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1

RAMI Analyses of Heating Neutral Beam and Diagnostic Neutral Beam Systems for ITER  

SciTech Connect

A RAMI (Reliability, Availability, Maintainability, Inspectability) analysis has been performed for the heating (and current drive) neutral beam (HNB) and diagnostic neutral beam (DNB) systems of the ITER device. The objective of these analyses is to implement RAMI engineering requirements for design and testing to prepare a reliability-centred plan for commissioning, operation, and maintenance of the system in the framework of technical risk control to support the overall ITER Project. These RAMI requirements will correspond to the RAMI targets for the ITER project and the compensating provisions to reach them as deduced from the necessary actions to decrease the risk level of the function failure modes. The RAMI analyses results have to match with the procurement plan of the systems.

Chang, D. H. [Korea Atomic Energy Research Institute(KAERI), Daejeon 305-353 (Korea, Republic of); Lee, S. [ITER-Korea Domestic Agency, National Fusion Research Institute(NFRI), Daejeon 305-333 (Korea, Republic of); Hemsworth, R.; Houtte, D. van; Okayama, K.; Sagot, F.; Schunke, B.; Svensson, L. [ITER Organization, 13067 St. Paul-lez-Durance Cedex (France)

2011-09-26

2

Development of the PACTITER code and its application to safety analyses of ITER Primary Cooling Water System  

Microsoft Academic Search

The PACTITER code derives from the PACTOLE code, developed by the CEA for predicting activated corrosion products (ACPs) in PWR primary circuits. The operating conditions, material compositions and water chemistry of the various Primary Heat Transfer Systems (PHTS) of the International Thermonuclear Experimental Reactor (ITER) made mandatory the adaptation of the PACTOLE code.PACTITER was developed on the basis of dedicated

L. Di Pace; F. Dacquait; P. Schindler; V. Blet; F. Nguyen; Y. Philibert; B. Larat

2007-01-01

3

The ITER vacuum systems  

NASA Astrophysics Data System (ADS)

ITER is a large vacuum facility which comprises many service, diagnostic and monitoring vacuum sub-systems as well as three large cryogenic pumping systems for evacuation and maintenance of the required pressure levels. Control of the gas throughput is one of the key issues affecting the performance and achievable burn time of a fusion reactor. The main pumping systems are the torus exhaust pumping, the cryopumps for the neutral beam injection systems for plasma heating, and the cryopumps for the ITER cryostat. All customized cryosorption pumps are force-cooled with supercritical helium and share a similar modular design of cryosorption pumping panels. For regeneration of the cryopumps as well as for roughing down the system volumes prior to operation, four identical sets of forepump trains are used. This paper will focus on the areas of the ITER vacuum systems which require customized developments and cannot rely on commercial solutions. The complex pumps have been tailored for the very specific applications and requirements at ITER, especially characterised by the need to be tritium compatible. An outline of the development path which was needed to come up with a sound design for the ITER cryopumps is given. The way of development is culminating in the manufacturing of 1:1 scale prototypes, which will be extensively tested in dedicated test facilities to ensure compatibility with all design requirements.

Day, C.; Murdoch, D.

2008-05-01

4

The ITER vacuum systems  

Microsoft Academic Search

ITER is a large vacuum facility which comprises many service, diagnostic and monitoring vacuum sub-systems as well as three large cryogenic pumping systems for evacuation and maintenance of the required pressure levels. Control of the gas throughput is one of the key issues affecting the performance and achievable burn time of a fusion reactor. The main pumping systems are the

C. Day; D. Murdoch

2008-01-01

5

The ITER remote maintenance system  

Microsoft Academic Search

The aim of this paper is to summarize the ITER approach to machine components maintenance. A major objective of the ITER project is to demonstrate that a future power producing fusion device can be maintained effectively and offer practical levels of plant availability. During its operational lifetime, many systems of the ITER machine will require maintenance and modification; this can

A. Tesini; J. Palmer

2008-01-01

6

MELCOR 1.8.2 Analyses in Support of ITER’s RPrS  

SciTech Connect

The International Thermonuclear Experimental Reactor (ITER) Program is performing accident analyses for ITER’s “Rapport Préliminaire de Sûreté” (Report Preliminary on Safety - RPrS) with a modified version of the MELCOR 1.8.2 code. The RPrS is an ITER safety document required in the ITER licensing process to obtain a “Décret Autorisation de Construction” (a Decree Authorizing Construction - DAC) for the ITER device. This report documents the accident analyses performed by the US with the MELCOR 1.8.2 code in support of the ITER RPrS effort. This work was funded through an ITER Task Agreement for MELCOR Quality Assurance and Safety Analyses. Under this agreement, the US was tasked with performing analyses for three accident scenarios in the ITER facility. Contained within the text of this report are discussions that identify the cause of these accidents, descriptions of how these accidents are likely to proceed, the method used to analyze the consequences of these accidents, and discussions of the transient thermal hydraulic and radiological release results for these accidents.

Brad J Merrill

2008-01-01

7

Main results of the analyses related to a few Reference Accident Sequences of NET\\/ITER tritium systems  

Microsoft Academic Search

Based on the existing conceptual design, a set of Reference Accident Sequences (RAS) has been defined by tritium system experts. This paper presents the main results related to a preliminary analysis of the following RAS for fuel cycle systems: hydrogen detonation in the isotopic separation system, rupture of a cryoline in a cryopump, fire in the long-term storage beds, and

S. Ciattaglia; L. Di. Pace; C. Rizzello; E. Visca

1993-01-01

8

Main results of the analyses related to a few reference accident sequences of NET/ITER tritium systems  

SciTech Connect

Based on the existing conceptual design, a set of Reference Accident Sequences (RAS) has been defined by tritium system experts. This paper presents the main results related to a preliminary analysis of the following RAS for fuel cycle systems: hydrogen detonation in the isotopic separation system, rupture of a cryoline in a cryopump, fire in the long-term storage beds, and mechanical faulty operation in the pellet injector. The systems and the component mode of operation have been analyzed, as well as the characteristics of all streams, the inventory of T, D, and H, and the energy released under accident conditions. Failures that could give rise to the release of tritium and/or to the formation and ignition of oxygen/hydrogen mixtures and failures that could lead to containment pressure transients are discussed and examined.

Ciattaglia, S.; Pace, L.Di.; Visca, E. (Centro Richerche Energia Frascati, Rome (Italy)); Rizzello, C. (Sistemi e Tecnologie per l'Energia SpA, Rome (Italy))

1993-06-01

9

ECRF systems for ITER  

Microsoft Academic Search

ITER, the International Thermonuclear Experimental Reactor, proposes to use electron cyclotron technology on an unprecedented scale. ECRF (electron cyclotron range of frequencies) will be used for start-up, heating, noninductive on-and off-axis current drive, and wall conditioning. Advanced gyrotron sources will be needed in order to fulfill the unique requirements imposed by these applications. Consequently, an international R&D program has been

M. Makowski

1996-01-01

10

ECRF systems for ITER  

SciTech Connect

ITER, the International Thermonuclear Experimental Reactor, proposes to use electron cyclotron technology on an unprecedented scale. ECRF (electron cyclotron range of frequencies) will be used for start-up, heating, noninductive on- and off-axis current drive, and wall conditioning. Advanced gyrotron sources will be needed in order to fulfill the unique requirements imposed by these applications. Consequently, an international R and D program has been undertaken to develop 170 GHz, CW, 1 MW, {approximately}50% efficient tubes. The rationale for the R and D program is presented and design issues relating to the efficient generation, transmission, and delivery to the plasma of over 50 MW of ECRF power are discussed.

Makowski, M. [Max-Planck Inst. fuer Plasmaphysik, Garching bei Muenchen (Germany). ITER Joint Work Site

1996-06-01

11

ITER system study---Safety aspects  

SciTech Connect

One of the tasks of the ITER Systems Analysis Group has been safety and environmental analyses. The safety analyses show that radiological doses from operational effluents and accidents are consistent with anticipated regulatory dose limits. To improve safety further and to meet the ambitious goal of passive safety,'' further efforts to reduce inventories of tritium and activation products are proposed. Most major safety issues are now associated with Plasma Facing Components (PFC). 2 tabs.

Piet, S.J. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Iida, H.; Seki, Y. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment); Raeder, J. (Max-Planck-Institut fuer Plasmaphysik, Garching (Germany, F.R.). NET Design Team); Topilski, L.N. (Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Moscow (USSR). Inst. Atomnoj Ehnergii)

1990-01-01

12

ITER neutral beam injection system  

NASA Astrophysics Data System (ADS)

A Japanese design proposal of the ITER Neutral Beam Injection System (NBS) which is consistent with the ITER common design requirements is described. The injection system is required to deliver a neutral deuterium beam of 75MW at 1.3MeV to the reactor plasma and utilized not only for plasma heating but also for current drive and current profile control. The injection system is composed of 9 modules, each of which is designed so as to inject a 1.3 MeV, 10 MW neutral beam. The most important point in the design is that the injection system is based on the utilization of a cesium-seeded volume negative ion source which can produce an intense negative ion beam with high current density at a low source operating pressure. The design value of the source is based on the experimental values achieved at JAERI. The utilization of the cesium-seeded volume source is essential to the design of an efficient and compact neutral beam injection system which satisfies the ITER common design requirements. The critical components to realize this design are the 1.3MeV, 17A electrostatic accelerator and the high voltage DC acceleration power supply, whose performances must be shown prior to the construction of the ITER NBI system.

Ohara, Yoshihiro; Tanaka, Shigeru; Akiba, Masato

1991-03-01

13

The ITER Remote Maintenance Management System  

Microsoft Academic Search

A major challenge for the ITER project is to develop and implement a Remote Maintenance System, which can deliver high Tokamak availability within the constraints of the overall ITER programme objectives.Much of the maintenance of ITER will be performed using remote handling methods and some with combined manual and remote activities working together.The organization and management of the ITER remote

Alessandro Tesini; A. C. Rolfe

2009-01-01

14

ITER Construction-Plant System Integration  

NASA Astrophysics Data System (ADS)

This brief paper introduces how the ITER will be built in the international collaboration. The ITER Organization plays a central role in constructing ITER and leading it into operation. Since most of the ITER components are to be provided in-kind from the member countries, integral project management should be scoped in advance of real work. Those include design, procurement, system assembly, testing, licensing and commissioning of ITER.

Tada, E.; Matsuda, S.

2009-02-01

15

Remote handling systems for ITER  

Microsoft Academic Search

The requirement to reduce the investment cost for ITER as compared with the 1998 ITER design, has led to a reduction in the size of the ITER machine and a number of design changes which have an impact on the remote maintenance of ITER Major components to be considered for remote handling (RH) include the divertor cassettes, shield blanket modules,

T Honda; Y Hattori; C Holloway; E Martin; Y Matsumoto; T Matsunobu; T Suzuki; A Tesini; V Baulo; R Haange; J Palmer; K Shibanuma

2002-01-01

16

ETR/ITER systems code  

SciTech Connect

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.

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

17

Performance analysis of ITER tomographic systems  

SciTech Connect

A method based on the Bayesian statistical analysis is proposed to measure the performance of ITER tomographic systems. This method can quantify the performance of the systems and helps in the diagnostic design.

Kalvin, S. [MTA KFKI--Research Institute for Particle and Nuclear Physics, EURATOM Association, P.O. Box 49, H-1525 Budapest-114 (Hungary); Ingesson, L. C. [EFDA Close Support Unit-Garching, Boltzmannstr. 2, D-85748 Garching (Germany)

2008-03-12

18

Iterative design of video communication systems  

Microsoft Academic Search

This paper reviews the design and implementation of several video telephony systems at Bellcore as a case study in iterative design. In contrast to single user compuer applications, communication systems consists of both the interconnection technology and the people who are interconnected. From a user’s point of view, the capabilities provided by the system, the rules for its use, and

Colleen Cool; Robert S. Fish; Robert E. Kraut; C. M. Lowery

1992-01-01

19

Development of pellet injection systems for ITER  

SciTech Connect

Oak Ridge National Laboratory (ORNL) has been developing innovative pellet injection systems for plasma fueling experiments on magnetic fusion confinement devices for about 20 years. Recently, the ORNL development has focused on meeting the complex fueling needs of the International Thermonuclear Experimental Reactor (ITER). In this paper, we describe the ongoing research and development activities that will lead to a ITER prototype pellet injector test stand. The present effort addresses three main areas: (1) an improved pellet feed and delivery system for centrifuge injectors, (2) a long-pulse (up to steady-state) hydrogen extruder system, and (3) tritium extruder technology. The final prototype system must be fully tritium compatible and will be used to demonstrate the operating parameters and the reliability required for the ITER fueling application.

Combs, S.K.; Gouge, M.J.; Baylor, L.R. [and others

1995-12-31

20

Verification of MELCOR Input Decks Used in ITER RPrS Analyses  

SciTech Connect

This report as part of an ITER Task Agreement, documents the verification of the MELCOR Input Computer Decks used in performing the required safety analyses to be presented in the Preliminary Safety Report (Rapport Préliminaire de Séreté, RPrS).

Richard L. Moore

2008-01-01

21

The ITER in-vessel system  

NASA Astrophysics Data System (ADS)

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.

Lousteau, D. C.

22

Nuclear modules of ITER tokamak systems code  

SciTech Connect

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.

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

1987-10-01

23

Development of pellet injection systems for ITER  

Microsoft Academic Search

Oak Ridge National Laboratory (ORNL) has been developing innovative pellet injection systems for plasma fueling experiments on magnetic fusion confinement devices for about 20 years. Recently, the ORNL development has focused on meeting the complex fueling needs of the International Thermonuclear Experimental Reactor (ITER). In this paper, we describe the ongoing research and development activities that will lead to an

S. K. Combs; M. J. Gouge; L. R. Baylor; C. R. Foust; P. W. Fisher; S. L. Milora; A. L. Quallls; D. E. Schechter; J. M. Walters

1995-01-01

24

ITER prototype fast plant system controller  

Microsoft Academic Search

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

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. Lousã; F. Piedade; L. Fernandes

2011-01-01

25

Iterative learning fuzzy inference system  

Microsoft Academic Search

This paper presents a learning fuzzy controller which can adapt with changing performance requirements. During the past decade we have witnessed a rapid growth in the number and variety of applications of fuzzy logic ranging from consumer electronics and industrial process control to decision support system and financial systems. The fuzzy controller designer faces the challenge of choosing the appropriate

S. Ashraf; E. Muhammad; F. Rashid; M. Shahzad

2009-01-01

26

An integrated design evaluation system supporting thermal-structural iterations  

Microsoft Academic Search

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

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

1998-01-01

27

Status of ITER ICH Matching System Design  

SciTech Connect

Work on the design of the ITER ICH matching system is progressing. The design has been significantly improved. The system will deliver a total power of 20 MW for long-pulse (>3000 s) operation. The present matching system has hybrid combiner-splitter circuits for ELM resilience, active matching during a shot using a double-stub-tuner circuit, decouplers between the eight inputs to each antenna, water-cooled transmission lines and matching components in the unmatched section, and air-cooled transmission lines using turbulent cooling.

Swain, D.; Goulding, R.; Rasmussen, D. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6483 (United States)

2009-11-26

28

Elastic properties of composite ITER insulation systems  

SciTech Connect

Candidate composite insulation systems were tested at 295, 76, and 4 K to determine relevant elastic property data for design and analysis use in the International Thermonuclear Experimental Reactor (ITER). Vacuum-pressure-impregnated, preimpregnated, and high-pressure laminate (G-11CR) resin systems were included. One system contained a polyimide-film electrical barrier. Tests focused on the through-thickness Young`s modulus, the interlaminar shear modulus, and the in-plane shear modulus. Subsize strain gages were used to obtain through-thickness strain measurements, and strain-gage rosettes, to measure shear strains.

Reed, R.P. [Cryogenic Materials, Inc., Boulder, CO (United States); Fabian, P.E.; Bauer-McDaniel, T.S. [Composite Technology Development, Inc., Boulder, CO (United States)

1997-06-01

29

The ITER Radial Neutron Camera Detection System  

SciTech Connect

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.

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

30

Chaos automata: iterated function systems with memory  

NASA Astrophysics Data System (ADS)

Transforming biological sequences into fractals in order to visualize them is a long standing technique, in the form of the traditional four-cornered chaos game. In this paper we give a generalization of the standard chaos game visualization for DNA sequences. It incorporates iterated function systems that are called under the control of a finite state automaton, yielding a DNA to fractal transformation system with memory. We term these fractal visualizers chaos automata. The use of memory enables association of widely separated sequence events in the drawing of the fractal, finessing the ``forgetfulness'' of other fractal visualization methods. We use a genetic algorithm to train chaos automata to distinguish introns and exons in Zea mays (corn). A substantial issue treated here is the creation of a fitness function that leads to good visual separation of distinct data types.

Ashlock, Dan; Golden, Jim

2003-07-01

31

Analyses of high power negative ion accelerators for ITER neutral beam injector (invited).  

PubMed

In JAEA, research and developments to realize high power accelerator (1 MeV, 40 AD(-) ion beams for 3600 s) for ITER have been carried out experimentally and numerically utilizing a five stage MAMuG (Multiaperture, Multigrid) accelerator. In this paper, the extension of the gap length, which is required to improve the voltage holding capability, is examined in two dimensional beam optics analyses and also from view point of stripping loss of ions. In order to suppress excess power loadings due to the direct interception of negative ions, which is issued in long pulse tests, the beamlet deflection is analyzed in three dimensional multibeamlet analyses. The necessary modifications shown above are applied to the MAMuG accelerator for coming long pulse tests in JAEA and ITER. PMID:20192419

Kashiwagi, M; Taniguchi, M; Dairaku, M; Grisham, L R; Hanada, M; Mizuno, T; Tobari, H; Umeda, N; Watanabe, K; Sakamoto, K; Inoue, T

2010-02-01

32

The main microwave components of the LHCD system for ITER  

Microsoft Academic Search

This paper outlines the preliminary radiofrequency analysis of the prominent microwave components of the LHCD system for ITER. The general overview and inclusive analysis of the system is given in Ph. Bibet et al. (Overview of the ITER-Feat LH System; this Conference), a companion paper in this Conference. The results of the analysis and optimisation of the most relevant components

F. Mirizzi; Ph. Bibet; S. Kuzikov

2003-01-01

33

Overview of ITER magnet system and European contribution  

Microsoft Academic Search

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

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

34

Risk analysis of the ITER cryogenic system  

NASA Astrophysics Data System (ADS)

The reliability of the ITER tokamak will strongly depend on the safe operation of the cryogenic system. The objective of the performed risk analysis is to identify all the possible risks to personnel, equipment and environment resulting from cryogenic system failures that might accidentally occur within any phases of the machine operation, and that could not be eliminated by design. The applied methodology of the presented risk analysis is based on the Failure Mode and Effects Analysis. All the potential failure modes were analyzed to identify their possible effects and then to classify them according to their severity and probability of occurrence. The Pareto-Lorentz analysis has been used for ranking all the identified failures and determining the most credible incidents and scenarios. For the most credible scenarios numerical simulations of the helium outflows from the system have been performed, including analysis of the helium flow impact on the neighboring confinements. Conclusions concerning the system safe operation, remedial actions and mitigations of the most credible incidents have been formulated.

Chorowski, Maciej; Fydrych, Jaroslaw; Grabowski, Maciej; Serio, Luigi

2012-06-01

35

ITER power and particle control system  

SciTech Connect

The ITER power and particle control system is designed to exhaust the 300 to 400 MW of alpha and auxiliary heating power and the 5 x 10{sup 20} He atoms per second created by the fusion reactions, to control the density and to fuel the plasma. The power and particle control system consists of a single null poloidal divertor, a set of active pumps with a total pumping speed of approx. 200 m{sup 3}/s, and gas puffing and pellet fuelling systems. Atomic processes are used to spread out the heating power over the first wall and divertor walls, thereby reducing the peak heat loads on the divertor plates to acceptable levels. The divertor has a `vertical target` plate configuration and tight baffling to maximize the effectiveness of the atomic processes for energy losses in the divertor and to maximize the neutral pressure in the divertor and minimize the backflow of neutrals from the divertor to the main chamber. 14 refs., 9 figs., 1 tab.

Post, D.; Ando, T.; Antipenkov, A. [Max Plank Inst. for Plasma Physics, Garching (Germany)] [and others

1996-12-31

36

ITER neutral beam system US conceptual design  

SciTech Connect

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.

Purgalis, P.

1990-09-01

37

Conference on iterative methods for large linear systems  

SciTech Connect

This conference is dedicated to providing an overview of the state of the art in the use of iterative methods for solving sparse linear systems with an eye to contributions of the past, present and future. The emphasis is on identifying current and future research directions in the mainstream of modern scientific computing. Recently, the use of iterative methods for solving linear systems has experienced a resurgence of activity as scientists attach extremely complicated three-dimensional problems using vector and parallel supercomputers. Many research advances in the development of iterative methods for high-speed computers over the past forty years are reviewed, as well as focusing on current research.

Kincaid, D.R. [comp.

1988-12-01

38

Neutronics analysis of the ITER NB system  

Microsoft Academic Search

Neutronics of the neutral beam (NB) injector for international thermonuclear experimental reactors (ITER) was analyzed by two- and three-dimension (3-D) codes, and their results were then compared. The neutron flux on the beam line axis obtained by the 2-D code agrees with that by the 3-D code within 30%. The shutdown dose rate around the NB injector was estimated by

K Shibata; K Maki; T Inoue; M Hanada; Y Okumura; Y Yamashita

2000-01-01

39

Radiation analysis of the ITER pellet injection system  

Microsoft Academic Search

The results of neutronics calculations for the pellet injection system of the International Thermonuclear Experimental Reactor (ITER) are described. Hands-on maintenance of components in the pellet injection room results in a considerable simplification of maintenance support equipment and in greater system availability. The basic configuration of the pellet injection system includes small-diameter guide tubes with which the pellet may have

M. J. Gouge; I. C. Gomes; L. T. Gomes; P. N Stevens

1991-01-01

40

Engineering Design of ITER Prototype Fast Plant System Controller  

Microsoft Academic Search

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

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

41

Multilevel iteration for mixed finite element systems with penalty  

Microsoft Academic Search

In this paper, the authors consider the solution of the discrete systems that arises when a mixed finite element approach is used to approximate the solution of second-order elliptic boundary value problems. By the introduction of a penalty parameter, these equations can be approximated by the solution of a symmetric and positive definite penalty system on the velocity subspace. Iterative

Zhiqiang Cai; Charles I. Goldstein; Joseph E. Pasciak

1993-01-01

42

Design of fast tuning elements for the ITER ICH system  

SciTech Connect

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.

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

1996-05-01

43

An Iterative Jackknife Approach for Assessing Reliability and Power of fMRI Group Analyses  

PubMed Central

For functional magnetic resonance imaging (fMRI) group activation maps, so-called second-level random effect approaches are commonly used, which are intended to be generalizable to the population as a whole. However, reliability of a certain activation focus as a function of group composition or group size cannot directly be deduced from such maps. This question is of particular relevance when examining smaller groups (<20–27 subjects). The approach presented here tries to address this issue by iteratively excluding each subject from a group study and presenting the overlap of the resulting (reduced) second-level maps in a group percent overlap map. This allows to judge where activation is reliable even upon excluding one, two, or three (or more) subjects, thereby also demonstrating the inherent variability that is still present in second-level analyses. Moreover, when progressively decreasing group size, foci of activation will become smaller and/or disappear; hence, the group size at which a given activation disappears can be considered to reflect the power necessary to detect this particular activation. Systematically exploiting this effect allows to rank clusters according to their observable effect size. The approach is tested using different scenarios from a recent fMRI study (children performing a “dual-use” fMRI task, n?=?39), and the implications of this approach are discussed.

Wilke, Marko

2012-01-01

44

Status of the ITER ICRF system design - 'Externally Matched' approach  

SciTech Connect

The design of the ITER ICRF system has been under revision for several years. The paper presents the status of the design proposal based on a 24 strap antenna plug (6 poloidal by 4 toroidal short radiating conductors) in which the straps are passively combined in 8 poloidal triplets by means of 4-port junctions. These triplets are connected in parallel pairwise through matching elements to form 4 load-resilient conjugate-T circuits. All adjustable matching elements are located outside the plug, i.e. in the ITER port cell and in the generator area.

Lamalle, P. U.; Dumortier, P.; Durodie, F.; Evrard, M.; Louche, F.; Messiaen, A.; Vervier, M. [Laboratory for Plasma Physics, Association EURATOM-Belgian State, Royal Military Academy, B-1000 Brussels (Belgium); Shannon, M.; Borthwick, A.; Chuilon, B.; Nightingale, M. [UKAEA/EURATOM Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Brons, S. [FOM IPP Rijnhuizen, Association EURATOM-FOM, The Netherlands (Netherlands); Goulding, R.; Swain, D. [Oak Ridge National Laboratory, TN 37831-6169, Tennessee, USA. Partners in TEC (United States)

2007-09-28

45

On the equivalence of homogeneous iterated function systems  

NASA Astrophysics Data System (ADS)

We characterize the family { G}_F of homogeneous iterated function systems of similarities on {R}^d that satisfy the strong separation condition and generate the same self-similar set F. We also show that { G}_F as a semigroup is finitely generated.

Deng, Qi-Rong; Lau, Ka-Sing

2013-10-01

46

Harmonic analysis of iterated function systems with overlap  

Microsoft Academic Search

An iterated function system (IFS) is a system of contractive mappings taui:Y-->Y, i=1,...,N (finite), where Y is a complete metric space. Every such IFS has a unique (up to scale) equilibrium measure (also called the Hutchinson measure mu), and we study the Hilbert space L2(mu). In this paper we extend previous work on IFSs without overlap. Our method involves systems

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

2007-01-01

47

Numerical simulations of systems of PDEs by variational iteration method  

NASA Astrophysics Data System (ADS)

In this Letter, a general framework of the variational iteration method (VIM) is presented for solving systems of linear and nonlinear partial differential equations (PDEs). In VIM, a correction functional is constructed by a general Lagrange's multiplier which can be identified via a variational theory. VIM yields an approximate solution in the form of a rapid convergent series. Comparison with the exact solutions shows that VIM is a powerful method for the solution of linear and nonlinear systems of PDEs.

Batiha, B.; Noorani, M. S. M.; Hashim, I.; Batiha, K.

2008-02-01

48

Failure Mode and Effect Analysis for remote handling transfer systems of ITER  

Microsoft Academic Search

A Failure Mode and Effect Analysis (FMEA) at component level was done to study safety-relevant implications arising from possible failures in performing remote handling (RH) operations at ITER facility [1].Autonomous air cushion transporter, pallet, sealed casks and tractor movers needed for port plug mounting\\/dismantling operation were analysed. For each sub-system, the breakdown of significant components was outlined and, for each

T. Pinna; R. Caporali; A. Tesini

2008-01-01

49

Dynamic simulation of a proposed ITER tritium processing system  

SciTech Connect

Dynamically simulating the fuel cycle in a fusion reactor is crucial to developing a better understanding of the safe and reliable operation of this complex system. In this work, we propose a tritium processing system for ITER`s plasma exhaust. The dynamic simulation of this proposed system is then performed with the TRUFFLES (TRitiUm Fusion Fuel cycLE dynamic Simulation) model. The fuel management, storage, and fueling operations are developed and coupled with previous cryopump and fuel cleanup unit subsystems to fully realize the complete torus exhaust flow cycle. Results show that tritium inventories will vary widely depending upon reactor operation, individual subsystem and unit operation designs. A diverse collection of batch-controlled subsystems with changes in their processing parameters are simulated in this work. In particular, the effects from the fuel management subsystem`s fuel reserve and tank switching times are quantified using sensitivity studies. 6 refs., 10 figs., 2 tabs.

Kuan, W.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Scott W.R. [Los Alamos National Lab., NM (United States)

1995-10-01

50

ENVIRONMENTAL QUALITY INFORMATION SYSTEM - EQULS® - ITER  

EPA Science Inventory

This project consisted of an evaluation of the Environmental Quality Information System (EQuIS) software designed by Earthsoft, Inc. as an environmental data management and analysis platform for monitoring and remediation projects. In consultation with the EQuIS vendor, six pri...

51

Iterative approximation of k -limited polling systems  

Microsoft Academic Search

The present paper deals with the problem of calculating queue length distributions in a polling model with (exhaustive) limited service under the assumption of general arrival, service and setup distributions. The interest for this model is fueled by an application in the field of lo- gistics. Knowledge of the queue length distributions is needed to operate the system properly. The

M. Van Vuuren; Erik M. M. Winands

2007-01-01

52

Development of the ITER ICH Transmission Line and Matching System  

NASA Astrophysics Data System (ADS)

The ITER Ion Cyclotron Heating (ICH) System is designed to couple 20 MW of heating power for ion and electron heating. Prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system are being designed and tested. The ICH transmission lines are pressurized 300 mm diameter coaxial lines with water-cooled aluminum outer conductor and gas-cooled and water-cooled copper inner conductor. Each ICH transmission line is designed to handle 40- 55 MHz power at up to 6 MW/line. A total of 8 lines split to 16 antenna inputs on two ICH antennas. Industrial suppliers have designed coaxial transmission line and matching components and prototypes will be manufactured. The prototype components will be qualified on a test stand operating at the full power and pulse length needed for ITER. The matching system must accommodated dynamic changes in the plasma loading due to ELMS and the L to H-mode transition. Passive ELM tolerance will be performed using hybrid couplers and loads, which can absorb the transient reflected power. The system is also designed to compensate for the mutual inductances of the antenna current straps to limit the peak voltages on the antenna array elements.

Rasmussen, D. A.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Swain, D. W.; Fredd, E. H.; Hosea, J.; Greenough, N.

2011-11-01

53

Overview of the ITER-FEAT LH system  

Microsoft Academic Search

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

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

2003-01-01

54

Monitoring a Multi-Agent System Evolution through Iterative Development  

Microsoft Academic Search

\\u000a Iterative development is a well know project management technique which has notably been popularized in object-oriented development\\u000a through the use of the Rational Unified Process. Such an approach is nevertheless always driven by milestones rules on requirements\\u000a or design models while it could be applied onto the evolution of a Multi-Agent System (MAS) among the software project. We\\u000a propose in

Yves Wautelet; Manuel Kolp

2010-01-01

55

Iterated Function Systems and the Global Construction of Fractals  

Microsoft Academic Search

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

M. F. Barnsley; S. Demko

1985-01-01

56

Iterated function systems, Ruelle operators, and invariant projective measures  

Microsoft Academic Search

We introduce an harmonic analysis for iterated function systems (IFS) (X, mu)\\u000awhich is based on a Markov process on certain paths. The probabilities are\\u000adetermined by a weight function W on X. From W we define a transition operator\\u000aR_W acting on functions on X, and a corresponding class of R_W-harmonic\\u000afunctions. The properties of these functions determine the

Dorin Ervin Dutkay; Palle E. T. Jorgensen

2006-01-01

57

Design of an iterative receiver for linearly precoded MIMO systems  

Microsoft Academic Search

This paper presents an architecture design and implementation of an iterative receiver for linearly precoded MIMO systems. The receiver is composed of two main elements: an MMSE-IC equalizer and a 64-state MAX-LOG-MAP decoder which exchange soft information through an interleaving scheme. Each block of the architecture was designed to reach a trade off between complexity and error rate performance. Our

Daoud Karakolah; Christophe Jego; Charlotte Langlais; Michel Jezequel

2009-01-01

58

Progress on radio frequency auxiliary heating system designs in ITER  

SciTech Connect

ITER will require over 100 MW of auxiliary power for heating, on- and off-axis current drive, accessing the H-mode, and plasma shut-down. The Electron Cyclotron Range of Frequencies (ECRF) and Ion Cyclotron Range of Frequencies (ICRF) are two forms of Radio Frequency (RF) auxiliary power being developed for these applications. Design concepts for both the ECRF and ICRF systems are presented, key features and critical design issues are discussed, and projected performances outlined.

Makowski, M.; Bosia, G.; Elio, F.

1996-09-01

59

ITER prototype fast plant system controller based on ATCA platform  

Microsoft Academic Search

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

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

60

Radiation analysis of the ITER pellet injection system  

SciTech Connect

The results of neutronics calculations for the pellet injection system of the International Thermonuclear Experimental Reactor (ITER) are described. Hands-on maintenance of components in the pellet injection room results in a considerable simplification of maintenance support equipment and in greater system availability. The basic configuration of the pellet injection system includes small-diameter guide tubes with which the pellet may have several small-angle collisions before reaching the plasma. The pellet injector port through which the guide tubes pass will be shared with ITER plasma diagnostics, so the calculation takes into account penetrations to accommodate numerous channels for a neutron spectrometer and neutron and gamma-ray cameras. The conservative assumption of steady-state operation of ITER for 1000 days was taken as the baseline for calculating the activation of components in the pellet injection room. The plasma configuration is based on the current ITER guidelines, the first wall configuration is based on the most recently updated configuration, and the blanket configuration is based on the US proposal for the blanket. The plasma, coils, and blanket regions were analyzed with the Monte Carlo code MCNP. The transport of neutrons through the penetrations was also performed with MCNP. The pellet injection room was modeled with the two-dimensional discrete ordinates code DORT, which was also used for the transport of neutrons during operation and of gamma rays caused by activation. The activation calculations were carried out with the REBATE code. Results from this study indicate that restricted personnel access to the pellet injection room is possible, so limited hands-on maintenance can be performed on the majority of the components in the room.

Gouge, M.J. (Oak Ridge National Lab., TN (USA)); Gomes, I.C.; Gomes, L.T.; Stevens, P.N, (Tennessee Univ., Knoxville, TN (USA))

1991-03-01

61

Conceptual design Fusion Experimental Reactor (FER/ITER). Lower Hybrid Wave system.  

National Technical Information Service (NTIS)

This report describes a conceptual design of Lower Hybrid Wave (LH) system for FER and ITER. In JAERI, the conceptual design of LH system for FER has been performed in these 3 years in parallel to that of ITER. There must be a common design part with ITER...

K. Uehara T. Nagashima Y. Ikeda

1991-01-01

62

Transportation systems analyses, volume 2  

NASA Astrophysics Data System (ADS)

The principal objective is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military, and commercial payloads. The performance entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. Conceptual studies of transportation elements contribute to the systems approach by identifying elements (such as ETO node and transfer/excursion vehicles) needed in current and planned transportation systems. These studies are also a mechanism to integrate the results of relevant parallel studies.

1992-11-01

63

Operation mode studies of the ITER cryodistribution system  

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

64

Process Flow and Functional Analysis of the Iter Cryogenic System  

NASA Astrophysics Data System (ADS)

The ITER cryogenic system is presently under design by a large international collaboration. It will start commissioning at Cadarache, south of France in 2015. The system is designed to provide an equivalent refrigeration capacity of 65 kW at 4.5 K for the superconducting magnet and 1300 kW at 80 K for the cryoplant pre-cooling stages and the Cryostat Thermal Shields (CTS). The cryoplant consists of three 4.5 K refrigerators and two 80 K helium loops coupled with two LN2 modules. Two 4.5 K modules are dedicated to the magnet system and a small one is devoted to the cryopumps and Pellet Injection System. One Interconnection box interfaces the cryoplant and a complex cryodistribution system which includes 5 Auxiliary Cold Boxes dedicated to each cryogenic subsystem. The ITER cryogenic system will have to cope with various normal and abnormal operational modes including superconducting magnets quench recovery and fast energy discharge. We will present the general Process Flow Diagram of the cryoplant and cryodistribution system and the operation requirements. The functional analysis of the cryogenic system will be performed leading to a proposal of the cryogenic control system architecture. The instrumentation and control requirements will also be outlined.

Henry, D.; Chalifour, M.; Forgeas, A.; Kalinin, V.; Monneret, E.; Serio, L.; Vincent, G.; Voigt, T.

2010-04-01

65

ITER magnets.  

National Technical Information Service (NTIS)

As part of the summary of the Conceptual Design Activities (CDA) for the International Thermonuclear Experimental Reactor (ITER), this document describes the magnet systems for ITER, including the Toroidal Field (TF) and Poloidal Field (PF) Magnets, the S...

L. Bottura M. Hasegawa J. Heim

1991-01-01

66

Analysis of the ITER LFS Reflectometer Transmission Line System  

SciTech Connect

A critical issue in the design of the ITER Low Field Side (LFS) reflectometer is the transmission line (TL) system. A TL connects each launcher to a diagnostic instrument. Each TL will typically consist of ~42 m of corrugated waveguide and up to 10 miter bends. Important issues for the performance of the TL system are mode conversion and reflections. Minimizing mode conversion and reflections in the waveguide are critical to minimizing standing waves and phase errors in the reflectometer-measured phase. The performance of the corrugated waveguide and miter bends is analyzed and recommendations given.

Hanson, Gregory R [ORNL; Wilgen, John B [ORNL; Bigelow, Tim S [ORNL; Diem, Stephanie J [ORNL; Biewer, Theodore M [ORNL

2010-01-01

67

Rigidity of multi-dimensional conformal iterated function systems  

NASA Astrophysics Data System (ADS)

This paper starts with an appropriate version of the bounded distortion theorem. We show that for a regular iterated function system of countably many conformal contractions of an open connected subset of a Euclidean space ?3, satisfying the `open set condition', the Radon-Nikodym derivative dµ/dm has a real-analytic extension on an open neighbourhood of the limit set of this system, where m is the conformal measure and µ is the unique probability invariant measure equivalent with m. Next, within this context we explore the concept of the essential affinity of iterated function systems providing the several necessary and sufficient conditions. We prove the following rigidity result. If d?3 and h, a topological conjugacy between two not essentially affine systems F and G sends the conformal measure mF to a measure equivalent with the conformal measure mG, then h has a conformal extension on an open neighbourhood of the limit set of the system F. Finally, in exactly the same way as in Mauldin et al (2001 Compos. Math. to appear) we extend our rigidity result to the case of parabolic systems.

Urbanski, Mariusz

2001-11-01

68

Polychromator for the edge Thomson scattering system in ITER.  

PubMed

A new type polychromator has been designed for the edge Thomson scattering system in ITER. Signal light is parallelly dispersed into two parts at the first interference filter. Spectral transmissivities for some spectral channels may enhance better than the conventional type polychromator. In the new type polychromator, the misalignment due to the machine accuracy is expected to be within the margin of APD area. In order to calibrate the spectral transmissivity using the dual-laser injection method during the plasma discharge, it is preferred that the spectral channels are separated at the geometric mean of the injected two wavelengths. PMID:23126986

Yatsuka, E; Hatae, T; Fujie, D; Kurokawa, A; Kusama, Y

2012-10-01

69

Polychromator for the edge Thomson scattering system in ITER  

NASA Astrophysics Data System (ADS)

A new type polychromator has been designed for the edge Thomson scattering system in ITER. Signal light is parallelly dispersed into two parts at the first interference filter. Spectral transmissivities for some spectral channels may enhance better than the conventional type polychromator. In the new type polychromator, the misalignment due to the machine accuracy is expected to be within the margin of APD area. In order to calibrate the spectral transmissivity using the dual-laser injection method during the plasma discharge, it is preferred that the spectral channels are separated at the geometric mean of the injected two wavelengths.

