement of the PIN1 gene, Wnt and P53 pathways, and reveal potential new candidates, in particular related with protein degradation processes. PMID:24586201

  6. The Evolution Of Phrase Structure In Bayesian Iterated Artificial Language Learning: A Linguistic System’s Evolution After The Emergence Of An Unbounded Combinatorial Capacity 

    E-print Network

    Saldana, Carmen

    2013-08-15

    An elementary fact about language is that it is a system of discrete infinity whose source is recursion and reveals itself as Phrase Structure Grammar. This is the cause and effect of something that we might call unique to humans. We are the only...

  7. Congress threatens ITER over cost

    E-print Network

    experiment. The United States pulled out of the ITER project in 1998 after Congress expressed frustration put in place by the Department of Health and Human Services (DHHS) in 1976, and define tricky concepts

  8. Mode conversion in ITER

    NASA Astrophysics Data System (ADS)

    Jaeger, E. F.; Berry, L. A.; Myra, J. R.

    2006-10-01

    Fast magnetosonic waves in the ion cyclotron range of frequencies (ICRF) can convert to much shorter wavelength modes such as ion Bernstein waves (IBW) and ion cyclotron waves (ICW) [1]. These modes are potentially useful for plasma control through the generation of localized currents and sheared flows. As part of the SciDAC Center for Simulation of Wave-Plasma Interactions project, the AORSA global-wave solver [2] has been ported to the new, dual-core Cray XT-3 (Jaguar) at ORNL where it demonstrates excellent scaling with the number of processors. Preliminary calculations using 4096 processors have allowed the first full-wave simulations of mode conversion in ITER. Mode conversion from the fast wave to the ICW is observed in mixtures of deuterium, tritium and helium3 at 53 MHz. The resulting flow velocity and electric field shear will be calculated. [1] F.W. Perkins, Nucl. Fusion 17, 1197 (1977). [2] E.F. Jaeger, L.A. Berry, J.R. Myra, et al., Phys. Rev. Lett. 90, 195001-1 (2003).

  9. Finite element response sensitivity, probabilistic response and reliability analyses of structural systems with applications to earthquake engineering

    E-print Network

    Barbato, Michele

    2007-01-01

    My research on sensitivity and reliability analyses hasand reliability analysis provides an ideal researchReliability and Sensitivity Meth- ods for Performance-Based Engineering” Report PEER 2003/14, Pacific Earth- quake Engineering Research

  10. Use of remote imagery to analyse spatial impacts of the Chaitén volcano eruption (Chile) in fluvial systems

    NASA Astrophysics Data System (ADS)

    Ulloa, Héctor; Iroumé, Andrés; Picco, Lorenzo; Mao, Luca; Lenzi, Mario

    2015-04-01

    The processes associated with the 2008 eruption of the Chaitén Volcano (south of Chile) generated morphological, ecological, and social disturbances. These disturbances were changes in the channel widths, vegetated islands and riparian forests. Changes in the river systems continued to occur years after the eruption due to hydrological processes induced indirectly by the volcanic eruption. This study analyzes the morphological changes in a river segment of three basins (Blanco, El Amarillo and Rayas) located near the Chaiten volcano, through an analysis of a sequence of remote images. The three watersheds were subjected to different disturbance intensities, depending on the type of dominant volcanic processes. In addition, changes were analysed by comparing two study periods, the first associated to the effusive and explosive period of the eruption, and the second after this period. In the first period mean channel widths increased by 91% (38 m/year), 6% (7 m/year) and 3% (11 m/year) for the Blanco, El Amarillo and Rayas rivers, respectively. In the second period, the variations of the mean channel widths were 19% (4 m/year), 2% (2 m/year) and 4% (5 m/year) for same rivers. On the other hand, the number of islands decreased annually by 15 and 16% on the Blanco River, 4 and 3%, in the El Amarillo River and 9 and 12% in the Rayas, in the first and second periods, respectively. The magnitude of active channel changes reflects the scale of the dominant volcanic processes in each watershed. While in the second study period strong changes continue to occur mainly at the level of the islands. This research is being developed within the framework of Project FONDECYT 1141064.

  11. Thermal infrared data analyses of Meteor Crater, Arizona: Implications for Mars spaceborne data from the Thermal Emission Imaging System

    NASA Astrophysics Data System (ADS)

    Wright, Shawn P.; Ramsey, Michael S.

    2006-02-01

    Thermal infrared (TIR) data from the Earth-orbiting Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument are used to identify the lithologic distribution of the Meteor Crater ejecta blanket. Thermal emission laboratory spectra were obtained for collected samples, and spectral deconvolution was performed on ASTER emissivity data using both image and sample end-members. Comparison of the spaceborne ASTER data to the airborne Thermal Infrared Multispectral Scanner (TIMS) data was used to validate the ASTER end-member analyses. The ASTER image end-member analysis agrees well with past studies considering the effects of resolution degradation. The work at Meteor Crater has direct bearing on the interpretation of Thermal Emission Imaging System (THEMIS) data currently being returned from Mars. ASTER and THEMIS have similar spatial and spectral resolutions, and Meteor Crater serves as an analog for similar-sized impact sites on Mars. These small impact craters have not been studied in detail owing to the low spatial resolution of past orbiting TIR instruments. Using the same methodology as that applied to Meteor Crater, THEMIS TIR data of a provisionally named Winslow Crater (~1 km) impact crater in Syrtis Major are analyzed. The crater rim and ejecta blanket were found to contain larger block sizes and a lower albedo than the surrounding ejecta-free plain, indicating a young impact age. The composition of the rim, ejecta, and surrounding plain is determined to be dominated by basalt; however, potential stratigraphy has also been identified. Results of this work could be extended to future investigations using THEMIS data.

