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1

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

2

ECRH System For ITER  

NASA Astrophysics Data System (ADS)

A 26 MW Electron Cyclotron Heating and Current Drive (EC H&CD) system is to be installed for ITER. The main objectives are to provide, start-up assist, central H&CD and control of MHD activity. These are achieved by a combination of two types of launchers, one located in an equatorial port and the second type in four upper ports. The physics applications are partitioned between the two launchers, based on the deposition location and driven current profiles. The equatorial launcher (EL) will access from the plasma axis to mid radius with a relatively broad profile useful for central heating and current drive applications, while the upper launchers (ULs) will access roughly the outer half of the plasma radius with a very narrow peaked profile for the control of the Neoclassical Tearing Modes (NTM) and sawtooth oscillations. The EC power can be switched between launchers on a time scale as needed by the immediate physics requirements. A revision of all injection angles of all launchers is under consideration for increased EC physics capabilities while relaxing the engineering constraints of both the EL and ULs. A series of design reviews are being planned with the five parties (EU, IN, JA, RF, US) procuring the EC system, the EC community and ITER Organization (IO). The review meetings qualify the design and provide an environment for enhancing performances while reducing costs, simplifying interfaces, predicting technology upgrades and commercial availability. In parallel, the test programs for critical components are being supported by IO and performed by the Domestic Agencies (DAs) for minimizing risks. The wide participation of the DAs provides a broad representation from the EC community, with the aim of collecting all expertise in guiding the EC system optimization. Still a strong relationship between IO and the DA is essential for optimizing the design of the EC system and for the installation and commissioning of all ex-vessel components when several teams from several DAs will be involved together in the tests on the ITER site.

Darbos, C.; Henderson, M.; Albajar, F.; Bigelow, T.; Bomcelli, T.; Chavan, R.; Denisov, G.; Farina, D.; Gandini, F.; Heidinger, R.; Goodman, T.; Hogge, J. P.; Kajiwara, K.; Kasugai, A.; Kern, S.; Kobayashi, N.; Oda, Y.; Ramponi, G.; Rao, S. L.; Rasmussen, D.; Rzesnicki, T.; Saibene, G.; Sakamoto, K.; Sauter, O.; Scherer, T.; Strauss, D.; Takahashi, K.; Zohm, H.

2009-11-01

3

ECRH System For ITER  

SciTech Connect

A 26 MW Electron Cyclotron Heating and Current Drive (EC H and CD) system is to be installed for ITER. The main objectives are to provide, start-up assist, central H and CD and control of MHD activity. These are achieved by a combination of two types of launchers, one located in an equatorial port and the second type in four upper ports. The physics applications are partitioned between the two launchers, based on the deposition location and driven current profiles. The equatorial launcher (EL) will access from the plasma axis to mid radius with a relatively broad profile useful for central heating and current drive applications, while the upper launchers (ULs) will access roughly the outer half of the plasma radius with a very narrow peaked profile for the control of the Neoclassical Tearing Modes (NTM) and sawtooth oscillations. The EC power can be switched between launchers on a time scale as needed by the immediate physics requirements. A revision of all injection angles of all launchers is under consideration for increased EC physics capabilities while relaxing the engineering constraints of both the EL and ULs. A series of design reviews are being planned with the five parties (EU, IN, JA, RF, US) procuring the EC system, the EC community and ITER Organization (IO). The review meetings qualify the design and provide an environment for enhancing performances while reducing costs, simplifying interfaces, predicting technology upgrades and commercial availability. In parallel, the test programs for critical components are being supported by IO and performed by the Domestic Agencies (DAs) for minimizing risks. The wide participation of the DAs provides a broad representation from the EC community, with the aim of collecting all expertise in guiding the EC system optimization. Still a strong relationship between IO and the DA is essential for optimizing the design of the EC system and for the installation and commissioning of all ex-vessel components when several teams from several DAs will be involved together in the tests on the ITER site.

Darbos, C.; Henderson, M.; Gandini, F. [JTER Organization, 13067 Saint Paul-Lez-Durance cedex (France); Albajar, F.; Bomcelli, T.; Heidinger, R.; Saibene, G. [Fusion for Energy, C/Josep Pla 2, Torres Diagonal Litoral-B3, E-08019 Barcelona-Spain (Spain); Bigelow, T.; Rasmussen, D. [US ITER Project Office, Oak Ridge National Laboratory, 055 Commerce Park, PO Box 2008, Oak Ridge, TN 37831-6483 (United States); Chavan, R.; Goodman, T.; Hogge, J. P.; Sauter, O. [Association EURATOM-Confederation Suisse, EPFL Ecublens, CH-1015 Lausanne (Switzerland); Denisov, G. [Institute of Applied Physics Russian Academy of Sciences, 46 Ulyanov Street, Nizhny Novgorod, 603950 (Russian Federation); Farina, D. [Istitutodi Fisica del Plasma, Association EURATOM-ENEA-CNR, Milano (Italy); Kajiwara, K.; Kasugai, A.; Kobayashi, N.; Oda, Y.; Ramponi, G. [Japan Atomic Energy Agency (JAEA) 801-1 Mukoyama, Naka-shi, Ibaraki 311-0193 (Japan)] (and others)

2009-11-26

4

NON-AUTONOMOUS CONFORMAL ITERATED FUNCTION SYSTEMS  

E-print Network

NON-AUTONOMOUS CONFORMAL ITERATED FUNCTION SYSTEMS AND MORAN-SET CONSTRUCTIONS LASSE REMPE-GILLEN AND MARIUSZ URBA´NSKI Abstract. We study non-autonomous conformal iterated function systems, with finite or countable infinite alphabet alike. These differ from the usual (autonomous) iterated function systems

Urbanski, Mariusz

5

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

6

ANALYSES AND PRELIMINARY RESULTS OF AN UPDATED ITER RADIOACTIVE WASTE ASSESSMENT  

E-print Network

ANALYSES AND PRELIMINARY RESULTS OF AN UPDATED ITER RADIOACTIVE WASTE ASSESSMENT S. ZHENG,a * R aimed at updating the ITER radioactive inventory assessment and assisting the waste manage- ment operations, and waste management processes and services. KEYWORDS: ITER, radioactive waste management

7

Quadratic Newton Iteration for Systems with Multiplicity  

Microsoft Academic Search

.   \\u000a Newton's iterator is one of the most popular components of polynomial equation system solvers, either from the numeric or\\u000a symbolic point of view. This iterator usually handles smooth situations only (when the Jacobian matrix associated to the system\\u000a is invertible). This is often a restrictive factor. Generalizing Newton's iterator is still an open problem: How to design\\u000a an

Grégoire Lecerf; UMS MEDICIS

2002-01-01

8

Cryogenic system for ITER CS model coil  

SciTech Connect

A 5-kW/4.5-K helium refrigerator has been developed, which will be used for the test of ITER Central Solenoid Model Coil that is under fabrication by an international collaboration under the framework of the ITER Engineering Design Activity. Its acceptance test was recently finished and its specified refrigeration power of 5 kW with a surplus liquefaction rate of 114 1/h was demonstrated. A major feature of the refrigerator is that newly developed components, such as helium compressor and turbo-expander, are adopted in its simple refrigeration process in order that the results will be transferred to the ITER helium cryogenic system.

Kato, T.; Hamada, K.; Kawano, K.; Hiyama, T. [JAERI, Naka Fusion Research Establishment, Nada-machi, Nada-gun, Ibaraki-ken (Japan)] [and others

1996-12-31

9

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

10

Iterated maps for clarinet-like systems  

E-print Network

The dynamical equations of clarinet-like systems are known to be reducible to a non-linear iterated map within reasonable approximations. This leads to time oscillations that are represented by square signals, analogous to the Raman regime for string instruments. In this article, we study in more detail the properties of the corresponding non-linear iterations, with emphasis on the geometrical constructions that can be used to classify the various solutions (for instance with or without reed beating) as well as on the periodicity windows that occur within the chaotic region. In particular, we find a regime where period tripling occurs and examine the conditions for intermittency. We also show that, while the direct observation of the iteration function does not reveal much on the oscillation regime of the instrument, the graph of the high order iterates directly gives visible information on the oscillation regime (characterization of the number of period doubligs, chaotic behaviour, etc.).

Pierre-André Taillard; Jean Kergomard; Franck Laloë

2009-12-12

11

The ITER in-vessel system  

SciTech Connect

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.

1994-09-01

12

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

13

Process analyses of ITER Toroidal Field Structure cooling scheme  

NASA Astrophysics Data System (ADS)

Process studies for Toroidal Field Structure (TF ST) system with a dedicated Auxiliary Cold Box (ACB-ST) have been conducted under 15 MA baseline, including plasma disruptions. ACB-ST consists of two heat exchangers immersed in the Liquid Helium (LHe) subcooler, which are placed at the inlet/outlet of a Supercritical Helium (SHe) cold circulator (centrifugal pump). Robustness of ACB-ST is a key to achieve the stability of TF coil operation since it provides the thermal barrier at the interface of the TF Winding Pack (WP) with ST. The paper discusses the control logic for the nominal plasma operating scenario and for Mitigation to regulate the dynamic heat loads on ST. In addition, the operation field of a cold circulator is described in the case of plasma disruptions. The required performance of heat exchangers in the ACB-ST is assessed based on the expected operating conditions.

Maekawa, R.; Takami, S.; Iwamoto, A.; Chang, H. S.; Forgeas, A.; Chalifour, M.; Serio, L.

2014-09-01

14

A Recommendation System for Preconditioned Iterative Solvers  

E-print Network

December 2009 Major Subject: Computer Science A RECOMMENDATION SYSTEM FOR PRECONDITIONED ITERATIVE SOLVERS A Dissertation by THOMAS GEORGE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Vivek Sarin Committee Members, Patrick Lynett Valerie Taylor Yoonsuck Choe Head of Department, Valerie Taylor December 2009 Major Subject: Computer Science iii ABSTRACT A Recommendation...

George, Thomas

2011-02-22

15

Status of ITER RF systems design  

Microsoft Academic Search

ITER will require ?100 MW of auxiliary power for plasma heating, current drive and plasma kinetic control functions. As in most of the present-day tokamaks, these functions will be shared among different heating methods. A (negative-ion) neutral beam injection (NBI) and three RF heating and current drive (H&CD) systems - ion cyclotron (ICRF), electron cyclotron (ECRF) and lower hybrid (LBW)

G. Bosia; M. Makowski; G. Tonon

1998-01-01

16

Fuzzy logic components for iterative deconvolution systems  

NASA Astrophysics Data System (ADS)

Deconvolution systems rely heavily on expert knowledge and would benefit from approaches that capture this expert knowledge. Fuzzy logic is an approach that is used to capture expert knowledge rules and produce outputs that range in degree. This paper describes a fuzzy-deconvolution-system that integrates traditional Richardson-Lucy deconvolution with fuzzy components. The system is intended for restoration of 3D widefield images taken under conditions of refractive index mismatch. The system uses a fuzzy rule set for calculating sample refractive index, a fuzzy median filter for inter-iteration noise reduction, and a fuzzy rule set for stopping criteria.

Northan, Brian M.

2013-02-01

17

ITER relevant testing of a cryogenic distillation column system  

Microsoft Academic Search

A new experimental system has been constructed to test ITER relevant distillation columns and related cryogenic distillation (CD) hardware and control systems. These columns are used to purify tritium in the ITER fuel cycle. The ITER test column reported here has a diameter of about 30 mm and a packed length of approximately 150 cm. It can operate with a

D. G. Bellamy; J. R. Robins; K. B. Woodall; S. K. Sood; P. Gierszewski

1995-01-01

18

Iteration Stability for Simple Newtonian Stellar Systems  

E-print Network

For an equation of state in which pressure is a function only of density, the analysis of Newtonian stellar structure is simple in principle if the system is axisymmetric, or consists of a corotating binary. It is then required only to solve two equations: one stating that the "injection energy", $\\kappa$, a potential, is constant throughout the stellar fluid, and the other being the integral over the stellar fluid to give the gravitational potential. An iterative solution of these equations generally diverges if $\\kappa$ is held fixed, but converges with other choices. We investigate the mathematical reason for this convergence/divergence by starting the iteration from an approximation that is perturbatively different from the actual solution. A cycle of iteration is then treated as a linear "updating" operator, and the properties of the linear operator, especially its spectrum, determine the convergence properties. For simplicity, we confine ourselves to spherically symmetric models in which we analyze updating operators both in the finite dimensional space corresponding to a finite difference representation of the problem, and in the continuum, and we find that the fixed-$\\kappa$ operator is self-adjoint and generally has an eigenvalue greater than unity; in the particularly important case of a polytropic equation of state with index greater than unity, we prove that there must be such an eigenvalue. For fixed central density, on the other hand, we find that the updating operator has only a single eigenvector, with zero eigenvalue, and is nilpotent in finite dimension, thereby giving a convergent solution.

Richard H. Price; Charalampos Markakis; John L. Friedman

2009-03-18

19

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

20

Gas species, their evolution and segregation through the ITER vacuum systems  

SciTech Connect

This paper takes the ITER fueling requirements and current knowledge of gas balance and exhaust from operating tokamaks to predict all likely gas inputs into the ITER Vacuum systems. Areas where gas dynamics modeling is relevant to the ITER design are highlighted. The design and operation of the ITER vacuum system gives an element of segregation of different gas flows and species. This paper analyses the time dependent gas segregation in the vacuum system resulting from different temperature dependences of cryogenic sorption and condensation processes of different gas species. As a specific example, the optimal transfer of Ar-41 through the vacuum system is studied with respect to its decay and the resulting effects on the design of system components.

Pearce, R.J.H. [ITER Organization, Cadarache, France; Antipenkov, Alexander [ITER Joint Work Site, Cadarache; Bersier, Jean-Louis [ITER Joint Work Site, Cadarache; Boussier, Bastien [ITER Joint Work Site, Cadarache; Baylor, Larry R [ORNL; Gardner, Walter L [ORNL; Meitner, Steven J [ORNL

2012-01-01

21

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

22

Iterative Common Phase Error Correction in OFDM Systems  

Microsoft Academic Search

This paper deals with iterative common phase error correction in an OFDM system. Common phase error is the average phase shift of the sub carriers due to mismatch between the transmitter and receiver oscillator phases. It causes substantial degradation in receiver performance and should be compensated. In this paper an iterative scheme is proposed which feedbacks the symbol estimates available

Asma Bibi; Aizaz Ali Shah; Shahid Khattak

2011-01-01

23

Thermo-mechanical analyses of ITER in-vessel magnetic sensor assembly  

NASA Astrophysics Data System (ADS)

This paper summarizes the work concerning design studies of the ITER in-vessel discrete magnetic sensor assemblies, with particular emphasis on the thermal behaviour of the Low Temperature Co-fired Ceramic (LTCC) magnetic sensor and on the thermo-mechanical aspects of the interface with the Vacuum Vessel (VV). The paper summarises the results of FEM thermal analyses performed on the LTCC sensor head and on the sensor assembly to assess the temperature distribution during operating conditions, which could affect the sensor signal due to Temperature-Induced Electromotive Force effect. The paper then concentrates on mechanical analysis of the Base-Plate to assess that the stress and deformation due to the welding to the VV are acceptable to guarantee a sound installation and a suitable thermal contact of the sensor assembly to the VV.

Gonzalez, W.; Arshad, S.; Peruzzo, S.; Portales, M.; Rizzolo, A.; Vayakis, G.

2014-08-01

24

Gas Analyses of First complete JET Cryopump Regeneration with ITER-Like Wall  

E-print Network

Analytical results of a complete JET cryopump regeneration, including the nitrogen panel, following the first ITER-Like Wall campaign are presented along with the in-situ analyses of residual gas. H/D mixtures and impurities such as nitrogen and neon were injected during plasma operation in the vessel to study radiation cooling in the scrape-off-layer and divertor region. The global gas inventory over the campaign is incomplete, suggesting residual volatile impurities are remaining on the cryogenic panel. This paper presents results on a) residual deuterium on the panel which is related to the campaign very low, b) impurities like nitrogen which sticks on the panel and c) the ammonia production which can be observed in the RGA spectrum.

Romanelli, S Grunhagen; Butler, B; Coad, J P; Drenik, A; Giroud, C; Jachmich, S; Keenan, T; Kruezi, U; Mozetic, M; Oberkofler, M; Parracho, A; Romanelli, M; Smith, R; contributors, JET EFDA

2014-01-01

25

iterative solution of augmented systems arising in interior methods  

E-print Network

of Technology, Stockholm; Department of Mathematics, University of California, .... During the early outer iterations, it is usually inefficient to solve the KKT system ... in the null space of A. A disadvantage with this approach is that the constraint.

2005-09-04

26

Performance and capacity analysis of Poisson photon-counting based Iter-PIC OCDMA systems.  

PubMed

In this paper, an iterative parallel interference cancellation (Iter-PIC) technique is developed for optical code-division multiple-access (OCDMA) systems relying on shot-noise limited Poisson photon-counting reception. The novel semi-analytical tool of extrinsic information transfer (EXIT) charts is used for analysing both the bit error rate (BER) performance as well as the channel capacity of these systems and the results are verified by Monte Carlo simulations. The proposed Iter-PIC OCDMA system is capable of achieving two orders of magnitude BER improvements and a 0.1 nats of capacity improvement over the conventional chip-level OCDMA systems at a coding rate of 1/10. PMID:24216821

Li, Lingbin; Zhou, Xiaolin; Zhang, Rong; Zhang, Dingchen; Hanzo, Lajos

2013-11-01

27

Iterative learning control for dual stroke actuator systems  

NASA Astrophysics Data System (ADS)

This paper presents a dual iterative learning control strategy for a dual stroke actuator system in the lithography scanner. The motion control strategy is employed, in which the trajectory of a short stroke stage is followed by one of a long stroke stage. A short stroke stage is used for improving the system response performance while a long stroke stage is introduced for the purpose of long motion stroke of the system. Combining the dynamic model of the system, the coupling effects between two actuators are analyzed, and the system model is simplified. This model is used for the design of a dual iterative learning control strategy and decoupling controllers. As a result, the heavy proportion of the recurrent coupling force on the long stroke stage is eliminated by the decoupling feedforward action from the output of the short stroke stage in the scanning process. The rest of the coupling force is removed by the first iterative learning control between two subsystems. The impact on the short stroke stage from the long stroke stage is weakened, and the short stroke stage is then designed independently by the two degree of freedom control strategy combining feedback control with the second iterative learning control. The convergence of the iterative learning control system is shown, and the effectiveness of the combined method is verified by a simulated wafer stage.

Jiang, Xiaoming; Wang, Yan; Li, Xin; Liu, Yang; Chen, Xinglin

2013-01-01

28

ITER fuelling, pumping, wall conditioning systems and fuel dynamics analysis  

Microsoft Academic Search

In this paper, the status of the ITER fuelling, pumping and wall conditioning systems design and the results of fuel dynamics analysis will be presented. The fuelling system consists of both gas and pellet injection. The max. DT gas fuelling rate is 500 Pa m3 s?1 during a plasma density rise and 200 Pa m3 s?1 during steady state DT

H. Nakamura; P. Ladd; G. Federici; G. Janeschitz; K. M. Schaubel; M. Sugihara; A. Busigin; P. J. Gierszewski; S. Hiroki; H. S. Hurzlmeier; W. Kuan; R. A. Marrs; R. R. Parker; D. Post

1998-01-01

29

MIMO Systems: Principles, iterative techniques and advanced polarization  

E-print Network

. . . . . . . . . . . . . . . . . . . . . . . 7 1.3.2 MIMO Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.3.3 Some next study the "MIMO channel capacity" and present the early developments in these systems, concerningMIMO Systems: Principles, iterative techniques and advanced polarization K. Raoof 1 , M.A. Khalighi

Paris-Sud XI, Université de

30

Variational iteration method for autonomous ordinary differential systems  

Microsoft Academic Search

In this paper, a new iteration technique is proposed to solve autonomous ordinary differential systems. In this method, general Lagrange multipliers are introduced to construct correction functionals for the systems. The multipliers in the functionals can be identified by the variational theory. The initial approximations can be freely chosen with possible unknown constants, which can be determined by imposing the

Ji-Huan He

2000-01-01

31

Tritium module for ITER/Tiber system code  

SciTech Connect

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

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

1988-01-01

32

Tritium module for ITER/TIBER system code  

SciTech Connect

A tritium module was developed for the ITER/TIBER system code to provide information on capital costs, tritium inventory, power requirements, and building volumes for these systems. In the tritium module, the main tritium subsystems - plasma processing, atmospheric cleanup, water cleanup, blanket processing - are each represented.

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

1988-09-01

33

Polygon-based fractals from compressed iterated function systems.  

PubMed

This paper addresses the equivalence between iterative function systems (IFS). It also explains how to classify and reduce the parameter space for a particular class of IFS.The proposed method generates various fractal textures for regular polygons and allows the creation of polygon-based fractal flakes, polygon-based spirals, and many other forms. It employs sth-order restriction, a new version of recurrent iterated function systems. Level-specified symmetry in the fractals is controlled through rth-level symmetrization. PMID:20650709

Van Loocke, Philip

2010-01-01

34

ITER diagnostic systems in development in Ioffe Institute  

NASA Astrophysics Data System (ADS)

Three diagnostic systems are being developed in Ioffe Institute for ITER. Those are Neutral Particle Analysis (NPA), Thomson Scattering in Divertor (TSD) and Gamma Spectroscopy (GS). The main objective of NPA in ITER is to measure D/T fuel ration in plasma on the basis of measurement of neutralized fluxes of D and T ions [1]. Fuel ratio is one of the key parameters needed by ITER control system to provide the optimal conditions in plasma and the most effective plasma burning. Another objective is to measure the distribution function of fast ions (including alpha particles) generated as a result of the additional heating and nuclear fusion reactions. Thomson Scattering in Divertor (TSD) [2] will be used to measure electron temperature and density in the scrape-off layer in outer leg of ITER divertor. The main task of TSD is to protect the machine from divertor overloading. Gamma Spectroscopy (GS) [3] is based on the measurement of spectral lines of MeV range gammas generated in nuclear reactions in plasma. 2-D gamma-ray emission measurements give valuable information on the confined alpha particles in DT plasma. They also provide important information on the location of MeV range runaway electron beams in ITER plasma. For all three cases the physical basis and instrumentation are presented. The simple NPA version for measurements of D/T ratio in DEMO is also briefly described.

Petrov, M.; Afanasyev, V.; Petrov, S.; Mironov, M.; Mukhin, E.; Tolstyakov, S.; Chugunov, I.; Shevelev, A.

2014-08-01

35

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

36

NITSOL: A Newton iterative solver for nonlinear systems  

SciTech Connect

Newton iterative methods, also known as truncated Newton methods, are implementations of Newton`s method in which the linear systems that characterize Newton steps are solved approximately using iterative linear algebra methods. Here, we outline a well-developed Newton iterative algorithm together with a Fortran implementation called NITSOL. The basic algorithm is an inexact Newton method globalized by backtracking, in which each initial trial step is determined by applying an iterative linear solver until an inexact Newton criterion is satisfied. In the implementation, the user can specify inexact Newton criteria in several ways and select an iterative linear solver from among several popular {open_quotes}transpose-free{close_quotes} Krylov subspace methods. Jacobian-vector products used by the Krylov solver can be either evaluated analytically with a user-supplied routine or approximated using finite differences of function values. A flexible interface permits a wide variety of preconditioning strategies and allows the user to define a preconditioner and optionally update it periodically. We give details of these and other features and demonstrate the performance of the implementation on a representative set of test problems.

Pernice, M. [Univ. of Utah, Salt Lake City, UT (United States); Walker, H.F. [Utah State Univ., Logan, UT (United States)

1996-12-31

37

The Iterating Artifact as a Fundamental Construct in Information System Design  

Microsoft Academic Search

Iterative development is fundamental principle of information system design methodologies. Yet, the idea of iteration remains poorly defined across literature streams. In this essay we identify the types of iterations that can occur in software development processes, and organize them into typologies by the iterating artifacts they generate. We then see how a sample of development approaches discuss these artifacts

Nicholas Berente; Kalle Lyytinen

38

Low complexity iterative receiver for linear precoded MIMO systems  

E-print Network

Low complexity iterative receiver for linear precoded MIMO systems Pierre-Jean Bouvet, Maryline Email: pierrejean.bouvet@rd.francetelecom.com Abstract-- In a Multiple Input Multiple Output (MIMO of the space-time detector which consists of an MMSE MIMO PSIC equalizer and a linear deprecoder. Spectral

Paris-Sud XI, Université de

39

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 fl ow rate to ensure target thickness

KRYLOV Alexander; INOUE Takashi

2005-01-01

40

Iterated belief change in multi-agent systems  

Microsoft Academic Search

We give a model for iterated belief change in multi-agent systems. The formal tool we use for this is a combination of modal and dynamic logic. Two core notions in our model are the expansion of the knowledge and beliefs of an agent, and the processing of new information. An expansion has been defined as the change in the knowledge

Jan-Willem Roorda; Wiebe van der Hoek; John-Jules Ch. Meyer

2002-01-01

41

Iterative learning control for the liquid rocket propulsion systems  

NASA Astrophysics Data System (ADS)

This paper addressed mathematical modeling and control of liquid rocket propulsion system (LRPS). Dynamic simulation of LRPS shows that control difficulty is rooted from the slow dynamics and high nonlinearity of the rocket motion. As a consequence a conventional feedback control technique is unsuitable for controlling the rocket motion. In this paper, it is proposed to use both cascade and iterative learning control techniques including feedback controllers. Using the cascade control algorithm it is enabled to overcome the control difficulty to a certain degree caused by the variation of time constants. Iterative learning control strategies improve the tracking performance and guarantee the safety through repetition. The LRPS control system which tracks the changes in the set-point and also diminishes the disturbance under modeling error has been synthesized. Overall performance of proposed control system has been demonstrated by means of thorough numerical simulation of LRPS control system.

Ryu, Youngsu; Lee, Tai-yong; Jung, Youngsuk; Oh, Seunghyub

2005-12-01

42

Critical interface issues associated with the ITER EC system  

NASA Astrophysics Data System (ADS)

The ITER ECH system is an in-kind procurement consisting of four different types of gyrotrons (from EU, IN, JA and RF), transmission lines (from US) and two types of launchers (from EU and JA). Each subsystem must interface not only with the other but also with the auxiliary systems control and data acquisition computer and with the plasma (in the case of the launchers). The definition and management of interfaces is therefore essential for the system to guarantee performance, availability and reliability. The proper description of each interface boundary is essential for assembly and operation of the entire system as a single unit. In addition, progress has been made in the development of high power, long pulse systems and associated components that have not been integrated into the ITER EC design since the present ITER EC system was essentially specified prior to 2000. The ultimate physics performance and operational reliability in some situations is limited by this old design, which has not taken advantage of the knowledge and experience gained in operating the multi-megawatt ECH systems on present tokamaks and stellarators. The objective of this paper is to review the present ITER ECH system, which includes the power supplies, gyrotrons, transmission lines and launchers. Modifications are proposed which are performance driven and are engineered for reliability and maintainability, whilst reducing complexity and cost. Potential operating scenarios are discussed which require an intelligent and automatic decision making process, for example, directing the EC power to either of the two EC launchers, based on the immediate physics requirements. The interfaces between the subsystems are described and when possible improvements to each interface are proposed.

Henderson, M. A.; Saibene, G.

2008-05-01

43

Defining the infrared systems for ITER  

SciTech Connect

The International Thermonuclear Experimental Reactor will have wide angle viewing systems and a divertor thermography diagnostic, which shall provide infrared coverage of the divertor and large parts of the first wall surfaces with spatial and temporal resolution adequate for operational purposes and higher resolved details of the divertor and other areas for physics investigations. We propose specifications for each system such that they jointly respond to the requirements. Risk analysis driven priorities for future work concern mirror degradation, interfaces with other diagnostics, radiation damage to refractive optics, reflections, and the development of calibration and measurement methods for varying optical and thermal target properties.

Reichle, R.; Andrew, P.; Drevon, J.-M.; Encheva, A.; Janeschitz, G.; Levesy, B.; Martin, A.; Pitcher, C. S.; Pitts, R.; Thomas, D.; Vayakis, G.; Walsh, M. [ITER Organization, 13115 St. Paul-lez-Durance (France); Counsell, G. [F4E, Torres Diagonal Litoral B3, 08091 Barcelona (Spain); Johnson, D. [Princeton Plasma Physics Laboratory, Princeton, New Jersey (United States); Kusama, Y. [JAEA, Naka-shi, Ibaraki 311-0193 (Japan)

2010-10-15

44

Defining the infrared systems for ITER.  

PubMed

The International Thermonuclear Experimental Reactor will have wide angle viewing systems and a divertor thermography diagnostic, which shall provide infrared coverage of the divertor and large parts of the first wall surfaces with spatial and temporal resolution adequate for operational purposes and higher resolved details of the divertor and other areas for physics investigations. We propose specifications for each system such that they jointly respond to the requirements. Risk analysis driven priorities for future work concern mirror degradation, interfaces with other diagnostics, radiation damage to refractive optics, reflections, and the development of calibration and measurement methods for varying optical and thermal target properties. PMID:21033997

Reichle, R; Andrew, P; Counsell, G; Drevon, J-M; Encheva, A; Janeschitz, G; Johnson, D; Kusama, Y; Levesy, B; Martin, A; Pitcher, C S; Pitts, R; Thomas, D; Vayakis, G; Walsh, M

2010-10-01

45

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...

46

Annual Report of the EURATOM/UKAEA Fusion Programme 2008/09 8 ITER Systems  

E-print Network

Annual Report of the EURATOM/UKAEA Fusion Programme 2008/09 8.1 8 ITER Systems 8 ITER Systems 8.1 OVERVIEW For ITER to achieve its goals it needs high performance heating and current drive systems to drive the responsibility of the new `Fusion for Energy' agency (F4E) in Barcelona. Our participation is mainly via F4E

47

ITERATIVE SUBSTRUCTURING METHODS FOR SPECTRAL ELEMENT DISCRETIZATIONS OF ELLIPTIC SYSTEMS.  

E-print Network

. linear elasticity, spectral element methods, preconditioned iterative methods, substruc­ turing, Gauss of efficient iterative methods. Solvers which combine a Krylov space accelerator with a robust preconditioner

Widlund, Olof B.

48

Iterated Belief Change in Multi-Agent Systems  

Microsoft Academic Search

Abstract We give a model for iterated belief change in multi-agent systems. The formal tool we use for this is a combination of modal,and dynamic,logic. Two core notions in our model are the expansion of the knowledge and beliefs of an agent ,a ndthe processing of new information. An expansion is dened,as the change in the knowledge,and beliefs of an

Jan-willem Roorda; Wiebe Van Der Hoek; John-jules Ch. Meyer

2003-01-01

49

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

50

Newton iterative methods for large scale nonlinear systems  

SciTech Connect

Objective is to develop robust, efficient Newton iterative methods for general large scale problems well suited for discretizations of partial differential equations, integral equations, and other continuous problems. A concomitant objective is to develop improved iterative linear algebra methods. We first outline research on Newton iterative methods and then review work on iterative linear algebra methods. (DLC)

Walker, H.F.; Turner, K.

1993-01-01

51

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

52

Aviation forecasting and systems analyses  

SciTech Connect

The 9 papers in this report deal with the following areas: method of allocating airport runway slots; method for forecasting general aviation activity; air traffic control network-planning model based on second-order Markov chains; analyzing ticket-choice decisions of air travelers; assessing the safety and risk of air traffic control systems: risk estimation from rare events; forecasts of aviation fuel consumption in Virginia; estimating the market share of international air carriers; forecasts of passenger and air-cargo activity at Logan International Airport; and forecasting method for general aviation aircraft and their activity.

Geisinger, K.E.; Brander, J.R.G.; Wilson, F.R.; Kohn, H.M.; Polhemus, N.W.