Yatsuka, E.; Hatae, T.; Fujie, D.; Kurokawa, A.; Kusama, Y.

2012-10-01

70

ITER ICH Transmission Line and Matching System Prototype Development  

NASA Astrophysics Data System (ADS)

Design and testing of prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system is underway. Each ICH transmission line is designed to handle up to 6 MW/line in the 40-55 MHz frequency range. A total of 8 lines split to 16 antenna inputs on two ICH antennas. The ICH system is made up of 14 types of unique coaxial transmission line and matching components. The matching system is designed to provide passive ELM tolerance through the use of hybrid couplers and loads, which can absorb the transient reflected power. In addition the system is designed to compensate for coupling between antenna inputs caused by the mutual inductances of the current straps. It is further designed to balance as much as reasonable, the power requirements from the sources and the peak voltages on the antenna array elements.

Rasmussen, D. A.; Swain, D. W.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Fredd, E. H.; Hosea, J.; Greenough, N.

2011-12-01

71

Efficient Iterative Solution of Large Linear Systems on Heterogeneous Computing Systems  

Microsoft Academic Search

This dissertation deals mainly with the design, implementation, and analysis of efficient iterative\\u000asolution methods for large sparse linear systems on distributed and heterogeneous computing\\u000asystems as found in Grid computing.\\u000a\\u000aFirst, a case study is performed on iteratively solving large symmetric linear systems on\\u000aboth a multi–cluster and a local heterogeneous cluster using standard block Jacobi precondi-\\u000ationing within

T. P. Collignon

2011-01-01

72

Chevron beam dump for ITER edge Thomson scattering system.  

PubMed

This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due to nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated. PMID:24182106

Yatsuka, E; Hatae, T; Vayakis, G; Bassan, M; Itami, K

2013-10-01

73

Conceptual design of ACB-CP for ITER cryogenic system  

NASA Astrophysics Data System (ADS)

ACB-CP (Auxiliary Cold Box for Cryopumps) is used to supply the cryopumps system with necessary cryogen in ITER (International Thermonuclear Experimental Reactor) cryogenic distribution system. The conceptual design of ACB-CP contains thermo-hydraulic analysis, 3D structure design and strength checking. Through the thermohydraulic analysis, the main specifications of process valves, pressure safety valves, pipes, heat exchangers can be decided. During the 3D structure design process, vacuum requirement, adiabatic requirement, assembly constraints and maintenance requirement have been considered to arrange the pipes, valves and other components. The strength checking has been performed to crosscheck if the 3D design meets the strength requirements for the ACB-CP.

Jiang, Yongcheng; Xiong, Lianyou; Peng, Nan; Tang, Jiancheng; Liu, Liqiang; Zhang, Liang

2012-06-01

74

Harmonic analysis of iterated function systems with overlap  

NASA Astrophysics Data System (ADS)

An iterated function system (IFS) is a system of contractive mappings ?i:Y-->Y, i=1,...,N (finite), where Y is a complete metric space. Every such IFS has a unique (up to scale) equilibrium measure (also called the Hutchinson measure ?), and we study the Hilbert space L2(?). 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. These Cuntz-like operator systems were used in recent papers on wavelet analysis by Baggett, Jorgensen, Merrill, and Packer [Contemp. Math. 345, 11-25 (2004)], where they serve as a first step to generating wavelet bases of Parseval type (alias normalized tight frames), i.e., wavelet bases with redundancy. Similarly, it was shown in work by Dutkay and Jorgensen [Rev. Mat. Iberoam. 22, 131-180 (2006)] that the iterative operator approach works well for generating wavelets on fractals from IFSs without overlap. But so far the more general and more difficult case of essential overlap has resisted previous attempts at a harmonic analysis and explicit basis constructions, in particular. The operators generating the appropriate Cuntz relations are composition operators, e.g., Fi:f-->f??i, where (?i) is the given IFS. If the particular IFS is essentially nonoverlapping, it is relatively easy to compute the adjoint operators Si=Fi*, and the Si operators will be isometries in L2(?) with orthogonal ranges. For the case of essential overlap, we can use the extra terms entering in the computation of the operators Fi* as a ``measure'' of the essential overlap for the particular IFS we study. Here the adjoint operators Fi* refer to the Hilbert space L2(?), where ? is the equilibrium measure ? for the given IFS (?i).

Jorgensen, Palle E. T.; Kornelson, Keri; Shuman, Karen

2007-08-01

75

Design considerations for ITER (International Thermonuclear Experimental Reactor) magnet systems: Revision 1  

SciTech Connect

The International Thermonuclear Experimental Reactor (ITER) is now completing a definition phase as a beginning of a three-year design effort. Preliminary parameters for the superconducting magnet system have been established to guide further and more detailed design work. Radiation tolerance of the superconductors and insulators has been of prime importance, since it sets requirements for the neutron-shield dimension and sensitively influences reactor size. The major levels of mechanical stress in the structure appear in the cases of the inboard legs of the toroidal-field (TF) coils. The cases of the poloidal-field (PF) coils must be made thin or segmented to minimize eddy current heating during inductive plasma operation. As a result, the winding packs of both the TF and PF coils includes significant fractions of steel. The TF winding pack provides support against in-plane separating loads but offers little support against out-of-plane loads, unless shear-bonding of the conductors can be maintained. The removal of heat due to nuclear and ac loads has not been a fundamental limit to design, but certainly has non-negligible economic consequences. We present here preliminary ITER magnet systems design parameters taken from trade studies, designs, and analyses performed by the Home Teams of the four ITER participants, by the ITER Magnet Design Unit in Garching, and by other participants at workshops organized by the Magnet Design Unit. The work presented here reflects the efforts of many, but the responsibility for the opinions expressed is the authors'. 4 refs., 3 figs., 4 tabs.

Henning, C.D.; Miller, J.R.

1988-10-09

76

R&D and design for the cryogenic and mechanical vacuum pumping systems of ITER  

Microsoft Academic Search

The next generation thermonuclear fusion machine ITER comprises large cryogenic pumping systems to process very high gas throughputs. The paper starts from a summary of the requirements for the torus exhaust pumping system and the neutral beam injection system for plasma heating and discusses the design solutions derived to match them. All ITER force-cooled cryopumps are based on a modular

Chr. Day; A. Antipenkov; M. Dremel; H. Haas; V. Hauer; A. Mack; D. K. Murdoch; M. Wykes

2007-01-01

77

Iterative path integral calculation of quantum correlation functions for dissipative systems  

Microsoft Academic Search

An iterative path integral procedure is developed for calculating equilibrium two-time correlation functions of quantum dissipative systems. Its numerical feasibility is demonstrated by studying the position–position correlation function of two-level systems at various temperatures. It is also shown that canonical partition functions are also amenable to an iterative treatment.

Jiushu Shao; Nancy Makri

2001-01-01

78

The ITER divertor Thomson scattering system: engineering and advanced hardware solutions  

Microsoft Academic Search

A divertor Thomson scattering (TS) system being developed for ITER has incorporated proven solutions from currently available TS systems. On the other hand any ITER diagnostic has to operate in a hostile environment and very restricted access geometry. Therefore the operation in an environment of intensive stray light, plasma background radiation, the necessity meet the requirement using only a 20

E E Mukhin; V V Semenov; A G Razdobarin; S Yu Tolstyakov; M M Kochergin; G S Kurskiev; A A Berezutsky; K A Podushnikova; S V Masyukevich; P V Chernakov; A I Borovkov; V S Modestov; A S Nemov; A S Voinov; A F Kornev; V K Stupnikov; A A Borisov; G N Baranov; A N Koval; A F Makushina; B A Yelizarov; A S Kukushkin; A Encheva; P Andrew

2012-01-01

79

Identification methods for Wiener nonlinear systems based on the least squares and gradient iterations  

Microsoft Academic Search

This paper derives a least squares based and a gradient based iterative identification algorithms for Wiener nonlinear systems. These methods separate one bilinear-parameter cost function into two linear-parameter cost functions, estimating directly the parameters of the Wiener systems. The simulation results confirm that the proposed two algorithms are valid and the least squares based iterative algorithm has faster convergence rates

Dongqing Wang; Yanyun Chu; Feng Ding

2009-01-01

80

Analysis of the ITER ICRH Decoupling and Matching System  

SciTech Connect

The reference ITER ICRH load resilient matching system uses four 3dB hybrid power splitters. It is proposed to use a 'double stub' tuner (DST) configuration for the matching on the reference load and a decoupling system placed between the antenna plug and the matching system to reduce the mutual coupling effects and also to actively control the array current spectrum while requesting the same forward power from all 4 power sources. The paper analyzes (i) the optimization of the matching layout e.g. by varying the distance between the stubs and by the use of two capacitors taking into account the role of the decouplers on the matching requirements; (ii) the practical realization of the decouplers and their insertion into the circuit; (iii) the requests in voltage and current capabilities in the different parts of the system. The paper presents solutions for saving space and to decrease the ratings of the components. The computations are done with the array loading simulated by the TOPICA matrix.

Vervier, M.; Messiaen, A.; Dumortier, P. [Plasma Physics Laboratory, Royal Military Academy, Brussels, Belgium, TEC Partner (Belgium)

2009-11-26

81

An overview of control system for the ITER electron cyclotron system  

Microsoft Academic Search

The ITER electron cyclotron (EC) system having capability of up to 26MW generated power at 170GHz is being procured by 5 domestic agencies via 10 procurement arrangements. This implies diverse types of equipment and complex interface management. It also places a challenge on control system architecture to entertain the constraints of procurement slicing and meeting the overall functional requirement. The

D. Purohit; T. Bigelow; D. Billava; T. Bonicelli; J. Caughman; C. Darbos; G. Denisov; F. Gandini; T. Gassmann; M. Henderson; J. Y. Journeux; K. Kajiwara; N. Kobayashi; C. Nazare; Y. Oda; T. Omori; S. L. Rao; D. Rasmussen; D. Ronden; G. Saibene; K. Sakamoto; F. Sartori; K. Takahashi; R. Temkin

2011-01-01

82

On modified block SSOR iteration methods for linear systems from steady incompressible viscous flow problems  

Microsoft Academic Search

In order to solve the large sparse systems of linear equations arising from numerical solutions of two-dimensional steady incompressible viscous flow problems in primitive variable formulation, we present block SSOR and modified block SSOR iteration methods based on the special structures of the coefficient matrices. In each step of the block SSOR iteration, we employ the block LU factorization to

Yu-Hong Ran; Li Yuan

2010-01-01

83

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

Microsoft Academic Search

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

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

2006-01-01

84

ITER neutral beam system US conceptual design. Final vesion  

SciTech Connect

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.

Purgalis, P.

1990-09-01

85

R&D progress of the high power negative ion accelerator for the ITER NB system at JAEA  

NASA Astrophysics Data System (ADS)

At JAEA, as the Japan Domestic Agency (JADA) for ITER, a MAMuG (multi-aperture multi-grid) accelerator has been developed to perform the required R&D for the ITER neutral beam (NB) system. As a result of countermeasures to handle excess heat load to the ion source by backstreaming positive ions, H- ion beam current was increased to 0.32 A (the ion current density of 140 A m-2) at a beam energy of 796 keV. This high power beam acceleration simulated the ITER operation condition maintaining the perveance (H- ion current density/beam energy3/2) of the ITER accelerator. After the high power beam operation, the pulse length was successfully extended from 0.2 to 5 s at 550 keV, which yielded a 131 mA H- ion beam as an initial test of the long pulse operation. A test of a single-aperture single-gap (SINGAP) accelerator was performed at JAEA under an ITER R&D task agreement. The objective of this test was to compare two different accelerator concepts (SINGAP and MAMuG) at the same test facility. As a result, the MAMuG accelerator was defined as the baseline design for ITER, due to advantages in its better voltage holding and less electron acceleration. In three-dimensional beam trajectory analyses, the aperture offset at the bottom of the extractor was found to be effective for compensation of beamlet deflection due to their own space charge. It has been analytically demonstrated that these compensated beamlets can be focused at a focal point by adopting the aperture offset at the final grid of the accelerator.

Kashiwagi, M.; Taniguchi, M.; Dairaku, M.; de Esch, H. P. L.; Grisham, L. R.; Svensson, L.; Tobari, H.; Umeda, N.; Watanabe, K.; Sakamoto, K.; Inoue, T.

2009-06-01

86

ITPACK 2C: A FORTRAN Package for Solving Large Sparse Linear Systems by Adaptive Accelerated Iterative Methods  

Microsoft Academic Search

ITPACK 2C is a collection of seven FORTRAN subroutines for solving large sparse linear systems by adaptive accelerated iterative algorithms. Basic iterative procedures, such as the Jacobi method, the Successive Overrelaxation method, the Symmetric Suc- cessive Overrelaxation method, and the RS method for the reduced system are com- bined, where possible, with acceleration procedures such as Chebyshev (Semi-Iteration) and Conjugate

David R. Kincaid; John R. Respess; David M. Young; Roger G. Grimes

1996-01-01

87

ITER ECH Transmission System Test Stand and Prototype Development  

Microsoft Academic Search

Progress in acquisition and testing of prototype components and developing a high power test stand will be described. The US ITER Project Office is responsible for providing the ECH transmission lines that are based on evacuated 63.5 mm diameter corrugated waveguide. Each line is designed to handle 170 GHz power at 1 MW and possibly up to 2 MW in

T. S. Bigelow; J. B. Caughman; D. A. Rasmussen; T. E. Whittle; M. A. Shapiro; J. R. Sirigiri; R. J. Temkin

2009-01-01

88

Active spectroscopic measurements using the ITER diagnostic system  

SciTech Connect

Active (beam-based) spectroscopic measurements are intended to provide a number of crucial parameters for the ITER device being built in Cadarache, France. These measurements include the determination of impurity ion temperatures, absolute densities, and velocity profiles, as well as the determination of the plasma current density profile. Because ITER will be the first experiment to study long timescale ({approx}1 h) fusion burn plasmas, of particular interest is the ability to study the profile of the thermalized helium ash resulting from the slowing down and confinement of the fusion alphas. These measurements will utilize both the 1 MeV heating neutral beams and a dedicated 100 keV hydrogen diagnostic neutral beam. A number of separate instruments are being designed and built by several of the ITER partners to meet the different spectroscopic measurement needs and to provide the maximum physics information. In this paper, we describe the planned measurements, the intended diagnostic ensemble, and we will discuss specific physics and engineering challenges for these measurements in ITER.

Thomas, D. M. [ITER Organization, 13067 St. Paul-lez-Durance Cedex (France); Counsell, G. [Fusion for Energy, 08019 Barcelona (Spain); Johnson, D. [US ITER Project Office, Oak Ridge, Tennessee 37830 (United States); Vasu, P. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Zvonkov, A. [Russian Research Center ''Kurchatov Institute'', Moscow 123182 (Russian Federation)

2010-10-15

89

Biomarker Selection System, Employing an Iterative Peak Selection Method, for Identifying Biomarkers Related to Prostate Cancer  

Microsoft Academic Search

A biomarker selection system is proposed for identifying biomarkers related to prostate cancer. MS-spectra were obtained from\\u000a the National Cancer Institute Clinical Proteomics Database. The system comprised two stages, a pre-processing stage, which\\u000a is a sequence of MS-processing steps consisting of MS-spectrum smoothing, novel iterative peak selection, peak alignment,\\u000a and a classification stage employing the PNN classifier. The proposed iterative

Panagiotis Bougioukos; Dionisis Cavouras; Antonis Daskalakis; Ioannis Kalatzis; Spiros Kostopoulos; Pantelis Georgiadis; George Nikiforidis; Anastasios Bezerianos

2007-01-01

90

A cryogenic system design for the international thermonuclear experimental reactor (ITER)  

SciTech Connect

A conceptual design for ITER was completed last year. The author developed a suitable cryogenic system for ITER as part of this conceptual design effort. An overview of the design is reported. Emphasis is on the fact that cryogenics is a mature science, and a system supporting ITER needs can be made from time-proven components without loss of efficiency or reliability. Because of the large size of the ITER cryogenic system, large numbers of compressors and expanders must be used. Very high reliability is assured by arranging these components in parallel banks where servicing of individual components can be done without interruption of operations. This and other ideas based on the author's experience with Mirror Fusion Test Facility (MFTF) operations are described. 5 refs., 3 figs.

Slack, D.S.

1991-09-25

91

Development of a YAG laser system for the edge Thomson scattering system in ITER.  

PubMed

A prototype YAG laser system for the edge Thomson scattering system in ITER has been newly developed. Performance of the laser amplifier was improved by using flow tubes made of samarium-doped glass; the small signal gain reached 20 at its maximum. As a result, an output energy of 7.66 J at 100 Hz was successfully achieved, and the performance exceeded the target performance (5 J, 100 Hz). PMID:23127001

Hatae, T; Yatsuka, E; Hayashi, T; Yoshida, H; Ono, T; Kusama, Y

2012-10-01

92

Low Complexity Fano-Based Detection Algorithm with Iterative Structure for V-BLAST Systems  

NASA Astrophysics Data System (ADS)

We present a computationally efficient Fano detection algorithm with an iterative structure for V-BLAST systems. As our previous work, we introduced a Fano-based sequential detection scheme with three interrelated steps whose computational loads are excessive. To deal with the computational inefficiency, the proposed algorithm is redesigned by the addition of two steps: preparation and iterative tree searching. In particular, it employs an early stop technique to avoid the unnecessary iteration or to stop the needless searching process of the algorithm. Computer simulation shows that the proposed scheme yields significant saving in complexity with very small performance degradation, compared with sphere detection (SD).

Cha, Jongsub; Jeon, Hyoungsuk; Lee, Hyuckjae

93

A comparative study of iterative solutions to linear systems arising in quantum mechanics  

SciTech Connect

This study is mainly focused on iterative solutions with simple diagonal preconditioning to two complex-valued nonsymmetric systems of linear equations arising from a computational chemistry model problem proposed by Sherry Li of NERSC. Numerical experiments show the feasibility of iterative methods to some extent when applied to the problems and reveal the competitiveness of our recently proposed Lanczos biconjugate A-orthonormalization methods to other classic and popular iterative methods. By the way, experiment results also indicate that application specific preconditioners may be mandatory and required for accelerating convergence.

Jing Yanfei, E-mail: yanfeijing@uestc.edu.c [School of Mathematical Sciences/Institute of Computational Science, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731 (China); Huang Tingzhu, E-mail: tzhuang@uestc.edu.c [School of Mathematical Sciences/Institute of Computational Science, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731 (China); Duan Yong, E-mail: duanyong@yahoo.c [School of Mathematical Sciences/Institute of Computational Science, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731 (China); Carpentieri, Bruno, E-mail: b.carpentieri@rug.n [Institute of Mathematics and Computing Science, University of Groningen, Nijenborgh 9, P.O. Box 407, 9700 AK Groningen (Netherlands)

2010-11-01

94

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

SciTech Connect

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.

Joanny, M.; Salasca, S.; Dapena, M.; Cantone, B.; Travere, J. M. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Thellier, C.; Ferme, J. J. [THALES SESO, 13593 Aix-en-Provence Cedex 3 (France); Marot, L. [Department of Physics, University of Basel, 4056 Basel (Switzerland); Buravand, O. [Institut d'Optique Graduate School, 91127 Palaiseau (France); Perrollaz, G. [AMETRA, 13770 Venelles (France); Zeile, C. [INR, KIT, D-76344 Eggenstein-Leopoldshafen (Germany)

2012-10-15

95

Development of a Twin-Screw D-2 Extruder for the ITER Pellet Injection System  

Microsoft Academic Search

A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. The extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with single-stage gas gun into the plasma. A one-fifth ITER scale prototype extruder has been built to produce a continuous solid deuterium

Steven J Meitner; Larry R Baylor; Juan J Carbajo; Stephen Kirk Combs; Dan T Fehling; Charles R Foust; Marshall T McFee; James M McGill; David A Rasmussen; R G Sitterson; Dennis O Sparks; A L Qualls

2009-01-01

96

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

SciTech Connect

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.

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

2005-09-02

97

The multistage variational iteration method for a class of nonlinear system of ODEs  

NASA Astrophysics Data System (ADS)

This paper implements the multistage variational iteration method (MVIM) to solve a class of nonlinear system of first-order ordinary differential equations (ODEs). The domain of validity of the solutions via the standard variational iteration method (VIM) is extended by the simple multistage strategy. Comparisons with the exact solution and the fourth-order Runge-Kutta (RK4) method show that the MVIM is a reliable method for nonlinear equations.

Batiha, B.; Noorani, M. S. M.; Hashim, I.; Ismail, E. S.

2007-10-01

98

Automated Water Analyser Computer Supported System (AWACSS)  

Microsoft Academic Search

A novel analytical system AWACSS (Automated Water Analyser Computer Supported System) based on immunochemical technology has been evaluated that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration or pre-treatment steps.Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD)

Jens Tschmelak; Guenther Proll; Johannes Riedt; Joachim Kaiser; Peter Kraemmer; Luis Bárzaga; James S. Wilkinson; Ping Hua; J. Patrick Hole; Richard Nudd; Michael Jackson; Ram Abuknesha; Damià Barceló; Sara Rodriguez-Mozaz; Maria J. López de Alda; Frank Sacher; Jan Stien; Jaroslav Slobodník; Peter Oswald; Helena Kozmenko; Eva Korenková; Lívia Tóthová; Zoltan Krascsenits; Guenter Gauglitz

2005-01-01

99

Investigation of 'Conjugate T' Load-Resilient ICRF Antenna Systems - Application to the JET ITER-Like and to a Possible ITER ICRF System  

SciTech Connect

The paper reports on the radio-frequency (RF) analysis of multiple-short-strap load-resilient ICRF antenna systems, applied to the JET ITER-Like and to a proposed ITER ICRF system. The short radiating straps minimize the antenna voltage and the 'conjugate T' load resilient matching circuit aims at reliable power delivery to ELMy H mode plasmas. The two designs mainly differ by the use of in-vessel matching capacitors for the JET array, whereas the proposed ITER design uses an optimized combination of straps in parallel and ex-vessel matching by means of line stretchers. Asymmetries and mutual coupling between straps strongly influence the performance of such load-resilient circuits and complicate their operation. These effects have been analyzed in detail along two parallel lines of investigation: (i) Detailed RF simulations, in which the input impedance matrix of the ICRF arrays has been computed with a three-dimensional electromagnetic code and incorporated in realistic models of the transmission and matching circuits, (ii) Comprehensive RF measurements on a scaled-down mockup of the proposed ITER antenna. Ongoing work to optimize array performance and to develop practical matching procedures and reliable automatic control of the matching elements is discussed. The main outstanding issues are reliable arc detection and demonstration of a robust array control algorithm.

Lamalle, P.U.; Messiaen, A.M.; Dumortier, P.; Durodie, F.; Evrard, M.; Louche, F.; Vervier, M.; Weynants, R. [Laboratory for Plasma Physics, Association EURATOM - Belgian State, Partner in the Trilateral Euregio Cluster, Royal Military Academy, 30 av. de la Renaissance, B-1000 Brussels (Belgium)

2005-09-26

100

Non-iterative aberration correction of a multiple transmitter system.  

PubMed

Multi-transmitter aperture synthesis provides aperture gain and improves effective aperture fill factor by shifting the received speckle field through the use of multiple transmitter locations. It is proposed that by utilizing methods based on shearing interferometry some low-order aberrations, such as defocus, can be found directly rather than through iterative algorithms. The current work describes the theory behind multi-transmitter aberration correction and describes experiments used to validate this method. Experimental results are shown which demonstrate the ability of such a sensor to solve directly for defocus and toric curvature in the captured field values. PMID:22273896

Rabb, David J; Stafford, Jason W; Jameson, Douglas F

2011-12-01

101

Global ICRF system designs for ITER and TPX  

SciTech Connect

The design of feed networks for ICRF antenna arrays on ITER and TPX are discussed. Features which are present in one or both of the designs include distribution of power to several straps from a single generator, the capability to vary phases of the currents on antenna elements rapidly without the need to rematch, and passive elements which present a nearly constant load to the generators during ELM induced loading transients of a factor of I0 or more. The FDAC (Feedline/Decoupler/Antenna Calculator) network modeling code is described, which allows convenient modeling of the electrical performance of nearly arbitrary ICRF feed networks.

Goulding, R.H.; Hoffman, D.J.; Ryan, P.M. [Oak Ridge National Lab., TN (United States); Durodie, F. [Association Euratom, Brussels (Belgium)

1995-09-01

102

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

SciTech Connect

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.

Donato, J.M.

1993-08-01

103

Transportation systems analyses: Volume 1: Executive Summary  

NASA Astrophysics Data System (ADS)

The principal objective of this study is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. This executive summary of the transportation systems analyses (TSM) semi-annual report addresses the SSF logistics resupply. Our analysis parallels the ongoing NASA SSF redesign effort. Therefore, there could be no SSF design to drive our logistics analysis. Consequently, the analysis attempted to bound the reasonable SSF design possibilities (and the subsequent transportation implications). No other strategy really exists until after a final decision is rendered on the SSF configuration.

1993-05-01

104

Finding the optimal control of linear systems via He's variational iteration method  

Microsoft Academic Search

In this article, He's variational iteration method has been applied to find the optimal control of linear systems, approximately. Numerical results are given for several test examples involving scalar and second-order systems to demonstrate the applicability and efficiency of the method.

S. A. Yousefi; Mehdi Dehghan; A. Lotfi

2010-01-01

105

Informing the design of an information management system with iterative fieldwork  

Microsoft Academic Search

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

Victoria Bellotti; Ian Smith

2000-01-01

106

Design and overview of fabrication tests for the 1 MV bushing for ITER NB system  

Microsoft Academic Search

The ITER NB System consists of two injectors each delivering 16.7 MW to the plasma in the form of neutral deuterium atoms accelerated at 1 MeV. Each injector has a single negative ion source connected to a 1 MV electrostatic accelerator. The accelerated negative ions pass through a neutraliser, then an electrostatic deflection system, where residual ions, exiting after neutralisation,

E. Di Pietro; T. Amemiya; M. Hanada; T. Iga; T. Inoue; Y. Okumura; K. Watanabe

2003-01-01

107

Design of a cooling system for the ITER Ion Source and Neutral Beam test facilities  

Microsoft Academic Search

This paper deals with the requirements, operational modes and design of the cooling system for the ITER Neutral Beam test experiments. Different operating conditions of the experiments have been considered in order to identify the maximum heat loads that constitute, with the inlet temperature and pressure at each component, the design requirements for the cooling system.The test facility components will

M. Dalla Palma; S. Dal Bello; F. Fellin; P. Zaccaria

2009-01-01

108

Sequence coding based on the fractal theory of iterated tranformations systems  

Microsoft Academic Search

A new scheme for sequence coding based on the iterated functions systems theory is presented. The method relies on a 3D approach in which the sequence is adaptively partitioned. Each partition block can be coded either by using the spatial self similarities or by exploiting temporal redundancies. The proposed system shows very good performances when compared to other existing methods.

Emmanuel Reusens

1993-01-01

109

3D Monte Carlo vacuum modeling of the neutral beam injection system of ITER  

Microsoft Academic Search

ITER plans to implement several heating neutral beam injection (HNB) systems, which shoot the energetic neutral beams of hydrogen or deuterium atoms into the plasma. For efficient neutralization of the accelerated hydrogen or deuterium ions, a particular gas density profile along the beamline is required in the HNB system. A novel Monte Carlo simulation code has been developed which is

X. Luo; Chr. Day

2010-01-01

110

Generic control system design for the Cassette Multifunctional Mover and other ITER remote handling equipment  

Microsoft Academic Search

A new suite of Remote Handling (RH) equipment, addressing the latest design of the divertor region, is currently being specified for ITER, with procurement of the Cassette Multifunctional Mover (CMM) scheduled for 2005–2006. This presents a unique opportunity to address a vital component of the RH system – the control system – and this paper introduces a number of concepts

M. Irving; J. Palmer; M. Siuko

2005-01-01

111

Participatory Design of Large-Scale Information Systems A Reconstruction of the Iterative Prototyping Approach  

Microsoft Academic Search

In this article we discuss how to engage in large-scale information systems development by applying a participatory design (PD) approach that acknowledges the unique situated work practices conducted by the domain experts of modern organizations. We reconstruct the iterative prototyping approach into a PD process model that (1) emphasizes PD experiments as transcending traditional prototyping by evaluating fully integrated systems

Jesper Simonsen; Morten Hertzum

112

Steady state and dynamic simulation of the ITER hydrogen isotope separation system  

SciTech Connect

Steady state and dynamic simulation studies of the ITER Hydrogen Isotope Separation System (ISS) are presented. Ontario Hydro`s FLOSHFET code is used as the reference code for design studies of the ISS. Dynamic simulation are also carried out using Ontario Hydro`s DYNSIM code. The ITER ISS dynamic simulation is important because it allows study of product quality control schemes and control system design. It also allows accurate assessment of tritium inventory variation in different operating modes. The cryogenic distillation model in the new DYNSIM code is described including the underlying theory and numerical simulation approach. 9 refs., 3 figs.

Busigin, A. [NITEK Corp., London (Canada); Sood, S.K. [Ontario Hydro, Toronto (Canada)

1995-10-01

113

New Cryogenic Steels and Design Approach for ITER Superconducting Magnet System  

SciTech Connect

A new design code has been developed for construction and operation/maintenance of the International Thermonuclear Experimental Reactor (ITER). A superconducting magnet system is one of the key components of ITER and its design code includes new cryogenic materials and design approach with taking account of unique features of a performance of the superconducting magnet. The new materials are nitrogen strengthened austenitic stainless steels, which have a yield strength (S{sub y}) of over 1000 MPa and fracture toughness (KIc) of over 200 MP/m at liquid helium temperature (4 K). The feature of the design approach is use of the allowable stress defined by only 2/3 S{sub y} measured at 4 K A concept and reliability of the new design approach using new cryogenic materials for the ITER superconducting magnet system are discussed in this paper. (authors)

Nakajima, H.; Hamada, K.; Okuno, K.; Hada, K.; Tada, E. [Japan Atomic Energy Research Institute (Japan)

2002-07-01

114

Conceptual design of a High Temperature Superconductor current feeder system for ITER  

NASA Astrophysics Data System (ADS)

The International Thermonuclear Experimental Reactor (ITER) project envisages a techno-economically feasible solution of its current feeder system in order to reduce the overall cryogenic requirements and operational costs. Since the ITER magnet system has a long stand-by time with respect to its operation duty cycle, it is essential to optimize the operational costs of the current feeder system taking into consideration both, the full current and stand-by modes. The present HTS technology has reached the maturity that HTS conductors are applicable for the current feeder system of ITER. The replacement of the actually planned conventional current leads by HTS current leads would provide considerable savings in the refrigeration investment and operational costs. Another option is the substitution of the water cooled high current aluminum feeders by HTS feeders, so called HTS bus bars. In this paper, the different design options of Bi-2223/Ag HTS based bus bars as prototype unit modules for ITER are discussed. The performance of different cooling schemes for HTS bus bars is studied and the design related critical issues e.g. metallic transition (65 K -300 K) and bending of bus bar, AC loss, thermal loss and reliability of the cooling system are investigated.

Tanna, V. L.; Fietz, W. H.; Heller, R.; Vostner, A.; Wesche, R.; Zahn, G. R.

2006-06-01

115

Transportation systems analyses. Volume 1: Executive summary  

NASA Astrophysics Data System (ADS)

The principal objective is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform crew delivery and return, cargo transfer, cargo delivery and return, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include: the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationship between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. Conceptual studies of transportation elements contribute to the systems approach by identifying elements (such as ETO node and transfer/excursion vehicles) needed in current and planned transportation systems. These studies are also a mechanism to integrate the results of relevant parallel studies.

1992-11-01

116

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

NASA Astrophysics Data System (ADS)

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.

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

117

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

SciTech Connect

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 blanket exchange and divertor cassette replacement are planned. The metrology system must be compatible with the ITER in-vessel environment of high gamma radiation ({approximately} 10{sup 6} R/hr), super-clean ultra-high-vacuum ({approximately} 10{sup {minus}8} Torr), and elevated temperature ({approximately}200 C). A fast scanning rate is required since the plasma facing surface in ITER is very large ({approximately} 1,500 m{sup 2}). A coherent FM laser radar based metrology system, developed by Coleman Research Corporation, is being adopted to accomplish this task. Conceptually, this metrology system consists of a compact (few cm{sup 3}) remotely deployed laser transceiver optics module, linked through fiber optics to the laser source and imaging units that are located outside the biological shield. Range measurements conducted on a variety of surfaces using the system have yielded sub-millimeter accuracy. Therefore, the technique will easily meet the precision requirement for the ITER application. Computer simulations have been carried out to determine the optimum number of units required for complete mapping of the plasma facing surfaces. Most in-vessel components of the system appear to be radiation hardenable and vacuum compatible. Details of the system and developments required to make it fully compatible for ITER metrology application will be elaborated.

Barry, R.E.; Burgess, T.W.; Menon, M.M. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Slotwinski, A.; Sebastian, R. [Coleman Research Corp., Springfield, VA (United States)

1995-12-31

118

Twin-screw extruder development for the ITER pellet injection system  

Microsoft Academic Search

The ITER pellet injection system is comprised of devices to form and accelerate pellets, and will be connected to inner wall guide tubes for fueling, and outer wall guide tubes for ELM pacing. An extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with a gas gun into the plasma.

S. J. Meitner; L. R. Baylor; S. K. Combs; D. T. Fehling; J. M. McGill; D. A. Rasmussen; J. W. Leachman

2009-01-01

119

SUMMARIZED RESULTS OF THE CRYOSORPTION PANEL TEST PROGRAMME FOR THE ITER CRYOPUMPING SYSTEM  

Microsoft Academic Search

A reliable but versatile primary cryopumping system is required for high vacuum pumping of the ITER to- rus during all phases of plasma operation. To achieve that goal, an extensive R&D programme has been perform- ed within the framework of the Nuclear Fusion Project of FZK, supported by the European Communities under the European Fusion Technology Programme. The present paper

H. HAAS; N. T. KAZAKOVSKY; A. MACK; D. K. MURDOCH; D. RÖHRIG; G. L. SAKSAGANSKY; Forschungszentrum Karlsruhe; D. V. Efremov

120

Nonlinear focusing Manakov systems by variational iteration method and adomian decomposition method  

NASA Astrophysics Data System (ADS)

In this paper, the variational iteration method (VIM) and the Adomian decomposition method (ADM) are applied to solve numerically the focusing Manakov systems of coupled nonlinear Schrödinger equations. The accuracy of the methods are verified by ensuring that the conserved quantities remain almost constant. The results show that VIM is much easier, more convenient, more stable and efficient than ADM.

Sweilam, N. H.; Khader, M. M.; Al-Bar, R. F.

2008-02-01

121

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

Microsoft Academic Search

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

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

1995-01-01

122

Twin-Screw Extruder Development for the ITER Pellet Injection System  

SciTech Connect

The ITER pellet injection system is comprised of devices to form and accelerate pellets, and will be connected to inner wall guide tubes for fueling, and outer wall guide tubes for ELM pacing. An extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with a gas gun into the plasma. The ITER pellet injection system is required to provide a plasma fueling rate of 120 Pa-m3/s (900 mbar-L/s) and durations of up to 3000 s. The fueling pellets will be injected at a rate up to 10 Hz and pellets used to trigger ELMs will be injected at higher rates up to 20 Hz. A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. A one-fifth ITER scale prototype has been built and has demonstrated the production of a continuous solid deuterium extrusion. The 27 mm diameter, intermeshed, counter-rotating extruder screws are rotated at a rate up to ?5 rpm. Deuterium gas is pre-cooled and liquefied and solidified in separate extruder barrels. The precooler consists of a deuterium gas filled copper coil suspended in a separate stainless steel vessel containing liquid nitrogen. The liquefier is comprised of a copper barrel connected to a Cryomech AL330 cryocooler, which has a machined helical groove surrounded by a copper jacket, through which the pre-cooled deuterium condenses. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at ?15 K) before it is forced through the extruder die. The die forms the extrusion to a 3 mm x 4 mm rectangular cross section. Design improvements have been made to improve the pre-cooler and liquefier heat exchangers, to limit the loss of extrusion through gaps in the screws. This paper will describe the design improvements for the next iteration of the extruder prototype.

Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Leachman, J. W. [University of Wisconsin, Madison

2009-01-01

123

Cryogenic Viscous Compressor Development and Modeling for the ITER Vacuum System  

SciTech Connect

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

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

124

Iterative Decoding Algorithm in the Adaptive Modulation and Coding System with MIMO Schemes  

NASA Astrophysics Data System (ADS)

In this paper, we propose and analyze the adaptive modulation system with optimal Turbo Coded V-BLAST (Vertical-Bell-lab Layered Space-Time) technique that adopts extrinsic information from a MAP (Maximum A Posteriori) decoder with iterative decoding as a priori probability in two decoding procedures of V-BLAST scheme; the ordering and the slicing. Also, we consider the AMC (Adaptive Modulation and Coding) using the conventional Turbo Coded V-BLAST technique that simply combines the V-BLAST scheme with the turbo coding scheme. And we compare the proposed iterative decoding algorithm to a conventional V-BLAST decoding algorithm and a ML (Maximum Likelihood) decoding algorithm. In this analysis, the MIMO (Multiple Input Multiple Output) and the STD (Selection Transmit Diversity) schemes are assumed to be parts of the system for performance improvement. Results indicate that the proposed systems achieve better throughput performance than the conventional systems over the whole SNR (Signal to Noise Ratio) range. In terms of transmission rate performance, the suggested system is close in proximity to the conventional system using the ML decoding algorithm. In addition, the simulation result shows that the maximum throughput improvement in each MIMO scheme is respectively about 350kbps, 460kbps, and 740kbps. It is suggested that the effect of the proposed iterative decoding algorithm accordingly gets higher as the number of system antenna increases.

Ryoo, Sangjin; Lee, Kyunghwan; You, Cheolwoo; Hwang, Intae

125

Short term hydroelectric power system scheduling with wind turbine generators using the multi-pass iteration particle swarm optimization approach  

Microsoft Academic Search

This paper uses multi-pass iteration particle swarm optimization (MIPSO) to solve short term hydroelectric generation scheduling of a power system with wind turbine generators. MIPSO is a new algorithm for solving nonlinear optimal scheduling problems. A new index called iteration best (IB) is incorporated into particle swarm optimization (PSO) to improve solution quality. The concept of multi-pass dynamic programming is

Tsung-Ying Lee

2008-01-01

126

Improved successive iteration method for simulatinglaser beam propagation through multipass amplifier systems  

NASA Astrophysics Data System (ADS)

The improved successive iteration flowchart of both forward and backward codes is proposed, in which the effects of fabrication imperfections and obscurations of optical components, stochastic phase fluctuations and irradiance-dependent nonlinear index of refraction of active medium, all are important issues central to the design of high-power multipass laser systems, are considered. Typical numerical results for the four- and two-pass amplifier systems often used in practice are given to illustrate the application of our method.