  12. Modular transcriptional repertoire analyses of adults with systemic lupus erythematosus reveal distinct type I and type II interferon signatures

    PubMed Central

    Chiche, Laurent; Jourde-Chiche, Noémie; Whalen, Elizabeth; Presnell, Scott; Gersuk, Vivian; Dang, Kristen; Anguiano, Esperanza; Quinn, Charlie; Burtey, Stéphane; Berland, Yvon; Kaplanski, Gilles; Harle, Jean-Robert; Pascual, Virginia; Chaussabel, Damien

    2014-01-01

    Objective The role for interferon (IFN)-? in systemic lupus erythematosus (SLE) pathogenesis is strongly supported by gene expression studies. The aim of this study was to improve characterization of the blood-IFN signature in adult SLE patients. Methods Consecutive patients were enrolled and followed-up prospectively. Microarray data were generated using Illumina beadchips. A modular transcriptional repertoire was employed as a framework for the analysis. Results Our repertoire of 260 modules, which consist of co-clustered gene sets, included 3 IFN-annotated modules (M1.2, M3.4 and M5.12) that were strongly up-regulated in SLE patients. A modular IFN signature (mIS) was observed in 54/62 (87%) patients or 131/157 (83%) longitudinal samples. The IFN signature was more complex than expected with each module displaying a distinct activation threshold (M1.2analyses revealed both stable (M1.2) and variable (M3.4 and M5.12) components of mIS over time in single patients. Interestingly, mining of other datasets suggested that M3.4 and M5.12 could be also driven by INF-? and ?. Conclusion Modular repertoire analysis reveals complex IFN signatures in SLE, not restricted to the previous IFN-? signature, but involving also ? and ? IFNs. PMID:24644022

  13. FY01 Supplemental Science and Performance Analyses, Volume 2: Performance Analyses, Rev. 00

    SciTech Connect

    P. N. Swift

    2001-07-17

    This document describes the supplemental analyses that have been performed and the results incorporating those analyses into a supplemental Total Systems Performance Analyses (TSPA). Volume 2 describes the performance assessment analyses conducted using the updated information documented in Volume 1.

  14. Rayleigh Quotient Iteration in 3D, Deterministic Neutron Transport

    SciTech Connect

    Slaybaugh, R [University of Wisconsin] [University of Wisconsin; Evans, Thomas M [ORNL] [ORNL; Davidson, Gregory G [ORNL] [ORNL; Wilson, P. [University of Wisconsin] [University of Wisconsin

    2012-01-01

    Today's "grand challenge" neutron transport problems require 3-D meshes with billions of cells, hundreds of energy groups, and accurate quadratures and scattering expansions. Leadership-class computers provide platforms on which high-fidelity fluxes can be calculated. However, appropriate methods are needed that can use these machines effectively. Such methods must be able to use hundreds of thousands of cores and have good convergence properties. Rayleigh quotient iteration (RQI) is an eigenvalue solver that has been added to the Sn code Denovo to address convergence. Rayleigh quotient iteration is an optimal shifted inverse iteration method that should converge in fewer iterations than the more common power method and other shifted inverse iteration methods for many problems of interest. Denovo's RQI uses a new multigroup Krylov solver for the fixed source solutions inside every iteration that allows parallelization in energy in addition to space and angle. This Krylov solver has been shown to scale successfully to 200,000 cores: for example one test problem scaled from 69,120 cores to 190,080 cores with 98% efficiency. This paper shows that RQI works for some small problems. However, the Krylov method upon which it relies does not always converge because RQI creates ill-conditioned systems. This result leads to the conclusion that preconditioning is needed to allow this method to be applicable to a wider variety of problems.

  15. Testing of ITER central solenoid coil insulation in an array

    SciTech Connect

    Jayakumar, R.; Martovetsky, N.N.; Perfect, S.A. [and others

    1995-09-29

    A glass-polyimide insulation system has been proposed by the US team for use in the Central Solenoid (CS) coil of the international Thermonuclear Experimental Reactor (ITER) machine and it is planned to use this system in the CS model coil inner module. The turn insulation will consist of 2 layers of combined prepreg and Kapton. Each layer is 50% overlapped with a butt wrap of prepreg and an overwrap of S glass. The coil layers will be separated by a glass-resin composite and impregnated in a VPI process. Small scale tests on the various components of the insulation are complete. It is planned to fabricate and test the insulation in a 4 x 4 insulated CS conductor array which will include the layer insulation and be vacuum impregnated. The conductor array will be subjected to 20 thermal cycles and 100000 mechanical load cycles in a Liquid Nitrogen environment. These loads are similar to those seen in the CS coil design. The insulation will be electrically tested at several stages during mechanical testing. This paper will describe the array configuration, fabrication: process, instrumentation, testing configuration, and supporting analyses used in selecting the array and test configurations.