1980-01-01

53

Physics Requirements for the ITER Plasma Control System  

NASA Astrophysics Data System (ADS)

The Plasma Control System (PCS) on ITER will control the evolution of the plasma parameters necessary to operate ITER throughout all phases of the discharge including plasma termination following off-normal events and plant system faults. The PCS is composed of six closely coupled subsystems that control specific physical quantities comprising: 1) wall conditioning and tritium removal, 2) plasma axisymmetric magnetic control, which includes plasma initiation, inductive plasma current, position, and shape control, 3) power and particle flux control to the first wall and divertor, 4) plasma kinetic control, including fuelling, non-inductive plasma current, plasma pressure and fusion burn control, 5) non-axisymmetric stability control, which includes sawteeth, edge localized modes (ELMs), neoclassical tearing modes (NTMs), error fields and resistive wall modes (RWMs), Alfven eigenmodes, etc., and 6) disruption mitigation and controlled plasma termination. The PCS is the first of a three layered system for machine protection that will decide the course of action to take following off-normal events or plant system faults during plasma operation together with the Central Interlock System (CIS) and the Central Safety System (CSS) for safety related events. Only if the PCS cannot control the plasma within specified operating limits and conditions will the disruption mitigation system by triggered by the CIS.

Snipes, J. A.; Gribov, Y.; Winter, A.

2009-11-01

54

NITSOL: A Newton iterative solver for nonlinear systems  

SciTech Connect

The authors introduce a well-developed Newton iterative (truncated Newton) algorithm for solving large-scale nonlinear systems. The framework is an inexact Newton method globalized by backtracking. Trial steps are obtained using one of several Krylov subspace methods. The algorithm is implemented in a Fortran solver called NITSOL that is robust yet easy to use and provides a number of useful options and features. The structure offers the user great flexibility in addressing problem specificity through preconditioning and other means and allows easy adaptation to parallel environments. Features and capabilities are illustrated in numerical experiments.

Pernice, M. [Univ. of Utah, Salt Lake City, UT (United States). Center for High Performance Computing] [Univ. of Utah, Salt Lake City, UT (United States). Center for High Performance Computing; Walker, H.F. [Utah State Univ., Logan, UT (United States). Dept. of Mathematics and Statistics] [Utah State Univ., Logan, UT (United States). Dept. of Mathematics and Statistics

1998-01-01

55

SCENARIO ANALYSES OF CALIFORNIA'S ELECTRICITY SYSTEM: PRELIMINARY  

E-print Network

CALIFORNIA ENERGY COMMISSION SCENARIO ANALYSES OF CALIFORNIA'S ELECTRICITY SYSTEM: PRELIMINARY Bender Acting Deputy Director ELECTRICITY SUPPLY ANALYSIS DIVISION B. B. Blevins Executive Director CHAPTER 2: Retirement and Replacement of Aging Power Plants in California

56

Initial results of systems analysis ETR/ITER 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. They 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}> 1.0 MW/m{sup 2}) leads to minimum size at higher A ({approx} 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 asumptions 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.

Peng, Yueng Kay Martin [ORNL] [ORNL; Galambos, John D [ORNL] [ORNL; Reid, R. L. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Strickler, Dennis J [ORNL] [ORNL

1987-01-01

57

Convergence Acceleration of Iterative Signal Detection for MIMO System with Belief Propagation  

NASA Astrophysics Data System (ADS)

In multiple-input multiple-output (MIMO) wireless systems, the receiver must extract each transmitted signal from received signals. Iterative signal detection with belief propagation (BP) can improve the error rate performance, by increasing the number of detection and decoding iterations in MIMO systems. This number of iterations is, however, limited in actual systems because each additional iteration increases latency, receiver size, and so on. This paper proposes a convergence acceleration technique that can achieve better error rate performance with fewer iterations than the conventional iterative signal detection. Since the Log-Likelihood Ratio (LLR) of one bit propagates to all other bits with BP, improving some LLRs improves overall decoder performance. In our proposal, all the coded bits are divided into groups and only one group is detected in each iterative signal detection whereas in the conventional approach, each iterative signal detection run processes all coded bits, simultaneously. Our proposal increases the frequency of initial LLR update by increasing the number of iterative signal detections and decreasing the number of coded bits that the receiver detects in one iterative signal detection. Computer simulations show that our proposal achieves better error rate performance with fewer detection and decoding iterations than the conventional approach.

Gounai, Satoshi; Ohtsuki, Tomoaki

58

Iterative development of visual control systems in a research vivarium.  

PubMed

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

Bassuk, James A; Washington, Ida M

2014-01-01

59

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

NASA Astrophysics Data System (ADS)

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 for neutralisation. Optimizing the beam transmission and reionisation loss of neutral beams, the axial length of the ITER NB injector was shortened to be 23.4 m with a reasonably high injection ef ciency. Three-dimensional neutron transport analyses clari ed possible excess power dissipation due to radiation-induced conductivity, if the high voltage is insulated by conventional gas such as SF6. Thus, design of vacuum insulated beam source has been established for the present ITER NB system.

Krylov, Alexander; Inoue, Takashi

60

Simplified thermal model of the ITER magnet system  

NASA Astrophysics Data System (ADS)

A simplified thermal model of the ITER magnet system has been developed to capture the essence of the magnet heat load dynamics without the need for extensive computations. Idealization of the magnets has been made using mainly two standard types of elements, solids and tubes. No Navier-Stokes equations have been solved for the hydraulics, but instead a simple transport model with approximation for pressure evolution has been used. The model was implemented in C language and used to investigate the important features needed to implement a computationally efficient and fast magnet thermal model capturing overall behavior in terms of superconductor cooling channel description (thermal coupling with jackets, presence of the conductor, importance of the central channel, etc.). Furthermore, the model was benchmarked against validated simulation tools such as SuperMagnet and Vincenta using the ITER Central Solenoid normal operation scenario for comparison. Dynamics were shown to be reproduced in good agreement with results attainable with these more detailed codes, considering the high level of uncertainty on the input parameters, namely the heat transfer coefficients and the values of heat loads.

Furci, Hernán; Luongo, Cesar

2014-09-01

61

Chevron beam dump for ITER edge Thomson scattering system  

SciTech Connect

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.

Yatsuka, E.; Hatae, T.; Bassan, M.; Itami, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Vayakis, G. [ITER Organization, 13115 St Paul Lez Durance Cedex (France)] [ITER Organization, 13115 St Paul Lez Durance Cedex (France)

2013-10-15

62

Chevron beam dump for ITER edge Thomson scattering system  

NASA Astrophysics Data System (ADS)

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.

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

2013-10-01

63

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

64

Efficient and reliable iterative methods for linear systems  

NASA Astrophysics Data System (ADS)

The approximate solutions in standard iteration methods for linear systems Ax=b, with A an n by n nonsingular matrix, form a subspace. In this subspace, one may try to construct better approximations for the solution x. This is the idea behind Krylov subspace methods. It has led to very powerful and efficient methods such as conjugate gradients, GMRES, and Bi-CGSTAB. We will give an overview of these methods and we will discuss some relevant properties from the user's perspective view. The convergence of Krylov subspace methods depends strongly on the eigenvalue distribution of A, and on the angles between eigenvectors of A. Preconditioning is a popular technique to obtain a better behaved linear system. We will briefly discuss some modern developments in preconditioning, in particular parallel preconditioners will be highlighted: reordering techniques for incomplete decompositions, domain decomposition approaches, and sparsified Schur complements.

van der Vorst, Henk A.

2002-12-01

65

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

66

Analysing Performance of Lift Systems in PEPA  

E-print Network

to quite complex multi­lift systems, with a high degree of parallelism and non­determinism present (eAnalysing Performance of Lift Systems in PEPA Amani El­Rayes and Marta Kwiatkowska and Steven Minton \\Lambda Abstract We use the stochastic process algebra PEPA [8] to specify lift sys­ tems

Oxford, University of

67

Iterative Prony Method Based Power System Low Frequency Oscillation Mode Analysis and PSS Design  

Microsoft Academic Search

This paper presents an identification method based on the iterative Prony to identify transfer function and configure PSS parameters using residue way. The iterative Prony is a very useful method to acquire power system oscillation modes, by which the system eigenvalue, oscillation frequency, amplitude, damping and relative phase can be directly estimated using the response of given input signals. Considering

Hu Guoqiang; He Renmu; Yang Huachun; Wang Peng; Ma Rui

2005-01-01

68

A Modified Iterative Water-filling Algorithm with Per-iteration Power Normalization in Multiuser MMSE-Precoded MIMO Systems  

Microsoft Academic Search

In this paper, we deal with an optimum per-user power allocation problem in terms of the sum capacity in multiuser multiple input multiple output (MU-MIMO) downlink systems when the minimum mean square error (MMSE) scheme has been used for multiuser preceding. However, MMSE preceding allows some inter-user interference. In this paper, we propose a modified iterative water-filling (MIWF) algorithm with

Min Lee; Seong Keun Oh

2008-01-01

69

Physics analysis of the ITER ECW system for optimized performance  

NASA Astrophysics Data System (ADS)

A predictive analysis of the capabilities of the ITER electron cyclotron wave system is presented in this work. Modifications of both the upper launcher and the equatorial launcher aimed at increasing the potentialities of the system are identified and discussed. A modification of the upper launcher has already been incorporated in the updated front steering design called the extended physics launcher. By adopting different deposition ranges for the upper and lower steering mirrors, this design offers the flexibility to drive current from the radial region required for the stabilization of neoclassical tearing modes (NTM) up to that required for sawtooth control, allowing a synergy with the equatorial launcher. Here a comparison of the performance of the new design of the upper launcher with those of a dropped upper launcher is performed, showing that better performance for both NTM stabilization and sawtooth control may be obtained by lowering the upper port location. An analysis of the EC current driven by the equatorial launcher is also presented, showing that adding to the present design the possibility to drive counter-current in addition to the existing co-current capability would increase the flexibility of the system. The behaviour of all launchers at reduced magnetic fields is also discussed.

Ramponi, G.; Farina, D.; Henderson, M. A.; Poli, E.; Sauter, O.; Saibene, G.; Zohm, H.; Zucca, C.

2008-05-01

70

Decentralized iterative learning control for a class of large scale interconnected dynamical systems  

NASA Astrophysics Data System (ADS)

The problem of decentralized iterative learning control for a class of large scale interconnected dynamical systems is considered. In this paper, it is assumed that the considered large scale dynamical systems are linear time-varying, and the interconnections between each subsystem are unknown. For such a class of uncertain large scale interconnected dynamical systems, a method is presented whereby a class of decentralized local iterative learning control schemes is constructed. It is also shown that under some given conditions, the constructed decentralized local iterative learning controllers can guarantee the asymptotic convergence of the local output error between the given desired local output and the actual local output of each subsystem through the iterative learning process. Finally, as a numerical example, the system coupled by two inverted pendulums is given to illustrate the application of the proposed decentralized iterative learning control schemes.

Wu, Hansheng

2007-03-01

71

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

72

An Overview Of The ITER In-Vessel Coil Systems  

SciTech Connect

ELM mitigation is of particular importance in ITER in order to prevent rapid erosion or melting of the divertor surface, with the consequent risk of water leaks, increased plasma impurity content and disruptivity. Exploitable "natural" small or no ELM regimes might yet be found which extrapolate to ITER but this cannot be depended upon. Resonant Magnetic Perturbation has been added to pellet pacing as a tool for ITER to mitigate ELMs. Both are required, since neither method is fully developed and much work remains to be done. In addition, in-vessel coils enable vertical stabilization and RWM control. For these reasons, in-vessel coils (IVCs) are being designed for ITER to provide control of Edge Localized Modes (ELMs) in addition to providing control of moderately unstable resistive wall modes (RWMs) and the vertical stability (VS) of the plasma.

Heitzenroeder, P J; Chrzanowski, J H; Dahlgren, F; Hawryluk, R J; Loesser, G D; Neumeyer, C; Mansfield, C; Smith, J P; Schaffer, M; Humphreys, D; Cordier, J J; Campbell, D; Johnson, G A; Martin, A; Rebut, P H; Tao, J O; Fogarty, P J; Nelson, B E

2009-09-24

73

Design of Iterative Learning Controllers for Linear Discrete Systems with Multiple Time Delays  

NASA Astrophysics Data System (ADS)

The problem of iterative learning control is considered for a class of linear discrete systems with multiple time delays. In this paper, it is assumed that the initial condition for discrete time-delay systems is unknown at each iteration. For such a class of discrete time-delay systems, a method is presented whereby a class of discrete iterative learning control schemes can be constructed. It is shown that under some given conditions, the constructed iterative learning controllers can guarantee the asymptotic convergence of the output error between the given desired output and the actual output through the iterative learning process. Finally, a numerical example is given to demonstrate the validity of the results.

Wu, Hansheng

74

Design of Decentralized Iterative Learning Controllers for Linear Large Scale Dynamical Systems  

NASA Astrophysics Data System (ADS)

The problem of decentralized iterative learning control is considered for a class of linear time-invariant large scale interconnected dynamical systems. In the paper, it is shown that the method of iterative learning control can be applied to such large scale interconnected dynamical systems, and a class of decentralized local iterative learning control schemes is proposed. It is aslo shown that under given conditions, the proposed decentralized local iterative learning controllers can guarantee the asymptotic convergence of the local output error between the given desired local output and the actual local output of each subsystem through the iterative learning process. Finally, a numerical example is given to demonstrate the validity of the results.

Wu, Hansheng

75

Symbol Synchronization in Coded UWB Systems using Adaptive Iterative Detection Durai Thirupathi and Keith M. Chugg  

E-print Network

common UWB system found in the literature, the impulse radio, uses very narrow pulses as a way to expand significantly degrading the perfor- mance. I. INTRODUCTION After the discovery of turbo codes [1], iterative

Southern California, University of

76

Iterative algorithms for multichannel equalization in sound reproduction systems  

Microsoft Academic Search

A fast iterative algorithm, with computation based on the fast Fourier transform (FFT), is presented. It can be used to control a sound field at several control points with a loudspeaker array from multiple reference signals. It designs an equalizer able to invert long FIR filters and which achieves better performance than traditional FFT-based deconvolution methods with an equal number

M. Guillaume; Y. Grenier; G. Richard

2005-01-01

77

Iterative Methods for Systems' Solving - a C# approach  

E-print Network

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

Chirilov, Claudiu

2009-01-01

78

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

79

Iterative receivers for space-frequency block-coded OFDM systems with error propagation suppression  

Microsoft Academic Search

This paper considers the design of iterative receivers for space-frequency block-coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in unknown wireless dispersive fading channel with outer channel coding. The iterative joint channel estimation and symbol detection algorithm is derived. A simple decision-error judgment criterion is proposed and an improved training scheme is applied in the system to suppress the error propagation.

Ya Jing; Xiaodong Xu; Ming Chen; Shixin Cheng; Haifeng Wang

2005-01-01

80

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

81

A framework for iterative analysis of non-classically damped dynamical systems  

NASA Astrophysics Data System (ADS)

In this paper, we propose a general iterative framework to solve the dynamic problem for linear systems with non-classical viscous damping. A systematic approach is used to derive families of stationary iterative schemes that, as an instance of particular interest, decouple the equations of motion for numerical study of the system response. For such schemes, we present a detailed convergence analysis and propose several solution strategies suitable for a broad class of systems. These techniques are based on spectral analysis of particular iteration matrices arising in the derivation and aim at optimizing the convergence performance of the method. We demonstrate that the proposed systematic framework, based on a novel application of the homotopy analysis method, generalizes iterative schemes previously reported in the literature and, importantly, provides a unified perspective for the study of iterative solutions of dynamic problems. Further, we establish a connection between our results and the theory of iterative schemes for algebraic linear systems, thus providing insights on convergence results and applicability of the method. Numerical examples illustrate the effectiveness of the approach and indicate future research directions.

Aureli, Matteo

2014-12-01

82

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

83

Low Complexity Affine MMSE detector for Iterative Detection-Decoding MIMO OFDM system  

Microsoft Academic Search

Iterative turbo processing between detection and decoding shows near-capacity performance on a multiple-antenna system. Combining iterative processing with optimum front-end detection is particularly challenging because the front-end maximum a posteriori (MAP) algorithm has a computational complexity that is exponential in the throughput. Sub-optimum detector such as the soft interference cancellation linear minimum mean square error (SIC-LMMSE) detector with near front-end

Daniel N. Liu; Michael P. Fitz

2006-01-01

84

Low complexity affine MMSE detector for iterative detection-decoding MIMO OFDM systems  

Microsoft Academic Search

Iterative turbo processing between detection and decoding shows near-capacity performance on a multiple-antenna system. Combining iterative processing with optimum front-end detection is particularly challenging because the front-end maximum a posteriori (MAP) algorithm has a computational complexity that is exponential. Sub-optimum detector such as the soft interference cancellation linear minimum mean square error (SIC-LMMSE) detector with near front-end MAP performance has

Daniel N. Liu; Michael P. Fitz

2008-01-01

85

Development of the prototype pneumatic transfer system for ITER neutron activation system  

SciTech Connect

The neutron activation system (NAS) measures neutron fluence at the first wall and the total neutron flux from the ITER plasma, providing evaluation of the fusion power for all operational phases. The pneumatic transfer system (PTS) is one of the key components of the NAS for the proper operation of the system, playing a role of transferring encapsulated samples between the capsule loading machine, irradiation stations, counting stations, and disposal bin. For the validation and the optimization of the design, a prototype of the PTS was developed and capsule transfer tests were performed with the developed system.

Cheon, M. S.; Seon, C. R.; Pak, S.; Lee, H. G. [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Bertalot, L. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

2012-10-15

86

Direct adaptive iterative learning control of nonlinear systems using an output-recurrent fuzzy neural network.  

PubMed

In this paper, a direct adaptive iterative learning control (DAILC) based on a new output-recurrent fuzzy neural network (ORFNN) is presented for a class of repeatable nonlinear systems with unknown nonlinearities and variable initial resetting errors. In order to overcome the design difficulty due to initial state errors at the beginning of each iteration, a concept of time-varying boundary layer is employed to construct an error equation. The learning controller is then designed by using the given ORFNN to approximate an optimal equivalent controller. Some auxiliary control components are applied to eliminate approximation error and ensure learning convergence. Since the optimal ORFNN parameters for a best approximation are generally unavailable, an adaptive algorithm with projection mechanism is derived to update all the consequent, premise, and recurrent parameters during iteration processes. Only one network is required to design the ORFNN-based DAILC and the plant nonlinearities, especially the nonlinear input gain, are allowed to be totally unknown. Based on a Lyapunov-like analysis, we show that all adjustable parameters and internal signals remain bounded for all iterations. Furthermore, the norm of state tracking error vector will asymptotically converge to a tunable residual set as iteration goes to infinity. Finally, iterative learning control of two nonlinear systems, inverted pendulum system and Chua's chaotic circuit, are performed to verify the tracking performance of the proposed learning scheme. PMID:15484908

Wang, Ying-Chung; Chien, Chiang-Ju; Teng, Ching-Cheng

2004-06-01

87

Revisiting the iterative procedure for atomic beam diffraction analyses: improvements, caveats and first application to a 2D adsorption structure  

NASA Astrophysics Data System (ADS)

It is demonstrated that the iterative inversion procedure to deduce corrugation functions from atomic beam diffraction spectra based on the GR method as developed by James et al. [Surf. Sci. 133 (1993) 305; 148 (1984) 72; 173 (1986) 517] can be numerically stabilized by using other root searching procedures than the Newton method. It is also shown that local minima of the reliability factor in parameter space are often approached demonstrating the necessity to use widely different initial parameter sets as well as to analyze diffraction spectra for several angles of incidence and wavelengths. The iterative procedure is applied for the first time to a complicated 2D corrugation: the best-fit corrugation of the H-c(2 × 4) structure on Ni(110) is found even when starting from 1D corrugations.

Gross, G.; Rieder, K. H.

1993-05-01

88

Iterative Spatial Sequence Estimator for Multi-Group Space Time Trellis Coded Systems  

E-print Network

Iterative Spatial Sequence Estimator for Multi-Group Space Time Trellis Coded Systems Samir Al fewer than what V-BLAST algorithm requires. By applying reduced state sequence estimation, complexity for decoding multi-group space time trellis coded systems. These systems consider a single user who transmits

Al-Ghadhban, Samir

89

Design of the Low Density Mixture Liquid Control System Based on Iterative Learning Control Theory  

Microsoft Academic Search

The low density mixture liquid is strict with every component mixed proportion, and its control system requests high control precision. The traditional ratio control system is often unable to realize the ingredient precision control. Taking the iterative learning control theory as the core, this paper designs the ingredient control system combined with the PID control algorithm, which is able to

Ma Hui-hai

2009-01-01

90

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

91

Status of the ITER neutral beam injection system.  

PubMed

The ITER neutral beam injectors are the first injectors to be designed to operate under conditions and constraints similar to those that will be encountered with a fusion reactor. The injectors will use a single large ion source and accelerator that will produce 40 A D(-) 1 MeV beams for pulse lengths of up to 3600 s. The accelerated ion beams will be neutralized in a gas (D(2)) neutralizer which is subdivided into four vertical channels to reduce the gas flow into the injectors that is needed to produce optimum target for neutralization. These injectors will have to operate in a hostile radiation environment and they will become highly radioactive due to the neutron flux from ITER. The design has been modified recently to have a rectangular vacuum vessel with a removable lid that allows vertical access to, and maintenance of, the beamline components, the incorporation of an absolute all metal valve at the exit of the injector, the choice of a rf driven ion source as the reference design of ion source, and to have a high voltage deck incorporating the various auxiliary power supplies in air rather that under high pressure SF(6). A major development is that it has been agreed that a Neutral Beam Test Facility (NBTF) will be set up at Padua, Italy. The NBTF will consist of two test beds: one of which will be capable of operating a complete injector at full performance. The second will be an ion source test bed, which will be used for the development and testing, to full performance, of the large negative ion source. PMID:18315235

Hemsworth, R S; Tanga, A; Antoni, V

2008-02-01

92

Parallel Iterative Solution of Finite Element Systems of Equations Employing EdgeBased Data Structures \\Lambda  

E-print Network

Parallel Iterative Solution of Finite Element Systems of Equations Employing Edge­Based Data gradient solution of finite element systems of equations on unstructured grids composed by triangles or tetrahedra. The optimization techniques are based on the transition from a conventional element­by­element

Coutinho, Alvaro L. G. A.

93

Correction of extrinsic information for iterative decoding in a serially concatenated multiuser DS-CDMA system  

Microsoft Academic Search

ó The system under study is a coded asynchronous DS-CDMA system with orthogonal modulation in time-varying Rayleigh fading multipath channels. Information bits are con- volutionally encoded, block interleaved, and mapped to M - ary orthogonal Walsh codes, where the last step is essentially a process of block coding. This paper aims at tackling the problem of joint iterative decoding of

Pei Xiao; Erik G. Ström

2006-01-01

94

Simulation of an iterative learning control system for fed-batch cell culture processes.  

PubMed

This paper describes an iterative learning control scheme for fed-batch operation where repetitive trajectory tracking tasks are required. The proposed learning strategy is model-independent, and it takes advantage of the repetitive feature of system operations with a certain degree of intelligence and requires only small size of dynamic database for the learning process. The convergence of the learning process is proven. An example of simultaneously tracking two predefined trajectories by iterative learning control with two control inputs is given to illustrate the methodology. Satisfactory performance of the learning system can be observed from the simulation results. PMID:1369105

Fu, P; Barford, J P

1992-01-01

95

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

96

An iterative scheme for LMI-based robust pole assignment with control input saturation constraints for uncertain LTI systems  

Microsoft Academic Search

In the present article, an iterative scheme for placing the poles of the closed loop system inside an LMI-region for a continuous system with parametric uncertainties and control input saturation constraints, is proposed. The objective is to reduce the size of the LMI-region in order to address the performance of the system. An iterative scheme that starts from the Left

Marialena Vagia; Anthony Tzes

2011-01-01

97

Iterative Learning Control Systems Based on Inverse Systems and Interactor Matrix for Linear Discrete-time Systems  

NASA Astrophysics Data System (ADS)

In this paper, it will be clear the structure of the Iterative Learning Control (ILC) based on the inverse system. Moore-Penrose pseudo-inverse of a Toeplitz matrix will be investigated to analyze the learning gain matrix and will be derived the cascade controller transfer function matrix. From these investigations, the critical points of ILC based on the gradient will be issued.

Kase, Wataru

98

US ITER Moving Forward  

ScienceCinema

US ITER Project Manager Ned Sauthoff, joined by Wayne Reiersen, Team Leader Magnet Systems, and Jan Berry, Team Leader Tokamak Cooling System, discuss the U.S.'s role in the ITER international collaboration.

US ITER / ORNL

2012-03-16

99

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

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

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

1994-04-01

100

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

101

Initial results of systems analysis of the ITER design space  

SciTech Connect

This series of vugraphs presents preliminary analyses of various design points for the next generation thermonuclear test reactor. The authors state that constrained optimization of a figure-of-merit leads to acceptable design points. Design points discussed include: device radius, aspect ratio, magnetic field strength, magnet current, plasma current, and ignition margin. (JDH)

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

1987-01-01

102

Error Propagation Mitigation for Iterative Channel Tracking, Detection and Decoding of BICM-OFDM Systems  

Microsoft Academic Search

We present a novel method to reduce error- propagation in iterative receivers of BICM-OFDM systems under fast fading channels. The effect of symbols misdetection on channel tracking is studied and a novel solution to combat the performance degradation is suggested. In general, for blind channel tracking, the use of the detected symbols is required. However, as we show in this

Ido Nevat; Jinhong Yuan

2007-01-01

103

Systems of iterated projective ordinal notations and combinatorial statements about binary labeled trees  

Microsoft Academic Search

We introduce the appropriate iterated version of the system of ordinal notations from [G1] whose order type is the familiar Howard ordinal. As in [G1], our ordinal notations are partly inspired by the ideas from [P] where certain crucial properties of the traditional Munich' ordinal notations are isolated and used in the cut-elimination proofs. As compared to the corresponding “impredicative”

L. Gordeev

1989-01-01

104

Iterative Solution of Algebraic Riccati Equations for Damped Systems Kirsten Morris and Carmeliza Navasca  

E-print Network

Iterative Solution of Algebraic Riccati Equations for Damped Systems Kirsten Morris and Carmeliza Navasca Abstract-- Algebraic Riccati equations (ARE) of large dimen- sion arise when using approximations-known that the solution to this problem is found by solving an algebraic Riccati equation A P + PA - PBR-1 B P = -Q. (2

Soatto, Stefano

105

LETTER TO THE EDITOR: Iterative perturbation theory for strongly correlated electron systems with orbital degeneracy  

Microsoft Academic Search

A new scheme of the iterative perturbation theory is proposed for the strongly correlated electron systems with orbital degeneracy. The method is based on the modified self-energy of Yeyati et al (Phys. Rev. Lett. 1999 83 600) which interpolates between the weak and the strong correlation limits, but here a much simpler scheme is proposed which is useful in the

Tetsuro Saso

2001-01-01

106

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

Microsoft Academic Search

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

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

1995-01-01

107

Adaptive Iterative Learning Control of Time-delay Nonlinear Output-feedback Systems  

Microsoft Academic Search

In this paper, an adaptive tracking controller for a class of time-delay output feedback nonlinear systems is first proposed, an adaptive iterative learning control is then designed for repetitive time-delay output-feedback systems. The global exactly tracking on the specified time interval and the boundedness of all signals of the learning system are given via using the measurement output. In addition,

Junmin Li; Daniel W. C. Ho

2003-01-01

108

Reset-free Iterative Learning Control and Its Application to Continuous-time System Identification  

NASA Astrophysics Data System (ADS)

This paper proposes a new approach for the projection type iterative learning control (ILC) with an application to identification of continuous-time systems. First, this paper gives a framework to perform ILC without resetting the initial condition at each iteration, which can be achieved by introducing the dynamics into the system representation in the finite-dimensional signal subspace. Second, it is shown how to identify the system parameters based on the proposed ILC. The method does not require us to wait for the equilibrium state patiently or reset the system forcibly in the identification process. Furthermore, a class of gain decreasing filters are introduced. Combination of these results gives us the estimates which converge to the true system parameters against measurement noise. A numerical example is given to demonstrate these properties of the proposed method.

Maruta, Ichiro; Sugie, Toshiharu

109

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

110

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

111

Conceptual design of an electron cyclotron wave system for NET/ITER  

NASA Astrophysics Data System (ADS)

A detailed study of the 120 GHz/20 MW ITER (International Thermonuclear Experimental Reactor) reference is presented. Scaling rules and additional antenna designs for higher frequency systems were developed. The design principle was to offer a high degree of flexibility for the wide range of envisaged uses of the Electron Cyclotron Waves (ECWs). The efficiency of the ECW system is estimated to be between 25 and 40 percent, depending mainly on the efficiency of the gyrotrons. An evaluation of the costs is given. The technical programs of the transmission components of the transmission line and antenna for the ITER 120 to 140 GHz ECW system are concluded to be solvable with today's technology. For other ECW heating and current drive applications, this system can be scaled in power and frequency.

Kasparek, W.; Kumric, H.; Mueller, G. A.; Pretterebner, J.; Schueller, P. G.; Wagner, D.

1991-07-01

112

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

113

Control of non-controllable quantum systems: A quantum control algorithm based on Grover iteration  

E-print Network

A new notion of controllability, eigenstate controllability, is defined for finite-dimensional bilinear quantum mechanical systems which are neither strongly completely controllably nor completely controllable. And a quantum control algorithm based on Grover iteration is designed to perform a quantum control task of steering a system, which is eigenstate controllable but may not be (strongly) completely controllable, from an arbitrary state to a target state.

Chen-Bin Zhang; Dao-Yi Dong; Zong-Hai Chen

2005-03-02

114

Iterative built-in testing and tuning of mixed-signal\\/RF systems  

Microsoft Academic Search

Design and test of high-speed mixed-signal\\/RF circuits and systems is undergoing a transformation due to the effects of process variations stemming from the use of scaled CMOS technologies that result in significant yield loss. To this effect, post-manufacture tuning for yield recovery is now a necessity for many high-speed electronic circuits and systems and is typically driven by iterative test-and-tune

A. Chatterjee; D. Han; V. Natarajan; S. Devarakond; S. Sen; H. Choi; R. Senguttuvan; S. Bhattacharya; A. Goyal; D. Lee; M. Swaminathan

2009-01-01

115

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

Microsoft Academic Search

ITER inductive power operation is modeled and simulated using a thermal-hydraulics system code (RELAP5) integrated with a 3-D CFD (SC-Tetra) code. The Primary Heat Transfer System (PHTS) functions are predicted together with the main parameters operational ranges. The control algorithm strategy and derivation are summarized as well. The First Wall and Blanket modules are the primary components of PHTS, used

Alice Ying; Emilian L Popov

2011-01-01

116

Iterative learning control for nonlinearly parameterized systems with unknown control direction  

NASA Astrophysics Data System (ADS)

An iterative learning controller is presented for nonlinearly parameterized uncertain systems with unknown control direction. By using the parameter separation technique and the signal replacement mechanism, the system equation is reconstructed. By using the Nussbaum function, the proposed control laws can guarantee that all the signals in the closed-loop are bounded and the tracking error converges to zero over the entire interval. The numerical simulation is carried out to demonstrate effectiveness of the presented learning schemes.