Lu, Baida; Zhang, B. I. N.

127

A particular iterative learning control scheme for linear time-varying continuous systems with input delays  

Microsoft Academic Search

This paper deals with iterative learning control (ILC) design for a class of multi-input multi-output (MIMO), linear time-varying (LTV) continuous systems with input delays. A particular ILC scheme is considered, and is shown to be convergent from the two-dimensional (2D) system point of view. Furthermore, if certain selections of learning gains are met, then this scheme converges in an ordered

Deyuan Meng; Yingmin Jia; Junping Due; Shiying Yuan

2008-01-01

128

Iterative learning control of a camless valve actuation system with internal feedback  

Microsoft Academic Search

This paper presents the iterative learning control of an electro-hydraulic fully flexible engine valve actuation system. The specific camless system has a unique hydro- mechanical feedback mechanism that simplifies the external control to the choice of triggering timings for three two-state valves. All the critical parameters describing the engine valve event, i.e. lift, duration, timing, and seating velocity, can be

Adam Heinzen; Pradeep Gillella; Zongxuan Sun

2011-01-01

129

ANAEROBIC COMPOST CONSTRUCTED WETLANDS SYSTEM TECHNOLOGY - SITE ITER  

EPA Science Inventory

In Fall 1994, anaerobic compost wetlands in both upflow and downflow configurations were constructed adjacent to and received drainage from the Burleigh Tunnel, which forms part of the Clear Creek/Central City Superfund site. The systems were operated over a 3 year period. The e...

130

Materials issues in diagnostic systems for BPX and ITER  

SciTech Connect

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.

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

131

El Paso Electric photovoltaic-system analyses  

SciTech Connect

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)

Not Available

1982-05-01

132

Confined alpha particle diagnostic system using an energetic He{sup 0} beam for ITER  

SciTech Connect

The beam neutralization system for measurement of the spatial and velocity distributions of alpha particles of ITER plasmas was studied. As forward angle detection against the beam injection direction is required for effective neutralization, arrangement of the measurement system using possible ports in ITER configuration is proposed. The count rate of neutralized alpha particles produced by the double charge exchange interaction with energetic He{sup 0} beam particles injected is estimated. The ratios of signal to neutron-induced noise are evaluated. When a He{sup 0} beam produced by autodetachment from a 1-1.5 MeV He{sup -} beam of 10 mA is injected, the signal to noise ratio becomes greater than 1 at {rho}<0.4, even without beam modulation. Usage of a lock-in technique at the frequency of radio-frequency quadrapole accelerator will make measurement at the outer region possible.

Sasao, M.; Shinto, K.; Isobe, M.; Nishiura, M.; Kaneko, O.; Wada, M.; Walker, C. I.; Kitajima, S.; Okamoto, A.; Sugawara, H.; Takeuchi, S.; Tanaka, N.; Aoyama, H.; Kisaki, M. [Tohoku University, Aoba, Sendai 980-8579 (Japan); National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan); ITER Joint Work Site, Cadarache, 13108 Saint-Paul-lez-Durance cedex (France); Tohoku University, Aoba, Sendai 980-8579 (Japan)

2006-10-15

133

Total-system performance assessment for Yucca Mountain - SNL second iteration (TSPA-1993); Volume 1  

SciTech Connect

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.

Wilson, M.L.; Gauthier, J.H.; Barnard, R.W.; Barr, G.E.; Dockery, H.A.; Dunn, E.; Eaton, R.R.; Guerin, D.C.; Lu, N.; Martinez, M.J. [and others] [and others

1994-04-01

134

Penalized iterative waterfilling algorithm for multi-cell and multi-user OFDMA systems  

Microsoft Academic Search

We propose a penalized iterative waterfilling to improve the performance of a distributed resource allocation method in terms of quality of service (QoS) requirements in multi-cell and multi-user OFDMA systems. In the distributed resource allocation method, since each selfish user tries to maximize its own throughput (i.e., sum rate) without any information on other users, it is less likely to

Woo Jin Shin; Dong In Kim

2009-01-01

135

Recursive channel estimation algorithms for iterative receiver in MIMO-OFDM systems  

Microsoft Academic Search

A practical variational Bayes (VB) iterative receiver with joint signal detection and channel estimation is proposed in this paper for MIMO-OFDM systems in time-varying multipath channel. Since the VB method provides distribution-estimates of the parameters, the soft-input soft-output (SISO) QRD-M algorithm is exploited to estimate the signal distribution, and several channel estimation algorithms including the low complexity recursive channel estimation

Chun-lin Xiong; De-Gang Wang; Xiao-Ying Zhang; Ji-Bo Wei; Chao-Jing Tang

2009-01-01

136

Low Complexity Variational Bayes Iterative Receiver for MIMO-OFDM Systems  

Microsoft Academic Search

A low complexity iterative receiver is proposed in this paper for MIMO-OFDM systems in time-varying multi-path channel based on the variational Bayes (VB) method. According to the VB method, the estimation algorithms of the signal distribution and the channel distribution are derived for the receiver. With the aid of the soft-output QRD-M algorithm, whose complexity is fixed and relatively low,

Chun-lin Xiong; Hua Wang; Xiao-ying Zhang; Ji-bo Wei; Chao-jing Tang

2009-01-01

137

Common rail injection system iterative learning control based parameter calibration for accurate fuel injection quantity control  

Microsoft Academic Search

This paper presents an accurate engine fuel injection quantity control technique for high pressure common rail (HPCR) injection\\u000a systems by an iterative learning control (ILC)-based, on-line calibration method. Accurate fuel injection quantity control\\u000a is of importance in improving engine combustion efficiency and reducing engine-out emissions. Current Diesel engine fuel injection\\u000a quantity control algorithms are either based on pre-calibrated tables or

F. Yan; J. Wang

2011-01-01

138

Evaluation of Algebraic Iterative Image Reconstruction Methods for Tetrahedron Beam Computed Tomography Systems  

PubMed Central

Tetrahedron beam computed tomography (TBCT) performs volumetric imaging using a stack of fan beams generated by a multiple pixel X-ray source. While the TBCT system was designed to overcome the scatter and detector issues faced by cone beam computed tomography (CBCT), it still suffers the same large cone angle artifacts as CBCT due to the use of approximate reconstruction algorithms. It has been shown that iterative reconstruction algorithms are better able to model irregular system geometries and that algebraic iterative algorithms in particular have been able to reduce cone artifacts appearing at large cone angles. In this paper, the SART algorithm is modified for the use with the different TBCT geometries and is tested using both simulated projection data and data acquired using the TBCT benchtop system. The modified SART reconstruction algorithms were able to mitigate the effects of using data generated at large cone angles and were also able to reconstruct CT images without the introduction of artifacts due to either the longitudinal or transverse truncation in the data sets. Algebraic iterative reconstruction can be especially useful for dual-source dual-detector TBCT, wherein the cone angle is the largest in the center of the field of view.

Kim, Joshua; Guan, Huaiqun; Gersten, David; Zhang, Tiezhi

2013-01-01

139

Mechanical performance of cyanate ester based insulation systems under ITER relevant conditions  

NASA Astrophysics Data System (ADS)

Epoxy based glass fiber reinforced composites are candidate insulation systems for the superconducting magnet coils of fusion devices, e. g. of ITER. Because of their relatively low radiation hardness, the radiation-harder cyanate ester based systems have become of special interest for application in ITER and future fusion devices. This paper presents recent results obtained on pure cyanate ester and cyanate ester/epoxy blends reinforced with R-glass fibers/Kapton H foil. The systems were investigated at 77 K prior to and after irradiation at ambient temperature (340 K) to a fast neutron fluence of 1 × 1022 m-2 (E > 0.1 MeV) in the TRIGA reactor (Vienna). The mechanical material performance was characterized under static load conditions in tension and interlaminar shear. In addition, tension-tension fatigue measurements were carried out to simulate the pulsed operation of ITER and to assess the lifetime performance of these materials. The results show only slight mechanical degradations (by about 5 to 10%) after irradiation.

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

2006-06-01

140

High power millimeter wave experiment of ITER relevant electron cyclotron heating and current drive system  

SciTech Connect

High power, long pulse millimeter (mm) wave experiments of the RF test stand (RFTS) of Japan Atomic Energy Agency (JAEA) were performed. The system consists of a 1 MW/170 GHz gyrotron, a long and short distance transmission line (TL), and an equatorial launcher (EL) mock-up. The RFTS has an ITER-relevant configuration, i.e., consisted by a 1 MW-170 GHz gyrotron, a mm wave TL, and an EL mock-up. The TL is composed of a matching optics unit, evacuated circular corrugated waveguides, 6-miter bends, an in-line waveguide switch, and an isolation valve. The EL-mock-up is fabricated according to the current design of the ITER launcher. The Gaussian-like beam radiation with the steering capability of 20 deg. - 40 deg. from the EL mock-up was also successfully proved. The high power, long pulse power transmission test was conducted with the metallic load replaced by the EL mock-up, and the transmission of 1 MW/800 s and 0.5 MW/1000 s was successfully demonstrated with no arcing and no damages. The transmission efficiency of the TL was 96%. The results prove the feasibility of the ITER electron cyclotron heating and current drive system.

Takahashi, K.; Kajiwara, K.; Oda, Y.; Kasugai, A.; Kobayashi, N.; Sakamoto, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Doane, J.; Olstad, R. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Henderson, M. [ITER Organization, CS90 046, 13067 St. Paul lez Durance Cedex (France)

2011-06-15

141

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

SciTech Connect

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.

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

142

Implementation of iterative methods for large sparse nonsymmetric linear systems on a parallel vector machine  

SciTech Connect

This paper reports on the restructure of three outstanding iterative methods for large space nonsymmetric linear systems. These methods are CGS (conjugate gradient squared), CRS (conjugate residual squared), and Orthomin(k). The restructured methods are more suitable for vector and parallel processing. The authors implemented these methods on a parallel vector system. The linear systems for the numerical tests are obtained from discretizing four two- dimensional elliptic partial differential equations by finite difference and finite element methods. A vectorizable and parallelizable version of incomplete LU preconditioning is used. The authors restructured the subroutines to enhance the data locality in vector machines with storage hierarchy. Speedup was measured for multitasking by four processors.

Ma, S.; Chronopoulos, A.T. (Dept. of Computer Science, Univ. of Minnesota, Minneapolis, MN (US))

1990-01-01

143

Concept development for the ITER equatorial port visible/infrared wide angle viewing system  

SciTech Connect

The ITER equatorial port visible/infrared wide angle viewing system concept is developed from the measurement requirements. The proposed solution situates 4 viewing systems in the equatorial ports 3, 9, 12, and 17 with 4 views each (looking at the upper target, the inner divertor, and tangentially left and right). This gives sufficient coverage. The spatial resolution of the divertor system is 2 times higher than the other views. For compensation of vacuum-vessel movements, an optical hinge concept is proposed. Compactness and low neutron streaming is achieved by orienting port plug doglegs horizontally. Calibration methods, risks, and R and D topics are outlined.

Reichle, R.; Beaumont, B.; Boilson, D.; Bouhamou, R.; Direz, M.-F.; Encheva, A.; Henderson, M.; Kazarian, F.; Lamalle, Ph.; Lisgo, S.; Mitteau, R.; Patel, K. M.; Pitcher, C. S.; Pitts, R. A.; Prakash, A.; Raffray, R.; Schunke, B.; Snipes, J.; Diaz, A. Suarez; Udintsev, V. S. [ITER Organization, Route de Vinon-sur-Verdon, 13115 St Paul-lez-Durance (France); and others

2012-10-15

144

ITER helium ash accumulation  

SciTech Connect

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.

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

145

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

SciTech Connect

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.

Hosea J, Brunkhorst C, Fredd E, Goulding RH, Greenough N, Kung C, Rasmussen DA, Swain DW, Wilson JR

2005-10-04

146

System Requirement Analyses for Ubiquitous Environment Management System  

NASA Astrophysics Data System (ADS)

We are living in new stage of society. U-City introduces new paradigm that cannot be archived in traditional city to future city. Korea is one of the most active countries to construct U-City based on advances of IT technologies - especially based on high-speed network through out country [1]. Peoples are realizing ubiquitous service is key factor of success of U-City. Among the U-services, U-security service is one of the most important services. Nowadays we have to concern about traditional threat and also personal information. Since apartment complex is the most common residence type in Korea. We are developing security rules and system based on analyses of apartment complex and assert of apartment complex. Based on these analyses, we are developing apartment complex security using various technologies including home network system. We also will discuss basic home network security architecture.

Lim, Sang Boem; Gil, Kyung Jun; Choe, Ho Rim; Eo, Yang Dam

147

Laser power beaming system analyses. Final report  

SciTech Connect

The successful demonstration of the PAMELA adaptive optics hardware and the fabrication of the BTOS truss structure were identified by the program office as the two most critical elements of the NASA power beaming program, so it was these that received attention during this program. Much of the effort was expended in direct program support at MSFC, but detailed technical analyses of the AMP deterministic control scheme and the BTOS truss structure (both the JPL design and a spherical one) were prepared and are attached, and recommendations are given.

Zeiders, G.W. Jr.

1993-08-01

148

Static and Dynamic Performance of Newly Developed ITER Relevant Insulation Systems after Neutron Irradiation  

NASA Astrophysics Data System (ADS)

Fiber reinforced plastics will be used as insulation systems for the superconducting magnet coils of ITER. The fast neutron and gamma radiation environment present at the magnet location will lead to serious material degradation, particularly of the insulation. For this reason, advanced radiation-hard resin systems are of special interest. In this study various R-glass fiber / Kapton reinforced DGEBA epoxy and cyanate ester composites fabricated by the vacuum pressure impregnation method were investigated. All systems were irradiated at ambient temperature (340 K) in the TRIGA reactor (Vienna) to a fast neutron fluence of 1×1022 m-2 (E>0.1 MeV). Short-beam shear and static tensile tests were carried out at 77 K prior to and after irradiation. In addition, tension-tension fatigue measurements were used in order to assess the mechanical performance of the insulation systems under the pulsed operation conditions of ITER. For the cyanate ester based system the influence of interleaving Kapton layers on the static and dynamic material behavior was investigated as well.

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

2006-03-01

149

Traffic infraestructure inventory system by analyses images  

NASA Astrophysics Data System (ADS)

This paper describes a computer vision system designed to perform an inventory of traffic signals. The system consists of five Ethernet synchronized cameras; the acquisition strategy allows us to take one image per camera every other second. We then use those five images to generate a panoramic image each second. Signal detection and recognition is carried out offline. Detection of traffic signal is done in the panoramic image using the Hough transform and enhancement of HSV color space. Traffic signal recognition is made by a combination of Haar wavelet and violates Jones classifier. Finally, we present experimental results using a database of one hundred images.

Rico Martinez, Aldo I.; Camarillo-Paz, J. C.; Ornelas Rodríguez, F. J.; Gonzalez-Barbosa, José-Joel; Peña Cheng, Yazmín C.; Hurtado-Ramos, Juan B.

2011-09-01

150

A new fractal-interpolation algorithm for seismic data based on iterated function systems  

NASA Astrophysics Data System (ADS)

A new fractal-interpolation method called PPA (Pointed Point Algorithm) based on the Iterated Function System (IFS) is proposed to interpolate the signals with the expected interpolation error, solving the problem that the ordinary fractal interpolation cannot get the value of any arbitrary point directly, which has not been found in the existing literature. Experiments on the theoretical data and real field seismic data show that the proposed PPA method can not only get the expected point's value, but also get a great accuracy in the reconstruction of the seismic profile, leading to a significant improvement over other trace interpolation methods.

Zhai, Ming-Yue; Kuzma, Heidi; Rector, James W.

2010-11-01

151

Multifractal Modelling of SYM-H via Recurrent Iterated Function Systems  

NASA Astrophysics Data System (ADS)

This paper analyzes the large-scale fluctuations of the H-component magnetic field at Earth's equator during the period from 1981-2002. A multifractal characterization is applied to the SYM-H index data and it is found that previous suggestions that SYM-H is monofractal are accurate. It is demonstrated empirically that the underlying mechanism of SYM-H, presumably ring current energization and relaxation, can be captured by recurrent iterated function systems (RIFS). The RIFS model is used to simulate the measure representation of SYM-H.

Wanliss, J. A.; Anh, V. V.; Yu, Z.; Watson, S.

2004-12-01

152

Thermal mechanical analysis on the ACB-CP valve box of ITER cryogenic system  

NASA Astrophysics Data System (ADS)

ACB-CP is an auxiliary cold box used to distribute and control the cryogenic fluids to cool the cryopumps in ITER cryogenic system. A 3-D structure design is performed as a preliminary design. In order to validate the structure design, the thermal mechanical analysis on the piping must be followed. A 3-D finite element model of ACB-CP is built. The steady state thermal analysis and thermal mechanical coupling analysis of the internal piping are performed. The thermal stress distributions and the maximal thermal stress values are obtained. The results lay the reliable foundation for the design and improvement of ACB-CP.

Tang, Jiancheng; Xiong, Lianyou; Peng, Nan; Jiang, Yongcheng; Liu, Liqiang; Zhang, Liang

2012-06-01

153

Augmenting system reliability analyses with observation priors  

Microsoft Academic Search

Occasionally, a system may fail a test without an obvious component being at fault. Instead, experts may know that at least one of a set of components has failed, but there is uncertainty about which members in the set were the actual failures. When no further information is available, this missing data may be imputed using standard data augmentation (DA).

Earl Lawrence; Christine Anderson-cook

2009-01-01

154

ANALYSING RADIATION TRANSPORT THROUGH COMPLEX FENESTRATION SYSTEMS  

Microsoft Academic Search

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,

N. S. Campbell; J. K. Whittle

155

Systems Analyses of Advanced Brayton Cycles  

SciTech Connect

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.

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

2008-09-30

156

Augmenting system reliability analyses with observation priors  

SciTech Connect

Occasionally, a system may fail a test without an obvious component being at fault. Instead, experts may know that at least one of a set of components has failed, but there is uncertainty about which members in the set were the actual failures. When no further information is available, this missing data may be imputed using standard data augmentation (DA). This process is already used in the current implementation of the JMP complex-system reliability modeling codes. In some cases when this situation arises, there may be some supplemental information about the nature of the failure that suggests which subset of components are more likely to have failed. the behavior of the system during the failure may make certain components more likely candidates, and lead the engineering experts to have certain prior beliefs about what occurred. In this case, it is still known that at least one of a set of components failed, but the experts have some idea that certain failure scenarios are more likely than others. This white paper addresses this situation by modifying the imputation process of data augmentation through the use of an observation prior. This prior is specific to particular observations, and a given outcome which is repeated several times could potentially have different observation priors associated with each occurrence.

Lawrence, Earl [Los Alamos National Laboratory; Anderson-cook, Christine [Los Alamos National Laboratory

2009-01-01

157

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

PubMed

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. PMID:23130796

Arnoux, G; Devaux, S; Alves, D; Balboa, I; Balorin, C; Balshaw, N; Beldishevski, M; Carvalho, P; Clever, M; Cramp, S; de Pablos, J-L; de la Cal, E; Falie, D; Garcia-Sanchez, P; Felton, R; Gervaise, V; Goodyear, A; Horton, A; Jachmich, S; Huber, A; Jouve, M; Kinna, D; Kruezi, U; Manzanares, A; Martin, V; McCullen, P; Moncada, V; Obrejan, K; Patel, K; Lomas, P J; Neto, A; Rimini, F; Ruset, C; Schweer, B; Sergienko, G; Sieglin, B; Soleto, A; Stamp, M; Stephen, A; Thomas, P D; Valcárcel, D F; Williams, J; Wilson, J; Zastrow, K-D

2012-10-01

158

Development of a Twin-Screw D-2 Extruder for the ITER Pellet Injection System  

SciTech Connect

A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. The extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with single-stage gas gun into the plasma. A one-fifth ITER scale prototype extruder has been built to produce a continuous solid deuterium extrusion. Deuterium gas is precooled and liquefied before being introduced into the extruder. The precooler consists of a copper vessel containing liquid nitrogen surrounded by a deuterium gas filled copper coil. The liquefier is comprised of a copper cylinder connected to a Cryomech AL330 cryocooler, which is surrounded by a copper coil that the precooled deuterium flows through. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at approximate to 15 K) before it is forced through the extruder nozzle. A viewport located below the extruder nozzle provides a direct view of the extrusion. A camera is used to document the extrusion quality and duration. A data acquisition system records the extruder temperatures, torque, and speed, upstream, and downstream pressures. This paper will describe the prototype twin-screw extruder and initial extrusion results.

Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Carbajo, Juan J [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; Foust, Charles R [ORNL; McFee, Marshall T [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Sitterson, R G [ORNL; Sparks, Dennis O [ORNL; Qualls, A L [ORNL

2009-07-01

159

Evolution of the Design of Cold Mass Support for the ITER Magnet Feeder System  

NASA Astrophysics Data System (ADS)

This paper presents the evolution of the design of cold mass support for the ITER magnet feeder system. The glass fibers in the cylinder and the flanges of the normal G10 support are discontinuous in the preliminary design. The heat load of this support from the analysis is only 4.86 W. However, the mechanical test of the prototype showed that it can only endure 9 kN lateral force, which is significantly less than the required 20 kN. So, the configuration of the glass fibers in the cylinders and flanges of this G10 support are modified by changing it to a continuous and knitted type to reinforce the support, and then a new improved prototype is manufactured and tested. It could endure 15 kN lateral forces this time, but still not meet the required 20 kN. Finally, the SS316LN material is chosen for the cold mass supports. The analysis results show that it is safe under 20 kN lateral forces with the heat load increased to 14.8 W. Considering the practical application, the requirements of strength is of primary importance. So, this SS316LN cold mass support is acceptable for the ITER magnet feeder system. On the other hand, the design idea of using continuous and knitted glass fibers to reinforce the strength of a G10 support is a good reference for the case with a lower heat load and not too high Lorentz force.

Lu, Kun; Song, Yuntao; Niu, Erwu; Zhou, Tinzhi; Wang, Zhongwei; Chen, Yonghua; Zhu, Yinfeng

2013-02-01

160

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

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

161

ITER EDA Newsletter. V. 2, no. 3.  

National Technical Information Service (NTIS)

This ITER EDA (Engineering Design Activities) Newsletter issue includes a description of the ITER Joint Central Team's management, the ITER Management System and supporting software progress, activities of the Special Working Group 2, a brief summary of a...

1993-01-01

162

Conceptual design of the collection optics for the edge Thomson scattering system in ITER  

SciTech Connect

Neutron and gamma-ray irradiation complicates the design of the edge Thomson scattering (TS) system in ITER. The TS light is relayed through the relaying optics with labyrinth and fiber coupling optics. Electron density of 2x10{sup 19} m{sup -3} is sufficient to measure T{sub e} and n{sub e} within a 10% and 5% margin of error, respectively, with a spatial resolution of 5 mm. This system can cover from 0.85 to 1 of the normalized minor radius. The time resolution is 10 ms, which is determined by the repetition rate of the laser device. A super-Gaussian is the ideal laser profile for the laser injection optics to avoid a breakdown of the filling gas used in density calibration through Raman scattering.

Yatsuka, E.; Hatae, T.; Kusama, Y. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Suitoh, S.; Aida, Y. [Showa Optronics Co., Ltd., Yokohama, Kanagawa 226-0006 (Japan)

2010-10-15

163

LASER VIEWING SYSTEM FOR IN-VESSEL INSPECTION AND CONTROL IN LARGE FUSION MACHINES (JET AND ITER)  

Microsoft Academic Search

An amplitude modulated laser in-vessel viewing system for JET and ITER fusion machines has been developed in ENEA Frascati laboratory for control and maintenance purposes. The system has a very versatile configuration so that it can be tailored to be applied in several fields in which the lack of accessibility and hostility of the environment of sounded target is the

M. Riva; L. Bartolini; A. Bordone; A. Coletti; M. Ferri; G. Fornetti; S. Lupini; C. Neri; C. Poggi; L. Semeraro; C. Talarico

164

MHD equilibrium methods for ITER (International Thermonuclear Experimental Reactor) PF (poloidal field) coil design and systems analysis  

SciTech Connect

Two versions of the Fusion Engineering Design Center (FEDC) free-boundary equilibrium code designed to computer the poloidal field (PF) coil current distribution of elongated, magnetically limited tokamak plasmas are demonstrated and applied to the systems analysis of the impact of plasma elongation on the design point of the International Thermonuclear Experimental Reactor (ITER). These notes were presented at the ITER Specialists' Meeting on the PF Coil System and Operational Scenario, held at the Max Planck Institute for Plasma Physics in Garching, Federal Republic of Germany, May 24--27, 1988. 8 refs., 6 figs., 4 tabs.

Strickler, D.J.; Galambos, J.D.; Peng, Y.K.M.

1989-03-01

165

Overview of ITER safety  

SciTech Connect

This paper presents an overview of safety in the International Thermonuclear Experimental Reactor (ITER) project midway through the Engineering Design Activities (EDA). We describe the safety strategy and approach used by the project. Then, we present project radiological release limits with the methodology used to determine if these release limits are met. We review the major safety functions and their implementation for ITER, previous results, and plans for upcoming safety and environmental analyses. 16 refs., 2 figs., 3 tabs.

Petti, D.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Piet, S.J. [ITER San Diego Joint Work Site, La Jolla, CA (United States)

1996-12-31

166

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

NASA Astrophysics Data System (ADS)

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 between the estimation of the linear and the nonlinear model part. It is assumed that besides the input and output signals also the full state vector of the system is available for identification. A measurement and signal processing procedure to estimate these signals for lumped mechanical systems is presented. The iterative learning control procedure relies on the calculation of the input that generates a given model output, so-called offline model inversion. A new offline nonlinear model inversion method for continuous-time, nonlinear time-invariant, state space models based on Newton's method is presented and applied to the new model structure. This model inversion method is not restricted to minimum phase models. It requires only calculation of the first order derivatives of the state space model and is applicable to multivariable models. For periodic reference signals the method yields a compact implementation in the frequency domain. Moreover it is shown that a bandwidth can be specified up to which learning is allowed when using this inversion method in the iterative learning control procedure. Experimental results for a nonlinear single-input-single-output system corresponding to a quarter car on a hydraulic test rig are presented. It is shown that the new nonlinear approach outperforms the linear iterative learning control approach which is currently used in the automotive industry on durability test rigs.

Smolders, K.; Volckaert, M.; Swevers, J.

2008-11-01

167

Iterative Channel Estimation in MIMO Antenna Selection Systems for Correlated Gauss-Markov Channel  

NASA Astrophysics Data System (ADS)

We address the issue of MIMO channel estimation with the aid of a priori temporal correlation statistics of the channel as well as the spatial correlation. The temporal correlations are incorporated to the estimation scheme by assuming the Gauss-Markov channel model. Under the MMSE criteria, the Kalman filter performs an iterative optimal estimation. To take advantage of the enhanced estimation capability, we focus on the problem of channel estimation from a partial channel measurement in the MIMO antenna selection system. We discuss the optimal training sequence design, and also the optimal antenna subset selection for channel measurement based on the statistics. In a highly correlated channel, the estimation works even when the measurements from some antenna elements are omitted at each fading block.

Naruse, Yousuke; Takada, Jun-Ichi

168

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

PubMed

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(+) ion source (2 A, the beam radius of 11.3 mm, the beam energy less than 20 keV). Present strong-focusing He(+) 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. PMID:22380323

Sasao, M; Kisaki, M; Kobuchi, T; Tsumori, K; Tanaka, N; Terai, K; Okamoto, A; Kitajima, S; Kaneko, O; Shinto, K; Wada, M

2012-02-01

169

The diagnostic system of the neutral beam injectors for ITER heating and current drive  

SciTech Connect

The neutral beam injectors for ITER are designed to deliver hydrogen or deuterium atoms accelerated at 1 MV for a total power of 34 MW. Design of the neutral beam and of the ion source test facilities is presently ongoing. Among the various activities, also the definition and assessment of necessary diagnostics are being carried out. Within this framework, requirements and constraints of the diagnostic system will be discussed in the present paper with the aim of providing data relevant for protection, operation, characterization, and improvement of the performances of the test facilities. The definition of the most suitable locations for the diagnostics and of their preliminary integration into the mechanical design will be proposed. Proposals for the extraction of signals from the high voltage components will also be presented.

Serianni, Gianluigi; Pomaro, Nicola; Pasqualotto, Roberto; Spolaore, Monica; Valisa, Marco [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, C.so Stati Uniti, 4, 35127 Padova (Italy)

2008-10-15

170

Progress of the ITER equatorial vis/IR wide angle viewing system optical design  

SciTech Connect

The equatorial vis/IR wide angle viewing system is present in four ITER diagnostic equatorial ports. This instrument will cover a large field of view with high spatial and temporal resolutions, to provide real time temperature measurements of plasma facing components, spectral data in the visible range, information on runaway electrons, and pellet tracking. This diagnostic needs to be reliable, precise, and long lasting. Its design is driven by both the tokamak severe environment and the high performances required for machine protection. The preliminary design phase is ongoing. Paramount issues are being tackled, relative to wide spectral band optical design, material choice, and optomechanical difficulties due to the limited space available for this instrument in the ports, since many other diagnostics and services are also present. Recent progress of the diagnostic optical design and status of associated R and D are presented.

Davi, M.; Corre, Y.; Guilhem, D.; Jullien, F.; Reichle, R.; Salasca, S.; Travere, J. M. [Association Euratom CEA, CEA/DSM/IRFM, Cadarache, 13108 Saint-Paul-lez-Durance (France); Cal, E. de la; Manzanares, A.; Pablos, J. L. de [Association Euratom CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Migozzi, J. B. [JBM Optique, 11 Av. de la division Leclerc, 92310 Sevres (France)

2008-10-15

171

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

SciTech Connect

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.

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

172

Combining inflation-free and iterative ensemble Kalman filters for strongly nonlinear systems  

NASA Astrophysics Data System (ADS)

The finite-size ensemble Kalman filter (EnKF-N) is an ensemble Kalman filter (EnKF) which, in perfect model condition, does not require inflation because it partially accounts for the ensemble sampling errors. For the Lorenz '63 and '95 toy-models, it was so far shown to perform as well or better than the EnKF with an optimally tuned inflation. The iterative ensemble Kalman filter (IEnKF) is an EnKF which was shown to perform much better than the EnKF in strongly nonlinear conditions, such as with the Lorenz '63 and '95 models, at the cost of iteratively updating the trajectories of the ensemble members. This article aims at further exploring the two filters and at combining both into an EnKF that does not require inflation in perfect model condition, and which is as efficient as the IEnKF in very nonlinear conditions. In this study, EnKF-N is first introduced and a new implementation is developed. It decomposes EnKF-N into a cheap two-step algorithm that amounts to computing an optimal inflation factor. This offers a justification of the use of the inflation technique in the traditional EnKF and why it can often be efficient. Secondly, the IEnKF is introduced following a new implementation based on the Levenberg-Marquardt optimisation algorithm. Then, the two approaches are combined to obtain the finite-size iterative ensemble Kalman filter (IEnKF-N). Several numerical experiments are performed on IEnKF-N with the Lorenz '95 model. These experiments demonstrate its numerical efficiency as well as its performance that offer, at least, the best of both filters. We have also selected a demanding case based on the Lorenz '63 model that points to ways to improve the finite-size ensemble Kalman filters. Eventually, IEnKF-N could be seen as the first brick of an efficient ensemble Kalman smoother for strongly nonlinear systems.

Bocquet, M.; Sakov, P.

2012-06-01

173

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

SciTech Connect

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.

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

174

The ITER VIS/IR wide angle viewing system: Challenges and on-going R and D  

SciTech Connect

The ITER tokamak is the next generation fusion device which will allow studying burning plasma obtained by a Deuterium-Tritium (D-T) fusion reaction during hundreds of seconds. ITER vacuum vessel real-time protection will be mandatory during plasma operation to avoid water leaks and critical plasma facing components degradation. The protection system will be based on a wide angle viewing system (WAVS) composed with 18 visible (VIS) and 18 infrared (IR) cameras covering 80 % of the vacuum vessel which will be one of the major imaging systems of ITER. Compared to protection systems routinely used on current tokamaks and based on imaging (VIS and/or IR), new constraints must be taken into account because of their influence on the system performance: the harsh environment (high neutron flux) and the metallic plasma facing components (both first wall and divertor). In this new demanding context, we have achieved three mandatory R and D studies starting from the understanding of the source of signals by using realistic photonic simulation up to real-time processing strategy taken into account first order optical design constraints to define what type of performance could be reached for ITER vacuum vessel protection. (authors)

Travere, J. M.; Aumeunier, M. H.; Joanny, M.; Jouve, M.; Martin, V.; Moncada, V.; Salasca, S. [CEA DSM, IRFM, F-13018 Saint Paul-Lez-Durance (France); Marot, L. [Univ. of Basel, Dept. of Physics, CH-4056 Basel (Switzerland); Chabaud, D. [OPTIS, ZE de la Farlede, F-83078 Toulon Cedex 9 (France); Ferme, J. J. [SESO, Pole d'Activite d'Aix en Provence, 305 Rue Louis Armand, F-13792 Aix en Provence Cedex 3 (France); Bremond, F.; Thonnat, M. [INRIA, 2004 route des Lucioles, F-06902 Sophia Antipolis Cedex (France)

2011-07-01

175

High voltage tests of the ITER toroidal field model coil insulation system  

Microsoft Academic Search

A superconducting Toroidal Field Model Coil (TFMC) was developed by the European Home Team within the framework of the R&D program of the International Thermonuclear Experimental Reactor (ITER) and is presently tested in the TOSKA facility of the Forschungszentrum Karlsruhe. To withstand the Lorentz forces the 98 turns of the ITER TFMC are divided into 10 pancakes, embedded in five

Stefan Fink; Albert Ulbricht; Harald Fillunger; Alex Bourquard; Michel Prevot

2002-01-01

176

The ITER magnet system program-design and R&D  

Microsoft Academic Search

The International Thermonuclear Experimental Reactor (ITER) will demonstrate the scientific and technological feasibility of fusion energy. The superconducting coils for the ITER reactor will require about 1200 tonnes of Nb3Sn strand and 650 tonnes of NbTi strand in 20 toroidal field (TF) coils (675 tonnes each), a central solenoid (1350 tonnes), and 7 poloidal field coils (4300 tonnes total). A

M. Huguet; R. J. Thome; N. Mitchell; K. Okuno

1995-01-01

177

Iterative methods for complex symmetric systems with multiple right-hand sides  

Microsoft Academic Search

. The aim of this paper is to introduce and analyze block and nonblock iterative methods to solveA[x(1); : : : ; x(s)] = [b(1); : : : ; b(s)], where A is complex symmetric. The block methods are based on short termrecurrences combined with quasi-minimization of the residual. The inner iteration of the nonblock method appliesone residual polynomial to

V. Simoncini; E. Gallopoulos

1994-01-01

178

An iterative ?-optimal control scheme for a class of discrete-time nonlinear systems with unfixed initial state.  

PubMed

In this paper, a finite horizon iterative adaptive dynamic programming (ADP) algorithm is proposed to solve the optimal control problem for a class of discrete-time nonlinear systems with unfixed initial state. A new ?-optimal control algorithm based on the iterative ADP approach is proposed that makes the performance index function iteratively converge to the greatest lower bound of all performance indices within an error ? in finite time. The convergence analysis of the proposed ADP algorithm in terms of performance index function and control policy is conducted. The optimal number of control steps can also be obtained by the proposed ?-optimal control algorithm for the unfixed initial state. Neural networks are used to approximate the performance index function, and compute the optimal control policy, respectively, for facilitating the implementation of the ?-optimal control algorithm. Finally, a simulation example is given to show the effectiveness of the proposed method. PMID:22418035

Wei, Qinglai; Liu, Derong

2012-02-24

179

ITER primary cryopump test facility  

Microsoft Academic Search

A cryopump as ITER primary vacuum pump is being developed at FZK under the European Fusion Technology Programme. The ITER vacuum system comprises 16 cryopumps operating in a cyclic mode which fulfills the vacuum requirements in all ITER operation modes. Prior to the construction of a prototype cryopump, the concept is tested on a reduced scale model pump. To test

N. Petersohn; J. C. Boissin; D. Murdoch; A. Mack

1998-01-01

180

3-D Monte Carlo analyses of shielding system in tokamak fusion reactor.  

National Technical Information Service (NTIS)

Within the framework of the ITER (International Tokamak Experimental Reactor) design program, 3D neutronics calculations were carried out to assess system shielding performances in the basic machine configuration by means of the Monte Carlo Neutron Photon...

M. Gallina L. Petrizzi V. Rado

1990-01-01

181

NBI: Progress in Physics and Engineering toward Fusion Reactors 4.ITER NB System: Compact Beamline and Design against Radiation  

Microsoft Academic Search

The present ITER NB system includes two design features: short beamline design and vacuum insulated beam source (ion source and accelerator) which sustain 1 MV high voltage under radiation environment. The short beamline design is achieved by subdividing interior of the neutraliser into narrow channels to reduce gas conductance, and hence, the gas flow rate to ensure target thickness required

Alexander Krylov; Takashi Inoue

2005-01-01

182

ADSM -- An automated distribution system modeling tool for engineering analyses  

SciTech Connect

Designing and operating the distribution system efficiently and economically requires distribution engineers to perform various analytical studies frequently. The system models for these analyses are derived from the information residing in diverse utility databases. One major problem in utilizing these databases is the data mismatch due to different software specifications and hardware platforms. This means additional effort is required to transform data among these systems before engineers can perform any distribution system analyses. The Automated Distribution System Modeler (ADSM) developed jointly at the University of Washington (UW) and Puget Sound Power and Light Co. (PSPL) provides an automated approach for the distribution system modeling. This software tool builds a unified distribution system model automatically from the utility databases and provides a generic interface to various engineering analysis tools. This paper describes the Object-Oriented design concept of such a tool and discusses the merits of the Geographic Information System (GIS) environment used as a platform for ADSM.

Wei, X.G.; Venkata, S.S. [Univ. of Washington, Seattle, WA (United States). Electric Energy Group; Sumic, Z. [Univ. of Washington, Seattle, WA (United States). Electric Energy Group]|[Puget Sound Power and Light Co., Bellevue, WA (United States)

1995-02-01

183

Design of Electron Cyclotron Heating and Current Drive System of ITER  

SciTech Connect

Since the end of EDA, the design of the Electron Cyclotron Heating and Current Drive (ECH and CD) system has been modified to respond to progress in physics understanding and change of interface conditions. Nominal RF power of 20 MW is shared by four upper launchers or one equatorial launcher RF beams are steered by front steering mirrors providing wide sweeping angle for the RF beam. DC high voltage power supply may be composed of IGBT pulse step modulators because of high frequency modulation and design flexibility to three different types of 170 GHz gyrotrons provided by three parties. The RF power from the 170 GHz gyrotron is transmitted to the launcher by 63.5 mm{phi} corrugated waveguide line and remotely switched by a waveguide switch between the upper launcher and the equatorial launcher. The ECH and CD system has also a start-up sub-system for assist of initial discharge composed of three 127.5 GHz gyrotrons and a dedicated DC high voltage power supply. Three of transmission lines are shared between 170 GHz gyrotron and 127.5 GHz gyrotron so as to inject RF beam for the start-up through the equatorial launcher. R and Ds of components for high power long pulse and mirror steering mechanism have been on-going in the parties to establish a reliable ITER ECH and CD system.