  16. ITER ECH and LFS Reflectometer waveguide testing

    NASA Astrophysics Data System (ADS)

    Bigelow, Tim; Hanson, Greg; Bull, Dianne; Caughman, John; Rasmussen, David; Wilgen, John

    2010-11-01

    The ITER project requires overmoded millimeter waveguide for electron cyclotron heating (ECH) and also the low-field side (LFS) reflectometer diagnostic. The ITER systems will use circular corrugated waveguide due its low loss and good polarization purity and launch beam qualities. The ECH application is narrow band and the reflectometer system requires broadband capability. A number of prototype components such as miter bends, straight sections, and vacuum pumpouts have been procured from industrial suppliers. The ECH system requires water cooling and good vacuum for reliable operation. Both systems will have similar straightness requirements to minimize unintentional mode conversion. The reflectometer system vacuum windows will be supplied by the US and must operate over a wide bandwidth with minimum reflection. Low power tests of mode purity, loss, and reflections are being performed on all components and high power tests are planned for the ECH components. Mode purity tests are performed by antenna pattern analysis with a high mode purity feed using both tapers or a horn/lens combination.

  17. Development of ITER 15 MA ELMy H-mode Inductive Scenario

    SciTech Connect

    Kessel, C. E.; Campbell, D.; Gribov, Y.; Saibene, G.; Ambrosino, G.; Casper, T.; Cavinato, M.; Fujieda, H.; Hawryluk, R.; Horton, L. D.; Kavin, A.; Kharyrutdinov, R.; Koechl, F.; Leuer, J.; Loarte, A.; Lomas, P. J.; Luce, T.; Lukash, V.; Mattei, M.; Nunes, I.; Parail, V.; Polevoi, A.; Portone, A.; Sartori, R.; Sips, A. C.C.; Thomas, P. R.; Welander, A.; Wesley, J.

    2008-10-16

    The poloidal field (PF) coil system on ITER, which provides both feedforward and feedback control of plasma position, shape, and current, is a critical element for achieving mission performance. Analysis of PF capabilities has focused on the 15 MA Q = 10 scenario with a 300-500 s flattop burn phase. The operating space available for the 15 MA ELMy H-mode plasma discharges in ITER and upgrades to the PF coils or associated systems to establish confidence that ITER mission objectives can be reached have been identified. Time dependent self-consistent free-boundary calculations were performed to examine the impact of plasma variability, discharge programming, and plasma disturbances. Based on these calculations a new reference scenario was developed based upon a large bore initial plasma, early divertor transition, low level heating in L-mode, and a late H-mode onset. Equilibrium analyses for this scenario indicate that the original PF coil limitations do not allow low li (<0.8) operation or lower flux states, and the flattop burn durations were predicted to be less than the desired 400 s. This finding motivates the expansion of the operating space, considering several upgrade options to the PF coils. Analysis was also carried out to examine the feedback current reserve required in the CS and PF coils during a series of disturbances and a feasibility assessment of the 17 MA scenario was undertaken. Results of the studies show that the new scenario and modified PF system will allow a wide range of 15 MA 300-500 s operation and more limited but finite 17 MA operation.

  18. Assessing the Reliability of Socio-technical Systems

    Microsoft Academic Search

    Andreas Gregoriades; Alistair Sutcliffe; Jae-Eun Shin

    2002-01-01

    This paper presents a Bayesian belief network (BBN) approach for socio technical system reliability assessment. A human error model (BBN) quantifies error influences arising from user knowledge, ability and task environment, combined with factors describing the complexity of user action and user interface quality. System reliability evaluation is achieved by the Scenario Reliability analyser tool, which enables the iterative manipulation

  19. Tokamak dust in ITER -- Safety issues and R and D supporting dust limits

    SciTech Connect

    McCarthy, K.A.; Petti, D.A.; Carmack, W.J.; Gorman, S.V.

    1998-07-01

    Tokamak dust is an important contributor to the source term in ITER safety analyses. In this paper the authors present results of R and D at the INEEL to characterize tokamak dust, and which has been used to set safety limits on dust for ITER. They present the results of analysis of particulate collected from three operating tokamaks: DIII-D at General Atomics, TFTR at Princeton Plasma Physics Laboratory, and Alcator C-MOD at Massachusetts Institute of Technology, and analysis of particulate produced in SIRENS, a disruption simulator at North Carolina State University. Analyses done include characterization of particulate to produce particle size distributions, chemical analysis, and measurement of effective surface area. The safety limits on dust in ITER have evolved during the EDA as more data have become available. The safety limits specified in NSSR-2 envelope the majority of the data, and provide conservatism to account for the uncertainty in extrapolation of the data to ITER.

  20. 4S Peak Filling – baseline estimation by iterative mean suppression

    PubMed Central

    Liland, Kristian Hovde

    2015-01-01

    A novel baseline estimation procedure building on previously published works is presented. • The core of the estimation is an iterative spectrum suppression consisting of a moving window minimum replacement (adapted from Friedrichs [1]). • Four, easily understandable, parameters control placement of the baseline relative to the noise band around the signal (adapted from Eilers [2]) and the flexibility in different situations. • The method is especially suited for non-linear baselines with local variations and for resolving peak clusters in qualitative analyses.

  1. Construction Safety Forecast for ITER

    SciTech Connect

    cadwallader, lee charles

    2006-11-01

    The International Thermonuclear Experimental Reactor (ITER) project is poised to begin its construction activity. This paper gives an estimate of construction safety as if the experiment was being built in the United States. This estimate of construction injuries and potential fatalities serves as a useful forecast of what can be expected for construction of such a major facility in any country. These data should be considered by the ITER International Team as it plans for safety during the construction phase. Based on average U.S. construction rates, ITER may expect a lost workday case rate of < 4.0 and a fatality count of 0.5 to 0.9 persons per year.