Yan, Qiuzhen; Wang, Hongfa; Yu, Feng

117

Decentralized Iterative Learning Controllers for Nonlinear Large-scale Systems to Track Trajectories with Different Magnitudes  

Microsoft Academic Search

In hierarchical steady-state optimization programming for large-scale industrial processes, a feasible technique is to use information of the real system so as to modify the model-based optimum. In this circumstance, a sequence of step function-type control decisions with distinct magnitudes is computed, by which the real system is stimulated consecutively. In this paper, a set of iterative learning controllers is

Xiao-E RUAN; Feng-Min CHEN; Bai-Wu WAN

2008-01-01

118

An extensible analysable system model5 Christian W. Probsta,  

E-print Network

analyses techniques. In this paper we present an approach to both formalising those real-world systems University of Denmark, Denmark b Aalborg University, Aalborg, Denmark a b s t r a c t Analysing real-world systems for vulnerabilities with respect to security and safety threats is a difficult undertaking

Hansen, René Rydhof

119

Pole placement and order reduction in two-time-scale control systems through Riccati iteration  

NASA Technical Reports Server (NTRS)

A transformation of variables taken from singular perturbations may be applied to two-time-scale linear systems in state space form to reduce the system to block-diagonal form with slow and fast modes decoupled. The transformation is easily computed by applying the new Riccati iteration. The iteration yields a solution to the nonsymmetric algebraic Riccati equation obtained by partitioning the original system matrix A. The numerical procedure is initiated with the trivial iterate L(0) = 0, and is globally convergent to the desired unique time scale decoupling solution. After transformation, the decoupled system may be used in controller design to achieve exact closed loop pole placement in the slow subsystem without altering the poles of the fast subsystem. The decoupled form may also be used to reduce system order by wetting a small parameter to zero. Provided the fast subsystem is stable, the order reduction can be expected to yield a good approximation to the original system. These methods are demonstrated using the 16th order linear model of a turbofan engine.

Anderson, L. R.

1982-01-01

120

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...

121

Power Measurements and Analyses of Massive Object Storage System  

Microsoft Academic Search

With the increase of high performance computing systems' scale, the power consumption of HPC systems greatly increase, among which the power consumption of massive storage system occupies an important role. Measurements and analyses of massive storage system are significant for reducing the power consumption of storage system. Tianhe-1 comes in at No.5 in Nov. 2009 Top500 list with the highest

Yong Dong; Juan Chen; Tao Tang

2010-01-01

122

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

123

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

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

1994-04-01

124

Design of the Remote Steerable ECRH launching system for the ITER upper ports  

NASA Astrophysics Data System (ADS)

An ECRH (electron-cyclotron resonance heating) launching system for the ITER upper ports is being designed. The aim of the system is to inject Electron Cyclotron Waves (ECW) in the ITER plasma in order to stabilize neoclassical tearing modes (NTM). Each of the four upper-port launchers consists of six mm-wave lines capable of transmitting high power up to 2 MW per line at 170 GHz. In order to exploit the capability of ECW for localized heating and current drive over a range of plasma radii in ITER, the ECH&CD upper port launcher must have a beam steering capability. The Remote Steering (RS) principle has great advantages, because it enables to avoid steerable mirrors with flexible cooling lines at the plasma-facing end of the launcher. The principle consists of a long, corrugated, square waveguide having the steerable optics placed outside of the first confinement boundary of the vacuum vessel. All vulnerable components are far away from the hostile plasma environment. Furthermore, the RS launching system enables to do maintenance on the system during shutdown, without affecting the torus vacuum and the blanket cooling circuits.

Verhoeven, A. G. A.; Elzendoorn, B. S. Q.; Bongers, W. A.; Bruschi, A.; Cirant, S.; Danilov, I.; Fernandez, A.; Gantenbein, G.; Graswinckel, M. F.; Heidinger, R.; Kasparek, W.; Kleefeldt, K.; Kruijt, O. G.; Lamers, B.; Piosczyk, B.; Plaum, B.; Ronden, D. M. S.; Saibene, G.; Zohm, H.

2005-01-01

125

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

NASA Astrophysics Data System (ADS)

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

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

2014-06-01

126

Iterative learning-based decentralized adaptive tracker for large-scale systems: a digital redesign approach.  

PubMed

In this paper, a digital redesign methodology of the iterative learning-based decentralized adaptive tracker is proposed to improve the dynamic performance of sampled-data linear large-scale control systems consisting of N interconnected multi-input multi-output subsystems, so that the system output will follow any trajectory which may not be presented by the analytic reference model initially. To overcome the interference of each sub-system and simplify the controller design, the proposed model reference decentralized adaptive control scheme constructs a decoupled well-designed reference model first. Then, according to the well-designed model, this paper develops a digital decentralized adaptive tracker based on the optimal analog control and prediction-based digital redesign technique for the sampled-data large-scale coupling system. In order to enhance the tracking performance of the digital tracker at specified sampling instants, we apply the iterative learning control (ILC) to train the control input via continual learning. As a result, the proposed iterative learning-based decentralized adaptive tracker not only has robust closed-loop decoupled property but also possesses good tracking performance at both transient and steady state. Besides, evolutionary programming is applied to search for a good learning gain to speed up the learning process of ILC. PMID:21333988

Tsai, Jason Sheng-Hong; Du, Yan-Yi; Huang, Pei-Hsiang; Guo, Shu-Mei; Shieh, Leang-San; Chen, Yuhua

2011-07-01

127

Modeling heterogeneous and fractured reservoirs with inverse methods based on iterated function systems  

SciTech Connect

Fractured and heterogeneous reservoirs are complex and difficult to characterize. In many cases, the modeling approaches used for making predictions of behavior in such reservoirs have been unsatisfactory. In this paper we describe a new modeling approach which results in a model that has fractal-like qualities. This is an inverse approach which uses observations of reservoir behavior to create a model that can reproduce observed behavior. The model is described by an iterated function system (IFS) that creates a fractal-like object that can be mapped into a conductivity distribution. It may be possible to identify subclasses of Iterated Function Systems which describe geological facies. By limiting the behavior-based search for an IFS to the geologic subclasses, we can condition the reservoir model on geologic information. This technique is under development, but several examples provide encouragement for eventual application to reservoir prediction.

Long, J.C.S.; Doughty, C.; Hestir, K.; Martel, S.

1992-05-01

128

Toward the iterative learning control for belt-driven system using wavelet transformation  

NASA Astrophysics Data System (ADS)

An iterative learning scheme using wavelet transformation to achieve excellent speed-tracking performance of a belt-driven system is presented in this article. The learning control scheme consists of a proportional feedback controller and a feedforward controller. The learning law updates the control profile from the previous output signal of the feedback controller, which has been processed via the wavelet transformation. Using wavelet transformation, the adverse effect due to unlearnable system dynamics can be drastically attenuated. The convergence of the learning control scheme is thus theoretically guaranteed and the convergent rate can be greatly improved in comparison to other iterative learning schemes. The proposed scheme is applied to the speed tracking for an ink-jet printer and excellent speed-tracking performance is achieved through experimental verification.

Tzeng, Kune-Shiang; Chen, Jian-Shiang

2005-09-01

129

Adaptive iterated function systems filter for images highly corrupted with fixed - Value impulse noise  

NASA Astrophysics Data System (ADS)

The Adaptive Iterated Functions Systems (AIFS) Filter presented in this paper has an outstanding potential to attenuate the fixed-value impulse noise in images. This filter has two distinct phases namely noise detection and noise correction which uses Measure of Statistics and Iterated Function Systems (IFS) respectively. The performance of AIFS filter is assessed by three metrics namely, Peak Signal-to-Noise Ratio (PSNR), Mean Structural Similarity Index Matrix (MSSIM) and Human Visual Perception (HVP). The quantitative measures PSNR and MSSIM endorse the merit of this filter in terms of degree of noise suppression and details/edge preservation respectively, in comparison with the high performing filters reported in the recent literature. The qualitative measure HVP confirms the noise suppression ability of the devised filter. This computationally simple noise filter broadly finds application wherein the images are highly degraded by fixed-value impulse noise.

Shanmugavadivu, P.; Eliahim Jeevaraj, P. S.

2014-06-01

130

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

Microsoft Academic Search

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

K. Takahashi; K. Kajiwara; Y. Oda; A. Kasugai; N. Kobayashi; K. Sakamoto; J. Doane; R. Olstad; M. Henderson

2011-01-01

131

Transmit beamforming and iterative water-filling based on SLNR for OFDMA systems  

Microsoft Academic Search

This paper proposes a transmit beamforming and subcarrier power allocation method for orthogonal frequency division multiple access (OFDMA) systems based on ¿signal-to-leakage-plus-noise ratio¿ (SLNR). As the transmit beamforming vector control criterion, we employ the maximization of the SLNR at each base station, while the subcarrier power allocation is performed by iterative water-filling algorithm using the SLNR of each subcarrier. The

Kazunori Hayashi; Megumi Kaneko; Takeshi Fujii; Hideaki Sakai; Yoji Okada

2009-01-01

132

An iterative decoding technique and architecture for RS concatenated TCM coding systems  

Microsoft Academic Search

In this paper, we propose a soft value modification (SVM) algorithm, based on which we further propose a new low-complexity iterative decoding technique for the conventional serial concatenated coding system which consists of Reed-Solomon (RS) code and Trellis coded Modulation (TCM) scheme with an interleaver in between. In our decoding technique, the RS decoder is based on Berlekamp-Massey (BM) algorithm,

Lin Gui; Yin Xu; Bo Liu; Liang Gong; Ying Li

2010-01-01

133

Lithium test module on ITER: engineering design of the tritium recovery system  

SciTech Connect

The design presented is an overview of the tritium recovery system for a lithium module on an ITER type reactor. The design of a tritium recovery system for larger blanket units, sectors, etc. could use the information developed in this report. A goal of this design was to ensure that a reliable, integrated performance of the tritium recovery system could be demonstrated. An equally important goal was to measure and account for the tritium in the liquid lithium blanket module and its recovery system in order to validate the operation of the blanket module.

Finn, P.A.

1988-01-01

134

Characterization of fast microchannel plate photomultipliers for the ITER core LIDAR Thomson scattering system  

NASA Astrophysics Data System (ADS)

In the new ITER core LIDAR Thomson scattering system under development, detectors with pulse response as low as 330 ps and 10 mm diameter active area, covering with good sensitivity the spectral range 380-1100 nm will be necessary. For the visible region 400-750 nm, fast microchannel plate photomultipliers with a GaAsP photocathode that fulfill the characteristics of speed, sensitivity and active area are already commercially available and have been recently characterized for operation in the JET edge LIDAR Thomson scattering system. In this paper we present a further characterization of these devices to evaluate their usefulness in the more demanding operating conditions of the ITER core LIDAR Thomson scattering system. The characteristics of these detectors with regard to linearity, gain recovery time, pulse repetition rate, quantum efficiency and response time for large F-number illumination, have been measured. Linearity and recovery time data have been interpreted according to a new, time dependent, microchannel plate operational model. The results show that these detectors are suitable also for use in ITER.

Giudicotti, L.; Pasqualotto, R.

2012-02-01

135

Modelling Adaptive Dynamical Systems to Analyse Eating Regulation Disorders  

E-print Network

Modelling Adaptive Dynamical Systems to Analyse Eating Regulation Disorders Tibor Bosse1 , Martine, an executable model has been developed of the dynamics of eating regulation disorders. Based on this model, The Netherlands Abstract. To analyse the disorders of their patients, psychotherapists often have to get insight

Treur, Jan

136

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

NASA Astrophysics Data System (ADS)

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

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

2007-01-01

137

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

138

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

PubMed

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°-40° 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. PMID:21721690

Takahashi, K; Kajiwara, K; Oda, Y; Kasugai, A; Kobayashi, N; Sakamoto, K; Doane, J; Olstad, R; Henderson, M

2011-06-01

139

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

NASA Astrophysics Data System (ADS)

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°-40° 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.; Doane, J.; Olstad, R.; Henderson, M.

2011-06-01

140

Newton iterative methods for large scale nonlinear systems. Progress report, 1992--1993  

SciTech Connect

Objective is to develop robust, efficient Newton iterative methods for general large scale problems well suited for discretizations of partial differential equations, integral equations, and other continuous problems. A concomitant objective is to develop improved iterative linear algebra methods. We first outline research on Newton iterative methods and then review work on iterative linear algebra methods. (DLC)

Walker, H.F.; Turner, K.

1993-06-01

141

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

142

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

SciTech Connect

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

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

2011-01-01

143

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

144

Mechanical property tests on structural materials for ITER magnet system at low temperatures in China  

NASA Astrophysics Data System (ADS)

High field superconducting magnets need strong non-superconducting components for structural reinforcement. For instance, the ITER magnet system (MS) consists of cable-in-conduit conductor, coil case, magnet support, and insulating materials. Investigation of mechanical properties at magnet operation temperature with specimens machined at the final manufacturing stages of the conductor jacket materials, magnet support material, and insulating materials, even the component of the full-size conductor jacket is necessary to establish sound databases for the products. In China, almost all mechanical property tests of structural materials for the ITER MS, including conductor jacket materials of TF coils, PF coils, CCs, case material of CCs, conductor jacket materials of Main Busbars (MB) and Corrector Busbars (CB), material of magnet supports, and insulating materials of CCs have been carried out at the Technical Institute of Physics and Chemistry (TIPC), Chinese Academy of Sciences (CAS). In this paper, the mechanical property test facilities are briefly demonstrated and the mechanical tests on the structural materials for the ITER MS, highlighting test rigs as well as test methods, are presented.

Huang, Chuanjun; Huang, Rongjin; Li, Laifeng

2014-01-01

145

Identification of Multivariable Continuous-time Systems via Projection Type Iterative Learning  

NASA Astrophysics Data System (ADS)

This paper presents an identification method based on an iterative learning control (ILC) concepts for the multivariable continuous-time systems.For this purpose, a projection type ILC which updates the input in an appropriate parameter space is extended to the case of multivariable systems.The robustness against measurement noise is achieved through both projection of continuous-time I/O signals onto a finite dimensional space and noise tolerant learning algorithms. Finally, a numerical example demonstrate how the parameter estimation can be achieved through the proposed identification method in the presence of heavy measurement noises.

Sakai, Fumitoshi; Sugie, Toshiharu

146

Models Extracted from Text for System-Software Safety Analyses  

NASA Technical Reports Server (NTRS)

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

Malin, Jane T.

2010-01-01

147

DEVELOPMENT OF TRAFFIC IMAGE ANALYSING SYSTEM FOR MOBILE TERMINALS USING  

E-print Network

-gun, Shimane 690-0331, Japan s-adachi@mx2.kc-net.ne.jp Abstract Traffic monitoring using CCTV is rapidly the reduction of traffic congestion. The captured CCTV images are provided to the analysing system via Internet developing for Nottingham city traffic. The CCTV monitoring systems are now very popular all over the world

Bargiela, Andrzej

148

Low complexity linear MMSE detector with recursive update algorithm for iterative detection-decoding MIMO OFDM system  

Microsoft Academic Search

Iterative turbo processing between detection and decoding shows near-capacity performance on a multiple-antenna system. Combining iterative processing with optimum front-end detection is particularly challenging because the front-end maximum a posteriori (MAP) algorithm has a computational complexity that is exponential in the throughput. Sub-optimum detector such as the soft interference cancellation linear minimum mean square error (SIC-LMMSE) detector with near front-end

Daniel N. Liu; Michael P. Fitz

2006-01-01

149

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

E-print Network

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

Dai, Huaiyu

150

A protection system for the JET ITER-like wall based on imaging diagnosticsa)  

NASA Astrophysics Data System (ADS)

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.

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.; JET-EFDA Contributors

2012-10-01

151

Annual Report of the EURATOM/UKAEA Fusion Programme 2007/08 8 ITER Systems  

E-print Network

of welding techniques for the ITER Vacuum Vessel. There has also been work by Durham University contributions on the standards needed for diagnostic windows on ITER, and with Cranfield University a study characterising superconducting strand to be used in ITER magnets. The status and progress on all these studies

152

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

SciTech Connect

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

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

2011-01-01

153

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

154

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

155

LSRN: A PARALLEL ITERATIVE SOLVER FOR STRONGLY OVER- OR UNDERDETERMINED SYSTEMS*  

PubMed Central

We describe a parallel iterative least squares solver named LSRN that is based on random normal projection. LSRN computes the min-length solution to minx??n ?Ax ? b?2, where A ? ?m × n with m ? n or m ? n, and where A may be rank-deficient. Tikhonov regularization may also be included. Since A is involved only in matrix-matrix and matrix-vector multiplications, it can be a dense or sparse matrix or a linear operator, and LSRN automatically speeds up when A is sparse or a fast linear operator. The preconditioning phase consists of a random normal projection, which is embarrassingly parallel, and a singular value decomposition of size ?? min(m, n)? × min(m, n), where ? is moderately larger than 1, e.g., ? = 2. We prove that the preconditioned system is well-conditioned, with a strong concentration result on the extreme singular values, and hence that the number of iterations is fully predictable when we apply LSQR or the Chebyshev semi-iterative method. As we demonstrate, the Chebyshev method is particularly efficient for solving large problems on clusters with high communication cost. Numerical results show that on a shared-memory machine, LSRN is very competitive with LAPACK’s DGELSD and a fast randomized least squares solver called Blendenpik on large dense problems, and it outperforms the least squares solver from SuiteSparseQR on sparse problems without sparsity patterns that can be exploited to reduce fill-in. Further experiments show that LSRN scales well on an Amazon Elastic Compute Cloud cluster.

Meng, Xiangrui; Saunders, Michael A.; Mahoney, Michael W.

2014-01-01

156

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

SciTech Connect

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

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

2011-01-01

157

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

NASA Technical Reports Server (NTRS)

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

Deuflhard, Peter; Freund, Roland; Walter, Artur

1990-01-01

158

Proposal of Adaptive Type Iterative Learning Control for System with Characteristic Change  

NASA Astrophysics Data System (ADS)

Authors proposed the machine control technique for manipulating man's condition by the iterative learning control (ILC) based on the biomedical signal. However, there was a possibility that ILC becomes unstable when the system with low repeatability like man was included in controlled object. Then, “Adaptive type ILC (ATILC)” that adjusted the learning gain according to the characteristic change of controlled object at each trial was newly proposed in this paper. The ATILC adjusts learning gain by using the model parameter after controlled object is modeled by first-order delay based on the time series of I/O in one trial of controlled object. Even if controlled system is accompanied by the property change, the output trajectory of controlled object follows to objective one by ATILC. The effectiveness of the proposed method was confirmed by simulation work by using the approximation model of biological signal.

Imai, Atsufumi; Kushida, Daisuke; Takemori, Fumiaki; Kitamura, Akira

159

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

NASA Astrophysics Data System (ADS)

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

Saha, Krishnendu; Straus, Kenneth J.; Chen, Yu.; Glick, Stephen J.

2014-08-01

160

Compartment Venting Analyses of Ares I First Stage Systems Tunnel  

NASA Technical Reports Server (NTRS)

Compartment venting analyses have been performed for the Ares I first stage systems tunnel using both the lumped parameter method and the three-dimensional (31)) transient computational fluid dynamics (CFD) approach. The main objective of venting analyses is to predict the magnitudes of differential pressures across the skin so the integrity of solid walls can be evaluated and properly designed. The lumped parameter method assumes the gas pressure and temperature inside the systems tunnel are spatially uniform, which is questionable since the tunnel is about 1,700 in. long and 4 in. wide. Therefore, 31) transient CFD simulations using the commercial CFD code FLUENT are performed in order to examine the gas pressure and temperature variations inside the tunnel. It was found that the uniform pressure and temperature assumptions inside the systems tunnel are valid during ascent. During reentry, the uniform pressure assumption is also reasonable but the uniform temperature assumption is not valid. Predicted pressure and temperature inside the systems tunnel using CFD are also compared with those from the lumped parameter method using the NASA code CHCHVENT. In general, the average pressure and temperature inside the systems tunnel from CFD are between the burst and crush results from CHCHVENT during both ascent and reentry. The skin differential pressure and pressure inside the systems tunnel relative to freestream pressure from CHCHVENT as well as velocity vectors and streamlines are also discussed in detail.

Wang, Qunzhen; Arner, Stephen

2009-01-01

161

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

162

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

NASA Astrophysics Data System (ADS)

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.

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

163

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

164

Studies on the behaviour of tritium in components and structure materials of tritium confinement and detritiation systems of ITER  

NASA Astrophysics Data System (ADS)

Confinement and the removal of tritium are key subjects for the safety of ITER. The ITER buildings are confinement barriers of tritium. In a hot cell, tritium is often released as vapour and is in contact with the inner walls. The inner walls of the ITER tritium plant building will also be exposed to tritium in an accident. The tritium released in the buildings is removed by the atmosphere detritiation systems (ADS), where the tritium is oxidized by catalysts and is removed as water. A special gas of SF6 is used in ITER and is expected to be released in an accident such as a fire. Although the SF6 gas has potential as a catalyst poison, the performance of ADS with the existence of SF6 has not been confirmed as yet. Tritiated water is produced in the regeneration process of ADS and is subsequently processed by the ITER water detritiation system (WDS). One of the key components of the WDS is an electrolysis cell. To overcome the issues in a global tritium confinement, a series of experimental studies have been carried out as an ITER R&D task: (1) tritium behaviour in concrete; (2) the effect of SF6 on the performance of ADS and (3) tritium durability of the electrolysis cell of the ITER-WDS. (1) The tritiated water vapour penetrated up to 50 mm into the concrete from the surface in six months' exposure. The penetration rate of tritium in the concrete was thus appreciably first, the isotope exchange capacity of the cement paste plays an important role in tritium trapping and penetration into concrete materials when concrete is exposed to tritiated water vapour. It is required to evaluate the effect of coating on the penetration rate quantitatively from the actual tritium tests. (2) SF6 gas decreased the detritiation factor of ADS. Since the effect of SF6 depends closely on its concentration, the amount of SF6 released into the tritium handling area in an accident should be reduced by some ideas of arrangement of components in the buildings. (3) It was expected that the electrolysis cell of the ITER-WDS could endure 3 years' operation under the ITER design conditions. Measuring the concentration of the fluorine ions could be a promising technique for monitoring the damage to the electrolysis cell.

Kobayashi, K.; Isobe, K.; Iwai, Y.; Hayashi, T.; Shu, W.; Nakamura, H.; Kawamura, Y.; Yamada, M.; Suzuki, T.; Miura, H.; Uzawa, M.; Nishikawa, M.; Yamanishi, T.

2007-12-01

165

Database system for analysing and managing coiled tubing drilling data  

NASA Astrophysics Data System (ADS)

This study present a prototype of database system for analysing and managing petrophysical data from coiled tubing drilling in the oil and gas industry. The characteristics of coiled tubing drilling data from cores were analyzed and categorized according to the whole drilling process and data modeling including object relation diagram, class diagram was carried out to design the schema of effective database system such as the relationships between tables and key index fields to create the relationships. The database system called DrillerGeoDB consists of 22 tables and those are classified with 4 groups such as project information, stratum information, drilling/logging information and operation evaluate information. DrillerGeoDB provide all sort of results of each process with a spreadsheet such as MS-Excel via application of various algorithm of logging theory and statistics function of cost evaluation. This presentation describes the details of the system development and implementation.

Suh, J.; Choi, Y.; Park, H.; Choe, J.

2009-05-01

166

Local identification analyses of soils and soil-structure systems  

NASA Astrophysics Data System (ADS)

Geotechnical structures and natural deposits are massive multi-phase particulate systems characterized by the development of localized response mechanisms under extreme loading conditions. A thorough monitoring of the whole response of such massive and distributed soil-systems commonly constitutes a significant challenge and would be prohibitively expensive. Identification and analysis of these systems based on inverse boundary value problem formulations and sparse measurements are generally overly indeterminate. This study presents an alternative inverse problem algorithm to evaluate the local response mechanisms of soil-systems. Point-wise identification analyses of the constitutive behavior of water-saturated geotechnical and geophysical systems are performed using acceleration and pore pressure records provided by a cluster of closely spaced instruments. The developed algorithm consists of: (1) estimation of strain-time histories using the motions recorded by the cluster, (2) evaluation of stress-time histories corresponding to the estimated strains employing a pre-selected class of constitutive models of soil response, (3) computation of accelerations associated with the estimated stresses and recorded pore-water pressures utilizing the equilibrium equations, and (4) evaluation and calibration of an optimal model of soil response by minimizing the discrepancies between recorded and computed accelerations. The developed novel algorithm does not require the availability of boundary condition measurements, or solution of an associated boundary value problem. The constitutive behavior at a specific location of a soil-system is analyzed independently of adjacent response mechanisms or properties. Computer simulations and downhole array records of Lotung (Taiwan) site were used to assess the validity of the proposed technique for level sites and infinite slopes, under conditions of vertical seismic wave propagation. Numerical simulations and centrifuge test data of a quay wall-soil system were employed to demonstrate the capabilities of the developed algorithm in multi-dimensional situations. Results of the identification analyses showed that the proposed technique provides an effective tool to identify local dynamic soil characteristics and properties.

Oskay, Caglar

167

A Design of Discrete-Time Multivariable Iterative Learning Control Systems with Interactor Matrix  

NASA Astrophysics Data System (ADS)

In this paper, it is proposed a discrete-time multivariable iterative learning control algorithm which guarantees the monotonic convergence of the tracking error norms along with the trial. It is pointed out that an interactor matrix plays an important role in the iterative learning control. Numerical simulations will be presented to confirm the validity of the proposed design.

Kase, Wataru

168

Self-calibration method without joint iteration for distributed small satellite SAR systems  

NASA Astrophysics Data System (ADS)

The performance of distributed small satellite synthetic aperture radar systems degrades significantly due to the unavoidable array errors, including gain, phase, and position errors, in real operating scenarios. In the conventional method proposed in (IEEE T Aero. Elec. Sys. 42:436-451, 2006), the spectrum components within one Doppler bin are considered as calibration sources. However, it is found in this article that the gain error estimation and the position error estimation in the conventional method can interact with each other. The conventional method may converge to suboptimal solutions in large position errors since it requires the joint iteration between gain-phase error estimation and position error estimation. In addition, it is also found that phase errors can be estimated well regardless of position errors when the zero Doppler bin is chosen. In this article, we propose a method obtained by modifying the conventional one, based on these two observations. In this modified method, gain errors are firstly estimated and compensated, which eliminates the interaction between gain error estimation and position error estimation. Then, by using the zero Doppler bin data, the phase error estimation can be performed well independent of position errors. Finally, position errors are estimated based on the Taylor-series expansion. Meanwhile, the joint iteration between gain-phase error estimation and position error estimation is not required. Therefore, the problem of suboptimal convergence, which occurs in the conventional method, can be avoided with low computational method. The modified method has merits of faster convergence and lower estimation error compared to the conventional one. Theoretical analysis and computer simulation results verified the effectiveness of the modified method.

Xu, Qing; Liao, Guisheng; Liu, Aifei; Zhang, Juan

2013-12-01

169

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

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

170

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

SciTech Connect

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

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

2014-01-01

171

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

172

Convergence Analysis and Numerical Study of a Fixed-Point Iterative Method for Solving Systems of Nonlinear Equations  

PubMed Central

We present a fixed-point iterative method for solving systems of nonlinear equations. The convergence theorem of the proposed method is proved under suitable conditions. In addition, some numerical results are also reported in the paper, which confirm the good theoretical properties of our approach. PMID:24795537

Huang, Na

2014-01-01

173

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

PubMed Central

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

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

2011-01-01

174

Data-driven control for relative degree systems via iterative learning.  

PubMed

Iterative learning control (ILC) is a kind of effective data-driven method that is developed based on online and/or offline input/output data. The main purpose of this paper is to supply a unified 2-D analysis approach for both continuous-time and discrete-time ILC systems with relative degree. It is shown that the 2-D Roesser system framework can be established for general ILC systems regardless of relative degree, under which convergence conditions can be provided to guarantee both asymptotic stability and monotonic convergence of the ILC processes. In particular, conditions for the monotonic convergence of ILC can be given in terms of linear matrix inequalities, and formulas for the updating law can be derived simultaneously. Simulation results are presented to illustrate the effectiveness of ILC determined through the 2-D design approach in dealing with the higher order relative degree problem of ILC systems, as well as the robustness of such ILC against uncertainties. PMID:22113776

Meng, Deyuan; Jia, Yingmin; Du, Junping; Yu, Fashan

2011-12-01

175

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

176

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

177

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

178

Appropriate time scales for nonlinear analyses of deterministic jump systems  

NASA Astrophysics Data System (ADS)

In the real world, there are many phenomena that are derived from deterministic systems but which fluctuate with nonuniform time intervals. This paper discusses the appropriate time scales that can be applied to such systems to analyze their properties. The financial markets are an example of such systems wherein price movements fluctuate with nonuniform time intervals. However, it is common to apply uniform time scales such as 1-min data and 1-h data to study price movements. This paper examines the validity of such time scales by using surrogate data tests to ascertain whether the deterministic properties of the original system can be identified from uniform sampled data. The results show that uniform time samplings are often inappropriate for nonlinear analyses. However, for other systems such as neural spikes and Internet traffic packets, which produce similar outputs, uniform time samplings are quite effective in extracting the system properties. Nevertheless, uniform samplings often generate overlapping data, which can cause false rejections of surrogate data tests.

Suzuki, Tomoya

2011-06-01

179

Modeling and Analysis of Alternative Concept of ITER Vacuum Vessel Primary Heat Transfer System  

SciTech Connect

A RELAP5-3D model of the ITER (Latin for the way ) vacuum vessel (VV) primary heat transfer system has been developed to evaluate a proposed design change that relocates the heat exchangers (HXs) from the exterior of the tokamak building to the interior. This alternative design protects the HXs from external hazards such as wind, tornado, and aircraft crash. The proposed design integrates the VV HXs into a VV pressure suppression system (VVPSS) tank that contains water to condense vapour in case of a leak into the plasma chamber. The proposal is to also use this water as the ultimate sink when removing decay heat from the VV system. The RELAP5-3D model has been run under normal operating and abnormal (decay heat) conditions. Results indicate that this alternative design is feasible, with no effects on the VVPSS tank under normal operation and with tank temperature and pressure increasing under decay heat conditions resulting in a requirement to remove steam generated if the VVPSS tank low pressure must be maintained.

Carbajo, Juan J [ORNL; Yoder Jr, Graydon L [ORNL; Dell'Orco, Giovanni [ITER Organization, Saint Paul Lez Durance, France; Curd, Warren [ITER Organization, Saint Paul Lez Durance, France; Kim, Seokho H [ORNL

2010-01-01

180

GPU computing with Kaczmarz's and other iterative algorithms for linear systems.  

PubMed

The graphics processing unit (GPU) is used to solve large linear systems derived from partial differential equations. The differential equations studied are strongly convection-dominated, of various sizes, and common to many fields, including computational fluid dynamics, heat transfer, and structural mechanics. The paper presents comparisons between GPU and CPU implementations of several well-known iterative methods, including Kaczmarz's, Cimmino's, component averaging, conjugate gradient normal residual (CGNR), symmetric successive overrelaxation-preconditioned conjugate gradient, and conjugate-gradient-accelerated component-averaged row projections (CARP-CG). Computations are preformed with dense as well as general banded systems. The results demonstrate that our GPU implementation outperforms CPU implementations of these algorithms, as well as previously studied parallel implementations on Linux clusters and shared memory systems. While the CGNR method had begun to fall out of favor for solving such problems, for the problems studied in this paper, the CGNR method implemented on the GPU performed better than the other methods, including a cluster implementation of the CARP-CG method. PMID:20526446

Elble, Joseph M; Sahinidis, Nikolaos V; Vouzis, Panagiotis

2010-06-01

181

Wall conditioning on ITER  

NASA Astrophysics Data System (ADS)

Like all tokamaks, ITER will require wall conditioning systems and strategies for successful operation from the point of view of plasma-facing surface preparation. Unlike today's devices however, ITER will have to manage large quantities of tritium fuel, imposing on wall conditioning a major responsibility for tritium inventory control. It will also feature the largest plasma-facing beryllium surface ever used in a tokamak and its high duty cycle and long pulse are expected to lead to the rapid formation of deposited layers in which tritium can accumulate. This paper summarises the currently planned ITER wall conditioning systems and describes the strategy for their use throughout exploitation of the device.

Shimada, Michiya; Pitts, Richard A.

2011-08-01

182

Iterative absolute electroanalytical approach to characterization of bulk redox conducting systems.  