Kobayashi, N. [ITER, Cadarache (France); Bigelow, T.; Rasmussen, D. [ORNL, Oak Ridge (United States); Bonicelli, T.; Ramponi, G.; Saibene, G. [EFDA, Garching (Germany); Cirant, S. [ENEA-CNR, Milan (Italy); Denisov, G. [IAP, Nizhny Novgorod (Russian Federation); Heidinger, R.; Piosczyk, B. [FZK, Karlsruhe (Germany); Henderson, M.; Hogge, J.-P.; Thumm, M.; Tran, M. Q. [CRPP, Lausanne (Switzerland); Rao, S. L. [IPR, Bhat (India); Sakamoto, K.; Takahashi, K. [JAEA, Naka (Japan); Temkin, R. J. [MIT PSFC, Cambridge (United States); Verhoeven, A. G. A. [FOM IPP, Rijnhuizen (Netherlands); Zohm, H. [MPI IPP, Garching (Germany)

2007-09-28

184

Design of Electron Cyclotron Heating and Current Drive System of ITER  

NASA Astrophysics Data System (ADS)

Since the end of EDA, the design of the Electron Cyclotron Heating and Current Drive (ECH&CD) system has been modified to respond to progress in physics understanding and change of interface conditions. Nominal RF power of 20 MW is shared by four upper launchers or one equatorial launcher RF beams are steered by front steering mirrors providing wide sweeping angle for the RF beam. DC high voltage power supply may be composed of IGBT pulse step modulators because of high frequency modulation and design flexibility to three different types of 170 GHz gyrotrons provided by three parties. The RF power from the 170 GHz gyrotron is transmitted to the launcher by 63.5 mm? corrugated waveguide line and remotely switched by a waveguide switch between the upper launcher and the equatorial launcher. The ECH&CD system has also a start-up sub-system for assist of initial discharge composed of three 127.5 GHz gyrotrons and a dedicated DC high voltage power supply. Three of transmission lines are shared between 170 GHz gyrotron and 127.5 GHz gyrotron so as to inject RF beam for the start-up through the equatorial launcher. R&Ds of components for high power long pulse and mirror steering mechanism have been on-going in the parties to establish a reliable ITER ECH&CD system.

Kobayashi, N.; Bigelow, T.; Bonicelli, T.; Cirant, S.; Denisov, G.; Heidinger, R.; Henderson, M.; Hogge, J.-P.; Piosczyk, B.; Ramponi, G.; Rao, S. L.; Rasmussen, D.; Saibene, G.; Sakamoto, K.; Takahashi, K.; Temkin, R. J.; Thumm, M.; Tran, M. Q.; Verhoeven, A. G. A.; Zohm, H.

2007-09-01

185

Iterative methods for large scale nonlinear and linear systems. Final report, 1994--1996  

SciTech Connect

The major goal of this research has been to develop improved numerical methods for the solution of large-scale systems of linear and nonlinear equations, such as occur almost ubiquitously in the computational modeling of physical phenomena. The numerical methods of central interest have been Krylov subspace methods for linear systems, which have enjoyed great success in many large-scale applications, and newton-Krylov methods for nonlinear problems, which use Krylov subspace methods to solve approximately the linear systems that characterize Newton steps. Krylov subspace methods have undergone a remarkable development over the last decade or so and are now very widely used for the iterative solution of large-scale linear systems, particularly those that arise in the discretization of partial differential equations (PDEs) that occur in computational modeling. Newton-Krylov methods have enjoyed parallel success and are currently used in many nonlinear applications of great scientific and industrial importance. In addition to their effectiveness on important problems, Newton-Krylov methods also offer a nonlinear framework within which to transfer to the nonlinear setting any advances in Krylov subspace methods or preconditioning techniques, or new algorithms that exploit advanced machine architectures. This research has resulted in a number of improved Krylov and Newton-Krylov algorithms together with applications of these to important linear and nonlinear problems.

Walker, H.F.

1997-09-01

186

Common Ground to Analyse Privacy Coordination in Awareness Systems  

Microsoft Academic Search

This paper discusses how Clarke's theory of Common Ground can be applied to analyse how individuals connected by Awareness Systems con- jointly meet and negotiate their privacy needs. The exposition illustrates how Awareness Systems are a mechanism for helping individuals to meet their pri- vacy needs rather than as a privacy threat, as a first impression might suggest.

Natalia A. Romero; Panos Markopoulos

2005-01-01

187

Large and powerful rf-driven hydrogen plasmas: negative ions for the heating systems of ITER  

NASA Astrophysics Data System (ADS)

Negative ion sources are an excellent example for the manifold of applications of low temperature plasmas which ranges from basic research to industrial applications. One of the outstanding application areas is in fusion, where a large and powerful negative hydrogen ion source is as a central component of the neutral beam injection systems for heating and current drive of the international fusion project ITER. The challenge to extract an ion current of 57 A (D) and 69 A (H) from a low temperature hydrogen plasma at low pressure (0.3 Pa) is accompanied by the challenge to accelerate the beam to 1 MeV. Large RF sources with the size of a door operating at a power of up to 800 kW must deliver a uniform and stable negative hydrogen ion current density higher than 200 A/m^2 over the total area for one hour. Simultaneously, the amount of co-extracted electrons should be kept below one in order to avoid severe damages of the extraction system. These requirements can be met only by combining the disciplines of low temperature plasma physics, plasma surface interaction, ion beam optics, beam physics, and mechanical and electrical engineering. The state of the art and prospects of the negative hydrogen ion source development will be discussed with emphasis on the physical aspects.

Fantz, Ursel

2012-10-01

188

An iterative algorithm based on M-proximal mappings for a system of generalized implicit variational inclusions in Banach spaces  

NASA Astrophysics Data System (ADS)

In this paper, we give the notion of M-proximal mapping, an extension of P-proximal mapping given in [X.P. Ding, F.Q. Xia, A new class of completely generalized quasi-variational inclusions in Banach spaces, J. Comput. Appl. Math. 147 (2002) 369-383], for a nonconvex, proper, lower semicontinuous and subdifferentiable functional on Banach space and prove its existence and Lipschitz continuity. Further, we consider a system of generalized implicit variational inclusions in Banach spaces and show its equivalence with a system of implicit Wiener-Hopf equations using the concept of M-proximal mappings. Using this equivalence, we propose a new iterative algorithm for the system of generalized implicit variational inclusions. Furthermore, we prove the existence of solution of the system of generalized implicit variational inclusions and discuss the convergence and stability analysis of the iterative algorithm.

Kazmi, K. R.; Bhat, M. I.; Ahmad, Naeem

2009-11-01

189

Transient thermal hydraulic modeling and analysis of ITER divertor plate system  

Microsoft Academic Search

A mathematical model has been developed\\/updated to simulate the steady state and transient thermal-hydraulics of the International Thermonuclear Experimental Reactor (ITER) divertor module. The model predicts the thermal response of the armour coating, divertor plate structural materials and coolant channels. The selected heat transfer correlations cover all operating conditions of ITER under both normal and off-normal situations. The model also

Salah El-Din El-Morshedy; Ahmed Hassanein

2009-01-01

190

Qualification of the US Made Conductors for ITER TF Magnet System  

SciTech Connect

The US Domestic Agency (USDA) is one of the six suppliers of the TF conductor for ITER. In order to qualify conductors according to ITER requirements we prepared several lengths of the CICC and short samples for testing in the SULTAN facility in CRPP, Switzerland. We also fully characterized the strands that were used in these SULTAN samples. Fabrication experience and test results are presented and discussed.

Martovetsky, Nicolai N [ORNL; Hatfield, Daniel R [ORNL; Miller, John R [ORNL; Bruzzone, P. [CRPP, Switzerland; Stepanov, B. [CRPP, Switzerland; Seber, B. [University of Geneva

2010-01-01

191

Qualification of the US made conductors for ITER TF magnet system  

SciTech Connect

The US Domestic Agency (USDA) is one of the six suppliers of the TF conductor for ITER. In order to qualify conductors according to ITER requirements we prepared several lengths of the CICC and short samples for testing in the SULTAN facility in CRPP, Switzerland. We also fully characterized the strands that were used in these SULTAN samples. Fabrication experience and test results are presented and discussed.

Martovetsky, N; Hatfield, D; Miller, J; Bruzzone, P; Stepanov, B; Seber, B

2009-10-08

192

Maximum Likelihood-Based Iterated Divided Difference Filter for Nonlinear Systems from Discrete Noisy Measurements  

PubMed Central

A new filter named the maximum likelihood-based iterated divided difference filter (MLIDDF) is developed to improve the low state estimation accuracy of nonlinear state estimation due to large initial estimation errors and nonlinearity of measurement equations. The MLIDDF algorithm is derivative-free and implemented only by calculating the functional evaluations. The MLIDDF algorithm involves the use of the iteration measurement update and the current measurement, and the iteration termination criterion based on maximum likelihood is introduced in the measurement update step, so the MLIDDF is guaranteed to produce a sequence estimate that moves up the maximum likelihood surface. In a simulation, its performance is compared against that of the unscented Kalman filter (UKF), divided difference filter (DDF), iterated unscented Kalman filter (IUKF) and iterated divided difference filter (IDDF) both using a traditional iteration strategy. Simulation results demonstrate that the accumulated mean-square root error for the MLIDDF algorithm in position is reduced by 63% compared to that of UKF and DDF algorithms, and by 7% compared to that of IUKF and IDDF algorithms. The new algorithm thus has better state estimation accuracy and a fast convergence rate.

Wang, Changyuan; Zhang, Jing; Mu, Jing

2012-01-01

193

Modified alternating direction-implicit iteration method for linear systems from the incompressible Navier–Stokes equations  

Microsoft Academic Search

In order to solve the large sparse systems of linear equations arising from numerical solutions of two-dimensional steady incompressible viscous flow problems in primitive variable formulation, Ran and Yuan [On modified block SSOR iteration methods for linear systems from steady incompressible viscous flow problems, Appl. Math. Comput. 217 (2010), pp. 3050–3068] presented the block symmetric successive over-relaxation (BSSOR) and the

Yu-Hong Ran; Li Yuan

2011-01-01

194

Anti-insurance: Analysing the Health Insurance System in Australia  

Microsoft Academic Search

This paper develops a model to analyse the Australian health insurance system when individuals differ in their health risk and this risk is private information. In Australia private insurance both duplicates and supplements public insurance. We show that, absent any other interventions, this results in implicit transfers of wealth from those most at risk of adverse health to those least

Joshua S. Gans; Stephen P. King

2003-01-01

195

A formalization of Static Analyses in System F  

Microsoft Academic Search

In this paper, we propose a common theoretical framework for type based static functional analyses. The aim is to study the relationships between typing and program analysis. We present a variant of Girard's System F called F ? ?: . We prove some basic properties of F ? ?: such as strong normalization, Church-Rosser property, subject reduction etc. We show

Frédéric Prost

1999-01-01

196

Comparison between Direct and Iterative Methods to Solve the Linear Systems Arising from a Time-Dependent 2D Groundwater Flow Model.  

National Technical Information Service (NTIS)

Various methods for solving nonsymmetric linear systems are compared. Both direct and ILU preconditioned iterative solvers are considered. The linear systems arise when the implicit BDF time stepping method in combination with modified Newton is applied t...

J. G. Blom J. G. Verwer R. A. Trompert

1992-01-01

197

Image contrast enhancement through regional application of partitioned iterated function systems  

NASA Astrophysics Data System (ADS)

A new technique is presented for enhancing the contrast in digital images, combining the theory of partitioned iterated function system (PIFS) and image segmentation. The image is first segmented through the region growing segmentation technique, and the PIFS enhancement algorithm is applied separately to each image segment. The defined PIFS of each section is modeled by a contractive transformation, which consists of an affine spatial transform, as well as the linear transform of the graylevels of image segment pixels. The transformation of the graylevels is determined by two parameters that adjust the brightness and contrast of the transformed image segment. After the PIFS algorithm is applied to each extracted image segment, a lowpass version of the original image is created. The contrast-enhanced image is obtained by suitably combining the original image with its lowpass version. The proposed regional PIFS approach was applied to numerous test images, ranging from medical data of various modalities to standard images. The obtained quantitative and qualitative results showed superior performance on behalf of the proposed method when compared with three other widely used contrast enhancement methods, namely, contrast stretching, unsharp masking, and contrast-limited adaptive histogram equalization.

Koutsouri, Georgia D.; Economopoulos, Theodore L.; Matsopoulos, George K.

2013-01-01

198

Preliminary Master Logic Diagram for ITER operation  

SciTech Connect

This paper describes the work performed to develop a Master Logic Diagram (MLD) for the operations phase of the International Thermonuclear Experimental Reactor (ITER). The MLD is a probabilistic risk assessment tool used to identify the broad set of potential initiating events that could lead to an offsite radioactive or toxic chemical release from the facility under study. The MLD described here is complementary to the failure modes and effects analyses (FMEAs) that have been performed for ITER`s major plant systems in the engineering evaluation of the facility design. While the FMEAs are a bottom-up or component level approach, the MLD is a top-down or facility level approach to identifying the broad spectrum of potential events. Strengths of the MLD are that it analyzes the entire plant, depicts completeness in the accident initiator process, provides an independent method for identification, and can also identify potential system interactions. MLDs have been used successfully as a hazard analysis tool. This paper describes the process used for the ITER MLD to treat the variety of radiological and toxicological source terms present in the ITER design. One subtree of the nineteen page MLD is shown to illustrate the levels of the diagram.

Cadwallader, L.C. [INEEL, Idaho Falls, ID (United States); Taylor, N.P.; Poucet, A.E. [ITER San Diego Joint Work Site, La Jolla, CA (United States)

1998-04-01

199

Transportation systems analyses. Volume 2: Technical/programmatics  

NASA Astrophysics Data System (ADS)

The principal objective of this study is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. This report documents the three principal transportation systems analyses (TSA) efforts during the period 7 November 92 - 6 May 93. The analyses are as follows: Mixed-Fleet (STS/ELV) strategies for SSF resupply; Transportation Systems Data Book - overview; and Operations Cost Model - overview/introduction.

1993-05-01

200

Low-temperature tensile strength of the ITER-TF model coil insulation system after reactor irradiation  

Microsoft Academic Search

The windings of the superconducting magnet coils for the ITER-FEAT fusion device are affected by high mechanical stresses at cryogenic temperatures and by a radiation environment, which impose certain constraints especially on the insulating materials. A glass fiber reinforced plastic (GFRP) laminate, which consists of Kapton\\/R-glass-fiber reinforcement tapes, vacuum-impregnated in a DGEBA epoxy system, was used for the European toroidal

K Bittner-Rohrhofer; K Humer; H. W Weber

2002-01-01

201

Analysing hierarchy in the organization of biological and physical systems.  

PubMed

A structured approach is discussed for analysing hierarchy in the organization of biological and physical systems. The need for a structured approach follows from the observation that many hierarchies in the literature apply conflicting hierarchy rules and include ill-defined systems. As an alternative, we suggest a framework that is based on the following analytical steps: determination of the succession stage of the universe, identification of a specific system as part of the universe, specification of external influences on a system's creation and analysis of a system's internal organization. At the end, the paper discusses practical implications of the proposed method for the analysis of system organization and hierarchy in biology, ecology and physics. PMID:18211280

Jagers op Akkerhuis, Gerard A J M

2008-02-01

202

Enhancing the Reflexivity of System Innovation Projects with System Analyses  

ERIC Educational Resources Information Center

|Networks aiming for fundamental changes bring together a variety of actors who are part and parcel of a problematic context. These system innovation projects need to be accompanied by a monitoring and evaluation approach that supports and maintains reflexivity to be able to deal with uncertainties and conflicts while challenging current practices…

van Mierlo, Barbara; Arkesteijn, Marlen; Leeuwis, Cees

2010-01-01

203

Analysing B2B electronic procurement benefits: information systems perspective  

Microsoft Academic Search

Purpose – This paper aims to present electronic procurement benefits identified in four case companies from the information technology (IT), hi-tech sector. Design\\/methodology\\/approach – Multi-case study design was applied. The benefits reported in the companies were analysed and classified according to taxonomies from the information systems discipline. Finally, a new benefits classification was proposed. The framework was developed based on

Wojciech Piotrowicz; Zahir Irani

2010-01-01

204

Information theoretic discrepancy based iterative reconstruction (IDIR) algorithm for dual energy x-ray systems  

NASA Astrophysics Data System (ADS)

In dual energy computed tomography (DECT), two sets of projection data are acquired using a couple of independent X-ray spectra. Since the attenuation characteristic of a material without a K-edge in a typical medical X-ray spectrum range is accurately described by the linear combination of two phenomena, which are the photoelectric attenuation and the Compton scatter, the DECT is theoretically capable of separating one material from another. However, the material decomposition (MD) is still a challenging problem in DECT, since two sets of sinograms from distinct X-ray spectra are not spatially aligned in practices. To avoid this problem, the MD is often achieved by a weighted summation of two reconstructed volumes that correspond to a couple of sets of projection data, which the monochromatic approximation is generally used in the reconstruction procedure. The accuracy of the MD, therefore, can be limited due to the erroneous ignorance of the energy dependency of the acquisition model. In this paper, we propose a novel algorithm, named information theoretic discrepancy based iterative reconstruction (IDIR) algorithm, for an accurate MD in dual energy X-ray systems. The generalized information theoretic discrepancy (GID) measure is newly employed as the objective value. Using particular features of the GID, a tractable objective function for the material-selective reconstruction is derived, which accounts the exact polychromatic model of transmission tomography. Since the spectral model of measured data is explicitly considered, the accurate MD is possible even for misaligned projections. In numerical experiments, the proposed method showed superior reconstruction performance over the conventional approach.

Jang, Kwang Eun; Lee, Jongha; Lee, Kangui; Sung, Younghun; Lee, SeungDeok

2012-02-01

205

ITER tokamak device  

NASA Astrophysics Data System (ADS)

The results of the Conceptual Design Activities for the International Thermonuclear Experimental Reactor (ITER) are summarized. These activities, carried out between April 1988 and December 1990, produced a consistent set of technical characteristics and preliminary plans for co-ordinated research and development support of ITER, a conceptual design, a description of design requirements and a preliminary construction schedule and cost estimate. After a description of the design basis, an overview is given of the tokamak device, its auxiliary systems, facility and maintenance. The interrelation and integration of the various subsystems that form the ITER tokamak concept are discussed. The 16 ITER equatorial port allocations, used for nuclear testing, diagnostics, fueling, maintenance, and heating and current drive, are given, as well as a layout of the reactor building. Finally, brief descriptions are given of the major ITER sub-systems, i.e., (1) magnet systems (toroidal and poloidal field coils and cryogenic systems), (2) containment structures (vacuum and cryostat vessels, machine gravity supports, attaching locks, passive loops and active coils), (3) first wall, (4) divertor plate (design and materials, performance and lifetime, a.o.), (5) blanket/shield system, (6) maintenance equipment, (7) current drive and heating, (8) fuel cycle system, and (9) diagnostics.

Doggett, J.; Salpietro, E.; Shatalov, G.

1991-07-01

206

Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems  

SciTech Connect

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.

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

2013-01-01

207

An optimum iterative method for solving any linear system with a square matrix  

Microsoft Academic Search

A method is presented to solveAx=b by computing optimum iteration parameters for Richardson's method. It requires some information on the location of the eigenvalues ofA. The algorithm yields parameters well-suited for matrices for which Chebyshev parameters are not appropriate. It therefore supplements the Manteuffel algorithm, developed for the Chebyshev case. Numerical examples are described.

Dennis C. Smolarski; Paul E. Saylor

1988-01-01

208

Preliminary Probabilistic Safety Assessment of Chinese Dual Functional Lithium Lead Test Blanket Module System for ITER  

Microsoft Academic Search

A dual functional lithium lead (DFLL) test blanket module (TBM) concept for testing in International Thermonuclear Experimental Reactor (ITER) has been proposed. The safety assessment of DFL-TBM has been carried out applying the Probabilistic Safety Assessment (PSA) approach. The accident sequences have been modeled and quantified through the event tree technique, which allows identifying all possible combinations of success or

L. Hu; Y. Wu; J. Wang; S. WangandFDSTeam

2007-01-01

209

Study of ITER equatorial port plug handling system and vacuum sealing interface  

Microsoft Academic Search

In the field of the ITER port plug engineering and integration task, CEA has contributed to define proposals concerning the port plugs vacuum sealing interface with the vessel flange and the equatorial plug handling.The 2001 baseline vacuum flange sealing consisted of TIG welding of a 316L strip plate on to U shapes. This arrangement presented some issues like welding access,

Jean-Pierre Martins; Louis Doceul; Sébastien Marol; Elise Delchié; Jean-Jacques Cordier; Bruno Levesy; Alessandro Tesini; Emanuela Ciattaglia; Richard Tivey; René Gillier; Christophe Abbes

2009-01-01

210

Overview of Bore Tools Systems for divertor remote maintenance of ITER  

Microsoft Academic Search

Because of the radiation levels preventing direct, hands-on access to the machine components, maintenance work on ITER will eventually require the use of Remote Handling techniques. In particular, the replacement of components such as divertor and blanket modules will require the use of remote cutting, welding and Non Destructive Testing of water cooling pipes.

J.-P Friconneau; J.-P Alfille; G Cerdan; C Damiani; O David; D Maisonnier; J Palmer; Y Perrot; A Tesini; M Wojtowicz

2001-01-01

211

An iterative interacting method for dynamic analysis of the maglev train–guideway\\/foundation–soil system  

Microsoft Academic Search

This paper presents an iterative interacting method for analyzing the dynamic response of a maglev train traveling on an elevated guideway supported by piers embedded in soil. The maglev train is idealized as a row of 2D rigid beams each suspended by levitation forces and controlled by onboard PID controllers. The guideway is modeled as a series of simple beams

Y. B. Yang; J. D. Yau

2011-01-01

212

Control Theoretic Approach to Iterative Methods for Large-scale Toeplitz-type Systems with Application to Magnetic Field Analysis  

NASA Astrophysics Data System (ADS)

In this paper, stationary iterative methods for large-scale Toeplitz-type systems are investigated from a control theoretic point of view. We utilize spatially invariant structure of Toeplitz matrices, to avoid the curse of dimensionality arising in analysis and design of the convergence properties. Nonlinearities in the system are theoretically handled within the small gain and stability analysis for Lur'e systems. This theory enables us to achieve the desired global convergence of the proposed numerical scheme. We also evaluate the efficacy of the proposed method through an application to magnetic field analysis.

Oda, Tomohito; Kashima, Kenji; Imura, Jun-Ichi; Miyazaki, Shuji; Morita, Hiroshi

213

YALINA analytical benchmark analyses using the deterministic ERANOS code system.  

SciTech Connect

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.

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

2009-08-31

214

Analyses of gas composition in vacuum systems by mass spectrometry.  

PubMed

Analyses of the composition of residual gases for diagnostic purposes, analyses of the atmosphere enforced by the introduction of gases for technological purposes and analyses of gases released from analyte materials in numerous analytical methods (e.g. TSD, SIMS) are frequently carried out in vacuum systems. There is only a small amount of gas available, in the vacuum system so the most important property of a mass spectrometer is high sensitivity. As a consequence, the mass resolution is usually low. Moreover, a low outgassing rate of the mass spectrometer itself and all parts connecting it to the vacuum system is required. Dynamic mass spectrometry satisfies these demands best. Quadrupole mass spectrometers are almost solely utilized in applications, although the time-of-flight mass spectrometer has come into use recently. The main disadvantage of the quadrupole mass spectrometer is a strong dependence of the sensitivity and the mass discrimination factor on the stability of the supply voltages. Together with the necessity to use multipliers for detection of the ion current, this leads to a requirement for frequent recalibration. Another serious problem, that is met in such applications is the estimation of the gas composition from the measured mass spectra. Usually, the analyte gas mixtures consist of various individual gases, or at least are measured on a background of such mixtures. This implies a requirement for the exact knowledge of the fragmentation pattern of the gases, and again the necessity for frequent calibration over a satisfactorily wide range of mass numbers. Some theoretical considerations and some experimental results obtained by the authors are presented. PMID:12489090

Repa, P; Tesar, J; Gronych, T; Peksa, L; Wild, J

2002-12-01

215

Nonstationary iterative image restoration  

Microsoft Academic Search

This paper introduces different types of nonstationary constrained iterative image restoration algorithms. The adaptivity of the algorithm is introduced by the constraint operator which incorporates properties of the response of the human visual system. The properties of the visual system are represented by noise masking and visibility functions. A new way of computing the masking function is also introduced. The

A. Katsaggelos; J. Biemond; R. M. Mersereau; R. W. Schafer

1985-01-01

216

ITER hot cell  

Microsoft Academic Search

The paper provides an overview of the International Thermonuclear Experimental Reactor (ITER) hot cell system design. The system includes the hot cell proper, required for use both during machine assembly and operations, and the radwaste facility. The hot cell is divided in different areas and equipped with a variety of process and testing equipment. The components and waste streams are

O. Asuar; V. Baulo; T. Fisher; R. Haange; T. Honda; D. Maisonnier; D. Murdoch; C. Ozzano; J. Palmer; J. Sovka; T. Suzuki; A. Tesini; H. Yoshida

2003-01-01

217

Performance Analysis of Fixed-Margin Iterative Water-Filling for ADSL2+ and VDSL Mixed System  

NASA Astrophysics Data System (ADS)

Crosstalk is a major issue in modern ADSL and VDSL systems. Static spectrum management (SSM), the traditional way to guarantee spectrum compatibility, employs spectral masks which can be overly restrictive and result in poor performance. In this paper, fixed margin iterative water-filling algorithm is investigated in downstream VDSL and ADSL2+ scenario when they are in the same binder. The algorithm can minimize the transmission power and at the same time the overall high-quality service is guaranteed for all the users of the same binder. Simulation results show that ADSL2+ can realize performance gains of up to 80% compared with SSM techniques or ADSL.

Xu, Jian; Song, Sang Seob; Seo, Jongsoo

218

PCG: A software package for the iterative solution of linear systems on scalar, vector and parallel computers  

SciTech Connect

The expanded use of parallel computers heightens the need for numerical software which meets the joint requirements of ease of use, transportability across different architectures, state-of-the-art methods, and high megaflop rates. This study concerns the PCG package which is currently being developed to solve sparse systems of linear equations by preconditioned gradient iterative methods. Here we briefly describe the basic design and some of the features of the package. Issues involved in designing the software to be transportable across different architectures are discussed. Finally some preliminary timings for a model test problem are given to verify feasibility.

Joubert, W. (Los Alamos National Lab., NM (United States)); Carey, G.F. (Texas Univ., Austin, TX (United States). Dept. of Aerospace Engineering and Engineering Mechanics)

1993-01-01

219

Iterative Multiuser Detectors for Spatial–Frequency–Time-Domain Spread Multi-Carrier DS-CDMA Systems  

Microsoft Academic Search

This paper presents three low-complexity, yet effective, multiuser detectors (MUDs) for the uplink of spatial-fre- quency-time-domain (SFT-domain) spread multicarrier (MC) di- rect-sequence code-division multiple-access (DS-CDMA) systems. Each MUD first converts a received signal into the corresponding format. It then detects the transmitted symbols iteratively by using a one-domain (1D) minimum-mean-square-error (MMSE) detector and a two-domain (2D) MMSE detector alternately. The

Hoang-Yang Lu

2011-01-01

220

ITER reactor building design study  

Microsoft Academic Search

The International Thermonuclear Experimental Reactor (ITER) is at the midpoint of a two-year conceptual design. The ITER reactor building is a reinforced concrete structure that houses the tokamak and associated equipment and systems and forms a barrier between the tokamak and the external environment. It provides radiation shielding and controls the release of radioactive materials to the environment during both

S. L. Thomson; J. D. Blevins; M. W. Delisle

1989-01-01

221

Iter Ece:. Plans and Challenges  

Microsoft Academic Search

Measuring ECE in ITER plasmas will present several difficulties in both hardware and physics that will impede efforts to determine Tc(r,t) and characteristics of the electron distribution function. Recent work on the diagnostic systems and techniques to be employed on ITER has clarified some of these issues and found some solutions. Studies show that even with the greater relativistic broadening

M. E. Austin; P. E. Phillips; W. L. Rowan; J. Beno; H.-P. Liu; A. Ouroua; R. F. Ellis; R. W. Harvey; A. E. Hubbard; G. Taylor; D. W. Johnson

2009-01-01

222

Review of the ITER Project  

Microsoft Academic Search

ITER is planned to be the first fusion experiment operating under reactor-relevant conditions, thereby demonstrating the scientific and technological feasibility of fusion energy. ITER should accomplish this objective by demonstrating extended burn of deuterium-tritium plasmas at a fusion power of > 400 MW, by demonstrating technologies essential to a reactor in an integrated system, and by performing integrated testing of

Y. Shimomura; W. Spears

2004-01-01

223

Resolution analyses for selecting an appropriate airborne electromagnetic (AEM) system  

NASA Astrophysics Data System (ADS)

The choice of an appropriate airborne electromagnetic system for a given task should be based on a comparative analysis of candidate systems, consisting of both theoretical considerations and field studies including test lines. It has become common practice to quantify the system resolution for a series of models relevant to the survey area by comparing the sum over the data of squares of noise-normalised derivatives. We compare this analysis method with a resolution analysis based on the posterior covariance matrix of an inversion formulation. Both of the above analyses depend critically on the noise models of the systems being compared. A reasonable estimate of data noise and other sources of error is therefore of primary importance. However, data processing and noise reduction procedures, as well as other system parameters important for the modelling, are commonly proprietary, and generally it is not possible to verify whether noise figures have been arrived at by reasonable means. Consequently, it is difficult - sometimes impossible - to know if a comparative analysis has a sound basis. Nevertheless, in the real world choices have to be made, a comparative system analysis is necessary and has to be approached in a pragmatic way involving a range of different aspects. In this paper, we concentrate on the resolution analysis perspective and demonstrate that the inversion analysis must be preferred over the derivative analysis because it takes parameter coupling into account, and, furthermore, that the derivative analysis generally overestimates the resolution capability. Finally we show that impulse response data are to be preferred over step response data for near-surface resolution.

Christensen, Niels B. 13Lawrie, Ken C.

2012-07-01

224

Proposal of actively heated, long stem based Cs delivery system for diagnostic neutral beam source in ITER  

NASA Astrophysics Data System (ADS)

Positioning of Cesium (Cs) oven modules in the complex interface dominated space envelope of a negative ion source such as Diagnostic Neutral Beam (DNB) source for ITER is a challenge not only for the designer of the ion source, but also that of remote handling. A more user friendly design of the Cs delivery could emerge from the consideration of a possibility of injecting the Cs from an oven located outside the vacuum envelope of the ion source, thereby ensuring an ease of Cs refilling and oven maintenance. The design of such a delivery system involves long transmission path of lengths ~4 m, from ambient to vacuum. System design involves incorporation of a low loss transmission tube enveloped by highly reflective inner surface pipe to reduce the heat losses and therefore heating of the nearby systems. A combination of all metallic valves operated at high temperatures has been incorporated in such a way that the Cs refilling or oven maintenance can be done without breaking the ion source vacuum. Removable joints in the oven heating elements are provided at specific locations to remove the Cs oven for ion source maintenance. Experimental data on Cs transmission over such a long length, required for an effective design of a co-axial transmission, is not presently available. However, an experiment has been carried out in ITER-India making measurements of Cs distribution in coaxial transmission of a length of more than 5 m. These experiments incorporate an additional feature of multiple nozzle distributor based Cs delivery into the ion source which might help in reducing the need of multiple Cs ovens in large ion sources like ITER. The Cs flux from the oven is measured by surface ionization detector (SID). The angular distribution of the Cs flux is measured by a movable SID in linear direction and has been found in good agreement with the calculations. The Cs inventory in the oven reservoir was measured by electrical resistivity measurements methods. The paper proposes to present the measurement results and also proposes a possible configuration of the Cs oven for ITER DNB ion source.

Bansal, G.; Mishra, S.; Pandya, K.; Bandyopadhyay, M.; Soni, J.; Gahlaut, A.; Parmar, K. G.; Shah, S.; Phukan, A.; Roopesh, G.; Ahmed, I.; Chakraborty, A. K.; Singh, M. J.; Schunke, B.; Hemsworth, R.; Svensson, L.; Chareyre, J.; Graceffa, J.

2013-02-01

225

Vacuum technology for ITER  

Microsoft Academic Search

The vacuum systems for ITER are characterized by the requirements for tritium compatibility, tolerance of high magnetic and radiation fields and remote maintainability. In addition, although the vacuum levels are relatively modest, high pumping speeds are needed to achieve the high gas throughputs required. The design solutions adopted, the status of the development programme and the issues still to be

D. Murdoch; A. Antipenkov; C. Caldwell-Nichols; C. Day; M. Dremel; H. Haas; V. Hauer; H. Jensen

2008-01-01

226

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

SciTech Connect

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 relatively low aspect ratios (A = 2.5-3.0), while the engineering objective of high neutron wall load (W/sub L/ /approx gt/ 1.0 MW/m/sup 2/) leads to minimum size at higher A (/approximately/3.5). For minimum-size ITERs, the optimal toroidal field coil (TFC) designs fall within a narrow range of maximum fields (10-11 T) with R varying over only a few percent despite a factor of two change in the winding pack current density J/sub wp/. The major radius of the design is found to be sensitive to changes in elongation, inboard distances (such as plasma scrape-off), inductive flux capability, plasma temperature, beta limit, and ignition margin. A preliminary characterization of the US ITER designs with plasma current I/sub p/ > 15 MA and R < 4.5 m has been obtained by combining the engineering assumptions for devices such as the Tokamak Ignition/Burn Engineering Reactor (TIBER) with the physics assumptions for devices such as the Compact Ignition Tokamak (CIT) and the Next European Torus (NET). These devices can accommodate a range of full- to reduced-bore, driven (Q < 10), steady-state plasmas for the engineering phase that produces high neutron wall load and fluence. 12 refs., 4 figs., 3 tabs.

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

1987-01-01

227

Use of PID and Iterative Learning Controls on Improving Intra-Oral Hydraulic Loading System of Dental Implants  

NASA Astrophysics Data System (ADS)

This study presents the control design and tests of an intra-oral hydraulic system for quantitatively loading of a dental implant. The computer-controlled system was developed and employed for better pressure error compensation by PID (proportional-integral-derivative) control and point-to-point iterative learning algorithm. In vitro experiments showed that implant loading is precisely controlled (error 3%) for 0.5Hz loading without air inclusion, and reasonably performed (error<10%) with air inclusion up to 20% of the total hydraulic volume. The PID controller maintains forces at the desired level while the learning controller eliminates overshoot/undershoot at the onset of each loading cycle. The system can be potentially used for in vivo animal studies for better understanding of how bone responds to implant loading. Quantitative information derived from this biomechanical model will add to improved designs of dental implants.

Huang, Yi-Cheng; Chan, Manuel; Hsin, Yi-Ping; Ko, Ching-Chang

228

Modifying the Medical Research Council grading system through Rasch analyses  

PubMed Central

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.

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

2012-01-01

229

Modifying the Medical Research Council grading system through Rasch analyses.  

PubMed

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

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

2011-12-20

230

Radioactivity Sputtered from Cooling-Pipe Materials into Coolant in the ITER Cooling System  

SciTech Connect

The radioactivity induced by D-T neutron sputtering from piping materials to the coolant is described. The sputtering yields were calculated based on the systematics for (n,p), (n,{alpha}), (n,2n), and (n,np) reactions. Four candidate piping materials of AISI Types 316L and 304 stainless steel, Incoloy 800, and V-4 Cr-4 Ti alloy were investigated to estimate their radioactivity sputtered to the coolant. The investigation shows that radioactivity of {approx}1500 to 2000 Ci sputtered into the coolant at 1000-s plasma burn time of ITER, and after 1-day cooling, a few curies of gamma activity remain in the coolant, which will accumulate in the heat exchanger.

Ye Bangjiao [University of Science and Technology of China (China); Kasugai, Yoshimi [Japan Atomic Energy Research Institute (Japan); Ikeda, Yujiro [Japan Atomic Energy Research Institute (Japan); Fan Yangmei [University of Science and Technology of China (China); Han Rongdian [University of Science and Technology of China (China)

2001-09-15

231

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

NASA Astrophysics Data System (ADS)

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.

Xu, Jingyan; Tsui, Benjamin M. W.

2012-06-01

232

A novel infinite-time optimal tracking control scheme for a class of discrete-time nonlinear systems via the greedy HDP iteration algorithm.  

PubMed

In this paper, we aim to solve the infinite-time optimal tracking control problem for a class of discrete-time nonlinear systems using the greedy heuristic dynamic programming (HDP) iteration algorithm. A new type of performance index is defined because the existing performance indexes are very difficult in solving this kind of tracking problem, if not impossible. Via system transformation, the optimal tracking problem is transformed into an optimal regulation problem, and then, the greedy HDP iteration algorithm is introduced to deal with the regulation problem with rigorous convergence analysis. Three neural networks are used to approximate the performance index, compute the optimal control policy, and model the nonlinear system for facilitating the implementation of the greedy HDP iteration algorithm. An example is given to demonstrate the validity of the proposed optimal tracking control scheme. PMID:18632381

Zhang, Huaguang; Wei, Qinglai; Luo, Yanhong

2008-08-01

233

Preconditioned iterative solver on the coarsest level of a multi-grid method for high frequency time harmonic electromagnetic field analyses  

Microsoft Academic Search

A multi-grid method is one of the most powerful linear solvers for finite element electromagnetic field analysis. However,\\u000a as the discretized model has recently been enlarged, a solution process for a linear system arising on the coarsest level\\u000a tends to be problematic in a complete multi-grid solution process. Whereas a linear system on the coarsest level is generally\\u000a solved by

T. Iwashita; K. Yosui; M. Mori; E. Kobayashi; S. Abe

2008-01-01

234

Intelligent Control of a Sensor-Actuator System via Kernelized Least-Squares Policy Iteration  

PubMed Central

In this paper a new framework, called Compressive Kernelized Reinforcement Learning (CKRL), for computing near-optimal policies in sequential decision making with uncertainty is proposed via incorporating the non-adaptive data-independent Random Projections and nonparametric Kernelized Least-squares Policy Iteration (KLSPI). Random Projections are a fast, non-adaptive dimensionality reduction framework in which high-dimensionality data is projected onto a random lower-dimension subspace via spherically random rotation and coordination sampling. KLSPI introduce kernel trick into the LSPI framework for Reinforcement Learning, often achieving faster convergence and providing automatic feature selection via various kernel sparsification approaches. In this approach, policies are computed in a low-dimensional subspace generated by projecting the high-dimensional features onto a set of random basis. We first show how Random Projections constitute an efficient sparsification technique and how our method often converges faster than regular LSPI, while at lower computational costs. Theoretical foundation underlying this approach is a fast approximation of Singular Value Decomposition (SVD). Finally, simulation results are exhibited on benchmark MDP domains, which confirm gains both in computation time and in performance in large feature spaces.