  2. Iterative analysis of strong coupling effects in semiselective J spectroscopy

    NASA Astrophysics Data System (ADS)

    Sándor, Péter; Morris, Gareth A.; Gibbs, Andrew

    A computer program for the iterative analysis of semiselective J spectra (A. Bax, J. Magn. Reson.52, 330 (1983)) is described, and experimental and calculated f 1 cross sections through semiselective 2D J spectra for the three-spin system of fumaric acid monoethyl ester and the five-spin system of thiophene are compared.

  3. An advanced LIF-PLV system for analysing the hydrodynamics in a laboratory bubble column at higher void fractions

    Microsoft Academic Search

    D. Bröder; M. Sommerfeld

    2002-01-01

    Bubble columns are widely used in the chemical industry and biotechnology. Flow and turbulence in such an apparatus are induced by the bubble rise, and the bubble behaviour is strongly affected by swarm effects (i.e. the interaction between bubbles). For analysing the bubble swarm behaviour and simultaneously evaluating the flow structure and bubble-induced turbulence, a bubble column of 140 mm

  4. Design, Analyses, and Fabrication Procedure of Amtec Cell, Test Assembly, and Radioisotope Power System for Outer-Planet Missions

    NASA Astrophysics Data System (ADS)

    Schock, A.; Noravian, H.; Or, C.; Kumar, V.

    2002-04-01

    This paper describes the results of OSC's department of energy (DOE)-sponsored alkali metal thermal-to-electric conversion (AMTEC) generator studies. The paper was prepared in response to an invitation from the International Astronautic Federation for the presentation of a 1-h keynote lecture on our AMTEC studies at the Space Nuclear Power and Propulsion Systems session of the 48th International Astronautical Congress. The paper covers a broad range of topics, which explains its unusual length. After presenting the background of those studies and the operational principles of the AMTEC converters, it describes a novel methodology for the coupled solution of the interdependent thermal, electrical, and fluid flow differential and integral equations governing their performance, and the application of that procedure to OSC's recommended cell design. As explained in the paper, that design was the result of parametric analyses of 35 cell design variations to determine the individual effects of 27 design parameters and various operating parameters on the cell's power output, efficiency, and critical temperatures. The analysis revealed a method of substantially improving the cell's performance by enhancing the internal reflectivity of the cell wall, and identified a specific cell wall composition and coating to achieve that goal. The paper presents a set of OSC-recommended cell design parameters for the ultimate long-service flight generators, as well as a set of parameters for an interim cell design for planned short-term ground tests. The primary difference between them is that the ultimate design employs refractory metal components to enhance compatibility with high-temperature sodium vapor, while the interim design is based on stainless steel, nickel, and Haynes-25, which are expected to be adequate for initial short-term tests, but not for long-duration missions at high operating temperatures. The paper also presents a detailed fabrication sequence for the recommended interim cell design, which is being implemented by AMPS, Inc., for a DOE-sponsored technology development program. It then describes the extension of that analytical procedure to a variety of OSC-designed radioisotope-heated generators employing the recommended cell design, with particular attention to the thermal insulation between the outside of the 16 cells and the inside of the generator housing. The studies found that the performance of the generator is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered (i.e., graded-length) multifoil insulation. The paper then examines the performance of the OSC generator designs for various fuel loadings, output voltages, and mission phases, and assesses their ability to meet the stipulated temperature constraints and power demands of the Europa Orbiter and Pluto Express missions under consideration by NASA. Finally, it presents an OSC-recommended design and fabrication procedure of an electrically heated four-cell test assembly with hybrid insulation to simulate the prototypic 16-cell generator. That test assembly will be analyzed by OSC, built by AMPS, and tested by the Air Force Phillips Laboratory (AFPL), to check the validity of the analytical predictions. The reason for basing the recommended test assembly on the interim rather than the ultimate refractory metal cell design is to avoid the delays required to develop the new technology for the latter.

  5. Lidar Analyses

    NASA Technical Reports Server (NTRS)

    Spiers, Gary D.

    1995-01-01

    A brief description of enhancements made to the NASA MSFC coherent lidar model is provided. Notable improvements are the addition of routines to automatically determine the 3 dB misalignment loss angle and the backscatter value at which the probability of a good estimate (for a maximum likelihood estimator) falls to 50%. The ability to automatically generate energy/aperture parametrization (EAP) plots which include the effects of angular misalignment has been added. These EAP plots make it very easy to see that for any practical system where there is some degree of misalignment then there is an optimum telescope diameter for which the laser pulse energy required to achieve a particular sensitivity is minimized. Increasing the telescope diameter above this will result in a reduction of sensitivity. These parameterizations also clearly show that the alignment tolerances at shorter wavelengths are much stricter than those at longer wavelengths. A brief outline of the NASA MSFC AEOLUS program is given and a summary of the lidar designs considered during the program is presented. A discussion of some of the design trades is performed both in the text and in a conference publication attached as an appendix.

  6. Sensitivity analyses and simulations of a full-scale experimental membrane bioreactor system using the activated sludge model No. 3 (ASM3).