PubMed

A novel electroanalytical approach is proposed here, and it is demonstrated with the direct and simultaneous determination of two unknowns: the concentration of redox sites and the apparent diffusion coefficient for charge propagation in a single crystal of dodecatungstophosphoric acid. This Keggin-type polyoxometalate serves as a model bulk redox conducting inorganic material for solid-state voltammetry. The system has been investigated using an ultramicrodisk working electrode in the absence of external liquid supporting electrolyte. The analytical method requires numerical solution of the combination of two equations in which the first one describes current (or charge) in a well-defined (either spherical or linear) diffusional regime and the second general equation describes chronoamperometric (or normal pulse voltammetric current) under mixed (linear-spherical) conditions. The iterative approach is based on successive approximations through calculation and minimizing the least-squares error function. The method is fairly universal, and in principle, it can be extended to the investigation of other bulk systems including sol-gel processed materials, redox melts, and solutions on condition that they are electroactive and well behaved, they contain redox centers at sufficiently high level, and a number of electrons for the redox reaction considered is known. PMID:15144177

Lewera, Adam; Miecznikowski, Krzysztof; Chojak, Malgorzata; Makowski, Oktawian; Golimowski, Jerzy; Kulesza, Pawel J

2004-05-15

183

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

NASA Astrophysics Data System (ADS)

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

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

2005-09-01

184

Wide-angle ITER-prototype tangential infrared and visible viewing system for DIII-Da)  

NASA Astrophysics Data System (ADS)

An imaging system with a wide-angle tangential view of the full poloidal cross-section of the tokamak in simultaneous infrared and visible light has been installed on DIII-D. The optical train includes three polished stainless steel mirrors in vacuum, which view the tokamak through an aperture in the first mirror, similar to the design concept proposed for ITER. A dichroic beam splitter outside the vacuum separates visible and infrared (IR) light. Spatial calibration is accomplished by warping a CAD-rendered image to align with landmarks in a data image. The IR camera provides scrape-off layer heat flux profile deposition features in diverted and inner-wall-limited plasmas, such as heat flux reduction in pumped radiative divertor shots. Demonstration of the system to date includes observation of fast-ion losses to the outer wall during neutral beam injection, and shows reduced peak wall heat loading with disruption mitigation by injection of a massive gas puff.

Lasnier, C. J.; Allen, S. L.; Ellis, R. E.; Fenstermacher, M. E.; McLean, A. G.; Meyer, W. H.; Morris, K.; Seppala, L. G.; Crabtree, K.; Van Zeeland, M. A.

2014-11-01

185

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

186

The strengths, needs and possible drawbacks of different heating and current drive systems in relation to ITER  

NASA Astrophysics Data System (ADS)

The final success of the ITER project will be determined decisively by the appropriate combination of plasma heating and current drive systems to be chosen in the near future. Motivated by the remarkable progress in the heating area, but also in view of still existing major issues with respect to the requirements of ITER, this paper tries to give a fair assessment of the status and perspectives of the four H&CD systems presently under discussion: electron cyclotron waves (ECW), ion cyclotron waves (ICW), lower hybrid waves (LH) and neutral beam injection (NBI). Following a pertaining analysis of an EU ad hoc group it can be concluded that all systems, in spite of the remarkable achievements at the various fusion experiments, will not meet all ITER requirements and need further development and investigations in all four cases. Particular needs or even severe problems arise from both the more stringent technical constraints (e.g. reduced area available for H&CD installation, larger plasma distance of H&CD components, radiological implications, etc) and the increasing need to also explore steady-state operation eventually in `advanced scenarios' in ITER. Resulting H&CD issues or problems will be addressed, such as not sufficiently qualified RF sources, problems in connection with the plasma-facing RF-coupling structures, or the still unsatisfactory status of negative ion technology in the case of NBI. Stationary current drive (with prescribed radial profile and at acceptable efficiency) and the related various control functions seem the greatest challenge for `advanced' ITER operation and further steps beyond it.

Wilhelm, R.

1998-08-01

187

Synthesis of trigeneration systems: sensitivity analyses and resilience.  

PubMed

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

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

2013-01-01

188

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

189

Reproducible analyses of microbial food for advanced life support systems.  

PubMed

The use of yeasts in Controlled Ecological Life Support Systems (CELSS) for microbial food regeneration in space required the accurate and reproducible analysis of intracellular carbohydrate and protein levels. The reproducible analysis of glycogen was a key element in estimating overall content of edibles in candidate yeast strains. Typical analytical methods for estimating glycogen in Saccharomyces were not found to be entirely applicable to other candidate strains. Rigorous cell lysis coupled with acid/base fractionation followed by specific enzymatic glycogen analyses were required to obtain accurate results in two strains of Candida. A profile of edible fractions of these strains was then determined. The suitability of yeasts as food sources in CELSS food production processes is discussed. PMID:11541295

Petersen, G R

1988-10-01

190

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

SciTech Connect

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

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

2011-01-01

191

An Illumination Modeling System for Human Factors Analyses  

NASA Technical Reports Server (NTRS)

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

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

2002-01-01

192

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

Microsoft Academic Search

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

Norman E. Groner

2008-01-01

193

Task-Space Iterative Learning for Redundant Robotic Systems: Existence of a Task-Space Control and Convergence of Learning  

NASA Astrophysics Data System (ADS)

This paper presents a feasibility study of iterative learning control for a class of redundant multi-joint robotic systems when a desired motion trajectory is specified in task-space with less dimension than that of joint space. First, it is shown that if the desired trajectory described in task-space for a time interval t ? [0,T] is twice continuously differentiable then a unique control signal describable in task-space exists despite of the system joint-redundancy. Second, a learning control update law is constructed through transpose of the Jacobian matrix of task-space coordinates with respect to joint coordinates by using measured data of motion trajectories in task-space. Third, the convergence of trajectory trackings through iterative learning is proved theoretically on the basis of original nonlinear robot dynamics in joint space.

Arimoto, Suguru; Sekimoto, Masahiro; Kawamura, Sadao

194

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

2012-05-01

195

Use of the iterative diagnosis and design approach in the development of suitable agroforestry systems for a target area  

Microsoft Academic Search

The process of iterative diagnosis and design with the active participation of farmers and extension agents was found effective\\u000a in identifying appropriate agroforestry systems for farmers in the Bugesera and Gisaka-Migongo (BGM) regions of Rwanda. Periodic\\u000a re-evaluation of research assumptions and technology designs was based on feedback from farmers and extentionists through\\u000a regular visits to station trials, early initiation of

E. Pinners; V. Balasubramanian

1991-01-01

196

Waveform-Relaxation based iterative real-time playback schemes for testing of wide area power system controllers  

Microsoft Academic Search

An alternative to real-time simulation for hardware-in-the-loop testing is proposed. This involves system simulation, not necessarily done in real time, and real-time playback of the simulated output to the controller under test. The time-stamped controller output is stored and subsequently fed as an input to the simulation. This whole process is done iteratively as in the Waveform Relaxation method, till

A. M. Kulkarni; K. Salunkhe; M. C. Chandorkar; S. P. Panda; N. Sankaranarayanan

2010-01-01

197

Leveraging Anderson Acceleration for improved convergence of iterative solutions to transport systems  

NASA Astrophysics Data System (ADS)

In this note we demonstrate that using Anderson Acceleration (AA) in place of a standard Picard iteration can not only increase the convergence rate but also make the iteration more robust for two transport applications. We also compare the convergence acceleration provided by AA to that provided by moment-based acceleration methods. Additionally, we demonstrate that those two acceleration methods can be used together in a nested fashion. We begin by describing the AA algorithm. At this point, we will describe two application problems, one from neutronics and one from plasma physics, on which we will apply AA. We provide computational results which highlight the benefits of using AA, namely that we can compute solutions using fewer function evaluations, larger time-steps, and achieve a more robust iteration.

Willert, Jeffrey; Taitano, William T.; Knoll, Dana

2014-09-01

198

Comparative Genomic Analyses of the Bacterial Phosphotransferase System  

PubMed Central

We report analyses of 202 fully sequenced genomes for homologues of known protein constituents of the bacterial phosphoenolpyruvate-dependent phosphotransferase system (PTS). These included 174 bacterial, 19 archaeal, and 9 eukaryotic genomes. Homologues of PTS proteins were not identified in archaea or eukaryotes, showing that the horizontal transfer of genes encoding PTS proteins has not occurred between the three domains of life. Of the 174 bacterial genomes (136 bacterial species) analyzed, 30 diverse species have no PTS homologues, and 29 species have cytoplasmic PTS phosphoryl transfer protein homologues but lack recognizable PTS permeases. These soluble homologues presumably function in regulation. The remaining 77 species possess all PTS proteins required for the transport and phosphorylation of at least one sugar via the PTS. Up to 3.2% of the genes in a bacterium encode PTS proteins. These homologues were analyzed for family association, range of protein types, domain organization, and organismal distribution. Different strains of a single bacterial species often possess strikingly different complements of PTS proteins. Types of PTS protein domain fusions were analyzed, showing that certain types of domain fusions are common, while others are rare or prohibited. Select PTS proteins were analyzed from different phylogenetic standpoints, showing that PTS protein phylogeny often differs from organismal phylogeny. The results document the frequent gain and loss of PTS protein-encoding genes and suggest that the lateral transfer of these genes within the bacterial domain has played an important role in bacterial evolution. Our studies provide insight into the development of complex multicomponent enzyme systems and lead to predictions regarding the types of protein-protein interactions that promote efficient PTS-mediated phosphoryl transfer. PMID:16339738

Barabote, Ravi D.; Saier, Milton H.

2005-01-01

199

Please cite this article in press as: A. Martin, et al., ITER blanket manifold system: Integration, assembly and maintenance, Fusion Eng. Des. (2014), http://dx.doi.org/10.1016/j.fusengdes.2014.04.013  

E-print Network

Please cite this article in press as: A. Martin, et al., ITER blanket manifold system: Integration.elsevier.com/locate/fusengdes ITER blanket manifold system: Integration, assembly and maintenance Alex Martina, , George Dellopoulosb. Tel.: +33 615 36 40 74; fax: +33 4 42 17 60 36. E-mail address: alex.martin@iter.org (A. Martin). 2

Raffray, A. René

200

All-electron KKR Calculations for Metallic Systems with Thousands of Atoms Per Cell via Sparse Matrix Iterative Solvers  

NASA Astrophysics Data System (ADS)

To perform electronic-structure calculations for inherently large systems, such as a quantum dots or interfaces like domain walls, we must perform the calculations over very large unit cells (10^4 to 10^8 atoms). For the inverse Green's function G-1, KKR methods typically solve for G by direct inversion. Using a screened, k-space hybrid KKR, we solve Dyson's equation for the Green's function using a reference state via G = Gref [ I - (t - tref) Gref]-1, scattering matrices t and tref are known and the non-Hermitian tensor Gref is chosen for convenience and sparsity [1]. The approach is O(N) for bandgap materials, whereas it is O(N^2) for metals but with a potentially large prefactor. Based upon Sparse Approximate Inverse (or SPAI) technique [2], we generalize the algorithm for complex, non-Hermitian matrices, then use the method as a preconditioner for the inversion to reduce the iteration counts (hence, reduce the prefactor) of the iterative Krylov-space inverses, such as TFQMR, to address large-scale metallic systems. Parallel iterative and energy contour solves are made also. We explore the numerical efficiency and scaling versus atoms per unit cells. [1] Smirnov and Johnson, Comp. Phys. Comm. 148, 74-80 (2002). [2] Grote and Huckle, SIAM J. Sci. Comput. 18, 8

Khan, Suffian; Alam, Aftab; Johnson, Duane

2009-03-01

201

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

202

Templates for the Solution of Linear Systems: Building Blocks for Iterative Methods1  

E-print Network

in Postscript from over the Internet. To retrieve the postscript le you can use one of the following methods: 1. anonymous ftp to www.netlib.org cd templates get templates.ps quit 2. from any machine on the Internet type computational problems facing researchers. Chapter 3 focuses on preconditioners. Many iterative methods depend

Hammett, Greg

203

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

E-print Network

and practice. In particular, low-density parity-check (LDPC) codes, introduced by Gallager in the 1960s, are the class of codes at the heart of iterative coding. Since these codes are quite general and exhibit good performance under message-passing decoding...

Wang, Chia-Wen

2008-10-10

204

On The Problem Of In-vessel Mirrors For Diagnostic Systems Of ITER  

SciTech Connect

The present status of the investigations with ITER-candidate mirror materials and directed on solution of the in-vessel mirror problem, are presented in the paper. The current tasks in the R and D of diagnostic mirrors and outstanding questions are discussed.

Voitsenya, V. S. [IPP, NSC Kharkov Institute of Physics and Technology, Kharkov 61108 (Ukraine); Litnovsky, A. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich, Ass. EURATOM- FZ Juelich, D-52425 Juelich (Germany)

2008-03-12

205

Extension of Reference Signals in Iterative Learning Control for Non-Minimum Phase Systems  

NASA Astrophysics Data System (ADS)

This paper proposes to extend given reference signals in the iterative learning control context so that the resultant signals have the same right half plane zero structure as the given plants. This extension enables preventing control inputs exponentially increasing. The extending signals can be synthesized by solving a linear equation. The effectiveness of the proposed method is examined by a numerical example.

Ooi, Chee Leong; Asai, Toru; Okajima, Hiroshi

206

A Design of Discrete-Time Iterative Learning Control Systems for SISO Plants  

NASA Astrophysics Data System (ADS)

In this paper, it will be modified an iterative learning control algorithm proposed by Owens and Feng, which guarantees the monotonic convergence of the tracking error norms along with the trial. The learning gain of the proposed method is determined through a quadratic cost function. Numerical simulations will be presented to confirm the validity of the proposed design.

Kase, Wataru

207

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

208

Description of Transmutation Library for Fuel Cycle System Analyses  

SciTech Connect

This report documents the Transmutation Library that is used in Fuel Cycle System Analyses. This version replaces the 2008 version.[Piet2008] The Transmutation Library has the following objectives: • Assemble past and future transmutation cases for system analyses. • For each case, assemble descriptive information such as where the case was documented, the purpose of the calculation, the codes used, source of feed material, transmutation parameters, and the name of files that contain raw or source data. • Group chemical elements so that masses in separation and waste processes as calculated in dynamic simulations or spreadsheets reflect current thinking of those processes. For example, the CsSr waste form option actually includes all Group 1A and 2A elements. • Provide mass fractions at input (charge) and output (discharge) for each case. • Eliminate the need for either “fission product other” or “actinide other” while conserving mass. Assessments of waste and separation cannot use “fission product other” or “actinide other” as their chemical behavior is undefined. • Catalog other isotope-specific information in one place, e.g., heat and dose conversion factors for individual isotopes. • Describe the correlations for how input and output compositions change as a function of UOX burnup (for LWR UOX fuel) or fast reactor (FR) transuranic (TRU) conversion ratio (CR) for either FR-metal or FR-oxide. This document therefore includes the following sections: • Explanation of the data set information, i.e., the data that describes each case. In no case are all of the data presented in the Library included in previous documents. In assembling the Library, we return to raw data files to extract the case and isotopic data, into the specified format. • Explanation of which isotopes and elements are tracked. For example, the transition metals are tracked via the following: two Zr isotopes, Zr-other, Tc99, Tc-other, two Mo-Ru-Rh-Pd isotopes, Mo-Ru-Rh-Pd-other, four other specific TM isotopes, and TM-other. Mo-Ru-Rh-Pd are separated because their content constrains the loading of waste in glass, so we have to know the mass of those elements independent of others. • Rules for collapsing long lists of isotopes (~1000) to the 81 items in the library. For each tracked isotope, we define which short-lived isotopes’ mass (at t=0) is included with the mass of the tracked isotope at t=0, which short-lived radioactive progeny must be accounted for when the tracked isotope decays, and to which of the other 80 items the mass of the tracked isotope goes when it decays. • Explanation of where raw data files can be found on the fuel cycle data portal. • Explanation of generic cross section sets • Explanation of isotope-specific parameters such as heat and dose conversion factors • Explanation of the LWR UOX burnup and FR TRU CR correlations.

Steven J. Piet; Samuel E. Bays; Edward A. Hoffman

2010-08-01

209

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

NASA Technical Reports Server (NTRS)

This paper describes a Strategic Environmental Research and Development Program (SERDP) funded project led jointly by the Marine Corps Multi-Commodity Maintenance Centers, and the Air and Energy Engineering Research Laboratory (AEERL) of the USEPA. The research focuses on paint booth exhaust minimization using recirculation, and on volatile organic compound (VOC) oxidation by the modules of a hybrid air pollution control system. The research team is applying bench, pilot and full scale systems to accomplish the goals of reduced cost and improved effectiveness of air treatment systems for paint booth exhaust.

Watt, Lewis C.; Cannon, Fred S.; Heinsohn, Robert J.; Spaeder, Timothy A.

1995-01-01

210

Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Least Squares Policy Iteration  

E-print Network

Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Least Squares Policy Iteration Bias-Variance Trade-o in Control Problems Christophe Thiéry and Bruno Scherrer/27 #12; Policy Iteration / Optimistic Policy Iteration Least-Squares Policy Iteration Experiments Markov

Scherrer, Bruno

211

Experimental neutronics tests for a neutron activation system for the European ITER TBM  

NASA Astrophysics Data System (ADS)

We are investigating methods for neutron flux measurement in the ITER TBM. In particular we have tested sets of activation materials leading to induced gamma activities with short half-lives of the order of tens of seconds up to minutes and standard activation materials. Packages of activation foils have been irradiated with the intense neutron generator of Technical University of Dresden in a pure DT neutron field as well as in a neutronics mock-up of the European ITER HCLL TBM. An important aim was to check whether the gamma activity induced in the activation foils in these packages could be measured simultaneously. It was indeed possible to identify gamma lines of interest in gamma-ray measurements immediately after extraction from the irradiation.

Klix, A.; Fischer, U.; Gehre, D.; Kleizer, G.; Raj, P.; Rovni, I.; Ruecker, Tom

2014-08-01

212

Iterative solvers within sequences of large linear systems in non-linear structural mechanics  

Microsoft Academic Search

MSC (2000) 04A25 This article treats the computation of discretized constitutive models of evolutio nary-type (like models of viscoelasticity, plasticity and viscoplasticity) with quasi-static finite elements using diagonally implic it Runge-Kutta methods (DIRK) combined with the Multilevel-Newton algorithm (MLNA). The main emphasis is on promoting iterative methods, as op- posed to the more traditional direct methods, for solving the non-symmetric

Stefan Hartmann; Jurjen Duintjer Tebbens; Karsten J. Quint; Andreas Meister

2009-01-01

213

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

Microsoft Academic Search

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

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

2000-01-01

214

Forced sequence sequential decoding: a concatenated coding system with iterated sequential inner decoding  

Microsoft Academic Search

We describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1\\/4 and memory M=23, and block interleaved outer Reed-Solomon (RS) codes with nonuniform profile. With this scheme decoding with good performance is possible as low as Eb\\/N0=0.6 dB, which is about 1.25 dB below the signal-to-noise ratio (SNR) that marks the

Ole Riis Jensen; Erik Paaske

1998-01-01

215

Electric ship power system integration analyses through modeling and simulation  

Microsoft Academic Search

The Center for Electromechanics (CEM) at the University of Texas is engaged in the development of a comprehensive power system model in order to address several challenging issues facing the development of a viable and effective integrated power system architecture for future naval platforms. The power system under consideration reflects the notional DD power system architecture and is developed in

A. Ouroua; L. Domaschk; J. H. Beno

2005-01-01

216

Controlling ITER Scenarios  

NASA Astrophysics Data System (ADS)

The three principal ITER operational scenarios are the 15 MA, 5.3 T, Q=10 inductive scenario, the 1000 s, 10.5-13.5 MA, 5.3 T, Q>5 Hybrid scenario, and the 3000 s, 7.5-10 MA, 5.3 T, Q˜5 steady-state scenario. Extensive modeling of the inductive scenario indicates that the ITER baseline actuators should be capable of all of the required basic control and that the ITER diagnostic specifications should provide adequate measurements with which to carry out such control. Current ramp-up times as short as 50 s and ramp-down times as low as 60 s are within control limits. Expected plasma disturbances can also be controlled. More advanced control is required for the hybrid and steady-state scenarios. Depending on transport assumptions, some modeling indicates that the baseline actuators should also be capable of achieving the ITER performance goals in the hybrid scenario with modest confinement improvement (H98˜1.2). For steady-state scenarios, it is likely that substantial upgrades to the heating and current drive systems will be required to achieve the high performance and pulse length goals. High confinement (H98<=1.7) is also required to achieve these performance goals, challenging stability limits and requiring simultaneous control of multiple instabilities (e.g., ELMs, NTMs, RWMs) with limited shared actuators. The ITER Plasma Control System is being developed taking into account these challenging control requirements.

Snipes, J. A.; Campbell, D. J.; Casper, T.; Gribov, Y.; Kim, S.-H.; Winter, A.

2011-11-01

217

Spaceborne power systems preference analyses. Volume 2: Decision analysis  

NASA Technical Reports Server (NTRS)

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

218

Analyses of power system vulnerability and total transfer capability  

E-print Network

companies and the ISOs. An uninterrupted and high quality power is required for the sustainable development of a technological society. Power system blackouts generally result from cascading outages. Protection system hidden failures remain dormant when...

Yu, Xingbin

2006-04-12

219

Status of transmission line and matching network design and testing for the ITER ion cyclotron heating and current drive system  

NASA Astrophysics Data System (ADS)

The ITER Ion Cyclotron Heating and Current Drive System is required to deliver 20 MW of RF Power in the frequency range 40-55 MHz to ITER plasmas for pulse lengths up to 3600 s. Components used in the transmission line and matching system include 305 mm diameter, Z0 = 50 ? components with gas cooled inner conductors, and 330 mm diameter, Z0 = 20 ? components with water-cooled inner conductors. All operate at pulse lengths up to 3600 s. Components used include transmission line sections, gas barriers, hybrid power splitters, stubs, hybrid phase shifters, coaxial 4-port switches, and vacuum capacitors. The system uses pre-matching near the antenna and a matching network ˜20 m away, including decouplers that compensate for the mutual inductance between antenna array elements. Some 50 ? component test articles have been fabricated and will be shown. High power RF test fixtures have been constructed including a resonant ring that produces 6 MW of circulating power with 340 kW input power and VSWR as low as 1.15. It has been used to investigate the dependence of inner conductor temperature on gas velocity at power levels up to ˜6 MW for pulse lengths up to 1 hour.

Goulding, R. H.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Campbell, I. H.; Fredd, E.; Gray, S. L.; Greenough, N.; Moon, R. L.; Pesavento, P. V.; Peters, R. B.; Sanabria, R. M.; Sparks, D. O.; Wolframe, W. J.

2014-02-01

220

Microwave power transmission system studies. Volume 2: Introduction, organization, environmental and spaceborne systems analyses  

NASA Technical Reports Server (NTRS)

Introduction, organization, analyses, conclusions, and recommendations for each of the spaceborne subsystems are presented. Environmental effects - propagation analyses are presented with appendices covering radio wave diffraction by random ionospheric irregularities, self-focusing plasma instabilities and ohmic heating of the D-region. Analyses of dc to rf conversion subsystems and system considerations for both the amplitron and the klystron are included with appendices for the klystron covering cavity circuit calculations, output power of the solenoid-focused klystron, thermal control system, and confined flow focusing of a relativistic beam. The photovoltaic power source characteristics are discussed as they apply to interfacing with the power distribution flow paths, magnetic field interaction, dc to rf converter protection, power distribution including estimates for the power budget, weights, and costs. Analyses for the transmitting antenna consider the aperture illumination and size, with associated efficiencies and ground power distributions. Analyses of subarray types and dimensions, attitude error, flatness, phase error, subarray layout, frequency tolerance, attenuation, waveguide dimensional tolerances, mechanical including thermal considerations are included. Implications associated with transportation, assembly and packaging, attitude control and alignment are discussed. The phase front control subsystem, including both ground based pilot signal driven adaptive and ground command approaches with their associated phase errors, are analyzed.

Maynard, O. E.; Brown, W. C.; Edwards, A.; Haley, J. T.; Meltz, G.; Howell, J. M.; Nathan, A.

1975-01-01

221

Coordinate uncertainty analyses of coupled multiple measurement systems  

NASA Astrophysics Data System (ADS)

Precision three-dimensional measurement of large-scale workpiece frequently involves the combination of several different types of measurement systems; they may be laser tracker, total station, laser scanner and portable coordinate measuring machines, etc. In order to provide optimization measuring results, a new method, called the isolated variable sub-system (IVSS), has been developed to deal with variable coupling that fully takes into account the uncertainty of each measurement individual system. The IVSS method is a combination of pattern search and singular value decomposition. It can effectively determine the optimized location and orientation of each measurement system and minimizes the coordinate combined uncertainty by multivariate statistics to the measured data. Intensive experimental studies have been made to check the validity of the proposed method; the results show that using this technology the measuring accuracy of coupled multiple measurement systems can be improved by about 49% and can accommodate missing data points from some of the measurement systems.

Liu, Wanli; Wang, Zhankui

2010-06-01

222

Spaceborne power systems preference analyses. Volume 1: Summary  

NASA Technical Reports Server (NTRS)

Sixteen alternative spaceborne nuclear power system concepts were ranked using multiattribute decision analysis to identify promising concepts for further technology development. Four groups interviewed were: safety, systems definition and design, technology assessment, and mission analysis. The ranking results were consistent from group and for different utility function models for individuals.

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

1985-01-01

223

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

224

Wavelet Based Iterative Learning Control with Fuzzy PD Feedback for Position Tracking of A Pneumatic Servo System  

E-print Network

In this paper, a wavelet-based iterative learning control (WILC) scheme with Fuzzy PD feedback is presented for a pneumatic control system with nonsmooth nonlinearities and uncertain parameters. The wavelet transform is employed to extract the learnable dynamics from measured output signal before it can be used to update the control profile. The wavelet transform is adopted to decompose the original signal into many low-resolution signals that contain the learnable and unlearnable parts. The desired control profile is then compared with the learnable part of the transformed signal. Thus, the effects from unlearnable dynamics on the controlled system can be attenuated by a Fuzzy PD feedback controller. As for the rules of Fuzzy PD controller in the feedback loop, a genetic algorithm (GA) is employed to search for the inference rules of optimization. A proportional-valve controlled pneumatic cylinder actuator system is used as the control target for simulation. Simulation results have shown a much-improved posi...

Huang, C E

2008-01-01

225

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

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

226

Cost Analyses of Fuel Cell Stacks/Systems  

E-print Network

to be viable in the market place, they must have attractive performance and cost attributes. System · clean hydrocarbon or alcohol based fuel · 30 second start-up · satisfies emissions standards 45

227

Analyses Of Transient Events In Complex Valve and Feed Systems  

NASA Technical Reports Server (NTRS)

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

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

2005-01-01

228

Democratizing Systems Immunology with Modular Transcriptional Repertoires Analyses  

PubMed Central

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

Chaussabel, Damien; Baldwin, Nicole

2014-01-01

229

Waveform and location analyses of localised lightning locating system  

Microsoft Academic Search

Lightning mapping or locating systems are based on several working principles such as the Time of Arrival (ToA) and the Directional Finder (DF). The country wide lightning locating system (LLS) owned by TNB Malaysia is able to determine the coordinate of the cloud-to-ground lightning strike within 500m accuracy. A new method is proposed to determine the coordinate of any cloud-to-ground

Zulkurnain Abdul-Malek; Z. Adzis; Aulia; Novizon; N. Abdullah

2010-01-01

230

A Framework for Integrated Component and System Analyses of Instabilities  

NASA Technical Reports Server (NTRS)

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

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

2010-01-01

231

Quantitative analyses of complement fixation in three immune complex systems.  

PubMed Central

The quantitative interaction of three different immune complex systems with complement has been investigated. dsDNA/anti-DNA, heat-aggregated IgG subfractions, and human IgG/rabbit anti-human IgG complexes were tested for their ability to consume complement (immune haemolysis assay) and to bind to red blood cells in a complement-mediated reaction (the RBC-CF assay). Our results indicate that some physical and immunological properties of the dsDNA/anti-DNA immune complex systems are significantly different from those of immune complexes that involve more common globular protein antigens. This difference in properties may help explain the role of dsDNA/anti-DNA immune complexes in systemic lupus erythematosus pathogenesis. PMID:6611301

Horgan, C; Taylor, R P

1984-01-01

232

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

NASA Astrophysics Data System (ADS)

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

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

2014-07-01

233

Mechanical Analyses for coupled Vegetation-Flow System  

NASA Astrophysics Data System (ADS)

Vegetation in riparian areas plays important roles in hydrology, geomorphology and ecology in local environment. Mechanical response of the aquatic vegetation to hydraulic forces and its impact on flow hydraulics have received considerable attention due to implications for flood control, habitat restoration, and water resources management. This study aims to advance understanding of the mechanical properties of in-stream vegetation including drag force, moment and stress. Dynamic changes of these properties under various flow conditions largely determine vegetation affected flow field and dynamic resistance with progressive bending, and hydraulic conditions for vegetation failure (rupture or wash-out) thus are critical for understanding the coupled vegetation-flow system. A new approach combining fluid and material mechanics is developed in this study to examine the behavior of both rigid and flexible vegetation. The major advantage of this approach is its capability to treat large deflection (bending) of plants and associated changes of mechanical properties in both vegetation and flow. Starting from simple emergent vegetation, both static and dynamic formulations of the problem are presented and the solutions are compared. Results show the dynamic behavior of a simplified system mimicking complex and real systems, implying the approach is able to disclose the physical essence of the coupled system. The approach is extended to complex vegetation under both submerged and emergent conditions using more realistic representation of biomechanical properties for vegetation.

Chen, L.; Acharya, K.; Stone, M.

2010-12-01

234

Advanced Program Analyses for Object-oriented Systems  

E-print Network

PROLANGS · Languages/Compilers and Software Engineering ­ Algorithm design and prototyping · Mature research projects ­ Change impact analysis for object-oriented systems PASTE'01, DCS-TR-533(9/03), OOPSLA'04, ICSM'05, FSE'06, IEEE-TSE 2007, ISSTA'07 ­ Robustness testing of Java web server applications

Ryder, Barbara G.

235

BNL Pulsed Magnet Magnet System Cooldown and Structural Analyses  

E-print Network

in the epoxy/glass insulation. Half lapps of kapton and fiberglass, similar to the CS model coil will retain - Choose Insulation Systems. Determine where Kapton is used. · Stress Analysis, Assess Radial load of thumb for He breakdown voltage (1 volt/mil at 1 atmosphere) for the insulation thickness proposed

McDonald, Kirk

236

Analysing Student Programs in the PHP Intelligent Tutoring System  

ERIC Educational Resources Information Center

Programming is a subject that many beginning students find difficult. The PHP Intelligent Tutoring System (PHP ITS) has been designed with the aim of making it easier for novices to learn the PHP language in order to develop dynamic web pages. Programming requires practice. This makes it necessary to include practical exercises in any ITS that…

Weragama, Dinesha; Reye, Jim

2014-01-01

237

System analyses on advanced nuclear fuel cycle and waste management  

Microsoft Academic Search

To evaluate the impacts of accelerator-driven transmutation of waste (ATW) fuel cycle on a geological repository, two mathematical models are developed: a reactor system analysis model and a high-level waste (HLW) conditioning model. With the former, fission products and residual trans-uranium (TRU) contained in HLW generated from a reference ATW plant operations are quantified and the reduction of TRU inventory

Myeongguk Cheon

2005-01-01

238

Asynchronous Modified Policy Iteration with Singlesided Updates  

E-print Network

Markovian decision processes (MDPs) can be reduced to the problem of solving a finite system of non classical iterative dynamic programming (DP) methods for solving the Bellman equation: policy iteration appropriate to think of these two classical methods as two extremes of a continuum of iterative methods

Baveja, Satinder Singh

239

A Novel Infinite-Time Optimal Tracking Control Scheme for a Class of Discrete-Time Nonlinear Systems via the Greedy HDP Iteration Algorithm  

Microsoft Academic Search

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

Huaguang Zhang; Qinglai Wei; Yanhong Luo

2008-01-01

240

A novel design strategy for iterative learning and repetitive controllers of systems with a high modal density: Theoretical background  

NASA Astrophysics Data System (ADS)

This paper discusses the design and application of iterative learning control (ILC) and repetitive control (RC) for high modal density systems. Typical examples of these systems are structural and acoustical systems considered in active structural acoustic control (ASAC) and active noise control (ANC) applications. The application of traditional ILC and RC design techniques, which are based on a parametric system model, on systems with a high modal density has several important drawbacks: the design procedure is complex, the controllers require much computational power and the robustness of the controllers is low. This paper describes a novel strategy to design noncausal ILC and RC filters, which is especially suited for high modal density systems. Since it does not require a parametric system model, the novel strategy avoids several drawbacks of the traditional techniques: no cumbersome parametric model estimation is required; the ILC and RC controllers are robust to small changes of the poles and zeros of the controlled system; and the complexity of the ILC and RC control filters is restricted. A crucial element in the proposed strategy is the noncausal filtering in the ILC and RC controllers, which requires the availability of a trigger signal to announce a new ILC trial or RC period in advance. A numerical validation on a simulation model proves the potential of the developed strategy.