Liu, Bo; Chen, Sanfeng; Li, Shuai; Liang, Yongsheng

2012-01-01

235

Intelligent control of a sensor-actuator system via kernelized least-squares policy iteration.  

PubMed

In this paper a new framework, called Compressive Kernelized Reinforcement Learning (CKRL), for computing near-optimal policies in sequential decision making with uncertainty is proposed via incorporating the non-adaptive data-independent Random Projections and nonparametric Kernelized Least-squares Policy Iteration (KLSPI). Random Projections are a fast, non-adaptive dimensionality reduction framework in which high-dimensionality data is projected onto a random lower-dimension subspace via spherically random rotation and coordination sampling. KLSPI introduce kernel trick into the LSPI framework for Reinforcement Learning, often achieving faster convergence and providing automatic feature selection via various kernel sparsification approaches. In this approach, policies are computed in a low-dimensional subspace generated by projecting the high-dimensional features onto a set of random basis. We first show how Random Projections constitute an efficient sparsification technique and how our method often converges faster than regular LSPI, while at lower computational costs. Theoretical foundation underlying this approach is a fast approximation of Singular Value Decomposition (SVD). Finally, simulation results are exhibited on benchmark MDP domains, which confirm gains both in computation time and in performance in large feature spaces. PMID:22736969

Liu, Bo; Chen, Sanfeng; Li, Shuai; Liang, Yongsheng

2012-02-28

236

Tests on a mock-up of the feedback controlled matching options of the ITER ICRH system  

SciTech Connect

Automatic control of the matching of the ITER ICRH antenna array on a reference load is presently developed and tested for optimization on a low-powered scaled (1:5) mock-up. Resilience to fast load variations is obtained either by 4 Conjugate-T (CT) or 4 quadrature hybrid circuits, the latter being the reference option. The main results are (i) for the CT option: successful implementation of the simultaneous feedback control of 11 actuators for the matching of the 4 CT and for the control of the array toroidal phasing; (ii) for the hybrid option: the matching and the array current control via feedback control of the decouplers and double stub tuners. This system is being progressively implemented and the simultaneous control of matching and antenna current has already been successfully tested on half of the array for heating and current drive phasings.

Grine, D.; Vervier, M.; Messiaen, A.; Dumortier, P. [Lab. for Plasma Physics-Royal Military Academy, 30 avn. de la Rermaissance, Brussels (Belgium)

2009-11-26

237

Analyses of Dynamic Response of Vehicle and Track Coupling System with Random Irregularity of Track Vertical Profile  

NASA Astrophysics Data System (ADS)

A dynamic computational model for the vehicle and track coupling system is developed by means of finite element method in this paper. In numerical implementation, the vehicle and track coupling system is divided into two parts; lower structure and upper structure. The vehicle as the upper structure in the coupling system is a whole locomotive or rolling stock with two layers of spring and damping system in which vertical and rolling motion for vehicle and bogie are involved. The lower structure in the coupling system is a railway track where rails are considered as beams with finite length rested on a double layer continuous elastic foundation. The two parts are solved independently with an iterative scheme. Coupling the vehicle system and railway track is realized through interaction forces between the wheels and the rail, where the irregularity of the track vertical profile considered as stationary ergodic Gaussian random processes and simulated by trigonometry series is included. The amplitudes of vibrations, their velocities and the accelerations generated in the vehicle and rail and the interaction forces between the vehicle and the rail due to the random irregularity of the track vertical profile and different line grades and train speeds have been analyzed numerically by this model. Analyses of system responses are performed in time and frequency domains.

Lei, X.; Noda, N.-A.

2002-11-01

238

Status of the ITER magnets  

NASA Astrophysics Data System (ADS)

The overall programme objective of ITER is to demonstrate the scientific and technological feasibility of fusion power production for peaceful purposes. ITER would accomplish this objective by demonstrating controlled burn of deuterium tritium plasmas, and by demonstrating essential technologies (of a reactor) in an integrated system. The magnetic coils of ITER are all made of superconducting conductors. A comprehensive research and development programme has been carried out to demonstrate the feasibility of the magnetic system. The major elements of this programme have been the construction of the toroidal field and central solenoid model coils. The testing of these model coils has produced all the necessary information to finalize the design of the ITER magnetic system. In addition, a poloidal field conductor insert is being manufactured and will be tested in 2006 at Naka (J) to confirm the design of the poloidal field coils.

Salpietro, E.

2006-03-01

239

A Container-Iterator Parallel Programming Model  

Microsoft Academic Search

There are several parallel programming models available for numerical computations at different levels of expressibility and ease of use. For the development of new domain specific programming models, a splitting into a distributed data container and parallel data iterators is proposed. Data distribution is implemented in application specific li- braries. Data iterators are directly analysed and compiled automatically into parallel

Gerhard W. Zumbusch

2007-01-01

240

USING SYSTEM DYNAMICS TO ANALYSE A HUMAN RESOURCES MANAGEMENT PROBLEM  

Microsoft Academic Search

System Dynamics (SD) is a powerful method for studying and managing complex feedback systems, such as one finds in business and other social systems. In this paper, a basic Human Resources Management System for a consultancy firm is described. System Dynamics is used here as the research vehicle to provide a useful insight into the whole process of hiring, training,

Ermina TOPINTZI; Manos NISTAZAKIS

241

Optics of conical electrostatic analysing and focusing systems  

Microsoft Academic Search

Energy analysis and focusing of hollow beams of charged particles may be performed with the aid of conical electrode structures. Two analyser geometries and two lens designs are described and the behaviour of some typical configurations is studied numerically. Some advantages of conical lenses over round lenses of more conventional design are indicated.

S. Ya. Yavor; L. A. Baranova

1990-01-01

242

60 Ghz Antenna System Analyses for Intersatellite Links, Phase A.  

National Technical Information Service (NTIS)

A tradeoff study for 60 GHz antenna systems applicable to an advanced Tracking and Data Acquisition System is also discussed. A conceptual design of a preferred antenna system is also discussed. The tradeoff results for four types of antenna systems are p...

1984-01-01

243

Internal Iteration Externalized  

Microsoft Academic Search

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,

Thomas Kühne

1999-01-01

244

Spaceborne power systems preference analyses. Volume 2: Decision analysis  

NASA Astrophysics Data System (ADS)

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.

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

1985-01-01

245

Implementation of Iterative Detection in Real-World MIMO Wireless Systems.  

National Technical Information Service (NTIS)

Theoretically. multiple-input multiple-output (MIMO) wireless systems can achieve remarkably high spectral efficiency as compared to conventional, single-antenna systems. This report identifies a number of problems which need to be solved in order to impl...

Y. DE Jong

2003-01-01

246

A General Framework for Analysing System Properties in Platform-Based Embedded System Designs  

Microsoft Academic Search

We present a framework (Real-Time Calculus) for analysing various system properties pertaining to timing analysis, loads on various components and on-chip buffer memory requirements of heterogeneous platform-based architectures, in a single coherent way. Many previous analysis techniques from the real-time systems domain, which are based on standard event models, turn out to be special cases of our framework. We illustrate

Samarjit Chakraborty; Simon Kunzli; Lothar Thiele

2003-01-01

247

Thermal-Hydraulic System Study of the Helium Cooled Pebble Bed (HCPB) Test Blanket Module (TBM) for ITER Using System Code RELAP5  

NASA Astrophysics Data System (ADS)

The HCPB concept has been a European DEMO reference concept for nearly one decade. Detailed thermal-hydraulic study on the control behavior of the whole system is one of the important parts of this development. The thermal-hydraulic effect of the TBM-combined cooling circuit during a cyclic operation in ITER has been studied using the system code RELAP5. The RELAP5 is based on an one-dimensional, transient two-fluid model for the flow of a two-phase steam-water mixture that can contain noncondensable components like Helium. The RELAP5-models are modified to take the cyclic operation of the circulator, heat exchanger, bypass, valves etc in to account. A sequence of operational phases is investigated, starting from the cold state through the heating phase that brings the system to a stand-by condition, followed by typical power cycles applied in ITER. The results show that the implemented control mechanisms keep the inlet temperature to the TBM and the total mass flow rate at the required values through all phases.

Jin, Xuezhou; R, Meyder

2005-04-01

248

Evolutionary prototyping: techniques for structuring the iterative development of knowledge-based systems  

Microsoft Academic Search

A knowledge-based software project management system called Dr. Watson is being developed using the automated reasoning tool (ART) and Common Lisp on Symbolics workstations. Dr. Watson has evolved over 1-1\\/2 years from a simple prototype of two to three pages of ART code to a system composed of 26 files; the current system comprises a conceptual model of project management,

Kent D. Bimson; L. B. Burris

1990-01-01

249

Analyses of grounded and ungrounded photovoltaic power systems  

NASA Astrophysics Data System (ADS)

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.

Bower, Ward; Wiles, John

250

Neutron cameras for ITER  

SciTech Connect

Neutron cameras with horizontal and vertical views have been designed for ITER, based on systems used on JET and TFTR. The cameras consist of fan-shaped arrays of collimated flight tubes, with suitably chosen detectors situated outside the biological shield. The sight lines view the ITER plasma through slots in the shield blanket and penetrate the vacuum vessel, cryostat, and biological shield through stainless steel windows. This paper analyzes the expected performance of several neutron camera arrangements for ITER. In addition to the reference designs, the authors examine proposed compact cameras, in which neutron fluxes are inferred from {sup 16}N decay gammas in dedicated flowing water loops, and conventional cameras with fewer sight lines and more limited fields of view than in the reference designs. It is shown that the spatial sampling provided by the reference designs is sufficient to satisfy target measurement requirements and that some reduction in field of view may be permissible. The accuracy of measurements with {sup 16}N-based compact cameras is not yet established, and they fail to satisfy requirements for parameter range and time resolution by large margins.

Johnson, L.C.; Barnes, C.W.; Batistoni, P. [ITER San Diego Joint Work Site, La Jolla, CA (United States)] [and others

1998-12-31

251

Iterative MultiLevel Modeling-A Methodology for Computer System Design  

Microsoft Academic Search

Abstract: The paper presents a method of modelling a computer system design as it evolves, so that evaluation can be made an integral part of the design process. The paper introduces the concept of concurrent existence, within a single model, of several representations of the system being modelled, at differing levels of abstraction. Thus important design decisions are expressed directly

Fw Zurcher; B Randell

252

Iterative MMSE Detection for MIMO/BLAST DS-CDMA Systems in Frequency Selective Fading Channels - Achieving High Performance in Fully Loaded Systems  

NASA Astrophysics Data System (ADS)

A MMSE (Minimum Mean Square Error) DS-CDMA (Direct Sequence-Code Division Multiple Access) receiver coupled with a low-complexity iterative interference suppression algorithm was devised for a MIMO/BLAST (Multiple Input, Multiple Output / Bell Laboratories Layered Space Time) system in order to improve system performance, considering frequency selective fading channels. The scheme is compared against the simple MMSE receiver, for both QPSK and 16QAM modulations, under SISO (Single Input, Single Output) and MIMO systems, the latter with 2Tx by 2Rx and 4Tx by 4Rx (MIMO order 2 and 4 respectively) antennas. To assess its performance in an existing system, the uncoded UMTS HSDPA (High Speed Downlink Packet Access) standard was considered.

Silva, João Carlos; Souto, Nuno; Cercas, Francisco; Dinis, Rui

253

Simulations and economic analyses of desiccant cooling systems  

Microsoft Academic Search

The progress to date in the development and analysis of computer simulations of solar-powered desiccant cooling using an axial-flow disc-type dehumidifier wheel, solar-powered space heating, and electrically driven, standard vapor-compression air-conditioning systems for residential use is documented. Computer simulations for both solar and conventional heating and cooling systems were performed for 12-month heating and cooling seasons. Annual thermal performance and

B. C. Shelpuk; D. W. Hooker; G. J. Jorgensen; C. E. Bingham

1979-01-01

254

Two Iterative Metaheuristic Approaches to Dynamic Memory Allocation for Embedded Systems  

Microsoft Academic Search

\\u000a Electronic embedded systems designers aim at finding a trade-off between cost and power consumption. As cache memory management\\u000a has been shown to have a significant impact on power consumption, this paper addresses dynamic memory allocation for embedded\\u000a systems with a special emphasis on time performance. In this work, time is split into time intervals, into which the application\\u000a to be

María Soto; André Rossi; Marc Sevaux

2011-01-01

255

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

NASA Astrophysics Data System (ADS)

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 of index pq = p(p-1)/2+q. Then, in the first SCF iteration step, a file of semi-ordered P supermatrix elements (or P and Q supermatrix elements in the open-shell case) is generated from the file of semi-ordered integrals. This file is processed at each iteration step in an efficient vector loop to generate the electron repulsion matrix. Convergence is automatically controlled through level-shifting techniques. The most time-consuming parts are the integral sorting and the generation of the P supermatrix, which are carried out only once. Subsequent SCF iteration steps respectively require 0.9 s and 1.7 s for the process of 107 supermatrix elements by the closed-shell and the open-shell programs on a CRAY-2 processor. Present address: Cray Research, 7 rue de Tilsitt, F-75017 Paris (France).

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

1990-08-01

256

Analysis and iterative equalization of transient and adiabatic chirp effects in DML-based OFDM transmission systems.  

PubMed

This work theoretically studies the transmission performance of a DML-based OFDM system by small-signal approximation, and the model considers both the transient and adiabatic chirps. The dispersion-induced distortion is modeled as subcarrier-to-subcarrier intermixing interference (SSII), and the theoretical SSII agrees with the distortion obtained from large-signal simulation statistically and deterministically. The analysis shows that the presence of the adiabatic chirp will ease power fading or even provide gain, but will increase the SSII to deteriorate OFDM signals after dispersive transmission. Furthermore, this work also proposes a novel iterative equalization to eliminate the SSII. From the simulation, the distortion could be effectively mitigated by the proposed equalization such that the maximum transmission distance of the DML-based OFDM signal is significantly improved. For instance, the transmission distance of a 30-Gbps DML-based OFDM signal can be extended from 10 km to more than 100 km. Besides, since the dispersion-induced distortion could be effectively mitigated by the equalization, negative power penalties are observed at some distances due to chirp-induced power gain. PMID:23187395

Wei, Chia-Chien

2012-11-01

257

Assessment of Collateral Effects to Tokamak Systems During Planned Air Baking of DIII-D to Simulate ITER Tritium Removal  

NASA Astrophysics Data System (ADS)

Thermo-oxidation is a method for removing carbon-based co-deposits and is unique in its ability to remove deuterium from tokamak co-deposits, including tile gaps and shaded areas. This is a possible technique for tritium removal on ITER. In these experiments, we examine the potential collateral (deleterious) effects of a thermo-oxidation experiment planned for DIII-D. Experiments at Toronto have set the process parameters to be 10 Torr air exposure at 250^o -350^oC for two hours. Components of interest were placed in a vacuum chamber filled with O2 or air and baked at 250^o and 350^oC. Components were examined for visual or mechanical changes, and when appropriate, mass change. In special cases, optical or electromagnetic diagnostics were performed. Components tested spanned a wide variety of materials and functions, e.g., cryopump components, structural, mechanical and diagnostic components, and fast wave antennae. To date, nearly all DIII-D systems have passed these tests. Detailed results will be presented.

Fitzpatrick, B. W. N.; Davis, J. W.; Haasz, A. A.; Stangeby, P. C.; Allen, S. L.; Ellis, R.; West, W. P.

2008-11-01

258

A Laser Metrology/Viewing System for ITER In-Vessel Inspection  

SciTech Connect

This paper identifies the requirements for a remotely operated precision laser ranging system for the International Thermonuclear Experimental Reactor. The inspection system is used for metrology and viewing, and must be capable of achieving submillimeter accuracy and operation in a reactor vessel that has high gamma radiation, high vacuum, elevated temperature, and magnetic field levels. A coherent, frequency modulated laser radar system is under development to meet these requirements. The metrology/viewing sensor consists of a compact laser-optic module linked through fiberoptics to the laser source and imaging units, located outside the harsh environment. The deployment mechanism is a remotely operated telescopic mast. Gamma irradiation up to 10{sup 7} Gy was conducted on critical sensor components with no significant impact to data transmission, and analysis indicates that critical sensor components can operate in a magnetic field with certain design modifications. Plans for testing key components in a magnetic field are underway.

Spampinato, P.T.; Barry, R.E.; Chesser, J.B.; Menon, M.M. [Oak Ridge National Lab., TN (United States); Dagher, M.A. [Boeing Rocketdyne Div., Canoga Park, CA (United States); Slotwinski, A. [Coleman Research Corp., Springfield, VA (United States)

1997-12-31

259

RF system analyses for the SSC collider rings.  

National Technical Information Service (NTIS)

The Collider RF system is required to accelerate and store a 70 mA DC proton beam from 2 TeV to 20 TeV. Various approaches have been studied as possible ways to accomplish this task. These include systemsbased on five-cell normal conducting cavities, sing...

J. Rogers P. Coleman G. Schaffer J. Wallace X. Wang

1993-01-01

260

Design and numerical analyses of the human greater circulatory system  

NASA Astrophysics Data System (ADS)

The paper presents examinations of human's greater part of the circulatory system, modeled as an electric net. The similarities between human's greater circulation and the electric model have been evolved. The analysis of the greater circulation was performed in PSPICE an environment of electric circuits modeling. The designed model allows to analyze human's greater circulation in physiological and pathological cases.

Pustelny, T.; Struk, P.; Nawrat, Z.; Gawlikowski, M.

2008-02-01

261

Analysing emerging innovation systems: a functions approach to foresight  

Microsoft Academic Search

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

Floortje Alkemade; Chris Kleinschmidt; Marko Hekkert

2007-01-01

262

An Iterative Method for Nonsymmetric Systems with Multiple Right-Hand Sides  

Microsoft Academic Search

. We propose a method for the solution of linear systems AX = B where A is alarge, possibly sparse, nonsymmetric matrix of order n, and B is an arbitrary rectangular matrixof order n \\\\Theta s with s of moderate size. The method uses a single Krylov subspace per step asa generator of approximations, a projection process, and a Richardson

V. Simoncini; E. Gallopoulos

1995-01-01

263

Analysing fundamental properties of marker-based vision system designs  

Microsoft Academic Search

This paper investigates fundamental properties of Marker-based Vision (MBV) systems. We present a theoretical analysis of the performance of basic tag designs which is extended through simulation to investigate the effects of different processing algorithms. Real-world data are processed and related to the simulated results. Image processing is performed using Cantag, an open source software toolkit for building Marker-based Vision

Andrew C. Rice; Robert K. Harle; Alastair R. Beresford

2006-01-01

264

Compression of a Monte-Carlo based system matrix for iterative reconstruction of PET images  

Microsoft Academic Search

Modern human PET-scanners often have high scatter fractions due to the lack of septa. This work treats the scatter in a straight forward manner by calculating the system matrix elements directly with Monte-Carlo (MC) methods. A parametric compression method was used to scale down memory consumption. The resulting images (reconstructed with either the compressed or with the uncompressed MC-matrix) were

Niklas Rehfeld; Markus Alber; Matthias Fippel; F. Nusslin

2004-01-01

265

Iterative Behavioral Modeling of Charge-Pump-Based Electronic Ballast–Fluorescent Lamp System  

Microsoft Academic Search

A new behavioral model for analyzing the current-source charge-pump-based ballast with a self-oscillatory gate drive circuit is proposed in this paper. A detailed model derivation is presented and the model is applied to analyze a ballast system of a 16-W compact fluorescent lamp (CFL) as an illustration. The ballast of the CFL consists of a self-oscillatory driven inverter stage and

Pok Wai Tam; Henry Shu-Hung Chung

2009-01-01

266

Systems Development as Iterative Organizational Learning: Lessons from the St Christopher House Community Learning Network  

Microsoft Academic Search

This paper reports on a study of St Christopher House (SCH), a community-based organization (CBO) that undertook an ambitious project to create a community learning network (CLN) based on a 'home-cooked' free\\/open source software (FOSS) content management system (CMS). The primary purpose of the CLN project was to provide adult learners with digital skills needed to secure employment in the

Susan MacDonald; Andrew Clement

267

Scheduling and rescheduling with iterative repair  

Microsoft Academic Search

The GERRY scheduling and rescheduling system being applied to coordinate Space Shuttle ground processing is described. The system uses constraint-based iterative repair, a technique that starts with a complete but possibly flawed schedule and iteratively improves it by using constraint knowledge within repair heuristics. The tradeoff between the informedness and the computational cost of several repair heuristics is explored. It

Monte Zweben; Eugene Davis; Brian Daun; Michael J. Deale

1993-01-01

268

An Iterative Model for Micro-Electro-Mechanical-Systems (MEMS) Deformable Mirrors  

NASA Astrophysics Data System (ADS)

We present a high accuracy Micro-Electro-Mechanical-System (MEMS) deformable mirror (DM) control algorithm which was implemented in the real-time control interface of the Subaru Coronagraphic Extreme Adaptive Optics project (SCExAO) for the on-sky engineering run of July 2011. MEMS DMs are an attractive DM technology for ExAO because they offer unprecedented actuator density and actuator counts. The small size and low cost per actuator also make them attractive for Multi-Object AO (MOAO), where one DM is needed per science field. These applications both require a DM model capable of reproducing a phase map with a precision of few nm rms. The high accuracy DM control algorithm presented below is suitable for open-loop AO systems where DM calibration is essential. For SCExAO, the high accuracy wavefront sensing uses DM modulations to coherently mix light with slow/static speckles and precisely measure their complex amplitude. Therefore, wavefront sensing and correction both depend on precise DM control. The model (described in Blain et al., 2011) which relies (i) on a physical model of the actuators and the membrane and (ii) on the optimization of 8 coefficients, could be adopted as an open-loop control solution for future MOAO or ExAO ELTs instruments. During the initial test phase at the UVic AO Lab, the performance of the model reached an open-loop error equal to 7.3% of the rms of the desired phase (1.6% of the peak-to-valley(PV) of the desired phase) with Kolmogorov type wavefront (test performed over 10 phase screens with a mean PV of 1448.3 nm and a mean rms of 489.5 nm).

Blain, Célia; Guyon, Olivier; Bradley, Colin; Martinache, Frantz; Clergeon, Christophe

2011-09-01

269

Comparison of Mode Analyses at Different Resolutions Applied to Nucleic Acid Systems  

Microsoft Academic Search

More than two decades of different types of mode analyses has shown that these techniques can be useful in describing large-scale motions in protein systems. A number of mode analyses are available and include quasiharmonics, classical normal mode, block normal mode, and the elastic network model. Each of these methods has been validated for protein systems and this variety allows

Adam W. Van Wynsberghe; Qiang Cui

2005-01-01

270

Analysing Finnish Steering System from the Perspective of Social Space: The Case of the "Campus University"  

ERIC Educational Resources Information Center

|The present study analyses Finnish higher education steering system, management by results, from the perspective of higher education institutions. We ask what happens inside a higher education institution, called here the "Campus University", during the actual negotiations related to the national steering system. We analyse not only the…

Treuthardt, Leena; Valimaa, Jussi

2008-01-01

271

Neutral particle analyser with a time of flight detection system providing a background rejection capability.  

National Technical Information Service (NTIS)

A time of flight (TOF) detection system with a background noise rejection capability has been studied experimentally. A neutral particle analyser (NPA) with mass selection capability making use of several TOF detection system has been designed. The analys...

G. Betello G. Bracco S. Mantovani B. Tilia V. Zanza

1989-01-01

272

Development and irradiation test of lost alpha detection system for ITER  

SciTech Connect

We developed a lost alpha detection system to use in burning plasma experiments. The scintillators of Ag:ZnS and polycrystalline Ce:YAG were designed for a high-temperature environment, and the optical transmission line was designed to transmit from the scintillator to the port plug. The required optical components of lenses and mirrors were irradiated using the fission reactor with the initial result that there was no clear change after the irradiation with a neutron flux of 9.6x10{sup 17} nm{sup -2} s{sup -1} for 48 h. We propose a diagnostic of alpha particle loss, so-called alpha particle induced gamma ray spectroscopy. The initial laboratory test has been carried out by the use of the Ce doped Lu{sub 2}SiO{sub 5} scintillator detector and an Am-Be source to detect the 4.44 MeV high energy gamma ray due to the {sup 9}Be({alpha},n{gamma}){sup 12}C reaction.

Nishiura, M.; Nagasaka, T.; Tanaka, T.; Ido, T. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Fujioka, K.; Fujimoto, Y. [ILE, Osaka University, 2-6 Yamada oka, Suita 565-0871 (Japan); Yamamoto, S. [Kyoto University, Gokasho Uji, Kyoto 611-0011 (Japan); Kashiwa, S.; Sasao, M. [Tohoku University, Aoba 6-01-2, Sendai 980-8579 (Japan)

2010-10-15

273

Iter and Ornl  

NASA Astrophysics Data System (ADS)

ITER (means ``the way''), a tokamak burning plasma experiment, is the next step device toward making fusion energy a reality. The programmatic objective of ITER is to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes. ITER began in 1985 as collaboration between the Russian Federation (former Soviet Union), the USA, European Union, and Japan. ITER conceptual and engineering design activities led to a detailed design in 2001. The USA opted out of the project between 1999-2003, but rejoined in 2004 for site selection and construction negotiations. China and Korea joined the project in 2003. Negotiations are continuing and a decision on the site for ITER construction [France versus Japan] is pending. The ITER international undertaking is an unprecedented scale and the six ITER parties represent 40% of the world population. By 2018, ITER will produce a fusion power of 500 million Watts for time periods up to an hour with one-tenth of the power needed to sustain it. Steady state operation is also possible at lower power levels with higher fraction of circulated power. The ITER parties invested about $1 billion into the research and development (R) and related fusion experiments to establish the ITER's feasibility. ORNL has been a key player in the ITER project and contributed to its physics and engineering design and related R since its inception. Recently, the U.S. DOE selected the PPPL/ORNL partnership to lead the U.S. project office for ITER.

Uckan, N. A.; Milora, S. L.

2004-11-01

274

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

NASA Astrophysics Data System (ADS)

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.

Sauve, Anne C.

2000-10-01

275

Mission and system analyses for satellites with unified bi-propellant propulsion systems  

NASA Astrophysics Data System (ADS)

Unified or combined liquid bi-propellant systems are being used increasingly for all propulsion needs for the new generation of communication satellites such as Intelsat VI, Olympus and Eurostar. Their characteristics have a large influence on spacecraft design, and on mission design. This paper attempts to summarize the system-level impacts of these systems, and describes in particular detail the mission design impacts. Although the discussion draws heavily upon the detailed mission analyses performed for the Olympus and Eurostar spacecraft, it attempts to retain a broader perspective in order to highlight areas that will be of common interest to a whole range of spacecraft designs. A statement of the overall advantages and disadvantages of bi-propellant systems is followed by a discussion of the spacecraft stability aspects unique to such systems. This is followed by a detailed discussion of apogee manoeuver design and related mission and operational aspects. It is shown that, though the system impacts of bi-propellant systems are many and complex, these are generally well understood, and this enables the spacecraft designer confidently to exploit the benefits that such systems can yield.

Pocha, J. J.

1984-03-01

276

US ITER limiter module design  

SciTech Connect

The recent U.S. effort on the ITER (International Thermonuclear Experimental Reactor) shield has been focused on the limiter module design. This is a multi-disciplinary effort that covers design layout, fabrication, thermal hydraulics, materials evaluation, thermo- mechanical response, and predicted response during off-normal events. The results of design analyses are presented. Conclusions and recommendations are also presented concerning, the capability of the limiter modules to meet performance goals and to be fabricated within design specifications using existing technology.

Mattas, R.F.; Billone, M.; Hassanein, A. [Argonne National Lab., IL (United States)] [and others

1996-08-01

277

Iterated Belief Revision and Conditional Logic  

Microsoft Academic Search

In this paper we propose a conditional logic called IBC to represent iterated belief revision systems. We propose a set of postulates for iterated revision which are a small variant of Darwiche and Pearl's ones. The conditional logic IBC has a standard semantics in terms of selection function models and provides a natural representation of epistemic states. We establish a

Laura Giordano; Valentina Gliozzi; Nicola Olivetti

2002-01-01

278

A Conditional Logic for Iterated Belief Revision  

Microsoft Academic Search

In this paper we propose a conditional logic to rep- resent iterated belief revision. We define an iterated belie f revision system by strengthening the postulates proposed by Darwiche and Pearl (3). First, following the line of Darwiche and Pearl, w e modify AGM postulates to make belief revision a function of epistemic states rather than of belief sets. Then

Laura Giordano; Valentina Gliozzi; Nicola Olivetti

2000-01-01

279

Variational iteration method for solving Sivashinsky equation  

NASA Astrophysics Data System (ADS)

In this paper, the solution of the evolutionary fourth-order in space, Sivashinsky equation is obtained by means of variational iteration method (VIM). The results reveal that the variational iteration method (VIM) is very effective, convenient and quite accurate to systems of nonlinear partial differential equations.

Tolou, N.; Ganji, D. D.; Zolfaghari, H.

2008-02-01

280

Active beam spectroscopy for ITER  

NASA Astrophysics Data System (ADS)

Since the first feasibility studies of active beam spectroscopy on ITER in 1995 the proposed diagnostic has developed into a well advanced and mature system. Substantial progress has been achieved on the physics side including comprehensive performance studies based on an advanced predictive code, which simulates active and passive features of the expected spectral ranges. The simulation has enabled detailed specifications for an optimized instrumentation and has helped to specify suitable diagnostic neutral beam parameters. Four ITER partners share presently the task of developing a suite of ITER active beam diagnostics, which make use of the two 0.5 MeV/amu 18 MW heating neutral beams and a dedicated 0.1 MeV/amu, 3.6 MW diagnostic neutral beam. The IN ITER team is responsible for the DNB development and also for beam physics related aspects of the diagnostic. The RF will be responsible for edge CXRS system covering the outer region of the plasma (1>r/a>0.4) using an equatorial observation port, and the EU will develop the core CXRS system for the very core (0system with better than a/30 resolution. Finally, the US will develop a dedicated MSE system making use of the HNBs and two equatorial ports. With appropriate modification, these systems could also potentially provide information on alpha particle slowing-down features.. On the engineering side, comprehensive preparations were made involving the development of an observation periscope, a neutron labyrinth optical system and design studies for remote maintenance including the exchange of the first mirror assembly, a critical issue for the operation of the CXRS diagnostic in the harsh ITER environment. Additionally, an essential change of the orientation of the DNB injection angle and specification of suitable blanket aperture has been made to avoid trapped particle damage to the first wall.

von Hellermann, M. G.; Barnsley, R.; Biel, W.; Delabie, E.; Hawkes, N.; Jaspers, R.; Johnson, D.; Klinkhamer, F.; Lischtschenko, O.; Marchuk, O.; Schunke, B.; Singh, M. J.; Snijders, B.; Summers, H. P.; Thomas, D.; Tugarinov, S.; Vasu, P.

2010-11-01

281

Iterative clipping and filtering based on discrete cosine transform/inverse discrete cosine transform for intensity modulator direct detection optical orthogonal frequency division multiplexing system  

NASA Astrophysics Data System (ADS)

Iterative clipping and filtering (ICF) is a useful technique to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals. However, the classical ICF with Fast Fourier Transform/Inverse Fast Fourier Transform requires much iteration to approach a specified PAPR threshold in the complementary cumulative distribution function. To reduce the nonlinear distortion in both electrical and optical devices and in the optical fiber, we propose a novel ICF based on discrete cosine transform/inverse discrete cosine transform to reduce the PAPR in an intensity modulator and direct detection (IM/DD) optical OFDM system. Furthermore, the new technique considerably improves bit error rate (BER) and reduces the PAPR with just few iterations. The experimental results show that the receiver sensitivity at a BER of 1 for a 2.5-Gbytes/s OFDM signal and after 200-km standard single-mode fiber transmission has been improved by 1.1, 2.3, and 3.6 dBm with launch powers of 6, 8, and 12 dBm respectively.

Mangone, Fall; Tang, Jin; Chen, Ming; Xiao, Jiangnan; Fan, Li; Chen, Lin

2013-06-01

282

The ITER port limiter design  

Microsoft Academic Search

The limiters in the International Thermonuclear Experimental Reactor (ITER) have been relocated to equatorial ports in order to improve their operability and maintenance. This position reduces to a minimum the total first wall (FW) area subjected to high heat fluxes with resulting savings in component costs along with those in the associated cooling water system. Installation in the ports allows

A. Cardella; A. Lodato; H. D. Pacher; R. R. Parker; K. Ioki; G. Janeschitz; D. Lousteau; R. Raffray; M. Yamada; C. Gusic

1998-01-01

283

ITER LHCD Plans and Design  

Microsoft Academic Search

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

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

284

Active beam spectroscopy for ITER  

Microsoft Academic Search

Since the first feasibility studies of active beam spectroscopy on ITER in 1995 the proposed diagnostic has developed into a well advanced and mature system. Substantial progress has been achieved on the physics side including comprehensive performance studies based on an advanced predictive code, which simulates active and passive features of the expected spectral ranges. The simulation has enabled detailed

M. G. von Hellermann; R. Barnsley; W. Biel; EG Delabie; NC Hawkes; RJE Jaspers; D. Johnson; F. Klinkhamer; O. Lischtschenko; O. Marchuk; B. Schunke; M. J. Singh; B. Snijders; H. P. Summers; D. Thomas; S. Tugarinov; P. Vasu

2010-01-01

285

Digital halftoning and iterative neural algorithms  

NASA Astrophysics Data System (ADS)

The application of security technology ranges from production control over supervision of special areas or objects to pattern recognition. In a lot of cases the security system deals as a preprocessor and its output should help the human visual system to detect important information. The output of hardcopy devices like printers or fax-machines is often restricted to quantized levels, so that a quantization process has to be executed. We present several attempts to perform this by the use of neural structures. The ability of layer networks and their learning algorithms lead to feedback networks. Our examination analyses the relationship between the theory of the feedback networks (especially the Hopfield net and the bidirectional associative memory net) and the iterative algorithms used in digital halftoning. This analysis allows a better understanding of the methods for digital halftoning and shows how they can benefit from each other.

Tuttass, Thomas; Bryngdahl, Olof

1994-02-01

286

Digital Squarer System for Positive Mass Identification on the ARL Ion Microprobe Mass Analyser.  

National Technical Information Service (NTIS)

The original analogue squarer for mass scale linearisation in the Ion Microprobe Mass Analyser (IMMA) has been replaced by a programmable digital squarer system which permits reliable mass number identification throughout the tested range 1 to 240. The di...

K. N. Woods L. D. V. Grant E. D. Rawsthorne H. J. Strydom W. H. Gries

1984-01-01

287

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

National Technical Information Service (NTIS)

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 electricit...

E. A. Harvego J. E. O'Brien M. G. McKellar

2012-01-01

288

Experimental vertical stability studies for ITER performance and design guidance  

NASA Astrophysics Data System (ADS)

Operating experimental devices have provided key inputs to the design process for ITER axisymmetric control. In particular, experiments have quantified controllability and robustness requirements in the presence of realistic noise and disturbance environments, which are difficult or impossible to characterize with modelling and simulation alone. This kind of information is particularly critical for ITER vertical control, which poses the highest demands on poloidal field system performance, since the consequences of loss of vertical control can be severe. This work describes results of multi-machine studies performed under a joint ITPA experiment (MDC-13) on fundamental vertical control performance and controllability limits. We present experimental results from Alcator C-Mod, DIII-D, NSTX, TCV and JET, along with analysis of these data to provide vertical control performance guidance to ITER. Useful metrics to quantify this control performance include the stability margin and maximum controllable vertical displacement. Theoretical analysis of the maximum controllable vertical displacement suggests effective approaches to improving performance in terms of this metric, with implications for ITER design modifications. Typical levels of noise in the vertical position measurement and several common disturbances which can challenge the vertical control loop are assessed and analysed.

Humphreys, D. A.; Casper, T. A.; Eidietis, N.; Ferrara, M.; Gates, D. A.; Hutchinson, I. H.; Jackson, G. L.; Kolemen, E.; Leuer, J. A.; Lister, J.; Lo Destro, L. L.; Meyer, W. H.; Pearlstein, L. D.; Portone, A.; Sartori, F.; Walker, M. L.; Welander, A. S.; Wolfe, S. M.

2009-11-01

289

The real mission of ITER  

SciTech Connect

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.

Wurden, G A [Los Alamos National Laboratory

2009-01-01

290

PFB coal fired combined cycle development program. System analyses and trade-offs (Task 1. 3)  

SciTech Connect

The systems analyses and optimization studies performed in connection with a program to design and evaluate a commercial 663 MWe coal-fired combined cycle power plant using pressurized fluidized bed combustion and advanced technology in the hot gas cleanup system and gas turbines are presented. Details on the plant control system are included. (LCL)

Not Available

1981-02-01

291

Energy analyses applied to an ocean thermal energy conversion (OTEC) system and an offshore windpower system (OWPS)  

Microsoft Academic Search

Energy analyses were applied to an ocean thermal energy conversion (OTEC) system and an offshore windpower system (OWPS) designed to supply the 1990 energy demands of the New England region. The OTEC system would involve 106,400 Mw powerplants off the Carolina coast; the OWPS system involves 81 units. Both systems use hydrogen generated onsite as an energy storage medium and

I. C. G

1979-01-01

292

Summary report for ITER Task-T19: MHD pressure drop and heat transfer study for liquid metal systems  

SciTech Connect

A key feasibility issue for the ITER Vanadium/Lithium breeding blanket is the question of insulator coatings. Design calculations show that an electrically insulating layer is necessary to maintain an acceptably low MHD pressure drop. To begin experimental investigations of the MHD performance of candidate insulator materials and the technology for putting them in place, a new test section was prepared. Aluminum oxide was chosen as the first candidate insulating material because it may be used in combination with NaK in the ITER vacuum vessel and/or the divertor. Details on the methods used to produce the aluminum oxide layer as well as the microstructures of the coating and the aluminide sublayer are presented and discussed. The overall MHD pressure drop, local MHD pressure gradient, local transverse MHD pressure difference, and surface voltage distributions in both the circumferential and the axial directions are reported and discussed. The positive results obtained here for high-temperature NaK have two beneficial implications for ITER. First, since NaK may be used in the vacuum vessel and/or the divertor, these results support the design approach of using electrically insulating coatings to substantially reduce MHD pressure drop. Secondly, while Al{sub 2}O{sub 3}/SS is not the same coating/base material combination which would be used in the advanced blanket, this work nonetheless shows that it is possible to produce a viable insulating coating which is stable in contact with a high temperature alkali metal coolant.