    PubMed

    Ruiz, L M; Rodelas, P; Pérez, J I; Gómez, M A

    2015-01-01

    An ASM3-based model was implemented in the numerical software MATHEMATICA where sensitivity analyses and simulations of a membrane bioreactor (MBR) system were carried out. These results were compared with those obtained using the commercial simulator WEST. Predicted values did not show significant variations between both software and simulations showed that the most influential operational conditions were influent flow rate and concentrations and bioreactor volumes. On the other hand, sensitivity analyses were carried out with both software programs for the same five outputs: COD, ammonium and nitrate concentrations in the effluent, total suspended solids concentration and oxygen uptake rate in the aerobic bioreactor. Similar results were in general obtained in both cases and according to these analyses, the most significant inputs over the model predictions were growth and storage heterotrophic biomass yields and decay coefficient. Other parameters related to the hydrolysis process or to the autotrophic biomass also significantly influenced model outputs. PMID:25594125

  7. Human factors evaluation of remote afterloading brachytherapy. Supporting analyses of human-system interfaces, procedures and practices, training and organizational practices and policies. Volume 3

    SciTech Connect

    Callan, J.R.; Kelly, R.T.; Quinn, M.L. [Pacific Science & Engineering Group, San Diego, CA (United States)] [and others

    1995-07-01

    A human factors project on the use of nuclear by-product material to treat cancer using remotely operated afterloaders was undertaken by the Nuclear Regulatory Commission. The purpose of the project was to identify factors that contribute to human error in the system for remote afterloading brachytherapy (RAB). This report documents the findings from the second, third, fourth, and fifth phases of the project, which involved detailed analyses of four major aspects of the RAB system linked to human error: human-system interfaces; procedures and practices; training practices and policies; and organizational practices and policies, respectively. Findings based on these analyses provided factual and conceptual support for the final phase of this project, which identified factors leading to human error in RAB. The impact of those factors on RAB performance was then evaluated and prioritized in terms of safety significance, and alternative approaches for resolving safety significant problems were identified and evaluated.

  8. Preconditioned iterative methods for Navier-Stokes control problems

    NASA Astrophysics Data System (ADS)

    Pearson, John W.

    2015-07-01

    PDE-constrained optimization problems are a class of problems which have attracted much recent attention in scientific computing and applied science. In this paper we discuss preconditioned iterative methods for a class of (time-independent) Navier-Stokes control problems, one of the main problems of this type in the field of fluid dynamics. Having detailed the Picard-type iteration we use to solve the problems and derived the structure of the matrix system to be solved at each step, we utilize the theory of saddle point systems to develop efficient preconditioned iterative solution techniques for these problems. We also require theory of solving convection-diffusion control problems, as well as a commutator argument to justify one of the components of the preconditioner.

  9. Description of the prototype diagnostic residual gas analyzer for ITER.

    PubMed

    Younkin, T R; Biewer, T M; Klepper, C C; Marcus, C

    2014-11-01

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations. PMID:25430381

  10. Description of the prototype diagnostic residual gas analyzer for ITER

    SciTech Connect

    Younkin, T. R., E-mail: tyounkin@gatech.edu [Fusion and Materials for Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States); Georgia Institute of Technology, Woodruff School of Mechanical Engineering – Nuclear and Radiological Engineering Program, Atlanta, Georgia 30332 (United States); Biewer, T. M.; Klepper, C. C.; Marcus, C. [Fusion and Materials for Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)

    2014-11-15

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations.

  11. Theoretical in-Solution Conformational/Tautomeric Analyses for Chain Systems with Conjugated Double Bonds Involving Nitrogen(s)

    PubMed Central

    Nagy, Peter I.

    2015-01-01

    Conformational/tautomeric transformations for X=CH–CH=Y structures (X = CH2, O, NH and Y = NH) have been studied in the gas phase, in dichloromethane and in aqueous solutions. The paper is a continuation of a former study where s-cis/s-trans conformational equilibria were predicted for analogues. The s-trans conformation is preferred for the present molecules in the gas phase on the basis of its lowest internal free energy as calculated at the B97D/aug-cc-pvqz and CCSD(T)CBS (coupled-cluster singles and doubles with non-iterative triples extrapolated to the complete basis set) levels. Transition state barriers are of 29–36 kJ/mol for rotations about the central C–C bonds. In solution, an s-trans form is still favored on the basis of its considerably lower internal free energy compared with the s-cis forms as calculated by IEF-PCM (integral-equation formalism of the polarizable continuum dielectric solvent model) at the theoretical levels indicated. A tetrahydrate model in the supermolecule/continuum approach helped explore the 2solute-solvent hydrogen bond pattern. The calculated transition state barrier for rotation about the C–C bond decreased to 27 kJ/mol for the tetrahydrate. Considering explicit solvent models, relative solvation free energies were calculated by means of the free energy perturbation method through Monte Carlo simulations. These calculated values differ remarkably from those by the PCM approach in aqueous solution, nonetheless the same prevalent conformation was predicted by the two methods. Aqueous solution structure-characteristics were determined by Monte Carlo. Equilibration of conformers/tautomers through water-assisted double proton-relay is discussed. This mechanism is not viable, however, in non-protic solvents where the calculated potential of mean force curve does not predict remarkable solute dimerization and subsequent favorable orientation. PMID:25984602

  12. Energetic ions in ITER plasmas

    NASA Astrophysics Data System (ADS)

    Pinches, S. D.; Chapman, I. T.; Lauber, Ph. W.; Oliver, H. J. C.; Sharapov, S. E.; Shinohara, K.; Tani, K.