Pinte, G.; Stallaert, B.; Sas, P.; Desmet, W.; Swevers, J.

2010-02-01

241

Performance Evaluation of LDPC Coding and Iterative Decoding System in BPM R/W Channel Affected by Head Field Gradient, Media SFD and Demagnetization Field  

NASA Astrophysics Data System (ADS)

We evaluate the performance of the write-margin for the low-density parity-check (LDPC) coding and iterative decoding system in the bit-patterned media (BPM) R/W channel affected by the write-head field gradient, the media switching field distribution (SFD), the demagnetization field from adjacent islands and the island position deviation. It is clarified that the LDPC coding and iterative decoding system in R/W channel using BPM at 3 Tbit/inch2 has a write-margin of about 20%.

Nakamura, Yasuaki; Okamoto, Yoshihiro; Osawa, Hisashi; Aoi, Hajime; Muraoka, Hiroaki

242

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 management…

Treuthardt, Leena; Valimaa, Jussi

2008-01-01

243

How far away is infinity? Using asymptotic analyses in multiple-antenna systems  

Microsoft Academic Search

Asymptotic theorems are very commonly used in probability. For systems whose performance depends on a set of random variables, asymptotic analyses are often used to simplify calculations and obtain results yielding useful hints at the behavior of the system when the parameters take on finite values. These asymptotic analyses are especially useful whenever the convergence to the asymptotic results is

E. Biglieri; Giorgio Taricco; Aiitonia Tulino

2002-01-01

244

Sensitivity analyses of cables to suspen-dome structural system.  

PubMed

The construction of the cables is a key step for erecting suspen-dome structures. In practical engineering, it is difficult to ensure that the designed pre-stresses of cables have been exactly introduced into the structures in the site; so it is necessary to evaluate the influence of the variation of the pre-stresses on the structural behavior. In the present work, an orthogonal design method was employed to investigate the pre-stressed cables' sensitivity to the suspen-dome system. The investigation was concentrated on a Kiewitt suspen-dome. Parametric studies were carried out to study the sensitivity of the structure's static behavior, dynamic behavior, and buckling loads when the pre-stresses in the cables varied. The investigation indicated that suspen-dome structures are sensitive to the pre-stresses in all cables; and that the sensitivity depended on the location of the cables and the kind of structural behavior. Useful suggestions are given at the end of the paper. PMID:15322998

Gao, Bo-qing; Weng, En-hao

2004-09-01

245

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

SciTech Connect

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

Miller, Gregory H.

2003-08-06

246

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

E-print Network

control approaches were proposed for: linear or nonlinear systems, time delay systems, cascade systems in a fixed finite interval. In the networked control systems (NCS), because of the existence of time delays delays is less than the magnitude of the fixed time interval of the learning system, previous cycle based

Marquez, Horacio J.

247

Iterative baseband correction of phase noise in OFDM systems for transmission over multi-path and AWGN channels  

Microsoft Academic Search

In this paper, we present a novel iterative approach for canceling the phase noise generated by imperfect local oscillators in Orthogonal Frequency Division Multiplexing receivers. After the cancellation of Common Phase Error (CPE), an iterative technique is introduced which estimates Inter- Carrier Interference (ICI) components in the frequency domain and cancels their contribution in the time domain. Simulations are conducted

F. Marx; J. Farah

2005-01-01

248

Neutron activation for ITER  

SciTech Connect

There are three primary goals for the Neutron Activation system for ITER: maintain a robust relative measure of fusion power with stability and high dynamic range (7 orders of magnitude); allow an absolute calibration of fusion power (energy); and provide a flexible and reliable system for materials testing. The nature of the activation technique is such that stability and high dynamic range can be intrinsic properties of the system. It has also been the technique that demonstrated (on JET and TFTR) the highest accuracy neutron measurements in DT operation. Since the gamma-ray detectors are not located on the tokamak and are therefore amenable to accurate characterization, and if material foils are placed very close to the ITER plasma with minimum scattering or attenuation, high overall accuracy in the fusion energy production (7--10%) should be achievable on ITER. In the paper, a conceptual design is presented. A system is shown to be capable of meeting these three goals, also detailed design issues remain to be solved.

Barnes, C.W. [Los Alamos National Lab., NM (United States); Loughlin, M.J. [JET Joint Undertaking, Abingdon (United Kingdom); Nishitani, Takeo [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

1996-04-29

249

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

250

Identification of multivariable nonlinear systems in the presence of colored noises using iterative hierarchical least squares algorithm.  

PubMed

This paper presents an efficient method for identification of nonlinear Multi-Input Multi-Output (MIMO) systems in the presence of colored noises. The method studies the multivariable nonlinear Hammerstein and Wiener models, in which, the nonlinear memory-less block is approximated based on arbitrary vector-based basis functions. The linear time-invariant (LTI) block is modeled by an autoregressive moving average with exogenous (ARMAX) model which can effectively describe the moving average noises as well as the autoregressive and the exogenous dynamics. According to the multivariable nature of the system, a pseudo-linear-in-the-parameter model is obtained which includes two different kinds of unknown parameters, a vector and a matrix. Therefore, the standard least squares algorithm cannot be applied directly. To overcome this problem, a Hierarchical Least Squares Iterative (HLSI) algorithm is used to simultaneously estimate the vector and the matrix of unknown parameters as well as the noises. The efficiency of the proposed identification approaches are investigated through three nonlinear MIMO case studies. PMID:24709386

Jafari, Masoumeh; Salimifard, Maryam; Dehghani, Maryam

2014-07-01

251

Automatic Extraction of Non-Iterated System Behavior from Verilog Specifications Lubomir Ivanov  

E-print Network

real-world systems and protocols such as the PCI bus protocol, the MESI cache coherence protocol, the T of a large, complex real- world system as a series-parallel poset with hundreds of thousands of elements can expression. Keywords: Series-parallel poset, formal verification, Verilog behavior extraction 1. INTRODUCTION

Ivanov, Lubomir

252

Signal detection for large MIMO systems using block-iterative generalized decision feedback equalizers (BI-GDFE)  

Microsoft Academic Search

This paper studies the problem of signal detection for generic MIMO channels with large signal dimensions. We propose a block-iterative generalized decision feedback equalization (BI-GDFE) receiver to recover the transmitted symbols in a block-iterative manner. By exploiting the input-decision correlation (IDC), a measure for the reliability of the earlier-made decisions, we design the feed-forward equalizers (FFEs) and feedback equalizers (FBEs)

Ying-Chang Liang; Sumei Sun; Chin Keong Ho

2005-01-01

253

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

Microsoft Academic Search

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

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

1990-01-01

254

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

Microsoft Academic Search

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

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

1990-01-01

255

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

256

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

257

All-electron KKR Calculations for Metallic Systems with Thousands of Atoms Per Cell via Sparse Matrix Iterative Solvers  

NASA Astrophysics Data System (ADS)

To perform electronic-structure calculations for inherently large systems, such as a quantum dots with heterogeneous interfaces, we must perform the calculations over very large unit cells (10^4 to 10^8 atoms). KKR methods typically solve for G by direct inversion G-1, with known analytic form. Using a screened, k-space hybrid KKR, we solve Dyson's equation for the Green's function using a reference state via G = Gref [ I - (t - tref) Gref]-1, scattering matrices t and tref are known and the non-Hermitian tensor Gref is chosen for convenience and sparsity [1]. The approach is O(N) for bandgap materials, whereas it is O(N^2) for metals but with a potentially large prefactor. We use Krylov-space solvers to reduce storage and exploit known symmetries. Parallel iterative and energy contour solves are made also. We explore the numerical efficiency and scaling versus atoms per unit cells. [1] Smirnov and Johnson, Comp! ^1Phys. Comm. 148, 74-80 (2002).

Khan, Suffian; Johnson, Duane

2010-03-01

258

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

SciTech Connect

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

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

2012-01-01

259

Development and demonstration of a supercritical helium-cooled cryogenic viscous compressor prototype for the iter vacuum system  

NASA Astrophysics Data System (ADS)

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

Duckworth, Robert C.; Baylor, Larry R.; Meitner, Steven J.; Combs, Stephen K.; Rasmussen, David A.; Hechler, Michael; Edgemon, Timothy; Barbier, Charlotte; Pearce, Robert; Kersevan, Roberto; Dremel, Matthias; Boissin, Jean-Claude

2012-06-01

260

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

Microsoft Academic Search

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

Hiroaki Mukaidani; Hua Xu; Koichi Mizukami

2001-01-01

261

Fault Diagnosis in Discrete-Event Systems: How to Analyse Algorithm Performance?  

E-print Network

Fault Diagnosis in Discrete-Event Systems: How to Analyse Algorithm Performance? Yannick Pencol´e 1 the fault diagnosis problem in discrete-event systems in an experimental way. To achieve this pur- pose, we an experimental platform based on a tool called DIADES (Diagnosis of Discrete-Event Sys- tems) to run experiments

Pencolé, Yannick

262

Rocket engine system reliability analyses using probabilistic and fuzzy logic techniques  

NASA Technical Reports Server (NTRS)

The reliability of rocket engine systems was analyzed by using probabilistic and fuzzy logic techniques. Fault trees were developed for integrated modular engine (IME) and discrete engine systems, and then were used with the two techniques to quantify reliability. The IRRAS (Integrated Reliability and Risk Analysis System) computer code, developed for the U.S. Nuclear Regulatory Commission, was used for the probabilistic analyses, and FUZZYFTA (Fuzzy Fault Tree Analysis), a code developed at NASA Lewis Research Center, was used for the fuzzy logic analyses. Although both techniques provided estimates of the reliability of the IME and discrete systems, probabilistic techniques emphasized uncertainty resulting from randomness in the system whereas fuzzy logic techniques emphasized uncertainty resulting from vagueness in the system. Because uncertainty can have both random and vague components, both techniques were found to be useful tools in the analysis of rocket engine system reliability.

Hardy, Terry L.; Rapp, Douglas C.

1994-01-01

263

Iterative receivers for OFDM systems with dispersive fading and frequency offset  

E-print Network

. : : : : : : : : : : : : : : : : : : : : : : 47 23 Schematic representation of the MIMO delay spread channel com- posed of multiple clustered paths. Each path cluster has a mean angle of arrival l and an angle spread l. The absolute antenna spacing is denoted by d.... : : : : : : : : : : : : : : : : : : : : : : : : : 49 24 A coded STBC-OFDM system through broad-band correlated MIMO channels. We assumed a total angle spread of 90 degrees and the cluster angle spread l = 0 (l = 0;1;:::;3). Doppler shift fd = 50Hz...

Liu, Hui

2004-09-30

264

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

NASA Technical Reports Server (NTRS)

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

Sidi, Avram; Shapira, Yair

1992-01-01

265

Some results from the second iteration of total-system performance assessment for Yucca Mountain  

SciTech Connect

The second preliminary total-system performance assessment for the potential radioactive-waste-repository site at Yucca Mountain has recently been completed. This paper summarizes results for nominal aqueous and gaseous releases using the composite-porosity flow model. The results are found to be sensitive to the type of unsaturated-zone flow, to percolation flux and climate change, to saturated-zone dilution, to container-wetting processes and container-corrosion processes, to fuel-matrix alteration rate and radionuclide solubilities (especially for {sup 237}Np), and to bulk permeability and retardation of gaseous {sup 14}C. These are areas that should be given priority in the site-characterization program. Specific recommendations are given in the full report of the study.

Wilson, M.L.

1994-05-01

266

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

267

Development and irradiation test of lost alpha detection system for ITER.  

PubMed

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 9.6×10(17)?nm(-2)? s(-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(2)SiO(5) scintillator detector and an Am-Be source to detect the 4.44 MeV high energy gamma ray due to the (9)Be(?,n?)(12)C reaction. PMID:21033839

Nishiura, M; Nagasaka, T; Fujioka, K; Fujimoto, Y; Tanaka, T; Ido, T; Yamamoto, S; Kashiwa, S; Sasao, M

2010-10-01

268

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

PubMed

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

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

2014-01-01

269

Human cardiac systems electrophysiology and arrhythmogenesis: iteration of experiment and computation.  

PubMed

Human cardiac electrophysiology (EP) is a unique system for computational modelling at multiple scales. Due to the complexity of the cardiac excitation sequence, coordinated activity must occur from the single channel to the entire myocardial syncytium. Thus, sophisticated computational algorithms have been developed to investigate cardiac EP at the level of ion channels, cardiomyocytes, multicellular tissues, and the whole heart. Although understanding of each functional level will ultimately be important to thoroughly understand mechanisms of physiology and disease, cardiac arrhythmias are expressly the product of cardiac tissue-containing enough cardiomyocytes to sustain a reentrant loop of activation. In addition, several properties of cardiac cellular EP, that are critical for arrhythmogenesis, are significantly altered by cell-to-cell coupling. However, relevant human cardiac EP data, upon which to develop or validate models at all scales, has been lacking. Thus, over several years, we have developed a paradigm for multiscale human heart physiology investigation and have recovered and studied over 300 human hearts. We have generated a rich experimental dataset, from which we better understand mechanisms of arrhythmia in human and can improve models of human cardiac EP. In addition, in collaboration with computational physiologists, we are developing a database for the deposition of human heart experimental data, including thorough experimental documentation. We anticipate that accessibility to this human heart dataset will further human EP computational investigations, as well as encourage greater data transparency within the field of cardiac EP. PMID:25362174

Holzem, Katherine M; Madden, Eli J; Efimov, Igor R

2014-11-01

270

ITER fast ion collective Thomson scattering  

E-print Network

ITER fast ion collective Thomson scattering Conceptual design of 60 GHz system Fernando Meo, Henrik(EN) Title: ITER fast ion collective Thomson scattering, conceptual design of 60 GHz system. August Fast Ion Collective Thomson Scattering, Feasibility study", contract number EFDA 01.654, ]http

271

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

272

Efficient decentralized iterative learning tracker for unknown sampled-data interconnected large-scale state-delay system with closed-loop decoupling property.  

PubMed

In this paper, an efficient decentralized iterative learning tracker is proposed to improve the dynamic performance of the unknown controllable and observable sampled-data interconnected large-scale state-delay system, which consists of N multi-input multi-output (MIMO) subsystems, with the closed-loop decoupling property. The off-line observer/Kalman filter identification (OKID) method is used to obtain the decentralized linear models for subsystems in the interconnected large-scale system. In order to get over the effect of modeling error on the identified linear model of each subsystem, an improved observer with the high-gain property based on the digital redesign approach is developed to replace the observer identified by OKID. Then, the iterative learning control (ILC) scheme is integrated with the high-gain tracker design for the decentralized models. To significantly reduce the iterative learning epochs, a digital-redesign linear quadratic digital tracker with the high-gain property is proposed as the initial control input of ILC. The high-gain property controllers can suppress uncertain errors such as modeling errors, nonlinear perturbations, and external disturbances (Guo et al., 2000) [18]. Thus, the system output can quickly and accurately track the desired reference in one short time interval after all drastically-changing points of the specified reference input with the closed-loop decoupling property. PMID:21872855

Tsai, Jason Sheng-Hong; Chen, Fu-Ming; Yu, Tze-Yu; Guo, Shu-Mei; Shieh, Leang-San

2012-01-01

273

Iterative Magnetometer Calibration  

NASA Technical Reports Server (NTRS)

This paper presents an iterative method for three-axis magnetometer (TAM) calibration that makes use of three existing utilities recently incorporated into the attitude ground support system used at NASA's Goddard Space Flight Center. The method combines attitude-independent and attitude-dependent calibration algorithms with a new spinning spacecraft Kalman filter to solve for biases, scale factors, nonorthogonal corrections to the alignment, and the orthogonal sensor alignment. The method is particularly well-suited to spin-stabilized spacecraft, but may also be useful for three-axis stabilized missions given sufficient data to provide observability.

Sedlak, Joseph

2006-01-01

274

Iteration with Spreadsheets.  

ERIC Educational Resources Information Center

Presents several examples of the iteration method using computer spreadsheets. Examples included are simple iterative sequences and the solution of equations using the Newton-Raphson formula, linear interpolation, and interval bisection. (YP)

Smith, Michael

1990-01-01

275

Iterative manual control model of human operator.  

PubMed

In this paper, we present an iterative manual control model of a human operator performing some repetitive task. Various aspects of the model are discussed in detail. Experiments have been done to study the human capability to perform the tasks by learning iteratively. Results of the experiments show the ability of the human operator to perform the tracking of a desired trajectory for some unknown non-linear system with quite reasonable accuracy during the iteration process. It is concluded that the human operator performs the repetitive task by modifying his control action using error and error rate in each iteration. During the modification, the human operator assigns different weights to the error and error rate in each iteration. These results can be implemented in designing more efficient iterative learning control algorithms. PMID:10592019

Arif, M; Inooka, H

1999-11-01

276

A Dynamical System Model for Analysing Economic Impacts of Competition upon A Water Company  

E-print Network

been introduced by Government in the Water Act 2003 (WA03), competition between water supply companiesA Dynamical System Model for Analysing Economic Impacts of Competition upon A Water Company Having within England and Wales will take effect on 1 December 2005. It is highly desirable for a water company

Yao, Xin

277

A SYSTEM TO IMPROVE THE SWIMMING START TECHNIQUE USING FORCE RECORDING, TIMING AND KINEMATIC ANALYSES  

Microsoft Academic Search

The purpose of our study was to develop a system to improve the swimmer's starting technique integrating force and video data. A group of elite swimmers (n=17) took part in the study. Cinematic and kinetic variables of the start technique during the block, flight, and swimming phases until the end of the first 10 m were analysed. The horizontal velocity

Raúl Arellano; Susana Pardillo; Blanca De La Fuente; Francisco García

278

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

NASA Technical Reports Server (NTRS)

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

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

2001-01-01

279

Numerical and experimental analyses on the indentation of coated systems with substrates with different mechanical properties  

Microsoft Academic Search

In this work, the indentation of coated systems was studied in terms of the effect of the mechanical properties of the substrate on the film fracture behavior. Both experimental and finite element modeling analyses were conducted to study the phenomena that occur when an indenter with Rockwell C geometry applies normal loads of 400 and 1500 N on titanium nitride

L. A. Piana; E. A. Pérez R; R. M. Souza; A. O. Kunrath; T. R. Strohaecker

2005-01-01

280

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

Microsoft Academic Search

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

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

2002-01-01

281

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

282

The conceptual design of an electron cyclotron emission imaging system for studying ITER-like high temperature plasmas  

NASA Astrophysics Data System (ADS)

The design of an electron cyclotron emission imaging (ECEI) system for two-dimensional (2D) observation of the magnetohydrodynamical modes in high temperature ITER (from ‘International Thermonuclear Experimental Reactor’) H-mode-like plasmas (5.3 T and 25 keV) based on fundamental ordinary mode (O1-mode) and second-harmonic extraordinary mode (X2-mode) measurements is explored conceptually. For studying the spatial resolution in high temperature plasmas, the relativistic broadening and inward shift of the emission layer in the mid-plane are calculated. The radial spatial resolution is significantly degraded in the range R < 5.1 m for the O1-mode and in the range R < 6.9 m for the X2-mode. The region with R < 6.5 m is inaccessible for X2-mode study. The emission layer width is enlarged in a narrow region of the pedestal due to the magnetic field being modified by the large pressure gradient. The broadening and shift in the poloidal plane are also calculated, to investigate their effects on 2D measurements. The frequency range of electron cyclotron emission measurements is selected to protect the system from stray radiations of the 170 GHz electron cyclotron resonance heating source and to avoid harmonic overlap. The frequency ranges of 115–160 GHz for the O1-mode and 230–320 GHz for the X2-mode provide radial coverage of 5.9 < R < 8.2 m or ?0.15 < r/a < 1.The ECEI system utilizes a dual-array detection technique which provides a simultaneous measurement at two radial positions, and each array has 8 by 16 (radial by vertical) channels. The radial image size with 8 channels is ?41–76 cm for the O1-mode and ?19–36 cm for the X2-mode, with sufficient resolution. The front-end optics, which focuses the electron cyclotron emission to the low loss corrugated transmission waveguides, is designed with two flat mirrors and two focusing mini-lens arrays. The vertical image size with 16 channels is ?150 cm and the spot size of each channel is 8–15 cm in the plasma region, taking into account the sensitivity pattern of the waveguide. The refraction effect due to inhomogeneous plasma enlarges the vertical image size up to 20% and 5% for the O1-mode and X2-mode cases, respectively. The horizontal distortion due to the relativistic inwards shift is reduced by the increased toroidal field in the core region.

Lee, W.; Yun, G. S.; Park, H. K.; Nam, Y. B.; Seon, C. R.

2014-09-01

283

Connection between Volterra series and perturbation method in nonlinear systems analyses  

NASA Astrophysics Data System (ADS)

This paper is concerned with the connection between the Volterra series and the regular perturbation method in nonlinear systems analyses. It is revealed for the first time that, for a forced polynomial nonlinear system, if its derived linear system is a damped dissipative system, the steady response obtained through the regular perturbation method is exactly identical to the response given by the Volterra series. On the other hand, if the derived linear system is an undamped conservative system, then the Volterra series is incapable of modeling the forced polynomial nonlinear system. Numerical examples are further presented to illustrate these points. The results provide a new criterion for quickly judging whether the Volterra series is applicable for modeling a given polynomial nonlinear system.

Dong, Xing-Jian; Peng, Zhi-Ke; Zhang, Wen-Ming; Meng, Guang

2014-08-01

284

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

285

Knowledge based system with embedded intelligent heart sound analyser for diagnosing cardiovascular disorders.  

PubMed

Cardiovascular disease (CVD) is the leading cause of death worldwide, and due to the lack of early detection techniques, the incidence of CVD is increasing day by day. In order to address this limitation, a knowledge based system with embedded intelligent heart sound analyser (KBHSA) has been developed to diagnose cardiovascular disorders at early stages. The system analyses digitized heart sounds that are recorded from an electronic stethoscope using advanced digital signal processing and artificial intelligence techniques. KBHSA takes into account data including the patient's personal and past medical history, clinical examination, auscultation findings, chest x-ray and echocardiogram, and provides a list of diseases that it has diagnosed. The system can assist the general physician in making more accurate and reliable diagnosis under emergency conditions where expert cardiologists and advanced equipment are not readily available. To test the validity of the system, abnormal heart sound samples and medical data from 40 patients were recorded and analysed. The diagnoses made by the system were counter checked by four senior cardiologists in Malaysia. The results show that the findings of KBHSA coincide with those of cardiologists. PMID:17701779

Javed, F; Venkatachalam, P A; Hani, A F M

2007-01-01

286

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

NASA Technical Reports Server (NTRS)

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

Eder, D.

1992-01-01

287

The second iteration of the Systems Prioritization Method: A systems prioritization and decision-aiding tool for the Waste Isolation Pilot Plant: Volume 2, Summary of technical input and model implementation  

SciTech Connect

The Systems Prioritization Method (SPM) is a decision-aiding tool developed by Sandia National Laboratories (SNL). SPM provides an analytical basis for supporting programmatic decisions for the Waste Isolation Pilot Plant (WIPP) to meet selected portions of the applicable US EPA long-term performance regulations. The first iteration of SPM (SPM-1), the prototype for SPM< was completed in 1994. It served as a benchmark and a test bed for developing the tools needed for the second iteration of SPM (SPM-2). SPM-2, completed in 1995, is intended for programmatic decision making. This is Volume II of the three-volume final report of the second iteration of the SPM. It describes the technical input and model implementation for SPM-2, and presents the SPM-2 technical baseline and the activities, activity outcomes, outcome probabilities, and the input parameters for SPM-2 analysis.

Prindle, N.H.; Mendenhall, F.T.; Trauth, K.; Boak, D.M. [Sandia National Labs., Albuquerque, NM (United States); Beyeler, W. [Science Applications International Corp., Albuquerque, NM (United States); Hora, S. [Hawaii Univ., Hilo, HI (United States); Rudeen, D. [New Mexico Engineering Research Inst., Albuquerque, NM (United States)

1996-05-01

288

Preliminary Design and Analysis of the DC Reactor for the ITER Converter  

NASA Astrophysics Data System (ADS)

The DC reactor is an important piece of equipment for restraining loop and ripple currents in the international thermonuclear experimental reactor (ITER) converter power supply system. As the reactor is operated at a steady state of 27.5 kA and needs to withstand a peak current of 175 kA, so the design of the DC reactor used in the ITER converter power supply system is necessary. A new water-cooling dry-type air-core reactor is designed in this work. The detailed structural parameters are calculated by theoretical formulas, and then the structure is optimized by electromagnetic simulation with ANSYS. Finally, thermal and dynamic stability analyses are performed to verify the temperature and stress at a rated current of 27.5 kA and pulsed current of 175 kA. The analysis results show that the temperature and stress meet the requirements of the ITER converter power supply system.

Yang, Ning; Zhang, Ming; Li, Chuan; Song, Zhiquan; Yu, Kexun; Zhuang, Ge; Xu, Tao

2014-03-01

289

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

Microsoft Academic Search

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

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

2012-01-01

290

Analyses and tests of the B-1 aircraft structural mode control system  

NASA Technical Reports Server (NTRS)

Analyses and flight tests of the B-1 structural mode control system (SMCS) are presented. Improvements in the total dynamic response of a flexible aircraft and the benefits to ride qualities, handling qualities, crew efficiency, and reduced dynamic loads on the primary structures, were investigated. The effectiveness and the performance of the SMCS, which uses small aerodynamic surfaces at the vehicle nose to provide damping to the structural modes, were evaluated.

Wykes, J. H.; Byar, T. R.; Macmiller, C. J.; Greek, D. C.

1980-01-01

291

Three Dimensional Iterative Reconstruction Techniques in Positron Tomography.  

NASA Astrophysics Data System (ADS)

The acquisition of positron tomographic data in three dimensions is an improvement over the two dimensional acquisition of data because the greater the number of measurements taken of a stochastic process, the more accurately determined the desired parameter may be. This research pursues the goal of three dimensional image reconstruction in Positron Tomography using an iterative approach. This thesis has followed a systematic approach to the exploration of a system for three dimensional iterative reconstruction. System design parameters were discussed such as the advantages and disadvantages of iterative vs analytic methods, the implementation of two, three dimensional iterative algorithms, the selection of a ray passing method, and the choice of an analytic method for comparison to the iterative methods. Several qualitative and quantitative tests were used/developed and performed to analyse and compare the results. Three dimensional reconstruction in Positron Tomography using two iterative techniques (ART and ML-EM) was demonstrated. The ML-EM algorithm was adapted to satisfy the objective of equalizing the estimates with the measurements via division of the sampling density. A new multi-objective function methodology was developed for two dimensions and its extension to three dimensions discussed. A smoothly-varying Gaussian phantom was created for comparing artifacts from different ray passing methods. The analysis of voxel trends over many iterations was used. The use of the output from a two dimensional filtered backprojection algorithm as the seed for three dimensional algorithms to accelerate the reconstruction the was explored. The importance of the selection of a good ray ordering in ART and its effects on the total squared error were explored. For the phantoms studied in this thesis, the ML -EM algorithm tended to perform better under most conditions. This algorithm is slower than ART to achieve both a low total squared error and good contrast, but the dampening of noise in the estimates and the eventual recovery or the contrast makes the ML-EM algorithm an excellent choice for the accurate reconstruction of Positron Tomographic data. Yet, the main drawback of this algorithm is the run time because of the number of iterations required to satisfy the optimization criteria. The ART algorithm produces accurate estimates within two or three iterations in terms of the total squared error, and the appearance of the estimates for the high contrast phantom gave similar visual information to ML -EM more quickly. Additionally, the ML-EM algorithm tends to perform poorer than ART with low contrast cool spots over the first several iterations. The same problem was not apparent for warm spots as the contrast recovered more quickly for the ML-EM algorithm relative to the ART algorithm. The computational cost of one full reconstruction using the (analytic) three dimensional reprojection method is close to five iterations of the three dimensional method (not accounting for the two dimensional Fourier filtering of the projections). The point spread function tests demonstrated through the relative invariance of the width of the PSF with radial position indicates that iterative methods may not suffer from the same PSF variation that three dimensional reprojection methods do.

Sloka, Scott

292

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

293

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

294

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

NASA Technical Reports Server (NTRS)

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

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

1974-01-01

295

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

SciTech Connect

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

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

2009-07-15

296

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

NASA Astrophysics Data System (ADS)

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

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

2013-03-01

297

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

298

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

299

On Iterative Solutions of General Coupled Matrix Equations  

Microsoft Academic Search

In this paper we study coupled matrix equations, which are encountered in many systems and control applications. First, we extend the well-known Jacobi and Gauss-Seidel iterations and present a large family of iterative methods, which are then applied to develop iterative solutions to coupled Sylvester matrix equations. The basic idea is to regard the unknown matrices to be solved as

Feng Ding; Tongwen Chen

2006-01-01

300

Coping with complexity: developmental systems and multilevel analyses in developmental psychopathology.  

PubMed

Developmental psychopathology is not characterized by adherence to one specific theory but instead serves as an organizational framework in which research is driven by a number of key assumptions. In the developmental psychopathology approach, two primary assumptions emphasize the importance of systems thinking and the utility of multilevel analyses. As will be illustrated here, these emphases are inextricably linked: a systems approach necessitates a multilevel approach, such that a level of organization must bring coherence to a level of mechanisms. Given this assumption, coming to an integrative understanding of the relation between levels is of central importance. One broad framework for this endeavor is relational developmental systems, which has been proposed by certain theorists as a new paradigm for developmental science. The implications of embracing this framework include the potential to connect developmental psychopathology with other approaches that emphasize systems thinking and that take an integrative perspective on the problem of levels of analysis. PMID:24342842

Marshall, Peter J

2013-11-01

301

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

NASA Technical Reports Server (NTRS)

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

Stricker, L. T.

1975-01-01

302

The ASSESS (Analytic System and Software for Evaluating Safeguards and Security) Outsider module with multiple analyses  

SciTech Connect

The Analytic System and Software for Evaluating Safeguards and Security (ASSESS) includes modules for analyzing vulnerabilities against outsider and insider adversaries. The ASSESS Outsider Analysis Module has been upgraded to allow for defining, analyzing, and displaying the results of multiple analyses. Once a set of threat definitions have been defined in one Outsider file, they can be readily copied to other Outsider files. This multiple analysis, or batch, mode of operation provides an efficient way of covering the standard DOE outsider threat spectrum. A new approach for coupling the probability of interruption, P(I), values and values calculated by the ASSESS Neutralization module has been implemented in Outsider and is described. An enhanced capability for printing results of these multiple analyses is also included in the upgraded Outside module. 7 refs., 7 figs., 1 tab.