Reed, C.B.; Hua, T.Q.; Natesan, K. [Argonne National Lab., IL (United States); Kirillov, I.R.; Vitkovski, I.V.; Anisimov, A.M. [D.V. Efremov Scientific Research Inst. of Electrophysical Apparatus, St. Petersburg (Russian Federation). MHD-Machines Lab.

1995-03-01

293

MultiStage Iterative Antenna Training for Millimeter Wave Communications  

Microsoft Academic Search

We study 60 GHz millimeter wave communication systems employing SVD based transmit precoding and receive combining, and propose a multi-stage iterative method in training the antenna coefficients. The antenna training is carried out in multiple stages one after another, while each stage features an iterative process based on the power iteration principle. Null space projection is used as an enabling

Pengfei Xia; Su-khiong Yong; Oh Jisung; Chiu Ngo

2008-01-01

294

Iterative turbo decoder analysis based on density evolution  

Microsoft Academic Search

We track the density of extrinsic information in iterative turbo decoders by actual density evolution, and also approximate it by symmetric Gaussian density functions. The approximate model is verified by experimental measurements. We view the evolution of these density functions through an iterative decoder as a nonlinear dynamical system with feedback. Iterative decoding of turbo codes and of serially concatenated

Dariush Divsalar; Samuel Dolinar; Fabrizio Pollara

2001-01-01

295

Progress in research and development of mirrors for ITER diagnostics  

Microsoft Academic Search

Metallic mirrors will be used as plasma-viewing elements in all optical and laser diagnostic systems in ITER. In the harsh environment of ITER, the performance of mirrors will decrease mainly because of the erosion of their surfaces and deposition of impurities. The deterioration of the optical properties of diagnostic mirrors will directly affect the entire performance of the respective ITER

A. Litnovsky; V. Voitsenya; T. Sugie; G. DeTemmerman; A. E. Costley; A. J. H. Donné; K. Yu. Vukolov; I. Orlovskiy; J. N. Brooks; J. P. Allain; V. Kotov; A. Semerok; P.-Y. Thro; T. Akiyama; N. Yoshida; T. Tokunaga; K. Kawahata

2009-01-01

296

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

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

297

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

SciTech Connect

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.

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

2010-04-08

298

Low-Complexity Channel Estimation Using Short-Point FFT\\/IFFT for an Iterative Receiver in an LDPC-Coded OFDM System  

Microsoft Academic Search

A frequency-domain channel expanding technique (FD-CET) is proposed for channel estimation in an iterative receiver of a low-density\\u000a parity-check coded orthogonal frequency division multiplexing system. The FD-CET can expand a subset of the frequency-domain\\u000a channel gains to all of them in a short-point FFT\\/IFFT format. This technique is applied to estimate the channel gains utilizing\\u000a the pilots and information from

Wu Guan; Haige Xiang

299

On numerical solutions of a new coupled MKdV system by using the Adomian decomposition method and He's variational iteration method  

NASA Astrophysics Data System (ADS)

In this paper, we obtain the approximate solution for the soliton solution of a new coupled modified Korteweg-de Vries (MKdV) system with initial conditions by the Adomian decomposition method (ADM) and the variational iteration method (VIM) and then numerical results from the two methods are compared, showing that the ADM leads to more accurate results. Furthermore, the VIM overcomes the difficulty arising when calculating the Adomian polynomials, which is an important advantage over the ADM. The numerical results show that only a few terms are sufficient to obtain accurate solutions.

Inc, Mustafa; Cavlak, Ebru

2008-10-01

300

Transfer journey identification and analyses from electronic fare collection data  

Microsoft Academic Search

Understanding the behaviour of public transport passengers is key to providing a system from which passengers will derive the maximum benefit. One method of analysing this behaviour is with the use of passenger boarding data, stored in a database. Such a database may be improved by enriching the already existing dataset by applying specific algorithms. This paper describes an iterative

Markus Hofmann; M. O'Mahony

2005-01-01

301

On the safety of ITER accelerators.  

PubMed

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

Li, Ge

2013-09-01

302

Japanese Contribution to the Iter Engineering Design Activities and Preparation for the Iter Construction Phase  

NASA Astrophysics Data System (ADS)

The present paper describes the Japanese contribution to the ITER Engineering Design Activities (ITER/EDA) that continued from July 1992 to July 2001. This contribution includes variety of activities not only in the engineering design of ITER, but in physics study on database analysis and expected performance prediction, and in wide range of technology R&D for validation of the ITER design. In the physics study, the database on high bootstrap current and non-inductive current drive operations demonstrated in the JT-60U made a significant contribution to finalize the design of compact ITER. In the technology R&D, the JAERI has taken the hosting role in three out of seven large R&D projects, Nb3Sn central solenoid super-conducting magnet project, full-scale vacuum vessel sector model project, and remote maintenance project for 4 ton blanket module, in the ITER international framework. In addition, the JAERI intensively conducted the R&D for the out-of-vessel systems such as plasma heating and current drive systems. Thus the technological preparation for ITER construction has been successfully completed by the efforts of Parties in the ITER/EDA period. Now the formal governmental negotiation meetings of Parties have been held since November 2001. Along with these situations, a new organization called, "Fusion Energy Forum" has been established in May 2002 in Japan to support and encourage fusion R&D activities, in particular ITER to begin with.

Matsuda, Shinzaburo

2003-06-01

303

Precursor systems analyses of automated highway systems. AHS alternative propulsion system impact, volume 6  

NASA Astrophysics Data System (ADS)

The objective of this task was to evaluate the effect of alternative propulsion vehicles (APV's) on the Automated Highway Systems (AHS). This entailed research and literature reviews, in-house knowledge and interviews with experts in applicable fields. Background information on APV's were gathered to gain a understanding of the technology issues and problems facing APV's. An alternative propulsion vehicle does not rely on a internal combustion (IC) engine as its primary power source. Three types of vehicles were evaluated: electric vehicles (EV's); hybrid vehicles; roadway powered electric vehicles (RPEV's).

Elias, Joseph A.

1995-06-01

304

Performance Metrics for Liquid Chromatography-Tandem Mass Spectrometry Systems in Proteomics Analyses*  

PubMed Central

A major unmet need in LC-MS/MS-based proteomics analyses is a set of tools for quantitative assessment of system performance and evaluation of technical variability. Here we describe 46 system performance metrics for monitoring chromatographic performance, electrospray source stability, MS1 and MS2 signals, dynamic sampling of ions for MS/MS, and peptide identification. Applied to data sets from replicate LC-MS/MS analyses, these metrics displayed consistent, reasonable responses to controlled perturbations. The metrics typically displayed variations less than 10% and thus can reveal even subtle differences in performance of system components. Analyses of data from interlaboratory studies conducted under a common standard operating procedure identified outlier data and provided clues to specific causes. Moreover, interlaboratory variation reflected by the metrics indicates which system components vary the most between laboratories. Application of these metrics enables rational, quantitative quality assessment for proteomics and other LC-MS/MS analytical applications.

Rudnick, Paul A.; Clauser, Karl R.; Kilpatrick, Lisa E.; Tchekhovskoi, Dmitrii V.; Neta, Pedatsur; Blonder, Niksa; Billheimer, Dean D.; Blackman, Ronald K.; Bunk, David M.; Cardasis, Helene L.; Ham, Amy-Joan L.; Jaffe, Jacob D.; Kinsinger, Christopher R.; Mesri, Mehdi; Neubert, Thomas A.; Schilling, Birgit; Tabb, David L.; Tegeler, Tony J.; Vega-Montoto, Lorenzo; Variyath, Asokan Mulayath; Wang, Mu; Wang, Pei; Whiteaker, Jeffrey R.; Zimmerman, Lisa J.; Carr, Steven A.; Fisher, Susan J.; Gibson, Bradford W.; Paulovich, Amanda G.; Regnier, Fred E.; Rodriguez, Henry; Spiegelman, Cliff; Tempst, Paul; Liebler, Daniel C.; Stein, Stephen E.

2010-01-01

305

SCALE: a modular code system for performing standardized computer analyses for licensing evaluation  

Microsoft Academic Search

This manual provides documentation for a new, multi faceted computational system called SCALE (Standardized Computer Analyses for Licensing Evaluation) that has been developed to provide a standard analysis tool for use by the NRC staff and licensees in evaluating nuclear fuel facility and package designs. The SCALE system consists of several automated analytical sequences (control modules) which perform criticality, shielding,

Bucholz

1982-01-01

306

Deuterium Balmer/Stark spectroscopy and impurity profiles: First results from mirror-link divertor spectroscopy system on the JET ITER-like wall  

NASA Astrophysics Data System (ADS)

For the ITER-like wall, the JET mirror link divertor spectroscopy system was redesigned to fully cover the tungsten horizontal strike plate with faster time resolution and improved near-UV performance. Since the ITER-like wall project involves a change in JET from a carbon dominated machine to a beryllium and tungsten machine with residual carbon, the aim of the system is to provide the recycling flux, equivalent to the impinging deuterium ion flux, the impurity fluxes (C, Be, O) and tungsten sputtering fluxes and hence give information on the tungsten divertor source. In order to do this self-consistently, the system provides plasma characterization through the deuterium Balmer spectra measurements of electron density and temperature during high density. L-mode results at the density limit from Stark broadening/line ratio analysis will be presented and compared to Langmuir probe profiles and 2D-tomography of low-n Balmer emission [1]. Comparison with other diagnostics will be vital for modeling attempts with the EDGE2D-EIRENE code [2] as the best possible data sets need to be provided to study detachment.

JET EFDA Contributors Meigs, A. G.; Brezinsek, S.; Clever, M.; Huber, A.; Marsen, S.; Nicholas, C.; Stamp, M.; Zastrow, K.-D.

2013-07-01

307

Iterative image restoration algorithms  

Microsoft Academic Search

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

Aggelos K. Katsaggelos

308

Iteration, Not Induction  

ERIC Educational Resources Information Center

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…

Dobbs, David E.

2009-01-01

309

ITER cryopump handling study preliminary report.  

National Technical Information Service (NTIS)

The scope of this study was to develop a remote handling concept for the primary vacuum pumping system by performing the following tasks: review the cryopump duct configuration and remote handling requirements for cryopump replacement; initiate an ITER Cr...

T. Haines

1996-01-01

310

Status of the ITER PCS Conceptual Design  

NASA Astrophysics Data System (ADS)

Since 2010, an ITER Plasma Control System (PCS) conceptual design activity has been underway involving participants from nearly all ITER partners. The PCS Conceptual Design Review is scheduled for November 2012, at which time functional requirements generated by this activity will be reviewed. The ITER PCS must integrate control of multiple plasma parameters that are controlled separately on present devices, including plasma current, shape, position, stored energy, beta, radiation, impurity fraction, plasma profiles, multiple instabilities, and interactions with plasma facing components, as well as new parameters like fusion power, all while avoiding triggering device protection systems. Plasma control will require technologies which do not yet exist for fusion experiments. Performance and reliability requirements are an order of magnitude greater than present fusion devices due to the nuclear mission and potential consequences of control failure. We will describe experimental physics and operational objectives as defined by the ITER Organization and summarize requirements for the PCS and related systems to satisfy these.

Walker, M. L.

2012-10-01

311

Statistical analyses to support forensic interpretation for a new ten-locus STR profiling system.  

PubMed

A new ten-locus STR (short tandem repeat) profiling system was recently introduced into casework by the Forensic Science Service (FSS) and statistical analyses are described here based on data collected using this new system for the three major racial groups of the UK: Caucasian. Afro-Caribbean and Asian (of Indo-Pakistani descent). Allele distributions are compared and the FSS position with regard to routine significance testing of DNA frequency databases is discussed. An investigation of match probability calculations is carried out and the consequent analyses are shown to provide support for proposed changes in how the FSS reports DNA results when very small match probabilities are involved. PMID:11296886

Foreman, L A; Evett, I W

2001-01-01

312

Comparative Study on Sequential Iteration Approaches for Reactive Transport Codes  

NASA Astrophysics Data System (ADS)

Because of the lower computational resource requirement (comparing to the Direct Substitute Approach) Sequential Iteration Approach (SIA) has been widely adopted in a lot of reactive transport codes to couple the transport and chemical reactions and/or microbial transformations. Standard sequential iteration approach (SIA-0) couples the chemical and microbiological processes (CBP) with transport processes by accounting for the CBP as source/sink terms (CBR) of the transport equation and evaluates it using the concentration values of previous iteration. This manipulate imposes the SIA-0 having an explicit behavior and therefore the SIA-0 is conditionally convergent. Numerical efficiency of SIA-0 is also constrained by chemical characteristic time and flow and transport characteristic times. Tebes and Valocchi (1998) presented an improved sequential iteration approach to couple the Monod kinetics with transport processes and obtained better numerical efficiency than SIA-0 (Tebes and Valocchi, 1998). In this improved approach the CBR is linearized and approximated by a truncated Taylor's expansion (only keep the first order term and the direct affined term) from previous iteration to current iteration. The linear expression then can be directly coupled into transport equations which can then be solved using finite element or finite difference solver. The solution processes are carried out in iterative manner in order to guarantee number accuracy. The improved approach then is called SIA-1 and has been implemented in a hydrobiogeochemical reactive transport code, BIO-CORE2Dc (Zhang and Samper 2001 and Zhang, 2001) to deal with chemical kinetics of both heterogeneous and aqueous reactions. This paper will present, after a brief introduction of mathematical and numerical aspects of the SIA-1 approach, two comparison cases corresponding to mineral dissolution/precipitation processes in bulk and transport system, respectively, to demonstrate the high numerical efficiency of SIA-1. The convergence behaviors of both SIA-0 and SIA-1 are also analyzed and the comparison of the numerical test cases also strongly supports the conclusion of the analyses. Key words: SIA, SIA-0, SIA-1

Zhang, G.; Samper, J.

2001-12-01

313

R&D on support to ITER safety assessment  

Microsoft Academic Search

After performing its first ITER safety assessment in 2002 on behalf of the French “Autorité de Sûreté Nucléaire (ASN)”, the French “Institut de Radioprotection et de Sûreté Nucléaire (IRSN)” is now analysing the new ITER Fusion facility safety file. The operator delivered this file to the ASN as part of its request for a creation decree, legally necessary before building

J. P. Van Dorsselaere; D. Perrault; M. Barrachin; A. Bentaib; J. Bez; P. Cortès; C. Seropian; N. Trégourès; J. Vendel

2009-01-01

314

Iterative approaches to dose optimization in tomotherapy  

NASA Astrophysics Data System (ADS)

This paper will present the results of an investigation into three iterative approaches to inverse treatment planning. These techniques have been examined in the hope of developing an optimization algorithm suitable for the large-scale problems that are encountered in tomotherapy. The three iterative techniques are referred to as the ratio method, iterative least-squares minimization and the maximum-likelihood estimator. Our results indicate that each of these techniques can serve as a useful tool in tomotherapy optimization. As compared with other mathematical programming techniques, the iterative approaches can reduce both memory demands and time requirements. In this paper, the results from small- and large-scale optimizations will be analysed. It will also be demonstrated that the flexibility of the iterative techniques can be greatly enhanced through the use of dose-volume histogram based penalty functions and/or through the use of weighting factors assigned to each region of the patient. Finally, results will be presented from an investigation into the stability of the iterative techniques.

Shepard, D. M.; Olivera, G. H.; Reckwerdt, P. J.; Mackie, T. R.

2000-01-01

315

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

NASA Astrophysics Data System (ADS)

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 (||?G||<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 [1]. 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 [2]. 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.

Grine, D.; Vervier, M.; Messiaen, A.; Dumortier, P.

2011-12-01

316

Analytic and Systemic Analyses of Computer-Supported Language Learning Environments.  

ERIC Educational Resources Information Center

Examined learner perceptions of a "package" of salient dimensions of an ideal computer-supported language learning environment. Analytic and systemic analyses of learner perceptions indicated that learners perceive their learning environments in unexpected ways and that the technology has an impact on these perceptions in that it allows the…

Egbert, Joy L.; Jessup, Leonard M.

1996-01-01

317

Modeling of electromagnetic topology in analysing High Power Microwave effect on shielding system  

Microsoft Academic Search

An electromagnetic topology model used to analyse the high power microwave effect on the different electrical components is presented. The model, whose foundation is linear coupling of aperture, emphasizes on the basic concept of electromagnetic topology, the abstract in the system analysis and two parameters: the polarization of electric field and the frequency of HPM. The algorithm of graph theory

Hang Song; D.-t. Hou; D.-f. Zhou; Chao Zhang

2008-01-01

318

Dynamical systems in analysing competitiveness and co-existence among technologies  

Microsoft Academic Search

The problem of competitiveness among different technologies is analysed using ordinary differential equations and dynamic systems techniques. Specifically, we have made large use of Lyapunov linearized stability criterion. We have dealt with different kinds of conditions in the market: the static, the dynamic and unbalanced. In all cases we have considered the problem of penetrability of the market at the

Giancarlo Barbiroli; Daniele Ritelli

1997-01-01

319

Progress of IRSN R&D on ITER Safety Assessment  

NASA Astrophysics Data System (ADS)

The French "Institut de Radioprotection et de Sûreté Nucléaire" (IRSN), in support to the French "Autorité de Sûreté Nucléaire", is analysing the safety of ITER fusion installation on the basis of the ITER operator's safety file. IRSN set up a multi-year R&D program in 2007 to support this safety assessment process. Priority has been given to four technical issues and the main outcomes of the work done in 2010 and 2011 are summarized in this paper: for simulation of accident scenarios in the vacuum vessel, adaptation of the ASTEC system code; for risk of explosion of gas-dust mixtures in the vacuum vessel, adaptation of the TONUS-CFD code for gas distribution, development of DUST code for dust transport, and preparation of IRSN experiments on gas inerting, dust mobilization, and hydrogen-dust mixtures explosion; for evaluation of the efficiency of the detritiation systems, thermo-chemical calculations of tritium speciation during transport in the gas phase and preparation of future experiments to evaluate the most influent factors on detritiation; for material neutron activation, adaptation of the VESTA Monte Carlo depletion code. The first results of these tasks have been used in 2011 for the analysis of the ITER safety file. In the near future, this R&D global programme may be reoriented to account for the feedback of the latter analysis or for new knowledge.

Van Dorsselaere, J. P.; Perrault, D.; Barrachin, M.; Bentaib, A.; Gensdarmes, F.; Haeck, W.; Pouvreau, S.; Salat, E.; Seropian, C.; Vendel, J.

2012-08-01

320

Replica shuffled iterative decoding  

Microsoft Academic Search

Replica shuffled versions of iterative decoders of turbo codes, low-density parity-check codes and turbo product codes are presented. The proposed schemes converge faster than standard and previously proposed \\

Juntan Zhang; Yige Wang; Marc Fossorier; Jonathan S. Yedidia

2005-01-01

321

ITER conceptual design report.  

National Technical Information Service (NTIS)

Results of the International Thermonuclear Experimental Reactor (ITER) Conceptual Design Activity (CDA) are reported. This report covers the Terms of Reference for the project: defining the technical specifications, defining future research needs, define ...

1991-01-01

322

Neutral particle beam alternative concept for ITER  

Microsoft Academic Search

An analysis of an ITER neutral particle beam system is presented. The analysis covers the neutralizer, ion dumps, pumping, and geometric aspects. The US beam concept for ITER consists of three or four clusters of beamlines delivering approximately 80 MW total of 1.6-MeV deuterium to three or four reactor ports. Each cluster has three self-contained beamlines featuring plasma neutralizers and

D. Sedgley; J. Brook; T. Luzzi; L. Deutsch

1989-01-01

323

Iterative process for G  

Microsoft Academic Search

In this paper, the issue of multi-degree reduction of Bézier curves with C1 and G2-continuity at the end points of the curve is considered. An iterative method, which is the first of this type, is derived. It is shown that this algorithm converges and can be applied iteratively to get the required accuracy. Some examples and figures are given to

Abedallah Rababah; Stephen Mann

2011-01-01

324

Fully automated four-column capillary LC-MS system for maximizing throughput in proteomic analyses  

SciTech Connect

We describe a 4-column, high-pressure capillary liquid chromatography (LC) system for robust, high-throughput LC-MS(/MS) analyses. This system performs multiple LC separations in parallel, but staggers each of them such that the data-rich region of each separation is sampled sequentially. By allowing nearly continuous data acquisition, this design maximizes the use of the mass spectrometer. Each analytical column is connected to a corresponding ESI emitter in order to avoid the use of post-column switching and associated dead volume issues. Encoding translation stages are employed to sequentially position the emitters at the MS inlet. The high reproducibility of this system is demonstrated using consecutive analyses of global tryptic digest of the microbe Shewanella oneidensis.

Livesay, Eric A.; Tang, Keqi; Taylor, Beverley K.; Buschbach, Michael A.; Hopkins, Derek F.; Lamarche, Brian L.; Zhao, Rui; Shen, Yufeng; Orton, Daniel J.; Moore, Ronald J.; Kelly, Ryan T.; Udseth, Harold R.; Smith, Richard D.

2008-01-01

325

Results from dynamic tests and analyses of a medium diameter LMFBR piping system  

SciTech Connect

This paper presents results and observations from dynamic tests and analyses performed on an 8-in. (0.20-m) diameter, thin-walled piping system. The piping system is a scaled representation of a Liquid Metal Fast Breeder Reactor (LMFBR) large diameter piping loop. Prototypic piping restraints were employed, including mechanical snubbers, rigid struts, pipe hangers and nonintegral pipe clamps. Snapback, sine-sweep and seismic tests were performed for various restraint configurations and piping conditions. The test results are compared to analytical predictions for verification of the methods and models used in the seismic design of LMFBR piping systems. Test program conclusions and general recommendations for piping seismic analyses are presented along with a discussion of test and analysis results.

Schott, G.A.; Hulbert, G.M.; Heberling, C.F. II

1986-08-01

326

Present Status of ITER Test Blanket Development  

NASA Astrophysics Data System (ADS)

As one of the engineering test programs in ITER, the test blanket program, which utilizes ITER as a test bed to develop breeding blanket systems for fusion DEMO plants, has been planned and advanced. The Test Blanket Working Group (TBWG) has been organized to review and coordinate test programs on Test Blanket Modules(TBM). Five breeding blanket concepts have been proposed and discussed in the TBWG, and Japan is participating in the development of all of these concepts. This paper describes the status of TBM design, blanket technology and materials development for ITER TBMs. The current design and R&D status of candidate TBM concepts, which include 1) a water-cooling system with a solid breeder, 2) a helium gas-cooling system with a solid breeder, 3) a lithium-lead (LiPb) breeding system, 4) a liquid lithium breeding system, and 5) a molten salt breeding system, are presented and discussed.

Tanaka, Satoru; Akiba, Masato; Enoeda, Mikio; Hasegawa, Akira; Konishi, Satoshi; Muroga, Takeo; Sagara, Akio

327

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.  

PubMed

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. PMID:24145253

Zheng, Z; Papenhausen, E; Mueller, K

2013-10-21

328

Comparative genomic and transcriptional analyses of CRISPR systems across the genus Pyrobaculum.  

PubMed

Within the domain Archaea, the CRISPR immune system appears to be nearly ubiquitous based on computational genome analyses. Initial studies in bacteria demonstrated that the CRISPR system targets invading plasmid and viral DNA. Recent experiments in the model archaeon Pyrococcus furiosus have uncovered a novel RNA-targeting variant of the CRISPR system. Because our understanding of CRISPR system evolution in other archaea is limited, we have taken a comparative genomic and transcriptomic view of the CRISPR arrays across six diverse species within the crenarchaeal genus Pyrobaculum. We present transcriptional data from each of four species in the genus (P. aerophilum, P. islandicum, P. calidifontis, P. arsenaticum), analyzing mature CRISPR-associated small RNA abundance from over 20 arrays. Within the genus, there is remarkable conservation of CRISPR array structure, as well as unique features that are have not been studied in other archaeal systems. These unique features include: a nearly invariant CRISPR promoter, conservation of direct repeat families, the 5' polarity of CRISPR-associated small RNA abundance, and a novel CRISPR-specific association with homologues of nurA and herA. These analyses provide a genus-level evolutionary perspective on archaeal CRISPR systems, broadening our understanding beyond existing non-comparative model systems. PMID:22811677

Bernick, David L; Cox, Courtney L; Dennis, Patrick P; Lowe, Todd M

2012-07-13

329

Comparative genomic and transcriptional analyses of CRISPR systems across the genus Pyrobaculum  

PubMed Central

Within the domain Archaea, the CRISPR immune system appears to be nearly ubiquitous based on computational genome analyses. Initial studies in bacteria demonstrated that the CRISPR system targets invading plasmid and viral DNA. Recent experiments in the model archaeon Pyrococcus furiosus have uncovered a novel RNA-targeting variant of the CRISPR system. Because our understanding of CRISPR system evolution in other archaea is limited, we have taken a comparative genomic and transcriptomic view of the CRISPR arrays across six diverse species within the crenarchaeal genus Pyrobaculum. We present transcriptional data from each of four species in the genus (P. aerophilum, P. islandicum, P. calidifontis, P. arsenaticum), analyzing mature CRISPR-associated small RNA abundance from over 20 arrays. Within the genus, there is remarkable conservation of CRISPR array structure, as well as unique features that are have not been studied in other archaeal systems. These unique features include: a nearly invariant CRISPR promoter, conservation of direct repeat families, the 5? polarity of CRISPR-associated small RNA abundance, and a novel CRISPR-specific association with homologues of nurA and herA. These analyses provide a genus-level evolutionary perspective on archaeal CRISPR systems, broadening our understanding beyond existing non-comparative model systems.

Bernick, David L.; Cox, Courtney L.; Dennis, Patrick P.; Lowe, Todd M.

2012-01-01

330

ITER in-vessel components transfer using remotely controlled casks  

Microsoft Academic Search

The paper provides an overview of the ITER transfer cask system design. The system is required during the assembly and maintenance periods of ITER. The system is designed with safety as the primary goal, to ensure minimum exposure risk to personnel and to allow the reliable transfer of components between the machine and the hot cell.

A Tesini; T Honda; J Palmer; D Maisonnier; K Shibanuma

2001-01-01

331

U.S. Contributions to ITER  

SciTech Connect

The United States participates in the ITER project and program to enable the study of the science and technology of burning plasmas, a key programmatic element missing from the world fusion program. The 2003 U.S. decision to enter the ITER negotiations followed an extensive series of community and governmental reviews of the benefits, readiness, and approaches to the study of burning plasmas. This paper describes both the technical and the organizational preparations and plans for U.S. participation in the ITER construction activity: in-kind contributions, staff contributions, and cash contributions as well as supporting physics and technology research. Near-term technical activities focus on the completion of R&D and design and mitigation of risks in the areas of the central solenoid magnet, shield/blanket, diagnostics, ion cyclotron system, electron cyclotron system, pellet fueling system, vacuum system, tritium processing system, and conventional systems. Outside the project, the U .S. is engaged in preparations for the test blanket module program. Organizational activities focus on preparations of the project management arrangements to maximize the overall success of the ITER Project; elements include refinement of U.S. directions on the international arrangements, the establishment of the U.S. Domestic Agency, progress along the path of the U.S. Department of Energy's Project Management Order, and overall preparations for commencement of the fabrication of major items of equipment and for provision of staff and cash as specified in the upcoming ITER agreement.

Ned R. Sauthoff

2005-05-13

332

Characterization of a fully automated nanoelectrospray system with mass spectrometric detection for proteomic analyses.  

PubMed

Although nanoelectrospray offers low sample consumption and improved detection limits for proteomic studies, it is currently a low throughput technique because of its tedious single-sprayer alignment procedures. Here, a fully automated nanoelectrospray system for proteomic analyses with mass spectrometric detection is described and characterized. This infusion system aspirates samples from a 96-well plate using disposable pipette tips and then delivers samples to an ESI Chip. This chip is a fully integrated monolithic device consisting of a 10 x 10 array of nozzles. The automated nanoelectrospray system is easily controlled with software that allows the user simply to select the number of samples to analyze, the volume of sample to aspirate, and the spray voltage and head pressure to apply. The system offers all the advantages of conventional nanoelectrospray plus automated, high throughput analyses with no carryover. The high degree of reproducibility and lack of carryover of the system are demonstrated here using a Micromass LCT time-of-flight mass spectrometer with the infusion of six tryptic digests through all 100 nozzles of a chip. The effects of ammonium acetate and sodium dodecyl sulfate are discussed, as well as the system's ability to spray a variety of different solvents. The spray stability of whole cytochrome c in 99.9% water with 0.1% acetic acid over a 15-min period was determined to be 5.06%. Using a Thermo Finnigan LCQ Deca ion trap and SEQUEST search software, 2 fmol/microL myoglobin and 1 fmol/microL cytochrome c digests were unambiguously identified via infusion analyses. Finally, protein spots excised from two-dimensional gels of yeast and E. coli crude cell extracts were identified with the fully automated nanoelectrospray system coupled to an LCQ. PMID:19498969

Van Pelt, Colleen K; Zhang, Sheng; Henion, Jack D

2002-06-01

333

ULOF and UTOP Analyses of a Large Metal Fuel FBR Core Using a Detailed Calculation System  

Microsoft Academic Search

ULOF and UTOP analyses of a large metal fuel FBR core (1,500 MWe, averaged discharge burnup: 150 GWd\\/t) are conducted. The effect of core radial expansion is considered as the major negative feedback during the transient. A detailed analysis system is used, in which a transient core thermal-hydraulic code is coupled with three dimensional core radial deformation and reactivity feedback

Takeshi YOKOO; Hirokazu OHTA

2001-01-01

334

EU fuel cycle development priorities for ITER  

Microsoft Academic Search

The paper describes the key elements of the EU fuel cycle development for ITER. The programme is now closely focused on the systems allocated to the EU for in-kind supply. These include the isotope separation and water detritiation systems (ISS and WDS) and the cryopumps for torus exhaust, neutral beam injectors (NBI) and cryostat pumping. For all of these systems,

D. Murdoch; I. Cristescu; C. Day; M. Glugla; R. Laesser; A. Mack

2007-01-01

335

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

NASA Astrophysics Data System (ADS)

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.

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

336

SCALE: A modular code system for performing standardized computer analyses for licensing evaluation  

SciTech Connect

This Manual represents Revision 5 of the user documentation for the modular code system referred to as SCALE. The history of the SCALE code system dates back to 1969 when the current Computational Physics and Engineering Division at Oak Ridge National Laboratory (ORNL) began providing the transportation package certification staff at the U.S. Atomic Energy Commission with computational support in the use of the new KENO code for performing criticality safety assessments with the statistical Monte Carlo method. From 1969 to 1976 the certification staff relied on the ORNL staff to assist them in the correct use of codes and data for criticality, shielding, and heat transfer analyses of transportation packages. However, the certification staff learned that, with only occasional use of the codes, it was difficult to become proficient in performing the calculations often needed for an independent safety review. Thus, shortly after the move of the certification staff to the U.S. Nuclear Regulatory Commission (NRC), the NRC staff proposed the development of an easy-to-use analysis system that provided the technical capabilities of the individual modules with which they were familiar. With this proposal, the concept of the Standardized Computer Analyses for Licensing Evaluation (SCALE) code system was born. This manual covers an array of modules written for the SCALE package, consisting of drivers, system libraries, cross section and materials properties libraries, input/output routines, storage modules, and help files.

NONE

1997-03-01

337

Performance Analyses of ECCS and Containment Systems for the 4500 MW ESBWR  

SciTech Connect

GE latest evolution of the Boiling Water Reactor, the ESBWR, is an advanced, 4500 MWth nuclear power plant design, submitted to the NRC for design certification in 2005. This paper presents the key results of performance analyses of ESBWR ECCS and containment systems. The ESBWR is designed to take full advantage of passive features to improve the plant performance and economics. The key features are the use of natural circulation during normal operation and passive safety systems for decay heat removal and inventory control. The use of natural circulation results in relatively taller reactor vessel and more in-vessel coolant inventory. Consequently, the water level always covers the core following an accident, assuring no fuel heatup. The use of passive systems results in simpler safety systems. The peak containment pressure and margin to the design value basically depend on the containment volumes and the water inventories. Additionally, these passive systems impose no significant challenge to the operator. Performance analyses for the 4500 MWth ESBWR were made for a spectrum of LOCA events. These calculations accounted for uncertainties and biases in the computer models and used conservative initial conditions and plant parameters. Results of these performance analyses show that: (1) core remains covered with large margin and there is no core heatup in the ESBWR for any break size, (2) the long-term containment pressure increases gradually with time, in the order of hours, and the peak pressure is below the design value with large margin, and (3) the margins depend on the containment volumes and water inventories. (authors)

Cheung, Y.K.; Shiralkar, B.S.; Marquino, W. [GE Energy, 1989 Little Orchard St., San Jose, CA 95125 (United States)

2006-07-01

338

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

SciTech Connect

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.

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

2003-02-01

339

Inner/outer iterative methods and numerical Schwarz algorithms - II  

SciTech Connect

Variants of the numerical Schwarz algorithms for solving elliptic partial differential equations on multiprocessing systems are described and analyzed. The methods are described in terms of domain decomposition techniques and mathematically cast into an inter/outer matrix iteration form. It is shown that under certain matrix nonnegativity conditions that the convergence rate of the global iteration is invariant to the amount of overlap of the subdomains when one inner iteration is taken.

Rodrigue, G.; Saylor, P.

1985-05-01

340

Simulation and Analysis of the Hybrid Operating Mode in ITER  

SciTech Connect

The hybrid operating mode in ITER is examined with 0D systems analysis, 1.5D discharge scenario simulations using TSC and TRANSP, and the ideal MHD stability is discussed. The hybrid mode has the potential to provide very long pulses and significant neutron fluence if the physics regime can be produced in ITER. This paper reports progress in establishing the physics basis and engineering limitation for the hybrid mode in ITER.

Kessel, C.E.; Budny, R.V.; Indireshkumar, K.

2005-09-22

341

Magnet design technical report---ITER definition phase  

SciTech Connect

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.

Henning, C. (ed.)

1989-04-28

342

A historical overview of iterative methods  

NASA Astrophysics Data System (ADS)

The object of this paper is to present a historical overview of the development of iterative methods for the solution of large sparse systems of linear equations. The emphasis is on methods which are applicable to linear systems arising in the numerical solution of partial differential equations. Aspects to be covered including the methods of L.F. Richardson and of Liebmann as well as relaxation methods used by Southwell and others; the SOR method and extensions such as block SOR methods, and p-cyclic matrices; Chebyshev polynomial methods; alternating direction implicit methods; the SSOR method; approximate matrix factorization methods including the strongly implicit method (SIP) and the incomplete Cholesky method (ICC); fast direct methods; conjugate gradient methods; adaptive methods for the automatic determination of iteration parameters; multigrid methods; methods for nonsymmetric systems; and iterative software. Future developments will be discussed with emphasis on the use of vector and parallel processors.

Young, David M.

1989-05-01

343

Comparison of mode analyses at different resolutions applied to nucleic acid systems.  

PubMed

More than two decades of different types of mode analyses has shown that these techniques can be useful in describing large-scale motions in protein systems. A number of mode analyses are available and include quasiharmonics, classical normal mode, block normal mode, and the elastic network model. Each of these methods has been validated for protein systems and this variety allows researchers to choose the technique that gives the best compromise between computational cost and the level of detail in the calculation. These same techniques have not been systematically tested for nucleic acid systems, however. Given the differences in interactions and structural features between nucleic acid and protein systems, the validity of these techniques in the protein regime cannot be directly translated into validity in the nucleic acid realm. In this work, we investigate the usefulness of the above mode analyses as applied to two RNA systems, i.e., the hammerhead ribozyme and a guanine riboswitch. We show that classical normal-mode analysis can match the magnitude and direction of residue fluctuations from the more detailed, anharmonic technique, quasiharmonic analysis of a molecular dynamics trajectory. The block normal-mode approximation is shown to hold in the nucleic acid systems studied. Only the mode analysis at the lowest level of detail, the elastic network model, produced mixed results in our calculations. We present data that suggest that the elastic network model, with the popular parameterization, is not best suited for systems that do not have a close packed structure; this observation also hints at why the elastic network model has been found to be valid for many globular protein systems. The different behaviors of block normal-mode analysis and the elastic network model, which invoke similar degrees of coarse-graining to the dynamics but use different potentials, suggest the importance of applying a heterogeneous potential function in a robust analysis of the dynamics of biomolecules, especially those that are not closely packed. In addition to these comparisons, we briefly discuss insights into the conformational space available to the hammerhead ribozyme. PMID:16100266

Van Wynsberghe, Adam W; Cui, Qiang

2005-08-12

344

ITER Fusion Energy  

ScienceCinema

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.

345

Iterative Calculations in Excel  

NSDL National Science Digital Library

This web page contains two example spreadsheets using iterative calculations to solve physical models. The two models are for the structure of a planet and the interaction between the Earth and its atmosphere. Instructions for building running the models are provided. These examples come from a paper submitted to the American Journal of Physics.

2009-07-15

346

MLP iterative construction algorithm  

Microsoft Academic Search

The MLP Iterative Construction Algorithm (MICA) designs a Multi-Layer Perceptron (MLP) neural network as it trains. MICA adds Hidden Layer Nodes one at a time, separating classes on a pair-wise basis, until the data is projected into a linear separable space by class. Then MICA trains the Output Layer Nodes, which results in an MLP that achieves 100% accuracy on

Thomas F. Rathbun; Steven K. Rogers; Martin P. Desimio; Mark E. Oxley

1997-01-01

347

More iteration space tiling  

Microsoft Academic Search

Subdividing the iteration space of a loop into blocks or tiles with a fixed maximum size has several advantages. Tiles become a natural candidate as the unit of work for parallel task scheduling. Synchronization between processors can be done between tiles, reducing synchronization frequency (at some loss of potential parallelism). The shape and size of a tile can be optimized

Michael Wolfe

1989-01-01

348

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

SciTech Connect

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.

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

349

ITER SAFETY TASK NID-5D: Operational tritium loss and accident investigation for heat transport and water detritiation systems.  

National Technical Information Service (NTIS)

The task objectives are to: (a) determine major pathways for tritium loss during normal operation of the cooling systems and water detritiation system, (b) estimate operational losses and environmental tritium releases from the heat transport and water de...