    2015-02-01

    This paper discusses the behaviour and consequences of the expected populations of energetic ions in ITER plasmas. It begins with a careful analytic and numerical consideration of the stability of Alfvén Eigenmodes in the ITER 15 MA baseline scenario. The stability threshold is determined by balancing the energetic ion drive against the dominant damping mechanisms and it is found that only in the outer half of the plasma ( r / a > 0.5 ) can the fast ions overcome the thermal ion Landau damping. This is in spite of the reduced numbers of alpha-particles and beam ions in this region but means that any Alfvén Eigenmode-induced redistribution is not expected to influence the fusion burn process. The influence of energetic ions upon the main global MHD phenomena expected in ITER's primary operating scenarios, including sawteeth, neoclassical tearing modes and Resistive Wall Modes, is also reviewed. Fast ion losses due to the non-axisymmetric fields arising from the finite number of toroidal field coils, the inclusion of ferromagnetic inserts, the presence of test blanket modules containing ferromagnetic material, and the fields created by the Edge Localised Mode (ELM) control coils in ITER are discussed. The greatest losses and associated heat loads onto the plasma facing components arise due to the use of the ELM control coils and come from neutral beam ions that are ionised in the plasma edge.

  13. Networking Theories by Iterative Unpacking

    ERIC Educational Resources Information Center

    Koichu, Boris

    2014-01-01

    An iterative unpacking strategy consists of sequencing empirically-based theoretical developments so that at each step of theorizing one theory serves as an overarching conceptual framework, in which another theory, either existing or emerging, is embedded in order to elaborate on the chosen element(s) of the overarching theory. The strategy is…

  14. Department of Energy ITER Project

    E-print Network

    that the ITER value estimate is appropriate for establishing relative contributions by the Parties in various countries, and it emphasizes the value of individual components relative to each other. It is not comparable to a traditional DOE construction project cost estimate. The credibility of such a value estimate

  15. Continued Fractions and Iterative Processes.

    ERIC Educational Resources Information Center

    Bevis, Jean H.; Boal, Jan L.

    1982-01-01

    Continued fractions and associated sequences are viewed to constitute a rich area of study for mathematics students, by supporting instruction on algebraic and computational skills, mathematical induction, convergence of sequences, and interpretation of function graphs. An iterative method of approximating square roots opens suggestions for…

  16. Iterative Methods Summer semester 2008

    E-print Network

    Gutknecht, Martin H.

    /toolbox/matlab/sparfun · Examples of "sparse Matlab" commands: sparse converts full to sparse matrix full converts sparse to . . . . . . . . . . . . . . 1-6 1.4 Iterations Based on Matrix Splittings . . . . . . . . . . . . 1-10 1.5 Krylov Subspaces Preconditioning Techniques . . . . . . . . . . 1-28 1.8.1 Preconditioning based on classical matrix splittings1

  17. Variation of volatile concentration in a magma system of Satsuma-Iwojima volcano deduced from melt inclusion analyses

    Microsoft Academic Search

    G. Saito; K Kazahaya; H Shinohara; J Stimac; Y Kawanabe

    2001-01-01

    Chemical analyses of 30 melt inclusions from Satsuma-Iwojima volcano, Japan, were carried out to investigate volatile evolution in a magma chamber beneath the volcano from about 6300yr BP to the present. Large variations in volatile concentrations of melts were observed. (1) Water concentration of rhyolitic melts decreases with time; 3–4.6wt.% at the time of latest caldera-forming eruption of Takeshima pyroclastic

  18. Joint Press Release TWELFTH ITER NEGOTIATION MEETING

    E-print Network

    Joint Press Release TWELFTH ITER NEGOTIATION MEETING Jeju, Korea, 6 December th 2005 Delegations on an Agreement on the joint implementation of the ITER international fusion energy project. This was the first/6/05 1:21 PMDraft Joint News Release Page 1 of 2http://www.iter.org/N_12_Joint_Press_Release.htm #12

  19. The Parallel Iterative Closest Point Algorithm

    Microsoft Academic Search

    Christian Langis; Michael A. Greenspan; Guy Godin

    2001-01-01

    This paper describes a parallel implementation developed to improve the time performance of the Iterative Closest Point Algorithm. Within each iteration, the correspon- dence calculations are distributed among the processor re- sources. At the end of each iteration, the results of the cor- respondence determination are communicated back to a central processor and the current transformation is calcu- lated. A

  20. Iterative turbo MKL multiuser detection and channel estimation for DS-CDMA signals

    Microsoft Academic Search

    Tuchsanai Ploysuwan; Sawat Tantiphanwadi; Prasit Teekaput

    2007-01-01

    This paper derives a new computational efficiency minimum Kullback-Leibler (MKL) iterative multiuser detector algorithm and channel estimation for DS-CDMA system. The main ideas are to design virtual trellis corresponding to each user's symbols channel delay for generating extrinsic probability in term of BCJR algorithm and channel estimator that is compatible with very short training sequence operates in an iterative fashion

  1. An Iterative Receiver for Joint Detection, Decoding, and Channel Estimation in Turbo Coded MIMO OFDM

    Microsoft Academic Search

    Jari Ylioinas; M. Juntti

    2007-01-01

    An iterative receiver using a list detector, a turbo decoder, and the space-alternating generalized expectation- maximization (SAGE) based channel estimation for a multiple- input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system is considered to jointly decode the transmitted bits and to estimate the channel state. Different iterative processing possibilities are identified and compared to each other from the performance

  2. Iterative tomographic image reconstruction using Fourier-based forward and back-projectors

    Microsoft Academic Search

    Samuel Matej; Jeffrey A. Fessler; Ivan G. Kazantsev

    2004-01-01

    Iterative image reconstruction algorithms play an increasingly important role in modern tomographic systems, espe- cially in emission tomography. With the fast increase of the sizes of the tomographic data, reduction of the computation demands of the reconstruction algorithms is of great importance. Fourier- based forward and back-projection methods have the potential to considerably reduce the computation time in iterative recon-

  3. Proposal of an Arc Detection Technique Based on RF Measurements for the ITER ICRF Antenna

    NASA Astrophysics Data System (ADS)

    Huygen, S.; Dumortier, P.; Durodié, F.; Messiaen, A.; Vervier, M.; Vrancken, M.; Wooldridge, E.