Snell, M.K.; Winblad, A.E. (Sandia National Labs., Albuquerque, NM (USA)); Bingham, B.; Key, B.; Walker, S. (Science and Engineering Associates, Inc., Albuquerque, NM (USA))

1990-01-01

303

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

2013-01-01

304

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

E-print Network

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 dominated 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 also needs to provide 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 fo...

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

2013-01-01

305

Chemical and Solar Electric Propulsion Systems Analyses for Mars Sample Return Missions  

NASA Technical Reports Server (NTRS)

Conceptual in-space transfer stages, including those utilizing solar electric propulsion, chemical propulsion, and chemical propulsion with aerobraking or aerocapture assist at Mars, were evaluated. Roundtrip Mars sample return mission vehicles were analyzed to determine how specific system technology selections influence payload delivery capability. Results show how specific engine, thruster, propellant, capture mode, trip time and launch vehicle technology choices would contribute to increasing payload or decreasing the size of the required launch vehicles. Heliocentric low-thrust trajectory analyses for Solar Electric Transfer were generated with the SEPTOP code.

Donahue, Benjamin B.; Green, Shaun E.; Coverstone, Victoria L.; Woo, Byoungsam

2004-01-01

306

Comparative analyses of amplicon migration behavior in differing denaturing gradient gel electrophoresis (DGGE) systems  

NASA Astrophysics Data System (ADS)

Denaturing gradient gel electrophoresis (DGGE) is commonly utilized to identify and quantify microbial diversity, but the conditions required for different electrophoretic systems to yield equivalent results and optimal resolution have not been assessed. Herein, the influence of different DGGE system configuration parameters on microbial diversity estimates was tested using Symbiodinium, a group of marine eukaryotic microbes that are important constituents of coral reef ecosystems. To accomplish this, bacterial clone libraries were constructed and sequenced from cultured isolates of Symbiodinium for the ribosomal DNA internal transcribed spacer 2 (ITS2) region. From these, 15 clones were subjected to PCR with a GC clamped primer set for DGGE analyses. Migration behaviors of the resulting amplicons were analyzed using a range of conditions, including variation in the composition of the denaturing gradient, electrophoresis time, and applied voltage. All tests were conducted in parallel on two commercial DGGE systems, a C.B.S. Scientific DGGE-2001, and the Bio-Rad DCode system. In this context, identical nucleotide fragments exhibited differing migration behaviors depending on the model of apparatus utilized, with fragments denaturing at a lower gradient concentration and applied voltage on the Bio-Rad DCode system than on the C.B.S. Scientific DGGE-2001 system. Although equivalent PCR-DGGE profiles could be achieved with both brands of DGGE system, the composition of the denaturing gradient and application of electrophoresis time × voltage must be appropriately optimized to achieve congruent results across platforms.

Thornhill, D. J.; Kemp, D. W.; Sampayo, E. M.; Schmidt, G. W.

2010-03-01

307

Iterated Local Search  

Microsoft Academic Search

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

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

2000-01-01

308

SystemLevel Reliability and Sensitivity Analyses for Three FaultTolerant System Architectures  

E-print Network

­Checking Programming). In the system­level reliability modeling domain, fault tree analysis techniques and Markov a combination of fault tree and Markov modeling as a framework for the analysis of hardware and software fault, 1993 Abstract This paper discusses the modeling and analysis of three major fault­tolerant software

Lyu, Michael R.

309

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

ERIC Educational Resources Information Center

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

Haussler, Peter; Pittman, June

310

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

PubMed

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

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

2014-08-01

311

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

PubMed

The underlying requirements for successful implementation of any efficient tumour motion management strategy are regularity and reproducibility of a patient's breathing pattern. The physiological act of breathing is controlled by multiple nonlinear feedback and feed-forward couplings. It would therefore be appropriate to analyse the breathing pattern of lung cancer patients in the light of nonlinear dynamical system theory. The purpose of this paper is to analyse the one-dimensional respiratory time series of lung cancer patients based on nonlinear dynamics and delay coordinate state space embedding. It is very important to select a suitable pair of embedding dimension 'm' and time delay '?' when performing a state space reconstruction. Appropriate time delay and embedding dimension were obtained using well-established methods, namely mutual information and the false nearest neighbour method, respectively. Establishing stationarity and determinism in a given scalar time series is a prerequisite to demonstrating that the nonlinear dynamical system that gave rise to the scalar time series exhibits a sensitive dependence on initial conditions, i.e. is chaotic. Hence, once an appropriate state space embedding of the dynamical system has been reconstructed, we show that the time series of the nonlinear dynamical systems under study are both stationary and deterministic in nature. Once both criteria are established, we proceed to calculate the largest Lyapunov exponent (LLE), which is an invariant quantity under time delay embedding. The LLE for all 16 patients is positive, which along with stationarity and determinism establishes the fact that the time series of a lung cancer patient's breathing pattern is not random or irregular, but rather it is deterministic in nature albeit chaotic. These results indicate that chaotic characteristics exist in the respiratory waveform and techniques based on state space dynamics should be employed for tumour motion management. PMID:21389355

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

2011-04-01

312

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

NASA Astrophysics Data System (ADS)

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

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

2011-04-01

313

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

314

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. PMID:23383313

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

2013-01-01

315

A Simpler Iterative Steady State Solution of M?nch Pressure-Flow Systems Applied to Long and Short Translocation Paths  

PubMed Central

A simple steady state iterative solution of Münch pressure-flow in unbranched sieve tubes containing only water and sucrose is derived. The iterative equations can be solved on a programmable desk calculator. Solutions are presented for steady state transport with specific mass transfer rates up to 1.5 × 10?5 mole second?1 centimeters?2 (= 18.5 grams hour?1 centimeters?2) over distances in excess of 50 meters. The calculations clearly indicate that a Münch pressure-flow system can operate over long distances provided (a) the sieve tube is surrounded by a semipermeable membrane; (b) sugars are actively loaded in one region and unloaded at another; (c) the sieve pores are unblocked so that the sieve tube hydraulic conductivity is high (around 4 centimeters2 second?1 bar?1); (d) the sugar concentration is kept high (around one molar in the source region); and (e) the average sap velocity is kept low (around 20-50 centimeters hour?1). The dimensions of sieve cells in several species of plants are reviewed and sieve tube hydraulic conductivities are calculated; the values range from 0.2 to 20 centimeters2 second?1 bar?1. For long distance pressure-flow to occur, the hydraulic conductivity of the sieve cell membranes must be about 5 × 10?7 centimeters second?1 bar?1 or greater. PMID:16658935

Tyree, Melvin T.; Christy, A. Lawrence; Ferrier, Jack M.

1974-01-01

316

Capabilities and applications of a computer program system for dynamic loads analyses of flexible airplanes with active controls /DYLOFLEX/  

NASA Technical Reports Server (NTRS)

This paper describes and illustrates the capabilities of the DYLOFLEX Computer Program System. DYLOFLEX is an integrated system of computer programs for calculating dynamic loads of flexible airplanes with active control systems. A brief discussion of the engineering formulation for each of the nine DYLOFLEX programs is described. The capabilities of the system are illustrated by the analyses of two example configurations.

Perry, B., III; Goetz, R. C.; Kroll, R. I.; Miller, R. D.

1979-01-01

317

52 IEEE TRANSACTIONS ON SYSTEMS, MAN, AND CYBERNETICS--PART A: SYSTEMS AND HUMANS, VOL. 33, NO. 1, JANUARY 2002 Iterated Wavelet Transformation and Signal  

E-print Network

, JANUARY 2002 Iterated Wavelet Transformation and Signal Discrimination for HRR Radar Target Recognition in the target recognition problem using high range resolution (HRR) radar signals in an air to air scenario. We resolution (HRR) target recognition has been done by or sponsored by the mil- itary. The approaches taken

Starzyk, Janusz A.

318

Iterative higher derivations: integrability Iterative higher derivations: axiomatization  

E-print Network

Multiplicatively iterative higher derivations D. Homann1 P. Kowalski2 1n/a 2Instytut Matematyczny Uniwersytetu Wrocªawskiego Logic Colloquium 2012, Manchester Homann, Kowalski Higher derivations #12;Iterative higher! = 0 !) Homann, Kowalski Higher derivations #12;Iterative higher derivations: integrability Iterative

Kowalski, Piotr

319

Error analyses and calibration methods with accelerometers for optical angle encoders in rotational inertial navigation systems.  

PubMed

By rotating a strapdown inertial navigation system (INS) over one or more axes, a number of error sources originating from the employed sensors cancel out during the integration process. Rotary angle accuracy has an effect on the performance of rotational INS (RINS). The application of existing calibration methods based on gyroscope measurements is restricted by the structure of the inertial measurement unit (IMU) and scale factor stability of the gyroscope. The multireadhead method has problems in miniaturization and cost. Hence, optical angle encoder calibration methods using accelerometers are proposed, on the basis of navigation error and accuracy requirement analyses for a single-axis RINS. The test results show that the accuracy of calibration methods proposed is higher than 4 arcsec (1?). PMID:24216731

Liu, Fang; Wang, Wei; Wang, Lei; Feng, Peide

2013-11-10

320

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

SciTech Connect

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

WILLIAMS, J.C.

2003-11-15

321

Linear ideal MHD stability calculations for ITER  

SciTech Connect

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

Hogan, J.T.

1988-01-01

322

Assessment of Tools and Data for System-Level Dynamic Analyses  

Microsoft Academic Search

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

Steven J. Piet; Nick R. Soelberg

2011-01-01

323

Iterated Belief Revision  

E-print Network

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

Stalnaker, Robert

324

Correlation analyses of clinical and molecular findings identify candidate biological pathways in systemic juvenile idiopathic arthritis  

PubMed Central

Background Clinicians have long appreciated the distinct phenotype of systemic juvenile idiopathic arthritis (SJIA) compared to polyarticular juvenile idiopathic arthritis (POLY). We hypothesized that gene expression profiles of peripheral blood mononuclear cells (PBMC) from children with each disease would reveal distinct biological pathways when analyzed for significant associations with elevations in two markers of JIA activity, erythrocyte sedimentation rate (ESR) and number of affected joints (joint count, JC). Methods PBMC RNA from SJIA and POLY patients was profiled by kinetic PCR to analyze expression of 181 genes, selected for relevance to immune response pathways. Pearson correlation and Student's t-test analyses were performed to identify transcripts significantly associated with clinical parameters (ESR and JC) in SJIA or POLY samples. These transcripts were used to find related biological pathways. Results Combining Pearson and t-test analyses, we found 91 ESR-related and 92 JC-related genes in SJIA. For POLY, 20 ESR-related and 0 JC-related genes were found. Using Ingenuity Systems Pathways Analysis, we identified SJIA ESR-related and JC-related pathways. The two sets of pathways are strongly correlated. In contrast, there is a weaker correlation between SJIA and POLY ESR-related pathways. Notably, distinct biological processes were found to correlate with JC in samples from the earlier systemic plus arthritic phase (SAF) of SJIA compared to samples from the later arthritis-predominant phase (AF). Within the SJIA SAF group, IL-10 expression was related to JC, whereas lack of IL-4 appeared to characterize the chronic arthritis (AF) subgroup. Conclusions The strong correlation between pathways implicated in elevations of both ESR and JC in SJIA argues that the systemic and arthritic components of the disease are related mechanistically. Inflammatory pathways in SJIA are distinct from those in POLY course JIA, consistent with differences in clinically appreciated target organs. The limited number of ESR-related SJIA genes that also are associated with elevations of ESR in POLY implies that the SJIA associations are specific for SJIA, at least to some degree. The distinct pathways associated with arthritis in early and late SJIA raise the possibility that different immunobiology underlies arthritis over the course of SJIA. PMID:23092393

2012-01-01

325

A novel design strategy for iterative learning and repetitive controllers of systems with a high modal density: Application to active noise control  

NASA Astrophysics Data System (ADS)

This paper describes the application of a novel design strategy for iterative learning and repetitive controllers for systems with a high modal density, presented in the companion paper, on two experimental case studies. Both case studies are examples of active structural acoustic control, where the goal is to reduce the radiated noise using structural actuators. In the first case study, ILC is used to control punching noise. An electrodynamic actuator on the frame of the punching machine is driven by the ILC algorithm which takes advantage of the repetitiveness of the consecutive impacts to reduce noise radiation. In the second case study, an RC algorithm is used to control the noise radiated by rotating machinery, which is often mainly periodic. A piezoelectric actuator incorporated in the bearing is driven by the RC algorithm which is capable of reducing harmonics of the rotational frequency of the shaft. Both applications show the practical usefulness of the novel design strategy.

Stallaert, B.; Pinte, G.; Sas, P.; Desmet, W.; Swevers, J.

2010-02-01

326

System response analyses of base-isolated structures to earthquake ground motions  

SciTech Connect

Seismic isolation is one of the most significant earthquake engineering developments in recent years. This paper describes system response analyses of base-isolated structures to earthquake ground motions. Emphasis is placed on the adaptation of a nonlinear constitutive model for the elastomeric isolation bearing together with the treatment of foundation embedment for the soil-structure- interaction analysis. The constitutive model requires six input parameters derived from bearing experimental data under sinusoidal loading. The characteristic behavior of bearing, such as the variation of shear modulus and material damping with the change of maximum shear deformation, can be captured closely by the formulation. In the treatment of soil embedment a spring method is utilized to evaluate the foundation input motion as well as soil stiffness and damping. The above features have been incorporated into a three-dimensional system response program, SISEC, developed at Argonne National Laboratory (ANL) (Wang et al. 1991). Sample problems are presented to illustrate the relative response of isolated and unisolated structures. 5 refs., 7 figs.

Wang, C.Y.; Tang, Y. (Argonne National Lab., IL (USA)); Marchertas, A.H. (Northern Illinois Univ., De Kalb, IL (USA))

1991-01-01

327

ITER LIDAR performance analysis.  

PubMed

The core LIDAR Thomson scattering for ITER is specified for core profile measurements with a spatial resolution of 7 cm (a/30) for the range of 500 eV3x10(19) m(-3) at an accuracy of <10% for T(e). These specifications are verified using a full profile Monte Carlo simulation code. In the simulations it is assumed that the input transmission is 50% and the collection transmission is 10% for lambda=300-1200 nm and F/#=6-17. A crucial design decision lies on the choice of laser and detector combination. It is evaluated that the system can meet its spatial and accuracy specifications for higher temperatures of T(e)>5 keV with a combination of a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (lambda(0)=1064 nm, Delta lambda<1 nm, 5 J, and Delta t(FWHM)=250 ps, 5-10 Hz) and S20, GaAs, and GaAsP microchannel plate photomultipliers (Delta t(FWHM)<300 ps, effective quantum efficiency, EQE=3%-4%, and D=18 mm). In order to reach the required T(e) of 500 eV with Nd:YAG first harmonic, this choice requires a development of fast near infrared detectors. PMID:19044544

Beurskens, M N A; Giudicotti, L; Kempenaars, M; Scannell, R; Walsh, M J

2008-10-01

328

ITER LIDAR performance analysisa)  

NASA Astrophysics Data System (ADS)

The core LIDAR Thomson scattering for ITER is specified for core profile measurements with a spatial resolution of 7 cm (a /30) for the range of 500 eV3×1019 m-3 at an accuracy of <10% for Te. These specifications are verified using a full profile Monte Carlo simulation code. In the simulations it is assumed that the input transmission is 50% and the collection transmission is 10% for ? =300-1200 nm and F /#=6-17. A crucial design decision lies on the choice of laser and detector combination. It is evaluated that the system can meet its spatial and accuracy specifications for higher temperatures of Te>5 keV with a combination of a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (?0=1064 nm, ?? <1 nm, 5 J, and ?tFWHM=250 ps, 5-10 Hz) and S20, GaAs, and GaAsP microchannel plate photomultipliers (?tFWHM<300 ps, effective quantum efficiency, EQE=3% -4%, and D =18 mm). In order to reach the required Te of 500 eV with Nd:YAG first harmonic, this choice requires a development of fast near infrared detectors.

Beurskens, M. N. A.; Giudicotti, L.; Kempenaars, M.; Scannell, R.; Walsh, M. J.

2008-10-01

329

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

SciTech Connect

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

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

1990-11-01

330

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

SciTech Connect

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

Robinson, Gene

2011-03-23

331

Preliminary analyses of WL experiment No. 701, space environment effects on operating fiber optic systems  

NASA Technical Reports Server (NTRS)

A brief overview of the analyses performed to date on WL Experiment-701 is presented. Four active digital fiber optic links were directly exposed to the space environment for a period of 2114 days. The links were situated aboard the Long Duration Exposure Facility (LDEF) with the cabled, single fiber windings atop an experimental tray containing instrumentation for exercising the experiment in orbit. Despite the unplanned and prolonged exposure to trapped and galactic radiation, wide temperature extremes, atomic oxygen interactions, and micro-meteorite and debris impacts, in most instances the optical data links performed well within the experimental limits. Analysis of the recorded orbital data clearly indicates that fiber optic applications in space will meet with success. Ongoing tests and analysis of the experiment at the Phillips Laboratory's Optoelectronics Laboratory will expand this premise, and establish the first known and extensive database of active fiber optic link performance during prolonged space exposure. WL Exp-701 was designed as a feasibility demonstration for fiber optic technology in space applications, and to study the performance of operating fiber systems exposed to space environmental factors such as galactic radiation, and wide temperature cycling. WL Exp-701 is widely acknowledged as a benchmark accomplishment that clearly demonstrates, for the first time, that fiber optic technology can be successfully used in a variety of space applications.

Taylor, E. W.; Berry, J. N.; Sanchez, A. D.; Padden, R. J.; Chapman, S. P.

1992-01-01

332

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

2011-01-01

333

EDITORIAL: ECRH physics and technology in ITER  

NASA Astrophysics Data System (ADS)

It is a great pleasure to introduce you to this special issue containing papers from the 4th IAEA Technical Meeting on ECRH Physics and Technology in ITER, which was held 6-8 June 2007 at the IAEA Headquarters in Vienna, Austria. The meeting was attended by more than 40 ECRH experts representing 13 countries and the IAEA. Presentations given at the meeting were placed into five separate categories EC wave physics: current understanding and extrapolation to ITER Application of EC waves to confinement and stability studies, including active control techniques for ITER Transmission systems/launchers: state of the art and ITER relevant techniques Gyrotron development towards ITER needs System integration and optimisation for ITER. It is notable that the participants took seriously the focal point of ITER, rather than simply contributing presentations on general EC physics and technology. The application of EC waves to ITER presents new challenges not faced in the current generation of experiments from both the physics and technology viewpoints. High electron temperatures and the nuclear environment have a significant impact on the application of EC waves. The needs of ITER have also strongly motivated source and launcher development. Finally, the demonstrated ability for precision control of instabilities or non-inductive current drive in addition to bulk heating to fusion burn has secured a key role for EC wave systems in ITER. All of the participants were encouraged to submit their contributions to this special issue, subject to the normal publication and technical merit standards of Nuclear Fusion. Almost half of the participants chose to do so; many of the others had been published in other publications and therefore could not be included in this special issue. The papers included here are a representative sample of the meeting. The International Advisory Committee also asked the three summary speakers from the meeting to supply brief written summaries (O. Sauter: EC wave physics and applications, M. Thumm: Source and transmission line development, and S. Cirant: ITER specific system designs). These summaries are included in this issue to give a more complete view of the technical meeting. Finally, it is appropriate to mention the future of this meeting series. With the ratification of the ITER agreement and the formation of the ITER International Organization, it was recognized that meetings conducted by outside agencies with an exclusive focus on ITER would be somewhat unusual. However, the participants at this meeting felt that the gathering of international experts with diverse specialities within EC wave physics and technology to focus on using EC waves in future fusion devices like ITER was extremely valuable. It was therefore recommended that this series of meetings continue, but with the broader focus on the application of EC waves to steady-state and burning plasma experiments including demonstration power plants. As the papers in this special issue show, the EC community is already taking seriously the challenges of applying EC waves to fusion devices with high neutron fluence and continuous operation at high reliability.

Luce, T. C.

2008-05-01

334

Iterative ghost imaging.  

PubMed

The recovered image in ghost imaging (GI) contains an error term when the number of measurements M is limited. By iteratively calculating the high-order error term, the iterative ghost imaging (IGI) approach reconstructs a better image, compared to one recovered using a traditional GI approach, without adding complexity. We first propose an experimental scheme, for which IGI can be realized, namely the narrowed point spread function and exponentially increased signal-to-noise ratio (SNR) are realized. The exponentially increasing SNR when implementing IGI results from the replacement of M with Mk. Thus, a perfect recovery of the unknown object is demonstrated with M slightly bigger than the number of speckles in a typical light field. Based on our theoretical framework from the angle of high-order correlation Rk, the two critical behaviors of the iterative coefficients ? and the measurements M are derived and well explained. PMID:25166096

Wang, Wei; Wang, Yan Pu; Li, Jiahua; Yang, Xiaoxue; Wu, Ying

2014-09-01

335

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

E-print Network

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

Li, Perry Y.

336

Iterative image reconstruction techniques: cardiothoracic computed tomography applications.  

PubMed

Iterative image reconstruction algorithms provide significant improvements over traditional filtered back projection in computed tomography (CT). Clinically available through recent advances in modern CT technology, iterative reconstruction enhances image quality through cyclical image calculation, suppressing image noise and artifacts, particularly blooming artifacts. The advantages of iterative reconstruction are apparent in traditionally challenging cases-for example, in obese patients, those with significant artery calcification, or those with coronary artery stents. In addition, as clinical use of CT has grown, so have concerns over ionizing radiation associated with CT examinations. Through noise reduction, iterative reconstruction has been shown to permit radiation dose reduction while preserving diagnostic image quality. This approach is becoming increasingly attractive as the routine use of CT for pediatric and repeated follow-up evaluation grows ever more common. Cardiovascular CT in particular, with its focus on detailed structural and functional analyses, stands to benefit greatly from the promising iterative solutions that are readily available. PMID:24662334

Cho, Young Jun; Schoepf, U Joseph; Silverman, Justin R; Krazinski, Aleksander W; Canstein, Christian; Deak, Zsuzsanna; Grimm, Jochen; Geyer, Lucas L

2014-07-01

337

Iterative C-derivations and Hopf algebras Iterative -schemes  

E-print Network

-varieties via group scheme actions Piotr Kowalski (joint work with Anand Pillay) Instytut Matematyczny Uniwersytetu Wroclawskiego November 16, 2007 Kowalski Iterative -varieties via group scheme actions #12. Kowalski Iterative -varieties via group scheme actions #12;Iterative C-derivations and Hopf algebras

Kowalski, Piotr

338

Iterative Joint and Interference Nulling/ Cancellation Decoding Algorithms for Multi-Group Space Time Trellis Coded Systems  

E-print Network

for multi-group space time trellis coded (MGSTTC) systems. By considering a single user who transmits simultaneously through K parallel space time trellis encoders, the system can provide high spectral efficiencies is transmitting a space time trellis code. The transmitter will divide the information stream and transmits from

Al-Ghadhban, Samir

339

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.

Dr. Norbert Holtkamp

2010-01-08

340

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

341

Codimension 2 Bifurcations of Iterated Maps  

Microsoft Academic Search

This thesis investigates some properties of discrete-time dynamical systems, generated by iterated maps. In particular we study local bifurcations where two parameters are essential to describe the dynamical properties of the system near a fixed point or a cycle. There are 11 such cases. Knowledge of these bifurcations is important as they form boundary corners of stability regions, which is

H. G. E. Meijer

2006-01-01

342

Assessment of stakeholder perceptions in water infrastructure projects using system-of-systems and binary probit analyses: a case study.  

PubMed

Globally, water management is evolving toward integrating participatory processes for decision-making to increase the sustainability of the decision outcome. Information about the perceptions and concerns of stakeholders needs to be readily available to those involved in the decision-making process early in the planning stage to assist in developing viable alternatives that may be implementable with limited public opposition and engender general consensus among stakeholders. The current literature does not identify an appropriate means to incorporate stakeholder views early in the preliminary planning stages without requiring relatively large time commitments or the physical presence of the key stakeholders for meetings and discussions. This study develops and demonstrates a decision-support framework that incorporates the system-of-systems school of thought with binary probit analysis to aid in efficient participatory processes by providing insight regarding the stakeholders' demographics and select behavioral characteristics in a decision-making process. The methodology first frames the water system as a system-of-systems, an approach that inherently pinpoints the necessity for diverse stakeholder involvement and maps the stakeholders in the system's hierarchy. Then, binary probit analyses are used to quantify the effect of stakeholder characteristics on the likelihood that (1) they perceive or do not perceive a need for new capital-intensive water infrastructure, and (2) they support or oppose new capital-intensive water infrastructure. A water system decision in the Sacramento-San Joaquin Delta serves as a case study to demonstrate the methodology. Data regarding stakeholder beliefs and perceptions were collected via a web-based survey deployed throughout Southern and Central California The study results indicate that individuals between 18 and 25 years, persons living solely with their spouse, persons associated with environmental stakeholder groups, and individuals who follow the news on local water issues have an increased likelihood of public opposition to new water infrastructure in the Sacramento-San Joaquin Delta. These groups would be those targeted to mitigate public opposition by measures such as attempting to promote further discussion, educational outreach, and incorporating incentives such as increasing jobs or incorporating ecosystem rehabilitation efforts around the area impacted by the project. PMID:23872216

Faust, Kasey; Abraham, Dulcy M; DeLaurentis, Dan

2013-10-15

343

Time complexity of iterative-deepening-A  

Microsoft Academic Search

We analyze the time complexity of iterative-deepening-A? (IDA?). We first show how to calculate the exact number of nodes at a given depth of a regular search tree, and the asymptotic brute-force branching factor. We then use this result to analyze IDA? with a consistent, admissible heuristic function. Previous analyses relied on an abstract analytic model, and characterized the heuristic

Richard E. Korf; Michael Reid; Stefan Edelkamp

2001-01-01

344

Optimal parameters for linear second-degree stationary iterative methods  

SciTech Connect

It is shown that the optimal parameters for linear second-degree stationary iterative methods applied to nonsymmetric linear systems can be found by solving the same minimax problem used to find optimal parameters for the Tchebychev iteration. In fact, the Tchebychev iteration is asymptotically equivalent to a linear second-degree stationary method. The method of finding optimal parameters for the Tchebychev iteration given by Manteuffel (Numer. Math., 28, 307-27 (1977)) can be used to find optimal parameters for the stationary method as well. 1 figure.

Manteuffel, T. A.

1980-11-01

345

Lithium test module on ITER/TIBER  

SciTech Connect

ITER/TIBER (ITER) is the U.S. version of the design for the International Thermonuclear Experimental Reactor. The role of ITER is to test nuclear components for fusion power reactors. A major nuclear component to be tested is the breeder blanket and its associated tritium recovery system. To assist in the design of ITER, the engineering design of different blanket systems was done. This report summarizes a design of the tritium recovery system for a liquid lithium blanket, a prime candidate for a fusion power reactor. Objectives of this design were to ensure that a reliable, integrated performance of the tritium recovery system could be demonstrated and that the tritium could be measured. The latter objective permits one to validate the performance of the blanket module. For the tritium recovery system, the contractors and the electrolysis units were sized and costed. The magnetic force on the contactor was assessed. The tritium inventory for the system and the blanket module was calculated. Tritium recovery systems for larger blanket units could be designed using the information developed in this report.

Finn, P.A.

1988-09-01

346

Translating relational queries into iterative programs  

SciTech Connect

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

Freytag, J.C.

1987-01-01

347

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

E-print Network

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 using negative capacitance shunt, the spring constant of piezoelectric actuator can be controlled to extreme values of zero or infinity. Since 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 a piezoelectric actuator by reducing its effective spring constant. The 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 effective spring constant of shunted piezoelectric actuator is presented. An ...

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

2014-01-01

348

Fusion neutron diagnostics on ITER tokamak  

NASA Astrophysics Data System (ADS)

ITER is an experimental nuclear reactor, aiming to demonstrate the feasibility of nuclear fusion realization in order to use it as a new source of energy. ITER is a plasma device (tokamak type) which will be equipped with a set of plasma diagnostic tools to satisfy three key requirements: machine protection, plasma control and physics studies by measuring about 100 different parameters. ITER diagnostic equipment is integrated in several ports at upper, equatorial and divertor levels as well internally in many vacuum vessel locations. The Diagnostic Systems will be procured from ITER Members (Japan, Russia, India, United States, Japan, Korea and European Union) mainly with the supporting structures in the ports. The various diagnostics will be challenged by high nuclear radiation and electromagnetic fields as well by severe environmental conditions (ultra high vacuum, high thermal loads). Several neutron systems with different sensitivities are foreseen to measure ITER expected neutron emission from 1014 up to almost 1021 n/s. The measurement of total neutron emissivity is performed by means of Neutron Flux Monitors (NFM) installed in diagnostic ports and by Divertor Neutron Flux Monitors (DNFM) plus MicroFission Chambers (MFC) located inside the vacuum vessel. The neutron emission profile is measured with radial and vertical neutron cameras. Spectroscopy is accomplished with spectrometers looking particularly at 2.5 and 14 MeV neutron energy. Neutron Activation System (NAS), with irradiation ends inside the vacuum vessel, provide neutron yield data. A calibration strategy of the neutron diagnostics has been developed foreseeing in situ and cross calibration campaigns. An overview of ITER neutron diagnostic systems and of the associated challenging engineering and integration issues will be reported.

Bertalot, L.; Barnsley, R.; Direz, M. F.; Drevon, J. M.; Encheva, A.; Jakhar, S.; Kashchuk, Y.; Patel, K. M.; Arumugam, A. P.; Udintsev, V.; Walker, C.; Walsh, M.

2012-04-01

349

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

Microsoft Academic Search

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

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

2006-01-01

350

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

351

Inverse Analyses Techniques for Parameter Identification in Simulation of Excavation Support System  

E-print Network

1 Inverse Analyses Techniques for Parameter Identification in Simulation of Excavation Support parameters that best represents observed ground movement data associated with a deep excavations in urban are applied to lateral movements from synthetic and real excavations to illustrate various aspects

352

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...

353

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

E-print Network

An Open Source Protein Gel Documentation System for Proteome Analyses Daniel Faller,*, Thomas the GNU license from http://webber.physik.uni-freiburg.de/fallerd/tutorial.htm. The term proteomics-book and additionally offers basic and extendable proteome data analysis facilities. The presented data management

Timmer, Jens

354

Predictability of European air quality: Assessment of 3 years of operational forecasts and analyses by the PREV'AIR system  

E-print Network

of European air quality: Assessment of 3 years of operational forecasts and analyses by the PREV'AIR system, J- ments are still needed to manage and control the impacts of air pollution on health. [3] Facing the challenge of reducing the impacts of air pollution on health, one is left with two options: improving air

Menut, Laurent

355

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

356

Iterative Identification Algorithms for Continuous-Time Systems with Unknown Time Delay in the Presence of Measurement Noise  

NASA Astrophysics Data System (ADS)

This paper considers the identification problem of continuous-time systems with unknown time delay from sampled input-output data. By using a digital pre-filter, an approximated discrete-time estimation model is first derived, in which the system parameters remain in their original form and the time delay need not be an integral multiple of the sampling period. Then an unseparable nonlinear least-squares (UNSEPNLS) method and a separable nonlinear least-squares (SEPNLS) method for identification of transfer function parameters and time delay are derived. Furthermore, an unseparable nonlinear instrumental variable (UNSEPNIV) method and a separable nonlinear instrumental variable (SEPNIV) method are proposed, to eliminate estimate bias due to measurement noise. Simulational results show that the UNSEPNIV and SEPNIV methods yield consistent estimates in the presence of measurement noise.