K. M. Kalyanam C. Fong M. Moledina A. Natalizio

1995-01-01

350

Effect of neutral transport on ITER divertor performance  

NASA Astrophysics Data System (ADS)

This paper describes the present state of the development of the computational model of the ITER edge plasma. Neutral-neutral collisions and molecular dynamics are introduced into the self-consistent scheme. First results of ITER modelling including these effects indicate that the operational window for the ITER divertor shifts towards higher neutral pressure in the private-flux region, retaining the operational flexibility determined in the previous analyses. This report was prepared as an account of work undertaken within the framework of ITER Transitional Arrangements (ITA). These are conducted by the participants: China, the European Atomic Energy Community, Japan, Korea, the Russian Federation and the United States of America, under the auspices of the International Atomic Energy Agency. The views and opinions expressed herein do not necessarily reflect those of the participants to the ITA, the IAEA or any agency thereof. Dissemination of the information in this paper is governed by the applicable terms of the former ITER EDA Agreement.

Kukushkin, A. S.; Pacher, H. D.; Kotov, V.; Reiter, D.; Coster, D.; Pacher, G. W.

2005-07-01

351

ITER Dynamic Tritium Inventory Modeling Code  

SciTech Connect

A tool for tritium inventory evaluation within each sub-system of the Fuel Cycle of ITER is vital, with respect to both the process of licensing ITER and also for operation. It is very likely that measurements of total tritium inventories may not be possible for all sub-systems, however tritium accounting may be achieved by modeling its hold-up within each sub-system and by validating these models in real-time against the monitored flows and tritium streams between the systems. To get reliable results, an accurate dynamic modeling of the tritium content in each sub-system is necessary. In order to optimize the configuration and operation of the ITER fuel cycle, a dynamic fuel cycle model was developed progressively in the decade up to 2000-2001. As the design for some sub-systems from the fuel cycle (i.e. Vacuum pumping, Neutral Beam Injectors (NBI)) have substantially progressed meanwhile, a new code developed under a different platform to incorporate these modifications has been developed. The new code is taking over the models and algorithms for some subsystems, such as Isotope Separation System (ISS); where simplified models have been previously considered, more detailed have been introduced, as for the Water Detritiation System (WDS). To reflect all these changes, the new code developed inside EU participating team was nominated TRIMO (Tritium Inventory Modeling), to emphasize the use of the code on assessing the tritium inventory within ITER.

Cristescu, Ioana-R. [Forschungszentrum Karlsruhe HVT-TL (Germany); Doerr, L. [NITEK USA Inc. (United States); Busigin, A. [Forschungszentrum Karlsruhe HVT-TL (Germany); Murdoch, D

2005-07-15

352

Recent developments towards ITER 2001 divertor maintenance  

Microsoft Academic Search

One of the key maintenance operations for the ITER tokamak is the remote replacement of its divertor system. The components making up this system are expected to be activated to a level of several hundred gyrations per hour and contaminated with hazardous and\\/or activated dust (beryllium, carbon, tungsten) and tritium. A suite of specialized remote handling (RH) equipment is, therefore,

J. Palmer; M. Siuko; P. Agostini; R. Gottfried; M. Irving; E. Martin; A. Tesini; M. Van Uffelen

2005-01-01

353

Assessment of Tools and Data for System-Level Dynamic Analyses  

SciTech Connect

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 deployments, location of choke points, the key time lags, when benefits can manifest, and how well parts of fuel cycles work together. This report summarizes the readiness of existing Fuel Cycle Technology (FCT) tools and data for conducting dynamic analyses on the range of options. VISION is the primary dynamic analysis tool. Not only does it model mass flows, as do other dynamic system analysis models, but it allows users to explore various potential constraints. The only fuel cycle for which constraints are not important are those in concept advocates PowerPoint presentations; in contrast, comparative analyses of fuel cycles must address what constraints exist and how they could impact performance. The most immediate tool need is extending VISION to the thorium/U233 fuel cycle. Depending on further clarification of waste management strategies in general and for specific fuel cycle candidates, waste management sub-models in VISION may need enhancement, e.g., more on 'co-flows' of non-fuel materials, constraints in waste streams, or automatic classification of waste streams on the basis of user-specified rules. VISION originally had an economic sub-model. The economic calculations were deemed unnecessary in later versions so it was retired. Eventually, the program will need to restore and improve the economics sub-model of VISION to at least the cash flow stage and possibly to incorporating cost constraints and feedbacks. There are multiple sources of data that dynamic analyses can draw on. In this report, 'data' means experimental data, data from more detailed theoretical or empirical calculations on technology performance, and assumptions such as the earliest date a technology can be deployed. The only fuel cycles for which we currently have adequate data are those we are sure we will never build, e.g., a PUREX plant in the U.S. For actual candidates, even for once through LWRs, there remain missing data such as how the fuel cycle would be completed with a geologic repository. The most immediate data needs are probably basic reactor physics data for new concepts and data associated with waste management for anything other than current technology. The readiness of tools and data is fluid and depends on what purposes are envisioned to drive upcoming analyses and further definition of the waste-related characteristics of fuel cycle candidates. Tools and data sets evolve as needs evolve. Thus, much of the document explains that if the FCT program wants a certain type of analysis, then the tools and data needs are as indicated. For example, functions can be treated as either commodities or facilities. Reactors, separation, fuel fabrication, repository are treated as facility types. Other functions such as uranium mining, conversion, enrichment, and waste packaging and non-repository disposal are treated as commodities and therefore not modeled as extensively. In summary, the tools are functional and can answer many fuel cycle questions but some analyses will require that the tools be modified to support those analyses.

Steven J. Piet; Nick R. Soelberg

2011-06-01

354

Precursor Systems Analyses of Automated Highway Systems: Commercial Vehicle and Transit AHS Analysis. Volume 6.  

National Technical Information Service (NTIS)

This document is the final report of the Automated Highway System (AHS). The activities of Commercial Vehicle and Transit AHS Analysis are reported on in this document. This document type is resource materials. This volume is the six in a series. There ar...

F. Bottiger H. D. Chemnitz J. Doorman U. Franke T. Zimmerman Z. Zomotor

1995-01-01

355

Analysis of loss-of-coolant and loss-of-flow accidents in the first wall cooling system of NET\\/ITER  

Microsoft Academic Search

This paper presents the thermal-hydraulic analysis of potential accidents in the first wall cooling system of the Next European Torus or the International Thermonuclear Experimental Reactor. Three ex-vessel loss-of-coolant accidents, two in-vessel loss-of-coolant accidents, and three loss-of-flow accidents have been analyzed using the thermal-hydraulic system analysis code RELAP5\\/MOD3. The analyses deal with the transient thermal-hydraulic behavior inside the cooling systems

E. M. J. Komen; H. Koning

1994-01-01

356

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

PubMed Central

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.

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

2011-01-01

357

Application of Truncated Cosine Series and Iterative Design Techniques to Offset Quadrature Binary Modulation Systems with Experimental Verification Through Surface Acoustic Wave Finite Impulse Response Filter Modulation  

NASA Astrophysics Data System (ADS)

Full response signaling quadrature binary modulation represents a data communications format which has been used in MODEMs, direct sequence spread spectrum, cellular radio and microwave and satellite communications. Full response quadrature binary modulation systems include QPSK, MSK, SFSK and DSFSK. These full response signaling quadrature binary modulation systems are defined in terms of their baseband symbol pulse shapes. These pulse shapes are studied in terms of their effects on modulated signal envelope uniformity, phase continuity and spectral characteristics. The effects of pulse shaping in general on these characteristics and on intersymbol interference (ISI) is reviewed. Alternative approaches to the selection of pulse shapes for full response signaling quadrature binary modulation systems are introduced in the interest of improving modulated signal spectral confinement. These approaches include selecting classical cosine window functions as pulse shapes. Another approach is to apply the classical cosine series window functions as a pulse shape design tool through the selection of coefficients for the series. A final theoretical approach is to apply iterative techniques to the optimization of pulse shape spectral confinement for given confinement bandwidths with respect to modulated signal envelope uniformity. All these approaches are described in detail and theoretical results are illustrated through numerous examples. An RF modulation test bed was prepared for the purpose of experimentally studying the effects of various innovative pulse shapes on modulated signal envelope uniformity and spectra. A Surface Acoustic Wave (SAW) modulation process was adopted for the shaping of modulated stimulus pulses into near ideal RF bursts. This process required that many aspects of SAW modulation filter design be considered. Nine modulation techniques were tested experimentally. These nine systems represented each of the approaches treated theoretically. Experimental modulated pulse shapes, pulse shape spectra and modulated signal characteristics agree very closely with ideal responses. Suggestions for further improvement of SAW modulation systems are given.

Vigil, Armando Juan

1991-07-01

358

Advances in Omics and Bioinformatics Tools for Systems Analyses of Plant Functions  

PubMed Central

Omics and bioinformatics are essential to understanding the molecular systems that underlie various plant functions. Recent game-changing sequencing technologies have revitalized sequencing approaches in genomics and have produced opportunities for various emerging analytical applications. Driven by technological advances, several new omics layers such as the interactome, epigenome and hormonome have emerged. Furthermore, in several plant species, the development of omics resources has progressed to address particular biological properties of individual species. Integration of knowledge from omics-based research is an emerging issue as researchers seek to identify significance, gain biological insights and promote translational research. From these perspectives, we provide this review of the emerging aspects of plant systems research based on omics and bioinformatics analyses together with their associated resources and technological advances.

Mochida, Keiichi; Shinozaki, Kazuo

2011-01-01

359

A novel high-throughput imaging system for automated analyses of avoidance behavior in zebrafish larvae  

PubMed Central

Early brain development can be influenced by numerous genetic and environmental factors, with long-lasting effects on brain function and behavior. The identification of these factors is facilitated by recent innovations in high-throughput screening. However, large-scale screening in whole organisms remains challenging, in particular when studying changes in brain function or behavior in vertebrate model systems. In this study, we present a novel imaging system for high-throughput analyses of behavior in zebrafish larvae. The three-camera system can image twelve multiwell plates simultaneously and is unique in its ability to provide local visual stimuli in the wells of a multiwell plate. The acquired images are converted into a series of coordinates, which characterize the location and orientation of the larvae. The developed imaging techniques were tested by measuring avoidance behaviors in seven-day-old zebrafish larvae. The system effectively quantified larval avoidance and revealed an increased edge preference in response to a blue or red ‘bouncing ball’ stimulus. Larvae also avoid a bouncing ball stimulus when it is counter-balanced with a stationary ball, but do not avoid blinking balls counter-balanced with a stationary ball. These results indicate that the seven-day-old larvae respond specifically to movement, rather than color, size, or local changes in light intensity. The imaging system and assays for measuring avoidance behavior may be used to screen for genetic and environmental factors that cause developmental brain disorders and for novel drugs that could prevent or treat these disorders.

Pelkowski, Sean D.; Kapoor, Mrinal; Richendrfer, Holly A.; Wang, Xingyue; Colwill, Ruth M.; Creton, Robbert

2011-01-01

360

Genomic and Secretomic Analyses Reveal Unique Features of the Lignocellulolytic Enzyme System of Penicillium decumbens  

PubMed Central

Many Penicillium species could produce extracellular enzyme systems with good lignocellulose hydrolysis performance. However, these species and their enzyme systems are still poorly understood and explored due to the lacking of genetic information. Here, we present the genomic and secretomic analyses of Penicillium decumbens that has been used in industrial production of lignocellulolytic enzymes in China for more than fifteen years. Comparative genomics analysis with the phylogenetically most similar species Penicillium chrysogenum revealed that P. decumbens has evolved with more genes involved in plant cell wall degradation, but fewer genes in cellular metabolism and regulation. Compared with the widely used cellulase producer Trichoderma reesei, P. decumbens has a lignocellulolytic enzyme system with more diverse components, particularly for cellulose binding domain-containing proteins and hemicellulases. Further, proteomic analysis of secretomes revealed that P. decumbens produced significantly more lignocellulolytic enzymes in the medium with cellulose-wheat bran as the carbon source than with glucose. The results expand our knowledge on the genetic information of lignocellulolytic enzyme systems in Penicillium species, and will facilitate rational strain improvement for the production of highly efficient enzyme systems used in lignocellulose utilization from Penicillium species.

Qin, Yuqi; Ma, Liang; Li, Jie; Zheng, Huajun; Wang, Shengyue; Wang, Chengshu; Xun, Luying; Zhao, Guo-Ping; Zhou, Zhihua; Qu, Yinbo

2013-01-01

361

Genomic and secretomic analyses reveal unique features of the lignocellulolytic enzyme system of Penicillium decumbens.  

PubMed

Many Penicillium species could produce extracellular enzyme systems with good lignocellulose hydrolysis performance. However, these species and their enzyme systems are still poorly understood and explored due to the lacking of genetic information. Here, we present the genomic and secretomic analyses of Penicillium decumbens that has been used in industrial production of lignocellulolytic enzymes in China for more than fifteen years. Comparative genomics analysis with the phylogenetically most similar species Penicillium chrysogenum revealed that P. decumbens has evolved with more genes involved in plant cell wall degradation, but fewer genes in cellular metabolism and regulation. Compared with the widely used cellulase producer Trichoderma reesei, P. decumbens has a lignocellulolytic enzyme system with more diverse components, particularly for cellulose binding domain-containing proteins and hemicellulases. Further, proteomic analysis of secretomes revealed that P. decumbens produced significantly more lignocellulolytic enzymes in the medium with cellulose-wheat bran as the carbon source than with glucose. The results expand our knowledge on the genetic information of lignocellulolytic enzyme systems in Penicillium species, and will facilitate rational strain improvement for the production of highly efficient enzyme systems used in lignocellulose utilization from Penicillium species. PMID:23383313

Liu, Guodong; Zhang, Lei; Wei, Xiaomin; Zou, Gen; Qin, Yuqi; Ma, Liang; Li, Jie; Zheng, Huajun; Wang, Shengyue; Wang, Chengshu; Xun, Luying; Zhao, Guo-Ping; Zhou, Zhihua; Qu, Yinbo

2013-02-01

362

Iterative learning control of a fully flexible valve actuation system for non-throttled engine load control  

Microsoft Academic Search

This paper presents the application of a fully flexible valve actuation system for non-throttled load control of an internal combustion engine. A novel camless valve actuation system with a unique hydro-mechanical internal feedback mechanism which simplifies the external control design is first introduced. All the critical parameters describing the engine valve event, i.e., lift, timing, duration and seating velocity, can

Adam Heinzen; Pradeep Gillella; Zongxuan Sun

2011-01-01

363

Challenges for Cryogenics at Iter  

NASA Astrophysics Data System (ADS)

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.

Serio, L.

2010-04-01

364

Final Report on ITER Task Agreement 81-18  

SciTech Connect

During 2007, the US International Thermonuclear Experimental Reactor (ITER) Project Office (USIPO) entered into a Task Agreement (TA) with the ITER International Organization (IO) to conduct Research and Development activity and/or Design activity in the area of Safety Analyses. There were four tasks within this TA, which were to provide the ITER IO with: 1) Quality Assurance (QA) documentation for the MELCOR 1.8.2 Fusion code, 2) a pedigreed version of MELCOR 1.8.2, 3) assistance in MELCOR input deck development and accident analyses, and 4) support and assistance in the operation of the MELCOR 1.8.2. This report, which is the final report for this agreement, documents the completion of the work scope under this ITER TA, designated as TA 81-18.

Brad J. Merrill

2008-02-01

365

ITER breeding blanket design  

SciTech Connect

A breeding blanket design has been developed for ITER to provide the necessary tritium fuel to achieve the technical objectives of the Enhanced Performance Phase. It uses a ceramic breeder and water coolant for compatibility with the ITER machine design of the Basic Performance Phase. Lithium zirconate and lithium oxide am the selected ceramic breeders based on the current data base. Enriched lithium and beryllium neutron multiplier are used for both breeders. Both forms of beryllium material, blocks and pebbles are used at different blanket locations based on thermo-mechanical considerations and beryllium thickness requirements. Type 316LN austenitic steel is used as structural material similar to the shielding blanket. Design issues and required R&D data are identified during the development of the design.

Gohar, Y.; Cardella, A.; Ioki, K.; Lousteau, D.; Mohri, K.; Raffray, R.; Zolti, E. [ITER Joint Central Team, Garching (Germany)] [and others

1995-12-31

366

A frequency domain analysis of a second order iterative learning control algorithm  

Microsoft Academic Search

A frequency domain analysis method of a second order iterative learning control (ILC) algorithm is considered. Using the notion of iterative systems bounds for stability are presented in the frequency domain for the second order term. The bounds are found using a geometrical approach based on the special structure of the transfer matrix in the iterative system. Two examples are

M. Norrlof; S. Gunnarsson

1999-01-01

367

Adaptive vibration suppression system: an iterative control law for a piezoelectric actuator shunted by a negative capacitor.  

PubMed

An adaptive system for the suppression of vibration transmission using a single piezoelectric actuator shunted by a negative capacitance circuit is presented. It is known that by using a negative-capacitance shunt, the spring constant of a piezoelectric actuator can be controlled to extreme values of zero or infinity. Because the value of spring constant controls a force transmitted through an elastic element, it is possible to achieve a reduction of transmissibility of vibrations through the use of a piezoelectric actuator by reducing its effective spring constant. Narrow frequency range and broad frequency range vibration isolation systems are analyzed, modeled, and experimentally investigated. The problem of high sensitivity of the vibration control system to varying operational conditions is resolved by applying an adaptive control to the circuit parameters of the negative capacitor. A control law that is based on the estimation of the value of the effective spring constant of a shunted piezoelectric actuator is presented. An adaptive system which achieves a self-adjustment of the negative capacitor parameters is presented. It is shown that such an arrangement allows the design of a simple electronic system which offers a great vibration isolation efficiency under variable vibration conditions. PMID:23221228

Kodejska, Milos; Mokry, Pavel; Linhart, Vaclav; Vaclavik, Jan; Sluka, Tomas

2012-12-01

368

New iterative methods  

Microsoft Academic Search

In this paper, we present a new three-step predictor corrector type iterative method for finding simple and real roots of a non-linear equation in one variable, i.e., f(x)=0. Experiments show that our new method is more efficient than the other known methods. A comparison of the proposed method with other methods reveals that the new method performs better as shown

Arif Rafiq; Sifat Hussain; Farooq Ahmad; Muhammad Awais

2007-01-01

369

Experimental demonstration of non-iterative interpolation-based partial ICI compensation in100G RGI-DP-CO-OFDM transport systems.  

PubMed

We experimentally investigate the performance of a low-complexity non-iterative phase noise induced inter-carrier interference (ICI) compensation algorithm in reduced-guard-interval dual-polarization coherent-optical orthogonal-frequency-division-multiplexing (RGI-DP-CO-OFDM) transport systems. This interpolation-based ICI compensator estimates the time-domain phase noise samples by a linear interpolation between the CPE estimates of the consecutive OFDM symbols. We experimentally study the performance of this scheme for a 28 Gbaud QPSK RGI-DP-CO-OFDM employing a low cost distributed feedback (DFB) laser. Experimental results using a DFB laser with the linewidth of 2.6 MHz demonstrate 24% and 13% improvement in transmission reach with respect to the conventional equalizer (CE) in presence of weak and strong dispersion-enhanced-phase-noise (DEPN), respectively. A brief analysis of the computational complexity of this scheme in terms of the number of required complex multiplications is provided. This practical approach does not suffer from error propagation while enjoying low computational complexity. PMID:22772177

Mousa-Pasandi, Mohammad E; Zhuge, Qunbi; Xu, Xian; Osman, Mohamed M; El-Sahn, Ziad A; Chagnon, Mathieu; Plant, David V

2012-07-01

370

Precursor systems analyses of automated highway systems. Activity area H: AHS roadway deployment analysis. Final report, September 1993-November 1994  

SciTech Connect

The activity addresses highway infrastructure topics that will be encouraged when an automated highway system (AHS) is deployed. AHS right-of-way requirements were analyzed, based on the following criteria: width of AHS vehicle, ability of the system to keep the vehicle on the desired path, barrier width (for dedicated systems), presence or absence of shoulder (breakdown lane), and width of the shoulder. AHS capacity was established by utilizing traffic densities based on platoon sizes, inter-platoon spacings, and intra-platoon spacing. Inter-platoon spacing considered several failure assumptions and the requirement that inter-platoon spacing provide safe braking distances based on the failure assumptions. Based on this analysis, it is concluded that AHS capacities as high as 6,000 vehicles per lane per hour would be feasible. This established the range of capcity used in further Precursor Systems Analyses.

Schulze, R.; Lima, P.; Crowe, E.; O`Brien, S.

1995-05-01

371

Inner\\/outer iterative methods and numerical Schwarz algorithms  

Microsoft Academic Search

Variants of the numerical Schwarz algorithms for solving elliptic partial differential equations on multiprocessing systems are described and analyzed. The methods are described in terms of domain decomposition techniques and mathematically cast into an inter\\/outer matrix iteration form. It is shown that under certain matrix nonnegativity conditions that the convergence rate of the global iteration is invariant to the amount

Garry H. Rodrigue; P. Saylor

1985-01-01

372

Development of a Tritium Extruder for ITER Pellet Injection  

Microsoft Academic Search

As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by

M. J. Gouge; P. W. Fisher

1998-01-01

373

Detailed design of the ITER primary cryopump model  

Microsoft Academic Search

A cryopump as ITER primary vacuum pump is developed at FZK under the European Fusion Technology Programme. The ITER vacuum system comprises 16 cryopumps as primary vacuum pumps operating in a cyclic mode. Prior to the construction of a prototype cryopump, the concept is tested on a reduced-scale model pump. In the present paper the detailed design of the model

N. Petersohqa; J. C. Boissin; D. Murdoch; A. Mack

1997-01-01

374

Analysing sediment storage and landform connectivity using geomorphological mapping and a systems approach (Gradental, Austria)  

NASA Astrophysics Data System (ADS)

Sediment cascades describe macro and mesoscale morphological systems in alpine catchments, however a number of temporal and spatial interactions between variable system components are still poorly understood. This study identifies sediment storage and routing patterns of sediment fluxes using geomorphological mapping and GIS-analyses complementary. Multiple sediment storage- and flux-related landform parameters were mapped during several field campaigns in summer 2009. These include landform types, surface material, particle size, process activity, vegetation cover, input-output relationships, and others. Inaccessible areas (e.g. hanging valleys) were mapped by digital orthophoto-interpretation. Additional morphometric parameters are derived using DEM data. Landform parameters are analyzed using a systems approach to identify sediment stores, cascade structures and landform connectivity that compose the sediment flux system of the Gradental. The study delivers a detailed geomorphological map of the Gradental, and a conceptual model of sediment flux. We will present preliminary results of the mapping campaign and the design and composition of the landform database that forms the basis for storage quantification and sediment budget calculation.

Bellinger, Johannes; Götz, Joachim; Otto, Jan-Christoph; Schrott, Lothar

2010-05-01

375

Sensitivity and uncertainty analysis of nuclear responses in the EU HCLL TBM of ITER  

Microsoft Academic Search

Within the EU Fusion Technology Programme dedicated theoretical and experimental efforts are conducted to provide reliable nuclear data and computational tools for design analyses for fusion devices like ITER including qualified uncertainty estimates. In this respect, the present paper reports on sensitivity and uncertainty analyses for the EU HCLL Test Blanket Module (TBM) of ITER. Neutron flux spectra and tritium

Dieter Leichtle; Ulrich Fischer; Reuven L. Perel; Arkady Serikov

2011-01-01

376

An iterative SVD-tangential interpolation method for medium-scale MIMO systems approximation with application on flexible aircraft  

Microsoft Academic Search

In this paper, the problem of medium-scale MIMO LTI systems approximation is addressed. The proposed methodology, inspired from recent developments in the model reduction community (i.e. [1], [2], [3]), consists of combining the features of the SVD reduction approach with the tangential interpolation ones. The contributions of the paper are in two folds: (i) it provides a simple but numerically

C. Poussot-Vassal

2011-01-01

377

Extending ITER materials design to welded joints  

NASA Astrophysics Data System (ADS)

This paper extends the ITER materials properties documentation to weld metals and incorporates the needs of Test Blanket Modules for higher temperature materials properties. Since the main structural material selected for ITER is type 316L(N)-IG, the paper is focused on weld metals and joining techniques for this steel. Materials properties data are analysed according to the French design and construction rules for nuclear components (RCC-MR) and design allowables are equally derived using the same rules. Particular attention is paid to the type of weld metal, to the type and position of welding and their influence on the materials properties data and design allowables. The primary goal of this work, starting with 19-12-2 weld metal, is to produce comprehensive materials properties documentations that when combined with codification and inspection documents would satisfy ITER licensing needs. As a result, structural stability and capability of welded joints during manufacturing of ITER components and their subsequent service, including the effects of irradiation and eventual incidental or accidental situations, are also covered.

Tavassoli, A.-A. F.

2007-08-01

378

Splittable CS model coil for ITER  

NASA Astrophysics Data System (ADS)

The purpose of the Splittable CS Model Coil is twofold: to test the different conductors proposed for ITER in relevant conditions and to check the manufacturing processes foreseen for the ITER magnets. This model coil consists of a main coil in the shape of a circular solenoid and a single-layer removable insert. An inflatable steel jacket set between the main coil and the insert and a precompression system allows the insert to be put into compression at a stress level comparable to the one projected in the ITER Central Solenoid (CS) when it is used as a central bucking post for the toroidal magnet. The experimentation performed with this CS Model Coil will assess the dependence of the critical current on the imposed external compressive or tensile stress.

Libeyre, P.; Bertrand, B.; Duchateau, J. L.; Torossian, A.; Turck, B.

1994-07-01

379

A hybrid preconditioner of banded matrix approximation and alternating direction implicit iteration for symmetric Sinc–Galerkin linear systems  

Microsoft Academic Search

The symmetric Sinc–Galerkin method applied to a sparable second-order self-adjoint elliptic boundary value problem gives rise to a system of linear equations(?x?Dy+Dx??y)u=g,where? is the Kronecker product symbol, ?x and ?y are Toeplitz-plus-diagonal matrices, and Dx and Dy are diagonal matrices. The main contribution of this paper is to present and analyze a two-step preconditioning strategy based on the banded matrix

Michael K. Ng; Zhong-Zhi Bai

2003-01-01

380

Alternating multiuser detection with iterative soft interference cancellation for highly loaded dual-signaling MIMO CDMA systems  

Microsoft Academic Search

This paper presents an effective multiuser detector (MUD) for the uplink of dual-signaling multiple-input multiple-output (MIMO) code division multiple access (CDMA) systems over multipath fading channels, where the data are transmitted using either the spatially multiplexing (SM) or the space-time block code (STBC) scheme. The new MUD first separates users into two groups according to their transmission signaling schemes and

Yung-Ping Tu; Wen-Hsien Fang; Hoang-Yang Lu

2009-01-01

381

Stream restoration in dynamic fluvial systems: Scientific approaches, analyses, and tools  

NASA Astrophysics Data System (ADS)

In the United States the average annual investment in river restoration programs is approximately $1 billion. Despite this burgeoning industry, the National Water Quality Inventory, which tracks the health of the nation's rivers, has shown no serious improvement in cumulative river health since the early 1990s. In the AGU monograph Stream Restoration in Dynamic Fluvial Systems: Scientific Approaches, Analyses, and Tools, editors Andrew Simon, Sean J. Bennett, and Janine M. Castro pull together the latest evidence-based understanding of stream restoration practices, with an aim of guiding the further development of the field and helping to right its apparently unsuccessful course. In this interview, Eos talks to Sean J. Bennett, University of Buffalo, about the culture, practice, and promise of restoring rivers.

Schultz, Colin

2012-04-01

382

Iterative Berechnung der Totzeit aus Bruttoretentionsdaten  

Microsoft Academic Search

An iterative method for computing gas hold-up time of the GC-system used from known retention indices and non-adjusted retention times of three substances is described. The algorithms used and a program for the Hewlett Packard hp 65 pocket calculator are given.

S. Ebel; R. E. Kaiser

1974-01-01

383

Design of the ITER torus prototype cryopump  

Microsoft Academic Search

Forschungszentrum Karlsruhe (FZK) is developing the ITER prototype torus exhaust pumping system, comprising eight identical cryosorption pumps to provide a high pumping speed and capacity, and fast regeneration. The prototype pump features an integral inlet valve with a nominal diameter of 800mm which can be closed during the plasma pulse operation for on-line regeneration. The pump design is incorporating the

V. Hauer; J.-C. Boissin; Chr. Day; H. Haas; A. Mack; D. Murdoch; R. Lässer; M. Wykes

2007-01-01

384

Nonlinear response analyses of a soil–structure interaction system using transformed energy transmitting boundary in the time domain  

Microsoft Academic Search

The energy transmitting boundary used in programs such as FLUSH and ALUSH is a very accurate and useful technique for the earthquake response analysis of soil–structure interaction systems. However, it is applicable only to linear analyses or equivalent linear analyses, because it can be calculated only in the frequency domain. The author has proposed methods for transforming frequency-dependent impedance into

Naohiro Nakamura

2009-01-01

385

Initial reaction kinetics of succinate dehydrogenase in mouse liver studied with a real-time image analyser system  

Microsoft Academic Search

The initial reaction kinetics of succinate dehydrogenase in situ were investigated in sections of mouse unfixed liver using an ARGUS-100 image analyser system. The sections were incubated on substrate-containing agarose gel films. Images of a section, illuminated with monochromatic light (584 nm), were captured with the image analyser in real time at intervals of 10 s during the incubation. The

Y. Nakae; P. J. Stoward

1992-01-01

386

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

NASA Astrophysics Data System (ADS)

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.

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

2008-01-01

387

A fast iterative method for discretized Volterra-Fredholm integral equations  

NASA Astrophysics Data System (ADS)

Solving the nonlinear systems arising in the discretization in space and time of Volterra-Fredholm integral equations by Newton iteration leads to dense linear systems whose dimension depends on the spatial mesh. The solution of these linear systems can hence be very costly. Here we try to reduce these costs by solving each Newton iteration by a non-stationary inner iteration process. Each inner iteration again requires the solution of a linear system. However, since the splitting matrix is diagonal, now the components or sets of components can be computed in parallel. The performance of this iteration method is illustrated by means of a few significative examples.

Cardone, A.; Messina, E.; Russo, E.

2006-05-01

388

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

SciTech Connect

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 (50,000 kg/day or larger) and forecourt plant designs for distributed production and delivery at about 1,500 kg/day. The HYSYS software inherently ensures mass and energy balances across all components and it includes thermodynamic data for all chemical species. The optimized designs described in this report are based on analyses of process flow diagrams that included realistic representations of fluid conditions and component efficiencies and operating parameters for each of the HTE hydrogen production configurations analyzed. As with previous HTE system analyses performed at the INL, a custom electrolyzer model was incorporated into the overall process flow sheet. This electrolyzer model allows for the determination of the average Nernst potential, cell operating voltage, gas outlet temperatures, and electrolyzer efficiency for any specified inlet steam, hydrogen, and sweep-gas flow rates, current density, cell active area, and external heat loss or gain. The lifecycle cost analyses were performed using the H2A analysis methodology developed by the Department of Energy (DOE) Hydrogen Program. This methodology utilizes spreadsheet analysis tools that require detailed plant performance information (obtained from HYSYS), along with financial and cost information to calculate lifecycle costs. There are standard default sets of assumptions that the methodology uses to ensure consistency when comparing the cost of different production or plant design options. However, these assumptions may also be varied within the spreadsheets when better information is available or to allow the performance of sensitivity studies. The selected reference plant design for this study was a 1500 kg/day forecourt hydrogen production plant operating in the thermal-neutral mode. The plant utilized industrial natural gas-fired heaters to provide process heat, and grid electricity to supply power to the electrolyzer modules and system components. Modifications to the reference design included replacing the gas-fired heaters with electric resistance heaters, changing the operating mode of the electrolyzer (to operate below the thermal-neutral voltage), and considering a larger 50,000 kg/day central hydrogen production plant design. Total H2A-calculated hydrogen production costs for the reference 1,500 kg/day forecourt hydrogen production plant were $3.42/kg. The all-electric plant design using electric resistance heaters for process heat, and the reference design operating below the thermal-neutral voltage had calculated lifecycle hydrogen productions costs of $3.55/kg and $5.29/kg, respectively. Because of its larger size and associated economies of scale, the 50,000 kg/day central hydrogen production plant was able to produce hydrogen at a cost of only $2.89/kg.

Edwin A. Harvego; James E. O'Brien; Michael G. McKellar

2012-05-01

389

Using a systems engineering process to develop engineered barrier system design concepts  

Microsoft Academic Search

The methodology used to develop conceptual designs of the engineered barrier system and waste packages for a geologic repository is based on an iterative systems engineering process. The process establishes a set of general mission requirements and then conducts detailed requirements analyses using functional analyses, system concept syntheses, and trade studies identifications to develop preliminary system concept descriptions. The feasible

L. J. Jardine; D. W. Short

1991-01-01

390

PFB Coal Fired Combined Cycle Development Program. System Analyses and Trade-Offs (Task 1.3).  

National Technical Information Service (NTIS)

The systems analyses and optimization studies performed in connection with a program to design and evaluate a commercial 663 MWe coal-fired combined cycle power plant using pressurized fluidized bed combustion and advanced technology in the hot gas cleanu...

1981-01-01

391

Requirements for ITER diagnostics  

SciTech Connect

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.

Young, K.M.

1991-01-01

392

Development of a fast multi-parameter data acquisition system for microbeam analyses  

NASA Astrophysics Data System (ADS)

A commercially available Personal Computer (PC)-based multi-parameter data acquisition system has been developed for ion microbeam analyses. The PC is equipped with a recent fast processor, a large volume of memory and a general multi-channel Analogue to Digital Converter (ADC) interface board. When a signal from an X-ray detector (PIXE), from a particle detector (RBS) or from others triggers this ADC for data acquisition, X-Y beam scanning control signals which indicate the beam position are also digitized at the same time. These data are addressed to the 3D matrices in the memory space, that consist of 1024 channels for the energy spectra and 150x150 pixels for corresponding the beam scan area. Real time data processing can be done in addition to this data acquisition by the fast processor with the large memory. Simultaneous PIXE and RBS elemental mapping and ion beam induced charge (IBIC) imaging on fine structure diodes have been demonstrated with this system.

Sakai, T.; Hamano, T.; Hirao, T.; Kamiya, T.; Murozono, K.; Inoue, J.; Matsuyama, S.; Iwasaki, S.; Ishii, K.

1998-03-01

393

Predicting US summer precipitation using NCEP Climate Forecast System version 2 initialized by multiple ocean analyses  

NASA Astrophysics Data System (ADS)

This study examines the prediction skill of the contiguous United States (CONUS) precipitation in summer, as well as its potential sources using a set of ensemble hindcasts conducted with the National Centers for Environmental Prediction (NCEP) Climate Forecast System version 2 and initialized from four independent ocean analyses. The multiple ocean ensemble mean (MOCN_ESMEAN) hindcasts start from each April for 26 summers (1982-2007), with each oceanic state paired with four atmosphere-land states. A subset of hindcasts from the NCEP CFS Reanalysis and Reforecast (CFSRR) project for the same period, from the same initial month and with the same total ensemble size, is also analyzed. Compared with CFSRR, MOCN_ESMEAN is distinguished by its oceanic ensemble spread that introduces potentially larger perturbations and better spatial representation of the oceanic uncertainty. The prediction skill of the CONUS precipitation in summer shows a similar spatial pattern in both MOCN_ESMEAN and CFSRR, but the results suggested that initialization from multiple ocean analyses may bring more robust signals and additional skills to the seasonal prediction for both sea surface temperature and precipitation. Among the predictable areas for precipitation, the northwestern CONUS (NWUS) is the most robust. A further analysis shows that the enhanced summer precipitation prediction skill in NWUS is mainly associated with the El Niño/Southern Oscillation, with possible influence also from the Pacific Decadal Oscillation. Through this work, we argue that a large ensemble is necessary for precipitation forecast in mid-latitudes, such as the CONUS, and taking into account of the oceanic initial state uncertainty is an efficient way to build such an ensemble.

Zhu, Jieshun; Huang, Bohua; Hu, Zeng-Zhen; Kinter, James L.; Marx, Lawrence

2013-10-01

394

Predicting US summer precipitation using NCEP Climate Forecast System version 2 initialized by multiple ocean analyses  

NASA Astrophysics Data System (ADS)

This study examines the prediction skill of the contiguous United States (CONUS) precipitation in summer, as well as its potential sources using a set of ensemble hindcasts conducted with the National Centers for Environmental Prediction (NCEP) Climate Forecast System version 2 and initialized from four independent ocean analyses. The multiple ocean ensemble mean (MOCN_ESMEAN) hindcasts start from each April for 26 summers (1982-2007), with each oceanic state paired with four atmosphere-land states. A subset of hindcasts from the NCEP CFS Reanalysis and Reforecast (CFSRR) project for the same period, from the same initial month and with the same total ensemble size, is also analyzed. Compared with CFSRR, MOCN_ESMEAN is distinguished by its oceanic ensemble spread that introduces potentially larger perturbations and better spatial representation of the oceanic uncertainty. The prediction skill of the CONUS precipitation in summer shows a similar spatial pattern in both MOCN_ESMEAN and CFSRR, but the results suggested that initialization from multiple ocean analyses may bring more robust signals and additional skills to the seasonal prediction for both sea surface temperature and precipitation. Among the predictable areas for precipitation, the northwestern CONUS (NWUS) is the most robust. A further analysis shows that the enhanced summer precipitation prediction skill in NWUS is mainly associated with the El Niño/Southern Oscillation, with possible influence also from the Pacific Decadal Oscillation. Through this work, we argue that a large ensemble is necessary for precipitation forecast in mid-latitudes, such as the CONUS, and taking into account of the oceanic initial state uncertainty is an efficient way to build such an ensemble.

Zhu, Jieshun; Huang, Bohua; Hu, Zeng-Zhen; Kinter, James L.; Marx, Lawrence

2013-05-01

395

Searching with iterated maps  

PubMed Central

In many problems that require extensive searching, the solution can be described as satisfying two competing constraints, where satisfying each independently does not pose a challenge. As an alternative to tree-based and stochastic searching, for these problems we propose using an iterated map built from the projections to the two constraint sets. Algorithms of this kind have been the method of choice in a large variety of signal-processing applications; we show here that the scope of these algorithms is surprisingly broad, with applications as diverse as protein folding and Sudoku.

Elser, V.; Rankenburg, I.; Thibault, P.

2007-01-01

396

Study of the Load Resilient External Matching Circuit for the ITER ICRH/FWCD System by means of its Mock-up  

SciTech Connect

The reference matching solution for ITER grouping the 24 straps of the ITER antenna array in 4 'conjugate T' (CT) circuits through pre-matching network is investigated starting from the S matrix measurements versus antenna loading made on the mock-up of the original design. Six decouplers alleviate the mutual coupling effects between the 4 matching circuits and their power sources. All matching actuators are outside the antenna plug. The matching procedure allows the control of load resilience and plasma excitation spectrum for heating and current drive.