    2011-12-01

    RF arc detection is a key operational and safety issue for the ICRF system on ITER. Indeed the high voltages inside the antenna put it at risk of arcing, which could cause substantial damage. This paper describes the various possibilities explored by circuit simulation and the strategy now considered to protect the ITER ICRF antenna from RF arcs.

  4. Proposal of an Arc Detection Technique Based on RF Measurements for the ITER ICRF Antenna

    SciTech Connect

    Huygen, S.; Dumortier, P.; Durodie, F.; Messiaen, A.; Vervier, M.; Vrancken, M. [LPP/ERM-KMS, Association EURATOM-Belgian State, Brussels (Belgium); Wooldridge, E. [EURATOM/CCFE Fusion Association, Culham Science Centre (United Kingdom)

    2011-12-23

    RF arc detection is a key operational and safety issue for the ICRF system on ITER. Indeed the high voltages inside the antenna put it at risk of arcing, which could cause substantial damage. This paper describes the various possibilities explored by circuit simulation and the strategy now considered to protect the ITER ICRF antenna from RF arcs.

  5. The Models of Didactical Process Communicat?ons in Traditional and Distance Learning Systems: Analyses the State of the Art

    ERIC Educational Resources Information Center

    Railean, Elena

    2006-01-01

    This paper consists of an analysis of the state of the art of research and development for the different models of didactical processes in traditional and distance learning systems. The educational system is an open and dynamic system. In such context as the educational system, seven models of didactical process communications can be observed. The…

  6. Systems Engineering of Electric and Hybrid Vehicles

    NASA Technical Reports Server (NTRS)

    Kurtz, D. W.; Levin, R. R.

    1986-01-01

    Technical paper notes systems engineering principles applied to development of electric and hybrid vehicles such that system performance requirements support overall program goal of reduced petroleum consumption. Paper discusses iterative design approach dictated by systems analyses. In addition to obvious peformance parameters of range, acceleration rate, and energy consumption, systems engineering also considers such major factors as cost, safety, reliability, comfort, necessary supporting infrastructure, and availability of materials.

  7. An Iterative Improvement Cosynthesis Algorithm for Optimization of SOPC Architecture with Dynamically Reconfigurable FPGAs

    Microsoft Academic Search

    Radoslaw Czarnecki; Stanislaw Deniziak; Krzysztof Sapiecha

    2003-01-01

    In this work, a HW\\/SW iterative improvement co-synthesis algorithm, which allows for optimization of heterogeneous system architecture with dynamically reconfigurable FPGAs is presented. The algorithm maximizes speed of the system taking into consideration cost constraints.

  8. The Effects of Load Impedance, Line Length, and Branches in Typical Low-Voltage Channels of the BPLC Systems of Developing Countries: Transmission-Line Analyses

    Microsoft Academic Search

    Justinian Anatory; Nelson Theethayi; Rajeev Thottappillil; Mussa Kissaka; Nerey Mvungi

    2009-01-01

    This paper presents the influence of line length, number of branches (distributed and concentrated), and terminal impedances on the performance of a low-voltage broadband power-line communication channel. For analyses, the systems chosen are typical low-voltage power-line networks found in Tanzania. The parameters varied were the network's load impedances, direct line length (from transmitter to receiver), branched line lengths, and number

  9. Diagnostics of the ITER neutral beam test facility

    SciTech Connect

    Pasqualotto, R.; Serianni, G.; Agostini, M.; Brombin, M.; Dalla Palma, M.; Gazza, E.; Pomaro, N.; Rizzolo, A.; Spolaore, M.; Zaniol, B. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Sonato, P.; De Muri, M. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Dipartimento di Ingegneria Elettrica, Padova University (Italy); Croci, G. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); Gorini, G. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); CNISM, Dipartimento di Fisica, Universita degli Studi di Milano-Bicocca, Milano (Italy)

    2012-02-15

    The ITER heating neutral beam (HNB) injector, based on negative ions accelerated at 1 MV, will be tested and optimized in the SPIDER source and MITICA full injector prototypes, using a set of diagnostics not available on the ITER HNB. The RF source, where the H{sup -}/D{sup -} production is enhanced by cesium evaporation, will be monitored with thermocouples, electrostatic probes, optical emission spectroscopy, cavity ring down, and laser absorption spectroscopy. The beam is analyzed by cooling water calorimetry, a short pulse instrumented calorimeter, beam emission spectroscopy, visible tomography, and neutron imaging. Design of the diagnostic systems is presented.