Yang, Zi-Jiang; Iemura, Hideto; Kanae, Shunshoku; Wada, Kiyoshi

357

Comprehensive safety analysis code system for nuclear fusion reactors I: Model and analyses of overpower events for the International Thermonuclear Experimental Reactor  

Microsoft Academic Search

A comprehensive safety analysis code system has been proposed for the quantitative investigation of the safety of nuclear fusion reactors such as the International Thermonuclear Experimental Reactor (ITER). As a first step, the plasma dynamics and the thermal characteristics of the core internal structures have been developed by a one-point model and a time-dependent one-dimensional heat transfer model, respectively. The

T. Honda; T. Uda; K. Maki; T. Okazaki; Y. Seki; I. Aoki

1994-01-01

358

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

359

An Iteration Aware Multidimensional Data Distribution Prototype for Computing Clusters  

E-print Network

An Iteration Aware Multidimensional Data Distribution Prototype for Computing Clusters Baoqiang Yan, we created a new iteration aware data distribution system that accelerates data transfer between requests from cluster nodes to improve overall performance by reducing the number of latency penalties

Rhodes, Philip J.

360

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

NASA Technical Reports Server (NTRS)

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

1974-01-01

361

Development of the ITER baseline inductive scenario  

NASA Astrophysics Data System (ADS)

Sustainment of Q ˜ 10 operation with a fusion power of ˜500 MW for several hundred seconds is a key mission goal of the ITER Project. Past calculations and simulations predict that these conditions can be produced in high-confinement mode operation (H-mode) at 15 MA relying on only inductive current drive. Earlier development of 15 MA baseline inductive plasma scenarios provided a focal point for the ITER Design Review conducted in 2007-2008. In the intervening period, detailed predictive simulations, supported by experimental demonstrations in existing tokamaks, allow us to assemble an end-to-end specification of this scenario consistent with the final design of the ITER device. Simulations have encompassed plasma initiation, current ramp-up, plasma burn and current ramp-down, and have included density profiles and thermal transport models producing temperature profiles consistent with edge pedestal conditions present in current fusion experiments. These quasi-stationary conditions are maintained due to the presence of edge-localized modes that limit the edge pressure. High temperatures and densities in the pedestal region produce significant edge bootstrap current that must be considered in modelling of feedback control of shape and vertical stability. In this paper we present new results of transport simulations fully consistent with the final ITER design that remain within allowed limits for the coil system and power supplies. These self-consistent simulations increase our confidence in meeting the challenges of the ITER program.

Casper, T.; Gribov, Y.; Kavin, A.; Lukash, V.; Khayrutdinov, R.; Fujieda, H.; Kessel, C.; pre="for the"> ITER Organization,

2014-01-01

362

Numerical analyses for treating diffusion in single-, two- and three-phase binary alloy systems  

NASA Technical Reports Server (NTRS)

Numerical solutions were applicable for planar, cylindrical, or spherical geometries with any diffusion-zone size and any continuous variation of the diffusion coefficient with concentration. Special techniques were included in the analyses to account for differences in molal volumes, initiation and growth of an intermediate phase, disappearance of a phase, and the presence of an initial composition profile in the specimen. A major improvement in solution accuracy was achieved in the two phase analysis by employing a mass conservation criterion to establish the location of the interface rather than the conventional interface-flux-balance criterion. In the three phase analysis, computation time was minimized without sacrificing solution accuracy by treating the three phase problem as a two phase problem when the thickness of the intermediate phase was less than a preset small value. Three computer codes were developed to perform these analyses.

Tenney, D. R.; Unnam, J.

1978-01-01

363

ITER dome fabrication processes  

Microsoft Academic Search

The 3\\/4-ton International Thermonuclear Experimental Reactor (ITER) divertor dome component is fabricated from three dissimilar metals-stainless steel, copper, and tungsten. It is actively cooled to withstand heat loads of 5 MW\\/m2 during nominal operation, transient beat loads of 15 MW\\/m2, for 1-2 seconds, and volumetric heating of 0.5-5 MW\\/m3. The divertor dome is comprised of two subcomponents: a 316L cast

G. W. Wille; D. E. Driemeyer; W. J. Chatterton; K. D. Foreman

1999-01-01

364

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

365

Iterative learning control for biped walking  

Microsoft Academic Search

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

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

2010-01-01

366

System assessment study of the ESA Darwin Mission: concepts trade-off and first iteration design on novel Emma arrangement  

NASA Astrophysics Data System (ADS)

ESA's Darwin mission is devoted to direct detection and spectroscopic characterisation of Earth-like planets in the thermal infrared domain by nulling interferometry in space. This technique requires deep and stable starlight rejection to an efficiency around 106 over the whole spectral band. Darwin is a major target for Thales Alenia Space, and is considered as a strategic part of its programme roadmap. In this paper we present the main outcomes of the Darwin mission study conducted by Thales Alenia Space from Oct. 2005 to Jul. 2007. Studying this mission in depth, our proposed most promising configuration features spacecraft in non planar arrangement (called Emma). It offers the best science return in terms of number of stars detected and sky accessibility while staying compliant with mass and volume constraints of a single Ariane 5 launch. Our solution dramatically alleviates engineering constraints thanks to a fully non deployable concept. As compared to the more conventional planar arrangement (called Charles), Emma suppresses Single Point Failures and spurious flexible modes, thus maximising both the system reliability and the stability of the dynamical environment. Emma is fully compatible with either 3 or 4 collectors.

Ruilier, C.; Krawczyk, R.; Sghedoni, M.; Chanal, O.; Degrelle, C.; Pirson, L.; Simane, O.; Thomas, E.

2007-09-01

367

Field Test of a DHW Distribution System: Temperature and Flow Analyses (Presentation)  

SciTech Connect

This presentation discusses a field test of a DHW distribution system in an occupied townhome. It includes measured fixture flows and temperatures, a tested recirculation system, evaluated disaggregation of flow by measured temperatures, Aquacraft Trace Wizard analysis, and comparison.

Barley, C. D.; Hendron, B.; Magnusson, L.

2010-05-13

368

USING SECURITY ATTACK SCENARIOS TO ANALYSE SECURITY DURING INFORMATION SYSTEMS DESIGN  

E-print Network

Mouratidis School of Computing and Technology, University of East London, England Email: h.mouratidis@uel, England Email: g.manson@uel.ac.uk Keywords: Information Systems Analysis, Systems Engineering

369

Challenges and status of ITER conductor production  

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

370

A decision support system for analysing the impact of water restriction policies  

Microsoft Academic Search

The overall objective of the “Design of a Integrated Ground Water Management System. Application in the aquifer system 08.29 in Mancha Oriental, Spain” project (GESMO), financed by the Spanish government, is to research into new software tools for managing water resources in the agricultural environment. This paper presents a decision support system (DSS) developed within that project. The goal of

B. Recio; J. Ibáñez; F. Rubio; J. A. Criado

2005-01-01

371

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

ERIC Educational Resources Information Center

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

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

2013-01-01

372

Insights into Hypoxic Systemic Responses Based on Analyses of Transcriptional Regulation in Arabidopsis  

PubMed Central

We have adopted a hypoxic treatment system in which only roots were under hypoxic conditions. Through analyzing global transcriptional changes in both shoots and roots, we found that systemic signals may be transduced from roots to trigger responses in tissues not directly subjected to hypoxia. The molecular mechanisms of such systemic responses under flooding are currently largely unknown. Using ontological categorization for regulated genes, a systemic managing program of carbohydrate metabolism was observed, providing an example of how systemic responses might facilitate the survival of plants under flooding. Moreover, a proportion of gene expressions that regulated in shoots by flooding was affected in an ethylene signaling mutation, ein2-5. Many systemic-responsive genes involved in the systemic carbohydrate managing program, hormone responses and metabolism, ubiquitin-dependent protein degradation were also affected in ein2-5. These results suggested an important role of ethylene in mediation of hypoxic systemic responses. Genes associated with abscisic acid (ABA) biosynthesis are upregulated in shoots and down regulated in roots. An ABA signaling mutation, abi4-1, affects expression of several systemic responsive genes. These results suggested that regulation of ABA biosynthesis could be required for systemic responses. The implications of these results for the systemic responses of root-flooded Arabidopsis are discussed. PMID:22194941

Hsu, Fu-Chiun; Chou, Mei-Yi; Peng, Hsiao-Ping; Chou, Shu-Jen; Shih, Ming-Che

2011-01-01

373

How a submarine returns to periscope depth: analysing complex socio-technical systems using Cognitive Work Analysis.  

PubMed

This paper presents the application of Cognitive Work Analysis to the description of the functions, situations, activities, decisions, strategies, and competencies of a Trafalgar class submarine when performing the function of returning to periscope depth. All five phases of Cognitive Work Analysis are presented, namely: Work Domain Analysis, Control Task Analysis, Strategies Analysis, Social Organisation and Cooperation Analysis, and Worker Competencies Analysis. Complex socio-technical systems are difficult to analyse but Cognitive Work Analysis offers an integrated way of analysing complex systems with the core of functional means-ends analysis underlying all of the other representations. The joined-up analysis offers a coherent framework for understanding how socio-technical systems work. Data were collected through observation and interviews at different sites across the UK. The resultant representations present a statement of how the work domain and current activities are configured in this complex socio-technical system. This is intended to provide a baseline, from which all future conceptions of the domain may be compared. The strength of the analysis is in the multiple representations from which the constraints acting on the work may be analysed. Future research needs to challenge the assumptions behind these constraints in order to develop new ways of working. PMID:23702259

Stanton, Neville A; Bessell, Kevin

2014-01-01

374

Measurements, models and techniques to synthesize and analyse IR-systems  

Microsoft Academic Search

It is noted that high-quality IR-imagery and real-time advanced digital image processing have led to increased use during the past decade of electro-optical (EO) systems using the infrared part of the spectrum. A method of meeting the increased demand to synthesize and analyze EO systems is described. The method relies on a minicomputer to specify the EO system, predict performance,

A. Bostrom; R. Kihlen

1980-01-01

375

Development of advanced inductive scenarios for ITER  

NASA Astrophysics Data System (ADS)

Since its inception in 2002, the International Tokamak Physics Activity topical group on Integrated Operational Scenarios (IOS) has coordinated experimental and modelling activity on the development of advanced inductive scenarios for applications in the ITER tokamak. The physics basis and the prospects for applications in ITER have been advanced significantly during that time, especially with respect to experimental results. The principal findings of this research activity are as follows. Inductive scenarios capable of higher normalized pressure (?N ? 2.4) than the ITER baseline scenario (?N = 1.8) with normalized confinement at or above the standard H-mode scaling are well established under stationary conditions on the four largest diverted tokamaks (AUG, DIII-D, JET, JT-60U), demonstrated in a database of more than 500 plasmas from these tokamaks analysed here. The parameter range where high performance is achieved is broad in q95 and density normalized to the empirical density limit. MHD modes can play a key role in reaching stationary high performance, but also define the limits to achieved stability and confinement. Projection of performance in ITER from existing experiments uses empirical scalings and theory-based modelling. The status of the experimental validation of both approaches is summarized here. The database shows significant variation in the energy confinement normalized to standard H-mode confinement scalings, indicating the possible influence of additional physics variables absent from the scalings. Tests using the available information on rotation and the ratio of the electron and ion temperatures indicate neither of these variables in isolation can explain the variation in normalized confinement observed. Trends in the normalized confinement with the two dimensionless parameters that vary most from present-day experiments to ITER, gyroradius and collision frequency, are significant. Regression analysis on the multi-tokamak database has been performed, but it appears that the database is not conditioned sufficiently well to yield a new scaling for this type of plasma. Coordinated experiments on size scaling using the dimensionless parameter scaling approach find a weaker scaling with normalized gyroradius than the standard H-mode scaling. Preliminary studies on scaling with collision frequency show a favourable scaling stronger than the standard H-mode scaling. Coordinated modelling activity has resulted in successful benchmarking of modelling codes in the ITER regime. Validation of transport models using these codes on present-day experiments is in progress, but no single model has been shown to capture the variations seen in the experiments. However, projection to ITER using these models is in general agreement with the favourable projections found with the empirical scalings.

Luce, T. C.; Challis, C. D.; Ide, S.; Joffrin, E.; Kamada, Y.; Politzer, P. A.; Schweinzer, J.; Sips, A. C. C.; Stober, J.; Giruzzi, G.; Kessel, C. E.; Murakami, M.; Na, Y.-S.; Park, J. M.; Polevoi, A. R.; Budny, R. V.; Citrin, J.; Garcia, J.; Hayashi, N.; Hobirk, J.; Hudson, B. F.; Imbeaux, F.; Isayama, A.; McDonald, D. C.; Nakano, T.; Oyama, N.; Parail, V. V.; Petrie, T. W.; Petty, C. C.; Suzuki, T.; Wade, M. R.; the ITPA Integrated Operation Scenario Topical Group Members; the ASDEX-Upgrade Team; the DIII-D Team; EFDA Contributors, JET; the JT-60U Team

2014-01-01

376

Set Theory Applied to Uniquely Define the Inputs to Territorial Systems in Emergy Analyses  

EPA Science Inventory

The language of set theory can be utilized to represent the emergy involved in all processes. In this paper we use set theory in an emergy evaluation to ensure an accurate representation of the inputs to territorial systems. We consider a generic territorial system and we describ...

377

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

SciTech Connect

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

Baring-Gould, I.

2009-04-01

378

The 60 GHz antenna system analyses for intersatellite links, phase B  

NASA Technical Reports Server (NTRS)

The purpose of this study is first to investigate, classify, and compare applicable antenna systems capable of establishing and maintaining intersatellite links at 60 GHz and secondly to select the most applicable system for a detailed conceptual design. The results are to be applicable to the development of intersatellite links at 60 GHz for future programs. Design goals are listed.

1984-01-01

379

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

Microsoft Academic Search

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

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

1997-01-01

380

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

NASA Astrophysics Data System (ADS)

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 and the temperature development inside the nuclear components during these accidents. The analysis of the different accident scenarios has been performed without operation of emergency cooling systems. The results of the analyses indicate that a loss of forced coolant flow through the first wall rapidly causes dryout in the first wall cooling pipes. Following dryout, melting in the first wall starts within about 130 s in case of ongoing plasma burning. In case of large break LOCAs and ongoing plasma burning, melting in the first wall starts about 90 s after accident initiation.

Komen, E. M. J.; Koning, H.

1994-03-01

381

Study of the ITER ICRH system with external matching by means of a mock-up loaded by a variable water load  

NASA Astrophysics Data System (ADS)

A mock-up of the complete antenna array (24 straps grouped in 8 triplets) of the ICRH system with external matching for ITER has been constructed with a length reduction factor of 5. At a frequency increased by the same factor the electrical properties of the full-scale system can be measured in the presence of non-dispersive medium. A movable water tank in front of the array simulates variable plasma loading. Measurements of the matching performances of various external circuit configurations and of the scattering matrix of the system show (i) the non-negligible effect of mutual coupling on load resilient matching by Conjugate T (CT) or hybrid leading to coupling between the matching actuators and the generators and asymmetry in power distribution, (ii) good load resilience of a single CT for the right choice of configuration and number of matching parameters, (iii) the large number of matching solutions for coupled CTs and (iv) the benefit of passive power distribution to the straps. This has been successfully tested in the case of the complete array. The power is passively distributed among the upper half and the bottom half of the 24 radiating straps of the antenna plug. The 4 top and 4 bottom triplets are, respectively, set in parallel outside the antenna plug near a voltage anti-node by means of T junctions. The load resilient matching (VSWR <1.3 for an antenna loading variation of about 1-8 ? m-1) is then obtained by a 4-parameters single CT configuration or a hybrid. The maximum voltage along the line remains equal to the one in the antenna plug and there is a fair power share between the straps. A straightforward robust matching procedure of the complete array is described. The effective radiation resistance of different toroidal and poloidal phasing conditions is measured and compared. The paper also underlines the significant influence of the presence of the electrostatic screen and the resulting increase in the recess of the straps on the reduction of the coupling to the load and of the mutual coupling between the straps.

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

2006-07-01

382

A production-theory-based framework for analysing recycling systems in the e-waste sector  

SciTech Connect

Modern approaches in the production theory of business and management economics propose that objects (e.g. materials) be divided into good, bad or neutral. In transformation processes such as occur in production or recycling this makes it possible to distinguish stringently between the economic revenue of a process and the economic and ecological expenditures for it. This approach can be transferred to entire systems of processes in order to determine the system revenue and the system expenditure. Material flow nets or graphs are used for this purpose. In complex material flow systems it becomes possible to calculate not only the costs, but also the direct and indirect environmental impacts of an individual process or a system revenue (for example a product or the elimination of waste) consistently. The approach permits a stringent analysis as well as different analysis perspectives of a material flow system. It is particularly suitable for closed-loop economic systems in which material backflows occur. With the aid of an example developed jointly with Hewlett Packard Europe, the paper outlines how this approach can be employed in the field of e-waste management.

Schmidt, Mario [Institute of Applied Sciences, Pforzheim University, Tiefenbronner Str. 65, D-75175 Pforzheim (Germany)]. E-mail: mario.schmidt@hs-pforzheim.de

2005-07-15

383

Advanced multi-dimensional method for structural and hydrodynamic analyses of LMFBR piping systems  

SciTech Connect

Maintaining the structural integrity of the piping system of Liquid Metal Fast Breeder Reactors (LMFBRs) is essential to the safe operation of the reactor and steam supply systems. In the safety analysis various transient loads can be imposed on the piping systems, which may pose threats to the integrity of the piping structure. These transient loads can be classified into two categories. The first represents dynamic loads resulting from the hydrodynamic pressure-wave propagation or seismic events. The second represents static or quasi-dynamic loads generated by thermal wave propagation, normal operation transient, or creep phenomena. At Argonne National Laboratory, a multi-dimensional method has been developed for the integrated analysis of piping systems under these transient loading conditions. It utilizes a 2-D implicit finite-difference hydrodynamics in conjunction with a 3-D explicit finite-element structural analysis.

Wang, C.Y.; Zeuch, W.R.

1985-04-09

384

[The design of a cardiac monitoring and analysing system with low power consumption].  

PubMed

The paper deals with a portable analyzing monitor system with liquid crystal display (LCD), which is low in power consumption and suitable for China's specific conditions. Apart from the development of the overall scheme of the system, the paper introduces the design of the hardware and the software. The 80196 single chip microcomputer is used as the central microprocessor to process and real-time electrocardiac signal data. The system have the following functions: five types of arrhythmia analysis, alarm, freeze, and record of automatic paperfeeding. The portable system can be operated by alternate-current (AC) or direct-current (DC). Its hardware circuit is simplified and its software structure is optimized. Multiple low power consumption and LCD unit are adopted in its modular designs. PMID:16104273

Chen, Zhen-cheng; Ni, Li-li; Zhu, Yan-gao; Wang, Hong-yan; Ma, Yan

2002-07-01

385

The 60 GHz antenna system analyses for intersatellite links, phase A  

NASA Technical Reports Server (NTRS)

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 presented: (1) Reflector/fixed feed, (2) Mechanical scan, (3) Electronic scan; and (4) Hybrid mechanical/electronic scan. The 12 candidate antennas were assessed on the basis of a preliminary design and a performance analysis then were scored against 15 weighted parameters. This process resulted in the ranking of the 12 candidates for the two applications, namely, for the geostationary TDAS only with a narrow field of view and for low orbit user satellites with a wide field of view.

1984-01-01

386

Game theoretic analyses for free-riding and whitewashing in P2P systems  

Microsoft Academic Search

Conventional P2P networks do not provide incentives for users. Therefore, users can easily obtain information without themselves contributing any information or service to a P2P community. This leads to the well known free-riding problem. Reputation systems may impose penalties on free-riders to identify and distinguish them from contributors, but these systems are vulnerable to the whitewashing attack. This paper analyzed

Jingcheng Ouyang; Yaping Lin; Siwang Zhou

2008-01-01

387

The Social System of Lariang Tarsiers (Tarsius lariang) as Revealed by Genetic Analyses  

Microsoft Academic Search

Previous sociobiological studies of tarsiers were invariably based on field observations. Sulawesi tarsiers are known for\\u000a monogamous or facultative polygynous social mating systems, but, to date, no data exist to describe the genetic mating system.\\u000a We here bring together behavioral studies and molecular tools for the first time to elucidate mating behavior and kinship\\u000a within a tarsier population. We investigated

Christine Driller; Dyah Perwitasari-Farajallah; Hans Zischler; Stefan Merker

2009-01-01

388

Truncated states obtained by iteration  

E-print Network

Quantum states of the electromagnetic field are of considerable importance, finding potential application in various areas of physics, as diverse as solid state physics, quantum communication and cosmology. In this paper we introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST. A general method to engineer TSI in the running-wave domain is employed, which includes the errors due to the nonidealities of detectors and photocounts.

W. B. Cardoso; N. G. de Almeida

2007-01-06

389

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

SciTech Connect

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

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

2013-01-01

390

Automated failure mode effects and criticality analyses for reliability prediction of multibody mechanical systems  

NASA Astrophysics Data System (ADS)

Reliability is important to ensure both serviceability and safety of a mechanical system. A method for simulation-based Failure Mode Effects and Criticality Analysis (FMECA) for reliability prediction of mechanical systems is presented. This approach integrates recursive formulation for dynamic analysis, failure criteria for failure determination, graphics techniques for collision detection, and new techniques for modifying dynamics model during the simulation. The automated FMECA method developed consists of three libraries and a graphics collision detection technique. First, a library of mechanical failure modes is created using cause-effect relationships for mechanical failure modes. Second, a library of component failure criteria is constructed by collecting different material test data. Third, a library of simulation algorithms and supporting techniques is built by developing simulation technologies to perform FMECA for mechanical failure modes. In addition, the automated FMECA method uses the developed graphics software VDS for collision detection. Finally, this approach is used to investigate the consequences of four failure modes of a vehicle system. The difficulty in formulating mathematical expressions for a damaged mechanical system is resolved by manipulating the number of cut joint constraints and generalized coordinates to implicitly update the original system topology. Formulations for virtual joints are derived, as well as other new techniques to permit multiple failures during a dynamic simulation. A near-minimum set of generalized coordinates is thus retained throughout the dynamic simulation. Four general-purpose dynamics codes are implemented and effects of four mechanical failure modes of a mechanical system are investigated; suspension failure, joint degradation and breakage, joint stiction, and component yielding and breakage. Failure histories as well as Mean Time Between Failure (MTBF) and Mean Time To Failure (MTTF) are obtained. The automated FMECA method developed identifies critical components, critical failure modes, and operating limits of a mechanical system. This information can be used to redesign the critical components, thereby improving the reliability of a mechanical system. Automated FMECA also supports a failure reporting and corrective action system (FRACAS), and the test-analyze-and-fix (TAAF) methodology, and minimization of cost for both hard-prototype building and field tests.

Chiang, Alex Chih-Chien

391

A high-resolution photon-counting breast CT system with tensor-framelet based iterative image reconstruction for radiation dose reduction  

NASA Astrophysics Data System (ADS)

Both computer simulations and experimental phantom studies were carried out to investigate the radiation dose reduction with tensor framelet based iterative image reconstruction (TFIR) for a dedicated high-resolution spectral breast computed tomography (CT) based on a silicon strip photon-counting detector. The simulation was performed with a 10 cm-diameter water phantom including three contrast materials (polyethylene, 8 mg ml−1 iodine and B-100 bone-equivalent plastic). In the experimental study, the data were acquired with a 1.3 cm-diameter polymethylmethacrylate (PMMA) phantom containing iodine in three concentrations (8, 16 and 32 mg ml−1) at various radiation doses (1.2, 2.4 and 3.6 mGy) and then CT images were reconstructed using the filtered-back-projection (FBP) technique and the TFIR technique, respectively. The image quality between these two techniques was evaluated by the quantitative analysis on contrast-to-noise ratio (CNR) and spatial resolution that was evaluated using the task-based modulation transfer function (MTF). Both the simulation and experimental results indicated that the task-based MTF obtained from TFIR reconstruction with one-third of the radiation dose was comparable to that from the FBP reconstruction for low contrast target. For high contrast target, the TFIR was substantially superior to the FBP reconstruction in terms of spatial resolution. In addition, TFIR was able to achieve a factor of 1.6–1.8 increase in CNR, depending on the target contrast level. This study demonstrates that the TFIR can reduce the required radiation dose by a factor of two-thirds for a CT image reconstruction compared to the FBP technique. It achieves much better CNR and spatial resolution for high contrast target in addition to retaining similar spatial resolution for low contrast target. This TFIR technique has been implemented with a graphic processing unit system and it takes approximately 10 s to reconstruct a single-slice CT image, which can potentially be used in a future multi-slit multi-slice spiral CT system.

Ding, Huanjun; Gao, Hao; Zhao, Bo; Cho, Hyo-Min; Molloi, Sabee

2014-10-01

392

A high-resolution photon-counting breast CT system with tensor-framelet based iterative image reconstruction for radiation dose reduction.  

PubMed

Both computer simulations and experimental phantom studies were carried out to investigate the radiation dose reduction with tensor framelet based iterative image reconstruction (TFIR) for a dedicated high-resolution spectral breast computed tomography (CT) based on a silicon strip photon-counting detector. The simulation was performed with a 10?cm-diameter water phantom including three contrast materials (polyethylene, 8?mg?ml(-1) iodine and B-100 bone-equivalent plastic). In the experimental study, the data were acquired with a 1.3?cm-diameter polymethylmethacrylate (PMMA) phantom containing iodine in three concentrations (8, 16 and 32?mg?ml(-1)) at various radiation doses (1.2, 2.4 and 3.6?mGy) and then CT images were reconstructed using the filtered-back-projection (FBP) technique and the TFIR technique, respectively. The image quality between these two techniques was evaluated by the quantitative analysis on contrast-to-noise ratio (CNR) and spatial resolution that was evaluated using the task-based modulation transfer function (MTF). Both the simulation and experimental results indicated that the task-based MTF obtained from TFIR reconstruction with one-third of the radiation dose was comparable to that from the FBP reconstruction for low contrast target. For high contrast target, the TFIR was substantially superior to the FBP reconstruction in terms of spatial resolution. In addition, TFIR was able to achieve a factor of 1.6-1.8 increase in CNR, depending on the target contrast level. This study demonstrates that the TFIR can reduce the required radiation dose by a factor of two-thirds for a CT image reconstruction compared to the FBP technique. It achieves much better CNR and spatial resolution for high contrast target in addition to retaining similar spatial resolution for low contrast target. This TFIR technique has been implemented with a graphic processing unit system and it takes approximately 10?s to reconstruct a single-slice CT image, which can potentially be used in a future multi-slit multi-slice spiral CT system. PMID:25230204

Ding, Huanjun; Gao, Hao; Zhao, Bo; Cho, Hyo-Min; Molloi, Sabee

2014-10-21

393

Land mobile satellite communication system. Volume 3: Annexes to volume 2: Particular aspects of market analyses  

NASA Astrophysics Data System (ADS)

The socioeconomic desirability in terms of market demand, technical economic feasibility, and price-performance for a Land Mobile Communication system ground based and/or satellite aided, able to satisfy the request of the traffic demand, foreseeable in the 1995 to 2005 time frame, for the Western European countries was assessed. The criterion of economic value of the mobile system is considered as the driving element. Data on traffic; socioeconomic factors; economic factors; and radiotelephony, paging, and dispatch subscription and value for money trends are presented.

Carnebianca, C.; Pavesi, B.; Tuozzi, A.; Capone, R.

1986-06-01

394

Systems Performance Analyses of Alaska Wind-Diesel Projects; Selawik, Alaska (Fact Sheet)  

SciTech Connect

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

Baring-Gould, I.

2009-04-01

395

Modeling and analysing ubiquitous systems Amara Touil, Jean Vareille, Fred Lherminier, and Philippe Le Parc  

E-print Network

of industrial activities during the last decades and the diversity of industrial products require standards industrial partner Terra Nova Energy (TNE). Keywords: Model Driven Engineering, Analysis, Telecontrol Systems solutions for data mining in the fields of electricity, hydraulic and pulse-energy. It integrates sensing

Paris-Sud XI, Université de

396

Parent Ratings of Children's Social Skills: Longitudinal Psychometric Analyses of the Social Skills Rating System  

ERIC Educational Resources Information Center

The assessment of children's social skills is an important task for school psychologists in both applied and research settings. The present study examines the psychometric properties of parent ratings of the Social Skills Rating System (SSRS), in kindergarten through third grades, testing for measurement differences between boys and girls, between…

Van Horn, M. Lee; Atkins-Burnett, Sally; Karlin, Emilie; Ramey, Sharon Landesman; Snyder, Scott

2007-01-01

397

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

E-print Network

proven practical and effective for numerous software engineering applications, including program veri Carnauba, a practical and effective end-to-end system that extends model checking of temporal logic 2000 and a Ph.D. in August 2004. He was wed to Amanda Holland-Minkley, who he met and fell in love

Pingali, Keshav K.

398

Analysing the Performance of Optimistic Synchronisation Algorithms in Simulations of Multi-Agent Systems  

Microsoft Academic Search

In this paperwe present a detailed analysisof the perfor- mance of the Decision Theoretic Read Delay (DTRD) opti- mistic synchronisation algorithm for simulations of Multi- Agent Systems. We develop an abstract characterisation of the access patterns found in MAS simulations based on the simulation's degree of coupling and skew. Using this char- acterisation, we generatedstereotypicaltest cases which we used to

Michael Lees; Brian Logan; Dan Chen; Ton Oguara; Georgios K. Theodoropoulos

2006-01-01

399

An Earthquake Prediction System Using The Time Series Analyses of Earthquake Property And Crust Motion  

SciTech Connect

We have developed a short-term deterministic earthquake (EQ) forecasting system similar to those used for Typhoons and Hurricanes, which has been under a test operation at website http://www.tec21.jp/ since June of 2003. We use the focus and crust displacement data recently opened to the public by Japanese seismograph and global positioning system (GPS) networks, respectively. Our system divides the forecasting area into the five regional areas of Japan, each of which is about 5 deg. by 5 deg. We have found that it can forecast the focus, date of occurrence and magnitude (M) of an impending EQ (whose M is larger than about 6), all within narrow limits. We have two examples to describe the system. One is the 2003/09/26 EQ of M 8 in the Hokkaido area, which is of hindsight. Another is a successful rollout of the most recent forecast on the 2004/05/30 EQ of M 6.7 off coast of the southern Kanto (Tokyo) area.

Takeda, Fumihide [Takeda Engineering Consultant Inc., 2-14-23 Ujina Miyuki, Hiroshima, 734-0015 (Japan); Takeo, Makoto [Department of Physics, Portland State University, P.O. Box 751, Portland, OR, 97207-0751 (United States)

2004-12-09

400

A New Student Performance Analysing System Using Knowledge Discovery in Higher Educational Databases  

ERIC Educational Resources Information Center

Knowledge discovery is a wide ranged process including data mining, which is used to find out meaningful and useful patterns in large amounts of data. In order to explore the factors having impact on the success of university students, knowledge discovery software, called MUSKUP, has been developed and tested on student data. In this system a…

Guruler, Huseyin; Istanbullu, Ayhan; Karahasan, Mehmet

2010-01-01

401

Social-Ecological Transformations of Supply Systems. Analysing Interactions of Provision and Demographic Change  

Microsoft Academic Search

Every society faces the task of providing its people with basic goods such as water, food or energy. Meeting basic needs and ensuring quality of life, while not deteriorating ecological conditions, provide the normative framework for structures of provision. Therefore, societies have developed specific structures and forms of regulation. Within Social Ecology these structures are conceptual- ised as supply systems,

2007-01-01

402

Analysing farming systems with Data Envelopment Analysis: citrus farming in Spain  

Microsoft Academic Search

Farming systems in the Mediterranean agricultural areas of Spain are frequently characterised by the small size of the production units and a widespread strategy of externalisation of many growing tasks which could be seen as a way of allowing farms to remain competitive. In this paper, we suggest Data Envelopment Analysis as an appropriate analytical tool to explore the possibilities

Ernest Reig-Mart??nez; Andres J. Picazo-Tadeo

2004-01-01

403

Analysing the role of fusion power in the future global energy system  

NASA Astrophysics Data System (ADS)

This work presents the EFDA Times model (ETM), developed within the European Fusion Development Agreement (EFDA). ETM is an optimization global energy model which aims at providing the optimum energy system composition in terms of social wealth and sustainability including fusion as an alternative technology in the long term. Two framework scenarios are defined: a Base case scenario with no limits to CO2 emissions, and a 450ppm scenario with a limit of 450ppm in CO2-eq concentrations set by 2100. Previous results showed that in the Base case scenario, with no measures for CO2 emission reductions, fusion does not enter the energy system. However, when CO2 emission restrictions are imposed, the global energy system composition changes completely. In a 450ppm scenario, coal technologies disappear in a few decades, being mainly replaced by nuclear fission technologies which experience a great increase when constrained only by Uranium resources exhaustion. Fission technologies are then replaced by the fusion power plants that start in 2070, with a significant contribution to the global electricity production by 2100. To conclude the work, a sensitivity analysis will be presented on some parameters that may affect the possible role of fusion in the future global energy system. Note to the reader: The article number has been corrected on web pages on November 22, 2013.