Messiaen, A.; Dumortier, P.; Lamalle, P. U.; Vervier, M. [Plasma Physics Laboratory, Association EURATOM--Belgian State, Partner in TEC, Royal Military Academy, Brussels (Belgium)

2007-09-28

397

Constrained block-iterative Landweber scheme for image reconstruction  

NASA Astrophysics Data System (ADS)

The Landweber method provides a framework to formulate iterative algorithms for image reconstruction problems with large, sparse and unstructured system matrices. In a previous study, the authors established the convergence conditions for a general Landweber scheme in both simultaneous and block-iterative [or ordered-subset (OS)] formats with either consistent or inconsistent data, without constraints. Constrained iterative algorithms provide a mechanism for incorporating prior knowledge such nonnegativity, bounds, finite spatial or spectral supports, etc. Hence, they have been widely used in practice. Although the simultaneous constrained (or projected) Landweber scheme was well studied, the convergence of the constrained block-iterative Landweber scheme is unknown. Block-iterative schemes are recently intensively studied theoretically and applied widely. In this paper, we report convergence conditions of a constrained block-iterative Landweber scheme. Prior knowledge is represented as convex sets in which an image of interest must stay. The constrained block-iterative Landweber scheme is constructed by alternatively performing a projection onto convex sets (POCS) and a conventional block-iterative Landweber iteration. The POCS method has been used before for constrained image reconstruction to satisfy both imaging equations and convex constraints. Our approach is different from the conventional application of the POCS method in that we use Landweber iteration for the imaging equations and perform POCS only for the convex constraints. While the conventionally applied POCS method requires Moore-Penrose inverses of matrix blocks, our constrained block-iterative method only takes transposes of such matrix blocks, and improves the computational complexity greatly.

Jiang, Ming; Wang, Ge

2004-10-01

398

The design and development of divertor remote handling equipment for ITER  

Microsoft Academic Search

A key ITER maintenance activity is the complete exchange of the divertor system at scheduled intervals, typically after every 3–4 years of plasma operations. ITER divertor replacement is classified as a remote handling (RH) Class 1 activity and as such, detailed design of the associated equipment and verification of its operation before ITER construction by way of prototypes and mock-ups,

J. Palmer; M. Irving; J. Järvenpää; H. Mäkinen; H. Saarinen; M. Siuko; A. Timperi; S. Verho

2007-01-01

399

Drought Analyses of the California Central Valley Surface-Groundwater-Conveyance System  

NASA Astrophysics Data System (ADS)

Historically, California has experienced periods of long drought conditions. Isotopic analyses have indicated that naturally occurring droughts were most pronounced during the 15th century, when S.F. Delta inflows were less than 50 percent of the long term mean flows. During the last 150 years there has been an above average mean flow concurrent with the onset of agricultural development. More importantly, is the advancement of the California water conveyance system and irrigation farming that came into existence during the latter half of the 20th century. This was during a period of historically wet conditions, and until recently, water resource managers have relied on stationary conditions as part of their management strategy. To provide water resources decision makers with the tools needed for better understanding the consequences of persistent droughts, we have begun a series of numerical investigations to determine system behavior and economic impacts under a range of conditions. Our investigations of California Central Valley impacts of sustained droughts are based on a series of specified reductions (10 to 70 percent) in net surface flows for periods ranging from 10 to 60 years and applied to the California Department of Water Resources' California Central Valley Simulation Model (C2VSIM). This simplified methodology represents a means to evaluate the impacts of reductions in net surface flow from reservoirs. The goals of this study are to understand how reductions in surface water are handled within C2VSIM, how groundwater pumping compensates the reduced inflow, to what degree the water table is reduced, and how this system recovers. Pumping costs will also be calculated for each case. Finally, an economic analysis of the impacts on agriculture as related to changes in farming practices that may be needed to maintain a sustainable agricultural economy in the Central Valley under the range of imposed drought conditions is presented.

Miller, N. L.; Dale, L. L.; Vicuna, S. D.

2006-12-01

400

Advances in iterative multigrid PIV image processing  

NASA Astrophysics Data System (ADS)

An image-processing technique is proposed, which performs iterative interrogation of particle image velocimetry (PIV) recordings. The method is based on cross-correlation, enhancing the matching performances by means of a relative transformation between the interrogation areas. On the basis of an iterative prediction of the tracers motion, window offset and deformation are applied, accounting for the local deformation of the fluid continuum. In addition, progressive grid refinement is applied in order to maximise the spatial resolution. The performances of the method are analysed and compared with the conventional cross correlation with and without the effect of a window discrete offset. The assessment of performance through synthetic PIV images shows that a remarkable improvement can be obtained in terms of precision and dynamic range. Moreover, peak-locking effects do not affect the method in practice. The velocity gradient range accessed with the application of a relative window deformation (linear approximation) is significantly enlarged, as confirmed in the experimental results.

Scarano, F.; Riethmuller, M. L.

2000-12-01

401

Advances in iterative multigrid PIV image processing  

NASA Astrophysics Data System (ADS)

An image-processing technique is proposed, which performs iterative interrogation of particle image velocimetry (PIV) recordings. The method is based on cross-correlation, enhancing the matching performances by means of a relative transformation between the interrogation areas. On the basis of an iterative prediction of the tracers motion, window offset and deformation are applied, accounting for the local deformation of the fluid continuum. In addition, progressive grid refinement is applied in order to maximise the spatial resolution. The performances of the method are analysed and compared with the conventional cross correlation with and without the effect of a window discrete offset. The assessment of performance through synthetic PIV images shows that a remarkable improvement can be obtained in terms of precision and dynamic range. Moreover, peak-locking effects do not affect the method in practice. The velocity gradient range accessed with the application of a relative window deformation (linear approximation) is significantly enlarged, as confirmed in the experimental results.

Scarano, F.; Riethmuller, M. L.

402

ITER Activities in Japan  

SciTech Connect

Japanese contributions to ITER engineering design activities are presented, together with an introduction of the objectives and design of the ITER, whose program has been carried out through international collaboration by the European Union, Japan, Russian Federation, and the United States. New technologies have been produced through the development, fabrication, and testing of scalable models in the fields of superconducting magnets, reactor structures with vacuum vessels, remote-maintenance machines, high-heat-flux plasma facing components, neutral beam injectors, high-power millimetre-wave generators, etc. As major contributions from Japan, development and testing results of a 13-T, 640-MJ, Nb{sub 3}Sn pulsed magnet; an 18-deg sector of a vacuum vessel with a height of 15 m and a width of 9 m; CFC armor for a CuCrZr cooling tube that withstood 20 MW/m{sup 2}; a 31 mA/cm{sup 2} negative ion beam source; a 1-MeV beam accelerator; and a 1-MW 170-GHz gyrotron are described.

Tsunematsu, Toshihide; Seki, Masahiro; Tsuji, Hiroshi; Okuno, Kiyoshi; Kato, Takashi; Shibanuma, Kiyoshi; Hanada, Masaya; Watanabe, Kazuhiro; Sakamoto, Keishi; Imai, Tsuyoshi; Ezato, Koichiro; Akiba, Masato [Japan Atomic Energy Research Institute (Japan)

2002-07-15

403

Distinct signaling roles of ceramide species in yeast revealed through systematic perturbation and systems biology analyses.  

PubMed

Ceramide, the central molecule of sphingolipid metabolism, is an important bioactive molecule that participates in various cellular regulatory events and that has been implicated in disease. Deciphering ceramide signaling is challenging because multiple ceramide species exist, and many of them may have distinct functions. We applied systems biology and molecular approaches to perturb ceramide metabolism in the yeast Saccharomyces cerevisiae and inferred causal relationships between ceramide species and their potential targets by combining lipidomic, genomic, and transcriptomic analyses. We found that during heat stress, distinct metabolic mechanisms controlled the abundance of different groups of ceramide species and provided experimental support for the importance of the dihydroceramidase Ydc1 in mediating the decrease in dihydroceramides during heat stress. Additionally, distinct groups of ceramide species, with different N-acyl chains and hydroxylations, regulated different sets of functionally related genes, indicating that the structural complexity of these lipids produces functional diversity. The transcriptional modules that we identified provide a resource to begin to dissect the specific functions of ceramides. PMID:24170935

Montefusco, David J; Chen, Lujia; Matmati, Nabil; Lu, Songjian; Newcomb, Benjamin; Cooper, Gregory F; Hannun, Yusuf A; Lu, Xinghua

2013-10-29

404

Fault and event tree analyses for process systems risk analysis: uncertainty handling formulations.  

PubMed

Quantitative risk analysis (QRA) is a systematic approach for evaluating?likelihood, consequences, and risk of adverse events. QRA based on event (ETA) and fault tree analyses (FTA) employs two basic assumptions. The first assumption is related to?likelihood?values of input events, and the second assumption is regarding interdependence among the events (for ETA) or basic events (for FTA). Traditionally, FTA and ETA both use crisp probabilities; however, to deal with uncertainties, the probability distributions of input event?likelihoods?are assumed. These probability distributions are often hard to come by and even if available, they are subject to incompleteness (partial ignorance) and imprecision. Furthermore, both FTA and ETA assume that events (or basic events) are independent. In practice, these two assumptions are often unrealistic. This article focuses on handling uncertainty in a QRA framework of a process system. Fuzzy set theory and evidence theory are used to describe the uncertainties in the input event?likelihoods. A method based on a dependency coefficient is used to express interdependencies of events (or basic events) in ETA and FTA. To demonstrate the approach, two case studies are discussed. PMID:20731791

Ferdous, Refaul; Khan, Faisal; Sadiq, Rehan; Amyotte, Paul; Veitch, Brian

2010-08-19

405

Electromagnetic and structural analyses of electric gun and integrated launch package systems  

Microsoft Academic Search

The authors describe electromagnetic and structural analyses of electric gun and integrated launch packages. Models presented were developed for the Sabot Launched Electric Gun Kinetic Energy projectile (SLEKE) program and the Cannon Caliber Electromagnetic Launcher (CCEML) program. Analyses were three-dimensional, transient and coupled with thermal calculations including dynamic material properties. In the SLEKE analysis section, the authors focus on the

H. D. Yun; J. H. Price

1995-01-01

406

Iterative Learning in Ballistic Control  

Microsoft Academic Search

In this paper, we formulate and explore the characteristics of iterative learning in ballistic control problems. The ILC theory provides a suitable framework for derivations and analysis of ballistic control under learning process. To overcome the obstacles caused by uncertain gradient and redundant control input, we incorporate extra trials into iterative learning. With the help of trial results, proper control

Jian-Xin Xu; Wei Wang; Deqing Huang

2007-01-01

407

SCALE: a modular code system for performing standardized computer analyses for licensing evaluation. Book I. Volume 1. Control modules  

Microsoft Academic Search

This manual provides documentation for a new, multi faceted computational system called SCALE (Standardized Computer Analyses for Licensing Evaluation) that has been developed to provide a standard analysis tool for use by the NRC staff and licensees in evaluating nuclear fuel facility and package designs. The SCALE system consists of several automated analytical sequences (control modules) which perform criticality, shielding,

Bucholz

1981-01-01

408

Experiments with Iterative Methods for Solving the Discrete Poisson Equation.  

National Technical Information Service (NTIS)

Several fast iterative methods for solving systems of linear equations resulting from the finite difference approximation in elliptic partial differential equations were compared using the relatively simple problem of solving the Poisson equation with Dir...

S. J. Bijlsma R. J. Hoogendoorn

1979-01-01

409

Development of a Tritium Extruder for ITER Pellet Injection.  

National Technical Information Service (NTIS)

As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hyd...

M.J. Gouge P.W. Fisher

1998-01-01

410

US ITER background summary papers  

SciTech Connect

The following brief summaries were prepared by members of the US ITER Home Team to provide background information on the ITER CDA design and in several instances to provide personal observations and suggestions regarding continuation of the ITER Conceptual Design Activities (CDA) into the Engineering Design Activities (EDA). The subjects covered represent areas and issues recognized to be important during the CDA and judged important to the initiation and implementation of the ITER EDA. These summaries were prepared to provide a very condensed statement on each issue to permit the reader to grasp quickly the essential material from the CDA based on the judgment of the author. In several instances, the authors also include suggestions regarding the EDA efforts. References to the appropriate ITER documents are included where the reader can find more detail on each subject.

Doggett, J.N. [comp.] [Lawrence Livermore National Lab., CA (United States); Flanagan, C.A. [comp.] [Oak Ridge National Lab., TN (United States); Post, D.E. [comp.] [Princeton Univ., NJ (United States). Plasma Physics Lab.; Wesley, J.C. [comp.] [General Atomics, San Diego, CA (United States)

1991-05-01

411

Hedgerow planting analysed as a social system--interaction between farmers and other actors in Denmark.  

PubMed

In a number of European countries, including Denmark, the practice of planting hedgerows has a long tradition, and hedgerows form significant structures of semi-natural elements in a matrix of arable land. In Denmark an institutionalised framework has developed in relation to a subsidy scheme encouraging farmers to plant hedgerows. This article analyses the planting practice as a social system; giving emphasis to the interactions between actors and how this affects the current planting activity. Combining an overall description of the nationwide network with a detailed case study in Jutland, Denmark enables an understanding of how the local planting practice is influenced by the local context and the nationwide network, and at the same time contributes to the reproduction of the entire network. It is concluded that the planting activity is characterised by routines, professionalism and division of labour. The local actors involved perceive the activity as a success, and do not question current practise. However, the actors are not aware of the potential consequences of the planting practice at the landscape scale. Even though hedgerows are planted through so-called planting associations related to defined local areas the placement of hedgerows is not co-ordinated and evaluated at a landscape scale. In addition, the composition of hedgerows is standardised at a national level, and the individual farmer makes few adjustments. Thus, the sense of local landscape identity may become blurred. The increasing public attention towards a multiplicity of functions in the agricultural landscape implies further development of the potential positive landscape effects of hedgerows in a local context. This may induce changes in the relationships between actors and eventually the planting practice. PMID:12781756

Busck, Anne Gravsholt

2003-06-01

412

System and Cost Analyses of Broad-Band Fiber Loop Architectures  

Microsoft Academic Search

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

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

1990-01-01

413

COMPARATIVE TRANSIENT ANALYSES OF ACCELERATOR DRIVEN SYSTEMS WITH MIXED OXIDE AND ADVANCED FERTILE FREE FUELS  

Microsoft Academic Search

Comparative safety analyses and investigations have been performed for a small scale ADS with conventional MOX fuel and 800 MWth power class ADTs with advanced fertile free fuels, both cooled by Pb\\/Bi. The analyses cover perturbations of the source, as e.g. unprotected transient over current (UTOC) and beam interruptions as well as perturbations on the core side, protected\\/unprotected transient over

N. Chen; T. Suzuki; A. Rineiski; C. Matzerath Boccaccini; E. Wiegner; W. Maschek

414

Fast, scalable master equation solution algorithms. IV. Lanczos iteration with diffusion approximation preconditioned iterative inversion  

NASA Astrophysics Data System (ADS)

In this paper we propose a second linearly scalable method for solving large master equations arising in the context of gas-phase reactive systems. The new method is based on the well-known shift-invert Lanczos iteration using the GMRES iteration preconditioned using the diffusion approximation to the master equation to provide the inverse of the master equation matrix. In this way we avoid the cubic scaling of traditional master equation solution methods while maintaining the speed of a partial spectral decomposition. The method is tested using a master equation modeling the formation of propargyl from the reaction of singlet methylene with acetylene, proceeding through long-lived isomerizing intermediates.

Frankcombe, Terry J.; Smith, Sean C.

2003-12-01

415

Plasma-surface interaction issues of an all-metal ITER  

NASA Astrophysics Data System (ADS)

We assess key plasma-surface interaction issues of an all-metal plasma facing component (PFC) system for ITER, in particular a tungsten divertor, and a beryllium or tungsten first wall. Such a system eliminates problems with carbon divertor erosion and T/C codeposition, and for an all-tungsten system would better extrapolate to post-ITER devices. The issues studied are sputtering, transport and formation of mixed surface layers, tritium codeposition, plasma contamination, edge-localized mode (ELM) response and He-on-W irradiation effects. Code package OMEGA computes PFC sputtering erosion/redeposition in an ITER full power D-T plasma with convective edge transport. The HEIGHTS package analyses plasma transient response. PISCES and other data are used with code results to assess PFC performance. Predicted outer-wall sputter erosion rates are acceptable for Be (0.3 nm s-1) or bare (stainless steel/Fe) wall (0.05 nm s-1) for the low duty factor ITER, and are very low (0.002 nm s-1) for W. T/Be codeposition in redeposited wall material could be significant (~2 gT/400 s-ITER pulse). Core plasma contamination from wall sputtering appears acceptable for Be (~2%) and negligible for W (or Fe). A W divertor has negligible sputter erosion, plasma contamination and T/W codeposition. Be can grow at/near the strike point region of a W divertor, but for the predicted maximum surface temperature of ~800 °C, deleterious Be/W alloy formation as well as major He/W surface degradation will probably be avoided. ELMs are a serious challenge to the divertor, but this is true for all materials. We identify acceptable ELM parameters for W. We conclude that an all-metal PFC system is likely a much better choice for ITER D-T operation than a system using C. We discuss critical R&D needs, testing requirements, and suggest employing a 350-400 °C baking capability for T/Be reduction and using a deposited tungsten first wall test section.

Brooks, J.N.; Allain, J.P.; Doerner, R.P.; Hassanein, A.; Nygren, R.; Rognlien, T.D.; Whyte, D.G.

2009-03-01

416

U.S. ITER limiter module design  

SciTech Connect

The recent U.S. effort on the ITER (International Thermonuclear Experimental Reactor) shield has been focussed on the limiter module design. This is a multi-disciplinary effort that covers design layout, fabrication, thermal hydraulics, materials evaluation, thermomechanical response, and predicted response during off-normal events. The results of design analyses are presented. Conclusions and recommendations are also presented concerning the capability of the limiter modules to meet performance goals and to be fabricated within design specifications using existing technology. 8 refs., 5 figs., 1 tab.

Mattas, R.F.; Billone, M.; Hassanein, A. [Argonne National Lab., IL (United States)] [and others

1996-12-31

417

Precursor Systems Analyses of Automated Highway Systems. Knowledge Based Systems and Learning Methods for AHS. Volume 10.  

National Technical Information Service (NTIS)

Managing each AHS vehicle and the AHS system as a whole is an extremely complex yndertaking. The authors have investigated and now report on Artificial Intelligence (AI) approaches that can help. In particular, we focus on AI technologies known as Knowled...

J. Schmoltz A. Blumer J. Noonan D. Shedd J. Twarog K. Assiter

1995-01-01

418

ITER: burning plasma physics experiment  

NASA Astrophysics Data System (ADS)

The ITER project has an overall programmatic objective `to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes'. The ITER tokamak design is the embodiment of the finding, endorsed by all the parties to the project, that `the full non-linear interplay between alpha-particle heating, confinement barriers and pressure and profile control, and their compatibility with a divertor can be addressed only in an integrated step'. This step involves not only the study of fusion burning plasma physics but also the demonstration of key items of fusion reactor technology. This paper introduces: magnetic fusion plasma (section 1), the physics goals of ITER (section 2) and the burning plasma physics which will be studied (section 3), examines the present ITER design and how it meets the plasma performance requirements in terms of extended burn at specific fusion power amplification (section 4), describes plasma measurements for ITER and some of the issues involved in their implementation (section 5), indicates how ITER provides a focus for international research into tokamak plasma physics (section 6), and presents a brief report on the status of the ITER Project (section 7). To conclude, this paper presents some final remarks (section 8).

Green, B. J.; ITER International Team; Participant Teams

2003-05-01

419

Numerical solutions of nonlinear evolution equations using variational iteration method  

NASA Astrophysics Data System (ADS)

The variational iteration method is used to solve three kinds of nonlinear partial differential equations, coupled nonlinear reaction diffusion equations, Hirota-Satsuma coupled KdV system and Drinefel'd-Sokolov-Wilson equations. Numerical solutions obtained by the variational iteration method are compared with the exact solutions, revealing that the obtained solutions are of high accuracy. He's variational iteration method is introduced to overcome the difficulty arising in calculating Adomian polynomial in Adomian method. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in mathematical physics.

Soliman, A. A.; Abdou, M. A.

2007-10-01

420

Krylov iterative methods and synthetic acceleration for transport in binary statistical media  

SciTech Connect

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.

Fichtl, Erin D [Los Alamos National Laboratory; Warsa, James S [Los Alamos National Laboratory; Prinja, Anil K [Los Alamos National Laboratory

2008-01-01

421

Videourodynamic and sphincter motor unit potential analyses in Parkinson's disease and multiple system atrophy  

PubMed Central

OBJECTIVES—Urinary dysfunction is a prominent autonomic feature in Parkinson's disease (PD) and multiple system atrophy (MSA), which is not only troublesome but also a cause of morbidity in these disorders. Recent advances in investigative uroneurology offer a better insight into the underlying pathophysiology and appropriate management for urinary dysfunction.?METHODS—twenty one patients with PD (15 men, six women, mean age 64 (49-76), mean disease duration 4 years (1-8 years), median Hoehn and Yahr grade 3 (1-4), all taking 300 mg/day of levodopa (100-500 mg)) and 15 with MSA (eight men, seven women, mean age 59 (48-72), mean disease duration 3 years (0.5-6 years)) were recruited. Videourodynamic and sphincter motor unit potential analyses in the patients with PD and MSA were carried out, looking for distinguishing hallmarks that might be useful in the differential diagnosis of these two diseases.?RESULTS—Urinary symptoms were found in 72% of patients with PD and in 100% with MSA. Filling phase abnormalities in the videourodynamic study included detrusor hyperreflexia in 81% of patients with PD and 56% with MSA, and uninhibited external sphincter relaxation in 33% of patients with PD and 33% of those with MSA. However, open bladder neck at the start of filling was not seen in patients with PD but was present in 53% of those with MSA, suggestive of internal sphincter denervation. Sphincter motor unit potential analysis showed neurogenic motor unit potentials in 5% of patients with PD and in 93% of those with MSA, suggestive of external sphincter denervation. On voiding, detrusor-external sphincter dyssynergia was not seen in patients with PD but was present in 47% of those with MSA. Pressure-flow analysis showed that the Abrams-Griffiths number, a grading of urethral obstruction (outflow obstruction >40), in PD (40 in women and 43 in men) was larger than that in MSA (12 in women and 28 in men). Weak detrusor in PD (66% of women and 40% of men) was less common than that in MSA (71% of women and 63% of men). Postmicturition residuals >100 ml were absent in patients with PD but were present in 47% of patients with MSA.?CONCLUSION—Patients with PD had less severe urinary dysfunction with little evidence of internal or external sphincter denervation, by contrast with the common findings in MSA. The findings of postmicturition residuals >100 ml, detrusor-external sphincter dyssynergia, open bladder neck at the start of bladder filling, and neurogenic sphincter motor unit potentials are highly suggestive of MSA.??

Sakakibara, R; Hattori, T; Uchiyama, T; Yamanishi, T

2001-01-01

422

Issues from activation\\/dose rates calculation for full W ITER machine and increased fluence  

Microsoft Academic Search

The paper presents and discusses the results of the activation calculations for ITER to investigate the effect of a possible increase of the neutron fluence on the First Wall (FW) and of the use of tungsten instead of beryllium as inboard and outboard FW protective layer. The new analyses based on the recent ITER design have been performed using the

G. Cambi; D. G. Cepraga; L. Petrizzi; R. Villari; F. Moro

2009-01-01

423

Mapping and Analysing Local Tourism Systems in Italy, 1991–2001  

Microsoft Academic Search

The aim of this work is to identify and map tourist localities seen as concentrations of firms specialized in tourism services and to analyse their employment evolution over the last decade (1991–2001). The industrial districts approach is applied to the tourism industry by introducing the concept of the ‘tourist district’ in the literature relating to tourism research. In particular, the

Luciana Lazzeretti; Francesco Capone

2008-01-01

424

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

Microsoft Academic Search

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

Biringer

1987-01-01

425

Systematic analyses of vibration noise of a vibration isolation system for high-resolution scanning tunneling microscopes  

Microsoft Academic Search

We designed and constructed an effective vibration isolation system for stable scanning tunneling microscopy measurements using a separate foundation and two vibration isolation stages (i.e., a combination of passive and active vibration isolation dampers). Systematic analyses of vibration data along the horizontal and vertical directions are present, including the vibration transfer functions of each stage and the overall vibration isolation

Katsuya Iwaya; Ryota Shimizu; Tomihiro Hashizume; Taro Hitosugi

2011-01-01

426

Data Analyses and Simulation of the District of Columbia Trial Court System for the Processing of Felony Defendants.  

National Technical Information Service (NTIS)

The report, prepared by the Institute for Defense Analyses (IDA) at the request of the Department of Justice, deals with the problem of delay in the processing of felony defendants within the court system of the District of Columbia. The first of its two ...

J. G. Taylor J. A. Navarro R. H. Cohen

1968-01-01

427

SHAPS-2: A Three-Dimensional Computer Program for Linear/Non-Linear, Static/Dynamic Analyses of Piping Systems.  

National Technical Information Service (NTIS)

A three-dimensional computer program for linear/non-linear, static/dynamic analyses of reactor-piping systems under various accident loads is described. In the analysis, the hydrodynamic calculation can be performed in the implicit or semi-implicit manner...

C. Y. Wang

1985-01-01

428

DNA targets for the Escherichia coli K restriction system analysed genetically in recombinants between phages Phi80 and lambda  

Microsoft Academic Search

Genetic analyses demonstrate the segregation of three targets for the K restriction system in h80i? hybrid phages. Mutations in each of these three targets have been isolated and shown to confer resistance in cis but not in trans. Two of the three targets (sk-1 and sk-2) have been located on the ? genome: sk-1 is right of gene R and

Noreen E. Murray; Paola Manduca de Ritis; Lyndall A. Foster

1973-01-01

429

ANALYSES OF THE EFFECTS OF GLOBAL CHANGE ON HUMAN HEALTH AND WELFARE AND HUMAN SYSTEMS (SAP 4.6)  

EPA Science Inventory

EPA has released the draft document, Analyses of the Effects of Global Change on Human Health and Welfare and Human Systems for public review and comment. The notice has been posted by NOAA/ Department of Commerce on behalf of the U.S. Climate Change Science Program (CCS...

430

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...

431

Observations of working postures in garages using the Ovako Working Posture Analysing System (OVVAS) and consequent workload reduction recommendations  

Microsoft Academic Search

The working postures of mechanics (n = 84) in 42 garages were observed using the Ovako Working posture Analysis System (OWAS)During observation, both working postures and work activities were recorded. A computer program was developed for the data analyses. Using this program it is possible to calculate the working posture load for each work activity and the contribution of a

I. KANT; J. H. V. NOTERMANS; P. J. A. BORM

1990-01-01

432

Error Analyses and Modeling for CEBAF Beam Optical Systems: Beam Line Element Specifications and Alignment Error Tolerances  

SciTech Connect

A description of error analyses and computer modeling of the CEBAF transport system is given. The impact of various perturbations, including magnetic errors (mispowerings, misalignments, and inhomogeneities) and orbit correction, is discussed. Computations using analytical and numerical methods are presented, and error tolerance specifications described.

Douglas, David; Tang, Johnny

1991-05-01

433

Spectrum Transformation for Divergent Iterations.  

National Technical Information Service (NTIS)

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 t...

M. M. Gupta

1991-01-01

434

Iterative learning controller synthesis using FIR models for batch processes  

Microsoft Academic Search

Adaptive iterative learning control based on the measured input-output data is proposed to solve the traditional iterative\\u000a learning control problem in the batch process. It produces a control law with self-tuning capability by combining a batch-to-batch\\u000a model estimation procedure with the control design technique. To build the unknown batch operation system, the finite impulse\\u000a response (FIR) model with the lifted

Junghui Chen; Kuo-Tong Chou

2009-01-01

435

Evaluation of high-performance network technologies for ITER  

Microsoft Academic Search

For the fast feedback plasma controllers, ITER's Control, Data Access and Communication system (CODAC) will need to provide a mechanism for hard real-time communication between its distributed nodes.In particular, the ITER CODAC team identified four types of high-performance communication applications. Synchronous Databus Network (SDN) is to provide an ability to distribute parameters of plasma (estimated to about 5000 double-valued signals)

K. Zagar; S. Hunt; P. Kolaric; R. Sabjan; A. Zagar; J. Dedic

2010-01-01

436

Theoretical and Experimental Analyses of Photovoltaic Systems with Voltage and Current-Based Maximum Power Point Tracking  

Microsoft Academic Search

Detailed theoretical and experimental analyses are presented for the comparison of two simple fast and reliable maximum power point tracking (MPPT) techniques for photovoltaic systems (PV): the voltage-based (VMPPT) and the current-based (CMPPT) approaches. A microprocessor-controlled tracker capable of online voltage and current measurements and programmed with both VMPPT and CMPPT algorithms is constructed. The load of the solar system

M. A. Masoum; H. Dehbonei; E. F. Fuchs

2002-01-01

437

Theoretical and experimental analyses of photovoltaic systems with voltageand current-based maximum power-point tracking  

Microsoft Academic Search

Detailed theoretical and experimental analyses are presented for the comparison of two simple, fast and reliable maximum power-point tracking (MPPT) techniques for photovoltaic (PV) systems: the voltage-based (VMPPT) and the current-based (CMPPT) approaches. A microprocessor-controlled tracker capable of online voltage and current measurements and programmed with VMPPT and CMPPT algorithms is constructed. The load of the solar system is either

Mohammad A. S. Masoum; Hooman Dehbonei; Ewald F. Fuchs

2002-01-01

438

Automated Water Analyser Computer Supported System (AWACSS) Part I: Project objectives, basic technology, immunoassay development, software design and networking  

Microsoft Academic Search

A novel analytical system AWACSS (automated water analyser computer-supported system) based on immunochemical technology has been developed that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration nor pre-treatment steps.Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD) (98\\/83\\/EC,

Jens Tschmelak; Guenther Proll; Johannes Riedt; Joachim Kaiser; Peter Kraemmer; Luis Bárzaga; James S. Wilkinson; Ping Hua; J. Patrick Hole; Richard Nudd; Michael Jackson; Ram Abuknesha; Damià Barceló; Sara Rodriguez-Mozaz; Maria J. López de Alda; Frank Sacher; Jan Stien; Jaroslav Slobodník; Peter Oswald; Helena Kozmenko; Eva Korenková; Lívia Tóthová; Zoltan Krascsenits; Guenter Gauglitz

2005-01-01

439

Analyses of Variable Refrigerant Flow and Exergy in Air Conditioning Systems  

Microsoft Academic Search

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

Rashid Ali Alshatti

2011-01-01

440

Demonstration of ITER operational scenarios on DIII-D  

NASA Astrophysics Data System (ADS)

The DIII-D programme has recently initiated an effort to provide suitably scaled experimental evaluations of four primary ITER operational scenarios. New and unique features of this work are that the plasmas incorporate essential features of the ITER scenarios and anticipated operating characteristics; e.g. the plasma cross-section, aspect ratio and value of I/aB of the DIII-D discharges match the ITER design, with size reduced by a factor of 3.7. Key aspects of all four scenarios, such as target values for ?N and H98, have been replicated successfully on DIII-D, providing an improved and unified physics basis for transport and stability modelling, as well as for performance extrapolation to ITER. In all four scenarios, normalized performance equals or closely approaches that required to realize the physics and technology goals of ITER, and projections of the DIII-D discharges are consistent with ITER achieving its goals of >=400 MW of fusion power production and Q >= 10. These studies also address many of the key physics issues related to the ITER design, including the L-H transition power threshold, the size of edge localized modes, pedestal parameter scaling, the impact of tearing modes on confinement and disruptivity, beta limits and the required capabilities of the plasma control system. An example of direct influence on the ITER design from this work is a modification of the physics requirements for the poloidal field coil set at 15 MA, based on observations that the inductance in the baseline scenario case evolves to a value that lies outside the original ITER specification.

Doyle, E. J.; DeBoo, J. C.; Ferron, J. R.; Jackson, G. L.; Luce, T. C.; Murakami, M.; Osborne, T. H.; Park, J.-M.; Politzer, P. A.; Reimerdes, H.; Budny, R. V.; Casper, T. A.; Challis, C. D.; Groebner, R. J.; Holcomb, C. T.; Hyatt, A. W.; La Haye, R. J.; McKee, G. R.; Petrie, T. W.; Petty, C. C.; Rhodes, T. L.; Shafer, M. W.; Snyder, P. B.; Strait, E. J.; Wade, M. R.; Wang, G.; West, W. P.; Zeng, L.

2010-07-01

441

Demonstration of ITER Operational Scenarios on DIII-D  

SciTech Connect

The DIII-D program has recently initiated an effort to provide suitably scaled experimental evaluations of four primary ITER operational scenarios. New and unique features of this work are that the plasmas incorporate essential features of the ITER scenarios and anticipated operating characteristics; e.g., the plasma cross-section, aspect ratio and value of I/aB of the DIII-D discharges match the ITER design, with size reduced by a factor of 3.7. Key aspects of all four scenarios, such as target values for {beta}{sub N} and H{sub 98}, have been replicated successfully on DIII-D, providing an improved and unified physics basis for transport and stability modeling, as well as for performance extrapolation to ITER. In all four scenarios normalized performance equals or closely approaches that required to realize the physics and technology goals of ITER, and projections of the DIII-D discharges are consistent with ITER achieving its goals of {ge} 400 MW of fusion power production and Q {ge} 10. These studies also address many of the key physics issues related to the ITER design, including the L-H transition power threshold, the size of ELMs, pedestal parameter scaling, the impact of tearing modes on confinement and disruptivity, beta limits and the required capabilities of the plasma control system. An example of direct influence on the ITER design from this work is a modification of the specified operating range in internal inductance at 15 MA for the poloidal field coil set, based on observations that the measured inductance in the baseline scenario case lay outside the original ITER specification.

Doyle, E J; Budny, R V; DeBoo, J C; Ferron, J R; Jackson, G L; Luce, T C; Murakami, M; Osborne, T H; Park, J; Politzer, P A; Reimerdes, H; Casper, T A; Challis, C D; Groebner, R J; Holcomb, C T; Hyatt, A W; La Haye, R J; McKee, G R; Petrie, T W; Petty, C C; Rhodes, T L; Shafer, M W; Snyder, P B; Strait, E J; Wade, M R; Wang, G; West, W P; Zeng, L

2008-10-13

442

ITER on the road to fusion energy  

Microsoft Academic Search

On 21 November 2006, the government representatives of China, the European Union, India, Japan, Korea, Russia and the United States firmly committed to building the International Thermonuclear Experimental Reactor (ITER) [1] by signing the ITER Agreement. The ITER Organization, which was formally established on 24 October 2007 after ratification of the ITER Agreement in each Member country, is the outcome

Kaname Ikeda

2010-01-01

443

Linear iterative solvers for implicit ODE methods  

SciTech Connect

In this paper we consider the numerical solution of stiff initial value problems, which lead to the problem of solving large systems of mildly nonlinear equations. For many problems derived from engineering and science, a solution is possible only with methods derived from iterative linear equation solvers. A common approach to solving the nonlinear equations is to employ an approximate solution obtained from an explicit method. In this paper we shall examine the error to determine how it is distributed among the stiff and non-stiff components, which bears on the choice of an iterative method. Our conclusion is that error is (roughly) uniformly distributed, a fact that suggests the Chebyshev method (and the accompanying Manteuffel adaptive parameter algorithm). we describe this method, also commenting on Richardson's method and its advantages for large problems. We then apply Richardson's method and the Chebyshev method with the Manteuffel algorithm to the solution of the nonlinear equations by Newton's method. 25 refs.

Saylor, P.E.; Skeel, R.D.

1990-04-24

444

Cyclic Game Dynamics Driven by Iterated Reasoning  

PubMed Central

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.

Frey, Seth; Goldstone, Robert L.

2013-01-01

445

Possible design modifications of ITER fuel cycle  

SciTech Connect

During the ITER design phase, the conceptual design of the fuel processing cycle has been established. The fuel processing cycle is designed to be able to handle all the tritium containing streams of the ITER. These streams include plasma exhaust, blanket tritium recovery, pellet propellant, neutron beam exhaust, water coolant detritiation, waste water from the room air detritiation system. The design is very conservative, i.e., the flow rate of each stream is high and the detritiation factor required is very high. A preliminary optimization study has been carried out to simplify the ITER fuel cycle design. We investigated: The throughput and composition of the input tritium containing streams from various components to the fuel processing cycle. The fraction of those streams needed to be detritiated. The required detritiation factors required for each of the streams. The results of the investigation determined that the major input tritium containing steams can be reduced by at least a factor of 10. The required detritiation factor can be reduced from a factor of 100 to 10{sup 6}. The size of the fuel processing cycle, the tritium inventory and the complexity of this system can, therefore, also be reduced.

Sze, D.K.; Finn, P.A. (Argonne National Lab., IL (USA)); Anderson, J.; Bartlit, J.; Sherman, R. (Los Alamos National Lab., NM (USA))

1990-01-01

446

Design of the ITER Neutral Beam injectors  

SciTech Connect

This paper describes the Neutral Beam Injection system which is presently being designed in Europe, Japan and Russia, with co-ordination by the Joint Central Team of ITER at Naka, Japan. The proposed system consists of three negative ion based neutral injectors, delivering a total of 50 MW of 1 MeV D{sup 0} to the ITER plasma for pulse length of {ge}1000 s. The injectors each use a single caesiated volume arc discharge negative ion source, and a multi-grid, multi-aperture accelerator, to produce about 40 A of 1 MeV D{sup {minus}}. This will be neutralized in a sub-divided gas neutralizer, which has a conversion efficiency of about 60{percent}. The charged fraction of the beam emerging from the neutralizer is dumped in an electrostatic residual ion dump. A water cooled calorimeter can be moved into the beam path to intercept the neutral beam, allowing commissioning of the injector independent of ITER. {copyright} {ital 1996 American Institute of Physics.}

Hemsworth, R.S. [ITER Joint Central Team, ITER Naka Joint Work Site, 801-1 Mukouyama, Naka-machi, Naka-gun, Ibaraki-ken, 311-01 (Japan); Feist, J. [ITER European Home Team: IPP Garching, Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrae 2, D-85748 Garching b. Muenchen (Germany); Hanada, M. [ITER Joint Central Team, ITER Naka Joint Work Site 801-1 Mukouyama, Naka-machi, Naka-gun, Ibaraki-ken, 311-01 (Japan); Heinemann, B. [ITER European Home Team: IPP Garching, Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrae 2, D-85748 garching b. Muenchen (Germany); Inoue, T. [ITER Japanese Home Team: JAERI, Naka Fusion Research Establishment, 801-1 Mukouyama, Naka-machi, Naka-gun, 311-01 (Japan); Kuessel, E. [ITER European Home Team. KFA Juelich IPP, Postfach 1913, D-5170 Juelich (Germany); Kulygin, V.; Krylov, A. [ITER Russian Federation Home Team: RRC Kurchatov Institute, Institute of Nuclear Fusion, Ploshchad Akademika, Kurchatova 46, Moscow 123182 (Russia); Lotte, P. [ITER European Home Team: DRFC, CE Cadarache, 13108 St Paul Lez