  10. An improvement of the Euler-Chebyshev iterative method

    NASA Astrophysics Data System (ADS)

    Grau, Miquel; Diaz-Barrero, Jose Luis

    2006-03-01

    We present a new method for the computation of the solutions of nonlinear equations when it is necessary to use high precision. We improve the Euler-Chebyshev iterative method which is a generalization of an improvement of Newton's method. A symbolic computation allows us to find the best coefficients respect to the local order of convergence. The adaptation of the strategy presented here gives an additional iteration function with an additional evaluation of the function. It provides a lower cost if we use adaptive multi-precision arithmetics. The numerical results computed using this system, with a floating point representing a maximum of 210 decimal digits, support this theory.

  11. FEM analyses for the design and modeling of a novel flywheel energy storage system assisted by integrated magnetic bearing

    Microsoft Academic Search

    C. Zhang; P. Wu; K. J. Tseng

    2005-01-01

    A compact and efficient flywheel energy storage system is proposed in this paper. The system is assisted by integrated mechanical and magnetic bearings, the flywheel acts as the rotor of the drive system and is sandwiched between two disk type stators to save space. The combined use of active magnetic bearings, mechanical bearings and axial flux PM synchronous machine assists

  12. Energy and exergy analyses of a combined ammonia-fed solid oxide fuel cell system for vehicular applications

    Microsoft Academic Search

    Ehsan Baniasadi; Ibrahim Dincer

    2011-01-01

    In this study, both energetic and exergetic performances of a combined heat and power (CHP) system for vehicular applications are evaluated. This system proposes ammonia-fed solid oxide fuel cells based on proton conducting electrolyte (SOFC-H+) with a heat recovery option. Fuel consumption of combined fuel cell and energy storage system is investigated for several cases. The performance of the portable

  13. The iteration method for the Wahba problem solution

    NASA Astrophysics Data System (ADS)

    Kruzhilov, Ivan

    2014-12-01

    Wahba problem is the task of constrained optimization on SO(3). Solution of this task is vital for satellite attitude determination using star trackers. An iterative method having quadratic convergence is proposed. Each iteration of the proposed method is reduced to sequential rotation of the vectors and solving the system of linear algebraic equations. The method needs an initial approximation, which can be obtained by the TRIAD method. The quaternion form of the TRIAD method is given. One or two iterations are sufficient for finding the optimal solution using the proposed method. The primary advantage of the proposed method as compared with classical methods based on calculation of eigenvectors and singular decomposition is the simplicity of its implementation.

  14. Analysis and design of interleaver mappings for iteratively decoded BICM

    Microsoft Academic Search

    Jun Tan; Gordon L. Stuber

    2002-01-01

    Iterative decoding of bit-interleaved coded modulation (BICM) is analyzed. The interleaver of a BICM system is shown to provide not only time diversity gain as a channel interleaver, but also interleaving gain as a code interleaver. Our performance analysis of BICM assumes a uniform interleaver, and it is shown that the interleaving gain can be achieved at high SNR. The

  15. Enhanced Nonlinear Iterative Techniques Applied to a Nonequilibrium Plasma Flow

    E-print Network

    the partially­ionized plasma flow in the boundary layer of a tokamak fusion reactor. This system of equations describe the flow of plasma particles and energy from the edge of the reactor core into what is calledEnhanced Nonlinear Iterative Techniques Applied to a Non­equilibrium Plasma Flow D.A. Knoll and P

  16. Effective Preconditioning Techniques for Iterative Solutions of Integral Equation Methods

    E-print Network

    Gürel, Levent

    accurately with these methods by solving the radiation problem. The unknown current density on the target large systems, neither of these methods succeeds to reduce the iteration counts as desired. The main. The superiority of this preconditioner is illustrated by solving a variety of large-scale problems. 1

  17. Iterative Versus Adaptive Equalizers in Time-Variant Channels

    Microsoft Academic Search

    Clemens Buchacher; Joachim Wehinger; Mario Huemer

    2009-01-01

    This paper discusses the application of iterative versus adaptive equalizers to a universal mobile telecommunications system (UMTS) high speed downlink packet access (HSDPA) receiver. Among the investigated algorithms are the least mean square (LMS) and recursive least square (RLS) algorithms and their adaptations to code division multiple access (CDMA), such as Griffith's algorithm, as well as the conjugate gradient (CG)

  18. Local, hierarchic, and iterative reconstructors for adaptive optics

    E-print Network

    MacMynowski, Douglas G. - MacMynowski, Douglas G.

    Local, hierarchic, and iterative reconstructors for adaptive optics Douglas G. MacMartin Department September 6, 2002; revised manuscript received January 31, 2003; accepted January 31, 2003 Adaptive optics- mar Observatory adaptive optics system. The analysis is general enough to also be applicable to active

  19. Conceptual design of the ITER TF model coil

    Microsoft Academic Search

    P. Libeyre; B. Bertrand; P. Decool; B. Turck; P. Komarek; W. Maurer; A. Ulbricht; G. Zahn; M. Spadoni; E. Salpietro

    1996-01-01

    The aims of the toroidal field (TF) model coil are to test the manufacturing feasibility of the ITER TF magnet concepts, to assess the reliability of the fully integrated system by dedicated testing and to qualify the quality assurance and the testing methods. The 3.8 m long racetrack shaped TFMC will be tested in the TOSKA facility at Karlsruhe in

  20. A Policy Iteration Technique for Time Elapse over Template Polyhedra

    E-print Network

    Dang, Thao

    A Policy Iteration Technique for Time Elapse over Template Polyhedra (Extended Abstract) Sriram to compute over-approximations of the time trajectories of an affine hybrid system using template polyhedra. Such polyhedra are obtained by conjoining a set of inequality templates with varying constant coefficients. Given