Cabal, H.; Lechón, Y.; Ciorba, U.; Gracceva, F.; Eder, T.; Hamacher, T.; Lehtila, A.; Biberacher, M.; Grohnheit, P. E.; Ward, D.; Han, W.; Eherer, C.; Pina, A.

2012-10-01

404

Analysing the role of fusion power in the future global energy system  

NASA Astrophysics Data System (ADS)

This work presents the EFDA Times model (ETM), developed within the European Fusion Development Agreement (EFDA). ETM is an optimization global energy model which aims at providing the optimum energy system composition in terms of social wealth and sustainability including fusion as an alternative technology in the long term. Two framework scenarios are defined: a Base case scenario with no limits to CO2 emissions, and a 450ppm scenario with a limit of 450ppm in CO2-eq concentrations set by 2100. Previous results showed that in the Base case scenario, with no measures for CO2 emission reductions, fusion does not enter the energy system. However, when CO2 emission restrictions are imposed, the global energy system composition changes completely. In a 450ppm scenario, coal technologies disappear in a few decades, being mainly replaced by nuclear fission technologies which experience a great increase when constrained only by Uranium resources exhaustion. Fission technologies are then replaced by the fusion power plants that start in 2070, with a significant contribution to the global electricity production by 2100. To conclude the work, a sensitivity analysis will be presented on some parameters that may affect the possible role of fusion in the future global energy system.

Cabal, H.; Lechón, Y.; Ciorba, U.; Gracceva, F.; Eder, T.; Hamacher, T.; Lehtila, A.; Biberacher, M.; Grohnheit, P. E.; Ward, D.; Han, W.; Eherer, C.; Pina, A.

2012-10-01

405

Parent Ratings of Children's Social Skills: Longitudinal Psychometric Analyses of the Social Skills Rating System  

Microsoft Academic Search

The assessment of children's social skills is an important task for school psychologists in both applied and research settings. The present study examines the psychometric properties of parent ratings of the Social Skills Rating System (SSRS), in kindergarten through third grades, testing for measurement differences between boys and girls, between African American, Caucasian, and Hispanic children, and across time from

M. Lee Van Horn; Sally Atkins-Burnett; Emilie Karlin; Sharon Landesman Ramey; Scott Snyder

2007-01-01

406

An automatic particle analyser system using an off-line digital computer  

Microsoft Academic Search

An investigation of an automatic particle analyzer which measures the size distribution and the mean diameters of atomized liquid droplets was carried out. The scheme of the whole system was as follows. A photograph of particles was put on a drum which rotated at a constant speed and was scanned with a focused light beam. The signals, corresponding to the

M. Sato; K. Shimizu; T. Sakai

1977-01-01

407

Assessment of plasma parameters for the low activation phase of ITER operation  

NASA Astrophysics Data System (ADS)

An assessment of ITER plasma parameters is carried out for the low activation phase that is required for commissioning the basic ITER systems including plasma control, heating and current drive. Such an operation is analysed for hydrogen, helium and deuterium plasmas for full field and current, as well as with magnetic field and plasma current reduced to half of their design values, B0 = 2.65 T, Ip = 7.5 MA. Both hydrogen and deuterium neutral beam injection (NBI) are considered. We assess the possible domain for safe operation, and the possible target plasmas for commissioning the NBI, electron cyclotron heating (ECH) and ion cyclotron heating (ICH) systems, taking into account the constraints imposed by NB shine-through loss, Greenwald limit and access to H-mode operation. Simulations with the Automated System for Transport Analysis (ASTRA) show that for 33 MW of NBI with 20 MW of ECH, H-mode access is marginal for hydrogen plasmas. Good H-mode confinement, expected at PNB + PEC + PIC > 1.5 PL-H, is more likely for the helium and deuterium cases. It is found that plasma parameters, such as normalized beta, plasma density and current flat-top duration, for full power/half field/half current operation can be similar to those required for the DT long pulse operation. Preliminary assessment is also made of the maximum of tritium and neutron yield achievable in a single shot at the deuterium phase of ITER operation.

Polevoi, A. R.; Campbell, D. J.; Chuyanov, V. A.; Houlberg, W.; Ivanov, A. A.; Kukushkin, A. S.; Lamalle, P.; Loarte, A.; Mukhovatov, V. S.; Oikawa, T.

2013-12-01

408

Game theoretic analyses for free-riding and whitewashing in P2P systems  

NASA Astrophysics Data System (ADS)

Conventional P2P networks do not provide incentives for users. Therefore, users can easily obtain information without themselves contributing any information or service to a P2P community. This leads to the well known free-riding problem. Reputation systems may impose penalties on free-riders to identify and distinguish them from contributors, but these systems are vulnerable to the whitewashing attack. This paper analyzed the Tit-for-Tat protocol in the presence of whitewashers using a game theoretic approach. The Tit-for-Tat protocol is not an evolutionary stable strategy against invasion of whitewashing, but imposing an appropriate identity cost helps in preventing invasion by whitewashers. Simulation results demonstrated the theoretic analysis, and showed that the percentage of cooperating nodes in P2P networks with an appropriate identity cost is nearly four times bigger than without any identity cost.

Ouyang, Jingcheng; Lin, Yaping; Zhou, Siwang

2008-10-01

409

Iteration-complexity of first-order augmented Lagrangian methods ...  

E-print Network

Apr 30, 2009 ... ... Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, .... methods (with pre-specified number of outer-iterations) to (1) until a near ... vector space inherited with a inner product space ?·,·? and use · to ...

2009-05-14

410

Plans for U.S. Contributions to ITER  

E-print Network

wire #12;Magnet Systems USIPO U.S. ITER Technical Advisory Committee August 13-14, 2008 8 Cable pattern Technical Advisory Committee August 13-14, 2008 8 Cable pattern & strand support Baseline geometry 3-based

411

Methodologies to Perform GNC Design and Analyses for Complex Dynamic Systems Using Multibody Software  

Microsoft Academic Search

\\u000a Virtual simulation is currently a key activity that supports the specification, design, verification and operations of space\\u000a systems. Taking advantage of dynamics research activities, ESA has currently been developing a multibody software (DCAP) together\\u000a with industry for more than 30 years heritage in space applications. This software is a suite of fast, effective computer\\u000a programs that provides the user with

G. Baldesi; T. Voirin; A. Martinez Barrio; M. Claeys

412

Combining Dynamic Systems and Multivariate Analyses to Compare the Mother–Child Interactions of Externalizing Subtypes  

Microsoft Academic Search

A dynamic systems analysis was conducted to distinguish the parent–child interactions of “pure” externalizing children from children comorbid for externalizing and internalizing problems. Thirty-three parents and clinically referred children (8–12 years old) discussed a problem for 4 min and then tried to “wrap up” in response to a signal (a perturbation). The perturbation was intended to increase the pressure on

Isabela Granic; Alex V. Lamey

2002-01-01

413

Analyses of Unprotected Transients in the Lead\\/Bismuth-Cooled Accelerator Driven System PDS-XADS  

Microsoft Academic Search

Safety investigations for the lead\\/bismuth (Pb\\/Bi)-cooled experimental accelerator driven system (XADS) were performed with the computational code SIMMER-III. The code has been extended so as to describe the ADS configuration with heavy-metal coolant, sub-critical core and strong external neutron source. As transient scenarios, unprotected loss of flow (ULOF), unprotected subassembly blockage and unprotected transient over-power (UTOP) were simulated. The calculation

Tohru Suzuki; Xue-Nong Chen; Andrei Rineiski; Werner Maschek

414

Genomic and proteomic analyses of the agarolytic system expressed by Saccharophagus degradans 2-40.  

PubMed

Saccharophagus degradans 2-40 (formerly Microbulbifer degradans 2-40) is a marine gamma-subgroup proteobacterium capable of degrading many complex polysaccharides, such as agar. While several agarolytic systems have been characterized biochemically, the genetics of agarolytic systems have been only partially determined. By use of genomic, proteomic, and genetic approaches, the components of the S. degradans 2-40 agarolytic system were identified. Five agarases were identified in the S. degradans 2-40 genome. Aga50A and Aga50D include GH50 domains. Aga86C and Aga86E contain GH86 domains, whereas Aga16B carries a GH16 domain. Novel family 6 carbohydrate binding modules (CBM6) were identified in Aga16B and Aga86E. Aga86C has an amino-terminal acylation site, suggesting that it is surface associated. Aga16B, Aga86C, and Aga86E were detected by mass spectrometry in agarolytic fractions obtained from culture filtrates of agar-grown cells. Deletion analysis revealed that aga50A and aga86E were essential for the metabolism of agarose. Aga16B was shown to endolytically degrade agarose to release neoagarotetraose, similarly to a beta-agarase I, whereas Aga86E was demonstrated to exolytically degrade agarose to form neoagarobiose. The agarolytic system of S. degradans 2-40 is thus predicted to be composed of a secreted endo-acting GH16-dependent depolymerase, a surface-associated GH50-dependent depolymerase, an exo-acting GH86-dependent agarase, and an alpha-neoagarobiose hydrolase to release galactose from agarose. PMID:16672483

Ekborg, Nathan A; Taylor, Larry E; Longmire, Atkinson G; Henrissat, Bernard; Weiner, Ronald M; Hutcheson, Steven W

2006-05-01

415

Analyses of Entry Mechanisms of Novel Emerging Viruses Using Pseudotype VSV System  

PubMed Central

Emerging infectious diseases include newly identified diseases caused by previously unknown organisms or diseases found in new and expanding geographic areas. Viruses capable of causing clinical disease associated with fever and bleeding are referred to as viral hemorrhagic fevers (VHFs). Arenaviruses and Bunyaviruses, both belonging to families classified as VHFs are considered major etiologies of hemorrhagic fevers caused by emerging viruses; having significant clinical and public health impact. Because these viruses are categorized as Biosafety Level (BSL) 3 and 4 pathogens, restricting their use, biological studies including therapeutic drug and vaccine development have been impeded. Due to these restrictions and the difficulties in handling such live viruses, pseudotype viruses bearing envelope proteins of VHF viruses have been developed using vesicular stomatitis virus (VSV) as a surrogate system. Here, we report the successful developments of two pseudotype VSV systems; bearing the envelope proteins of Lujo virus and severe fever with thrombocytopenia syndrome (SFTS) virus, both recently identified viruses of the family Arenaviridae and Bunyaviridae, respectively. My presentation will summarize the characterization of the envelope proteins of Lujo virus including its cellular receptor use and cell entry mechanisms. In addition, I will also present a brief introduction of SFTS reported in Japan and the diagnostic studies in progress using these newly pseudotype VSV system.

2014-01-01

416

Analysing stratified medicine business models and value systems: innovation-regulation interactions.  

PubMed

Stratified medicine offers both opportunities and challenges to the conventional business models that drive pharmaceutical R&D. Given the increasingly unsustainable blockbuster model of drug development, due in part to maturing product pipelines, alongside increasing demands from regulators, healthcare providers and patients for higher standards of safety, efficacy and cost-effectiveness of new therapies, stratified medicine promises a range of benefits to pharmaceutical and diagnostic firms as well as healthcare providers and patients. However, the transition from 'blockbusters' to what might now be termed 'niche-busters' will require the adoption of new, innovative business models, the identification of different and perhaps novel types of value along the R&D pathway, and a smarter approach to regulation to facilitate innovation in this area. In this paper we apply the Innogen Centre's interdisciplinary ALSIS methodology, which we have developed for the analysis of life science innovation systems in contexts where the value creation process is lengthy, expensive and highly uncertain, to this emerging field of stratified medicine. In doing so, we consider the complex collaboration, timing, coordination and regulatory interactions that shape business models, value chains and value systems relevant to stratified medicine. More specifically, we explore in some depth two convergence models for co-development of a therapy and diagnostic before market authorisation, highlighting the regulatory requirements and policy initiatives within the broader value system environment that have a key role in determining the probable success and sustainability of these models. PMID:22440585

Mittra, James; Tait, Joyce

2012-09-15

417

Non-target screening analyses of organic contaminants in river systems as a base for monitoring measures  

NASA Astrophysics Data System (ADS)

Organic contaminants discharged to the aquatic environment exhibit a high diversity with respect to their molecular structures and the resulting physico-chemical properties. The chemical analysis of anthropogenic contamination in river systems is still an important feature, especially with respect to (i) the identification and structure elucidation of novel contaminants, (ii) to the characterisation of their environmental behaviour and (iii) to their risk for natural systems. A huge proportion of riverine contamination is caused by low-molecular weight organic compounds, like pesticides plasticizers, pharmaceuticals, personal care products, technical additives etc. Some of them, like PCB or PAH have already been investigated thoroughly and, consequently, their behaviour in aqueous systems is very well described. Although analyses on organic substances in river water traditionally focused on selected pollutants, in particular on common priority pollutants which are monitored routinely, the occurrence of further contaminants, e.g. pharmaceuticals, personal care products or chelating agents has received increasing attention within the last decade. Accompanied, screening analyses revealing an enormous diversity of low-molecular weight organic contaminants in waste water effluents and river water become more and more noticed. Since many of these substances have been rarely noticed so far, it will be an important task for the future to study their occurrence and fate in natural environments. Further on, it should be a main issue of environmental studies to provide a comprehensive view on the state of pollution of river water, in particular with respect to lipophilic low molecular weight organic contaminants. However, such non-target-screening analyses has been performed only rarely in the past. Hence, we applied extended non-target screening analyses on longitudinal sections of the rivers Rhine, Rur and Lippe (Germany) on the base of GC/MS analyses. The investigations revealed complex pattern of anthropogenic contaminants comprising a lot of still unnoticed pollutants (e.g. specific sulfones, trifluoromethyl substituted substances, nitrogen heterocycles etc.) or still unidentified compounds (such as selected brominated aromatics) of obviously high environmental relevance. In this presentation, a selection of several different contaminants will be discussed in detail comprising their emission sources, their emission behaviour, their fate within the river water bodies and in particular their structural properties. Generally. this investigation demonstrated the need to expand our analytical focus on a broader spectrum of organic contaminants, in particular to build up an adapted base for advanced monitoring studies.

Schwarzbauer, J.

2009-04-01

418

Compact toroid fuelling for ITER  

Microsoft Academic Search

Deep fuelling of ITER may be achievable by compact toroid (CT) injection. The advantages of deep fuelling include avoiding edge density limits by fuelling beyond the transport barriers, profile peaking to reach ignition, profile control to improve current drive, low tritium inventory, etc. In this paper, a conceptual design of a CT fueller for ITER is presented. In the proposed

R Raman; P Gierszewski

1998-01-01

419

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

420

Analyses of antigen dependency networks unveil immune system reorganization between birth and adulthood  

NASA Astrophysics Data System (ADS)

Much effort has been devoted to assess the importance of nodes in complex biological networks (such as gene transcriptional regulatory networks, protein interaction networks, and neural networks). Examples of commonly used measures of node importance include node degree, node centrality, and node vulnerability score (the effect of the node deletion on the network efficiency). Here, we present a new approach to compute and investigate the mutual dependencies between network nodes from the matrices of node-node correlations. To this end, we first define the dependency of node i on node j (or the influence of node j on node i), D(i, j) as the average over all nodes k of the difference between the i - k correlation and the partial correlations between these nodes with respect to node j. Note that the dependencies, D(i, j) define a directed weighted matrix, since, in general, D(i, j) differs from D( j, i). For this reason, many of the commonly used measures of node importance, such as node centrality, cannot be used. Hence, to assess the node importance of the dependency networks, we define the system level influence (SLI) of antigen j, SLI( j) as the sum of the influence of j on all other antigens i. Next, we define the system level influence or the influence score of antigen j, SLI( j) as the sum of D(i, j) over all nodes i. We introduce the new approach and demonstrate that it can unveil important biological information in the context of the immune system. More specifically, we investigated antigen dependency networks computed from antigen microarray data of autoantibody reactivity of IgM and IgG isotypes present in the sera of ten mothers and their newborns. We found that the analysis was able to unveil that there is only a subset of antigens that have high influence scores (SLI) common both to the mothers and newborns. Networks comparison in terms of modularity (using the Newman's algorithm) and of topology (measured by the divergence rate) revealed that, at birth, the IgG networks exhibit a more profound global reorganization while the IgM networks exhibit a more profound local reorganization. During immune system development, the modularity of the IgG network increases and becomes comparable to that of the IgM networks at adulthood. We also found the existence of several conserved IgG and IgM network motifs between the maternal and newborns networks, which might retain network information as our immune system develops. If correct, these findings provide a convincing demonstration of the effectiveness of the new approach to unveil most significant biological information. Whereas we have introduced the new approach within the context of the immune system, it is expected to be effective in the studies of other complex biological social, financial, and manmade networks.

Madi, Asaf; Kenett, Dror Y.; Bransburg-Zabary, Sharron; Merbl, Yifat; Quintana, Francisco J.; Boccaletti, Stefano; Tauber, Alfred I.; Cohen, Irun R.; Ben-Jacob, Eshel

2011-03-01

421

Root distribution analyses as a means of improving sensor-based deficit irrigation systems  

NASA Astrophysics Data System (ADS)

The limited and seasonally variable availability of water and its efficient distribution when growing crops is still an unsolved problem in agriculture. Sensor-based deficit irrigation (DI), where a sensor is used to detect the soil water status and irrigation is provided according to certain threshold values, is one strategy to address that issue. Threshold values are needed that ensure high water productivity and high reliability. A stochastic approach of simulation and optimization in combination with irrigation experiments of drip irrigated maize for model parameterization was used to derive reliable soil water tension threshold values for irrigation control. A weakness of the applied model was the unknown parameterization of the plant root, which had to be included into the optimization besides parameters for the soil only, thus increasing the complexity of the problem. In a follow-up irrigation experiment with the same DI system parameters, focus was put on the investigation of the plant's root distribution in order to improve the validity of the model when determining optimal soil water tension threshold values in sensor-based deficit irrigation systems. Soil samples for a fully and a deficiently irrigated treatment during different stages of plant development were taken and the root density at different depths was determined. The difference in root growth for both treatments are shown and reliable soil water tension threshold values for varying values of irrigation parameters recalculated in a Monte Carlo simulation, after incorporating the new root parameterization into the model. This further improves the significance of derived threshold values and helps to assess possibilities and limitations of this approach when used for investigating the potentials of sensor-based DI systems.

Kloss, Sebastian; Werisch, Martin; Schütze, Niels

2014-05-01

422

Cycle O (CY 1991) NLS trade studies and analyses, book 2. Part 1: Avionics and systems  

NASA Technical Reports Server (NTRS)

An assessment was conducted to determine the maximum LH2 tank stretch capability based on the constraints of the manufacturing, tooling and facilities at the Michoud Assembly Facility in New Orleans, Louisiana. The maximum tank stretch was determined to be 5 ft. with minor or no modifications, a stretch of 11 ft. with some possible facility modifications and beyond 11 ft. significant new facilities are required. A cost analysis was performed to evaluate the impacts for various stretch lengths. Tasks that were defined to perform trades and studies regarding the best approach to meet requirements for the National Launch System Avionics are also discussed.

Harris, Richard; Kirkland, Zach

1992-01-01

423

Pedigree and mating system analyses in a western larch ( Larix occidentalis Nutt.) experimental population  

Microsoft Academic Search

– \\u000a \\u000a •The mating pattern and gene flow in a western larch (Larix occidentalis Nutt.) experimental population was studied with the aid of microsatellite markers and a combination of paternity-mating system\\u000a analysis. The commonly difficult to assess, male gametic contribution was determined with 95% confidence and its impact on\\u000a genetic gain and diversity was determined.\\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a • Male fertility success rate

Tomas Funda; Charles C. Chen; Cherdsak Liewlaksaneeyanawin; Ahmed M. A. Kenawy; Yousry A. El-Kassaby

2008-01-01

424

Phytophthora community structure analyses in Oregon nurseries inform systems approaches to disease management.  

PubMed

ABSTRACT Nursery plants are important vectors for plant pathogens. Understanding what pathogens occur in nurseries in different production stages can be useful to the development of integrated systems approaches. Four horticultural nurseries in Oregon were sampled every 2 months for 4 years to determine the identity and community structure of Phytophthora spp. associated with different sources and stages in the nursery production cycle. Plants, potting media, used containers, water, greenhouse soil, and container yard substrates were systematically sampled from propagation to the field. From 674 Phytophthora isolates recovered, 28 different species or taxa were identified. The most commonly isolated species from plants were Phytophthora plurivora (33%), P. cinnamomi (26%), P. syringae (19%), and P. citrophthora (11%). From soil and gravel substrates, P. plurivora accounted for 25% of the isolates, with P. taxon Pgchlamydo, P. cryptogea, and P. cinnamomi accounting for 18, 17, and 15%, respectively. Five species (P. plurivora, P. syringae, P. taxon Pgchlamydo, P. gonapodyides, and P. cryptogea) were found in all nurseries. The greatest diversity of taxa occurred in irrigation water reservoirs (20 taxa), with the majority of isolates belonging to internal transcribed spacer clade 6, typically including aquatic opportunists. Nurseries differed in composition of Phytophthora communities across years, seasons, and source within the nursery. These findings suggest likely contamination hazards and target critical control points for management of Phytophthora disease using a systems approach. PMID:24702667

Parke, Jennifer L; Knaus, Brian J; Fieland, Valerie J; Lewis, Carrie; Grünwald, Niklaus J

2014-10-01

425

Iterated crowdsourcing dilemma game  

NASA Astrophysics Data System (ADS)

The Internet has enabled the emergence of collective problem solving, also known as crowdsourcing, as a viable option for solving complex tasks. However, the openness of crowdsourcing presents a challenge because solutions obtained by it can be sabotaged, stolen, and manipulated at a low cost for the attacker. We extend a previously proposed crowdsourcing dilemma game to an iterated game to address this question. We enumerate pure evolutionarily stable strategies within the class of so-called reactive strategies, i.e., those depending on the last action of the opponent. Among the 4096 possible reactive strategies, we find 16 strategies each of which is stable in some parameter regions. Repeated encounters of the players can improve social welfare when the damage inflicted by an attack and the cost of attack are both small. Under the current framework, repeated interactions do not really ameliorate the crowdsourcing dilemma in a majority of the parameter space.

Oishi, Koji; Cebrian, Manuel; Abeliuk, Andres; Masuda, Naoki

2014-02-01

426

Iterated crowdsourcing dilemma game  

E-print Network

The Internet has enabled the emergence of collective problem solving, also known as crowdsourcing, as a viable option for solving complex tasks. However, the openness of crowdsourcing presents a challenge because solutions obtained by it can be sabotaged, stolen, and manipulated at a low cost for the attacker. We extend a previously proposed crowdsourcing dilemma game to an iterated game to address this question. We enumerate pure evolutionarily stable strategies within the class of so-called reactive strategies, i.e., those depending on the last action of the opponent. Among the 4096 possible reactive strategies, we find 16 strategies each of which is stable in some parameter regions. Repeated encounters of the players can improve social welfare when the damage inflicted by an attack and the cost of attack are both small. Under the current framework, repeated interactions do not really ameliorate the crowdsourcing dilemma in a majority of the parameter space.

Oishi, Koji; Abeliuk, Andres; Masuda, Naoki

2014-01-01

427

Analyse des interactions energetiques entre un arena et son systeme de refrigeration  

NASA Astrophysics Data System (ADS)

La presente these s'inscrit dans le cadre d'un projet strategique sur les arenas finance par le CRSNG (Conseil de Recherche en Sciences Naturelles et en Genie du Canada) qui a pour but principal le developpement d'un outil numerique capable d'estimer et d'optimiser la consommation d'energie dans les arenas et curlings. Notre travail s'inscrit comme une suite a un travail deja realise par DAOUD et coll. (2006, 2007) qui a developpe un modele 3D (AIM) en regime transitoire de l'arena Camilien Houde a Montreal et qui calcule les flux de chaleur a travers l'enveloppe du batiment ainsi que les distributions de temperatures et d'humidite durant une annee meteorologique typique. En particulier, il calcule les flux de chaleur a travers la couche de glace dus a la convection, la radiation et la condensation. Dans un premier temps nous avons developpe un modele de la structure sous la glace (BIM) qui tient compte de sa geometrie 3D, des differentes couches, de l'effet transitoire, des gains de chaleur du sol en dessous et autour de l'arena etudie ainsi que de la temperature d'entree de la saumure dans la dalle de beton. Par la suite le BIM a ete couple le AIM. Dans la deuxieme etape, nous avons developpe un modele du systeme de refrigeration (REFSYS) en regime quasi-permanent pour l'arena etudie sur la base d'une combinaison de relations thermodynamiques, de correlations de transfert de chaleur et de relations elaborees a partir de donnees disponibles dans le catalogue du manufacturier. Enfin le couplage final entre l'AIM +BIM et le REFSYS a ete effectue sous l'interface du logiciel TRNSYS. Plusieurs etudes parametriques on ete entreprises pour evaluer les effets du climat, de la temperature de la saumure, de l'epaisseur de la glace, etc. sur la consommation energetique de l'arena. Aussi, quelques strategies pour diminuer cette consommation ont ete etudiees. Le considerable potentiel de recuperation de chaleur au niveau des condenseurs qui peut reduire l'energie requise par le systeme de ventilation de l'arena a ete mis en evidence. Mots cles. Arena, Systeme de refrigeration, Consommation d'energie, Efficacite energetique, Conduction au sol, Performance annuelle.

Seghouani, Lotfi

428

System Analyses of Pneumatic Technology for High Speed Civil Transport Aircraft  

NASA Technical Reports Server (NTRS)

The primary aspiration of this study was to objectively assess the feasibility of the application of a low speed pneumatic technology, in particular Circulation Control (CC) to an HSCT concept. Circulation Control has been chosen as an enabling technology to be applied on a generic High Speed Civil Transport (HSCT). This technology has been proven for various subsonic vehicles including flight tests on a Navy A-6 and computational application on a Boeing 737. Yet, CC has not been widely accepted for general commercial fixed-wing use but its potential has been extensively investigated for decades in wind tunnels across the globe for application to rotorcraft. More recently, an experimental investigation was performed at Georgia Tech Research Institute (GTRI) with application to an HSCT-type configuration. The data from those experiments was to be applied to a full-scale vehicle to assess the impact from a system level point of view. Hence, this study attempted to quantitatively assess the impact of this technology to an HSCT. The study objective was achieved in three primary steps: 1) Defining the need for CC technology; 2) Wind tunnel data reduction; 3) Detailed takeoff/landing performance assessment. Defining the need for the CC technology application to an HSCT encompassed a preliminary system level analysis. This was accomplished through the utilization of recent developments in modern aircraft design theory at Aerospace Systems Design Laboratory (ASDL). These developments include the creation of techniques and methods needed for the identification of technical feasibility show stoppers. These techniques and methods allow the designer to rapidly assess a design space and disciplinary metric enhancements to enlarge or improve the design space. The takeoff and landing field lengths were identified as the concept "show-stoppers". Once the need for CC was established, the actual application of data and trends was assessed. This assessment entailed a reduction of the wind tunnel data from the experiments performed by Mr. Bob Englar at the GTRI. Relevant data was identified and manipulated based on the required format of the analysis tools utilized. Propulsive, aerodynamic, duct sizing, and vehicle sizing investigations were performed and information supplied to a detailed takeoff and landing tool, From the assessments, CC was shown to improve the low speed performance metrics, which were previously not satisfied. An HSCT with CC augmentation does show potential for full-scale application. Yet, an economic assessment of an HSCT with and without CC showed that a moderate penalty was incurred from the increased RDT&E costs associated with developing the CC technology and slight increases in empty weight.

Mavris, Dimitri N.; Tai, Jimmy C.; Kirby, Michelle M.; Roth, Bryce A.

1999-01-01

429

Analysing the relationship between rainfalls and landslides to define a mosaic of triggering thresholds for regional-scale warning systems  

NASA Astrophysics Data System (ADS)

We propose an original approach to develop rainfall thresholds to be used in civil protection warning systems for the occurrence of landslides at regional scale (i.e. tens of thousands of kilometres), and we apply it to Tuscany, Italy (23 000 km2). Purpose-developed software is used to define statistical intensity-duration rainfall thresholds by means of an automated and standardized analysis of rainfall data. The automation and standardization of the analysis brings several advantages that in turn have a positive impact on the applicability of the thresholds to operational warning systems. Moreover, the possibility of defining a threshold in very short times compared to traditional analyses allowed us to subdivide the study area into several alert zones to be analysed independently, with the aim of setting up a specific threshold for each of them. As a consequence, a mosaic of several local rainfall thresholds is set up in place of a single regional threshold. Even if pertaining to the same region, the local thresholds vary substantially and can have very different equations. We subsequently analysed how the physical features of the test area influence the parameters and the equations of the local thresholds, and found that some threshold parameters can be put in relation with the prevailing lithology. In addition, we investigated the possible relations between effectiveness of the threshold and number of landslides used for the calibration. A validation procedure and a quantitative comparison with some literature thresholds showed that the performance of a threshold can be increased if the areal extent of its test area is reduced, as long as a statistically significant landslide sample is present. In particular, we demonstrated that the effectiveness of a warning system can be significantly enhanced if a mosaic of site-specific thresholds is used instead of a single regional threshold.

Segoni, S.; Rosi, A.; Rossi, G.; Catani, F.; Casagli, N.

2014-09-01

430

Floodplains of large river systems - homogenous or heterogeneous deposition environments? Lessons learned from high-resolution XS210Pb analyses  

NASA Astrophysics Data System (ADS)

One of the questions in fluvial geomorphology of large river basins is the question of how sediment is distributed on floodplains. For large rivers different processes and conveyors like floodplain channels, crevasse splays and avulsions play a role in sediment delivery to the floodplains. But how efficient and homogenous is sediment transport to floodplains in large river systems? How dependent is overbank sedimentation on external factors like climate and land cover change? How stable are sediments in distal parts of the floodplain after deposition? And, have short-term processes implications on the use of floodplain profiles as long-term records? Trying to answer some of these questions several landscape units along the Sacramento River floodplain between River Mile (RM) 175 and RM 195 have been analysed for infilling rates and processes using OSL and high-resolution XS210Pb profile analyses and dating. The landscape structure of this particular reach of the Sacramento River with large ephemeral floodplain channel systems, natural, large scale annual inundation of the floodplain and a high level of preservation of pristine fluvial environments is highly suited to answer the question of how different topographic units influence sediment deposition on a floodplain. Using high-resolution XS210Pb analyses it is possible not only to calculate infilling rates but also to identify different styles of infilling and erosion processes and their distribution over the floodplain of a large river system during the last century. Thus shedding light on the complexity of large river floodplains as sediment sinks. Using OSL and 14C dating as additional dating tools, this combined approach also enabled the comparison of last centuries' processes and rates with all-Holocene records testing how well modern sedimentation rates fit site specific long term evolution.

Will, Mathias; Aalto, Rolf; Fuchs, Markus

2013-04-01