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1

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

NASA Astrophysics Data System (ADS)

A RAMI (Reliability, Availability, Maintainability, Inspectability) analysis has been performed for the heating (& current drive) neutral beam (HNB) and diagnostic neutral beam (DNB) systems of the ITER device [1-3]. The objective of these analyses is to implement RAMI engineering requirements for design and testing to prepare a reliability-centred plan for commissioning, operation, and maintenance of the system in the framework of technical risk control to support the overall ITER Project. These RAMI requirements will correspond to the RAMI targets for the ITER project and the compensating provisions to reach them as deduced from the necessary actions to decrease the risk level of the function failure modes. The RAMI analyses results have to match with the procurement plan of the systems.

Chang, D. H.; Lee, S.; Hemsworth, R.; van Houtte, D.; Okayama, K.; Sagot, F.; Schunke, B.; Svensson, L.

2011-09-01

2

Design description and performance analyses of the European HCPB test blanket system in ITER feat  

Microsoft Academic Search

The helium cooled pebble bed (HCPB) blanket is one of the two European DEMO blanket concepts proposed for testing in international thermonuclear experimental reactor (ITER). The purpose of the tests is to validate the design principles and the operational feasibility for the demonstration blanket system. This includes the basic support functions like tritium extraction, helium cooling and heat transport, and

L. V Boccaccini; N Bekris; Y Chen; U Fischer; S Gordeev; S Hermsmeyer; E Hutter; K Kleefeldt; S Malang; K Schleisiek; I Schmuck; H Schnauder; H Tsige-Tamirat

2002-01-01

3

ITER cryogenic system  

Microsoft Academic Search

The main ITER cryogenic users are the superconducting magnets together with the 80K thermal shields. The key requirements that drive the design of the ITER cryogenic system are the intrinsically pulsed heat deposition in the magnets due to electromagnetic field and nuclear heating cyclic variations, and the usage of large flow capacity helium circulating pumps for forced-flow cooling of the

V. Kalinin; E. Tada; F. Millet; N. Shatil

2006-01-01

4

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

5

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

6

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

NASA Astrophysics Data System (ADS)

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

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

1993-06-01

7

Iterative marker excision system.  

PubMed

The deletions of large genomic DNA fragments and consecutive gene knockouts are prerequisites for the generation of organisms with improved properties. One of the key issues in this context is the removal of antibiotic resistance markers from engineered organisms without leaving an active recombinase recognition site. Here, we report the establishment of an iterative marker excision system (IMES) that solves this problem. Based on the phiC31 integrase and its mutant att sites, IMES can be used for highly effective deletion of DNA fragments between inversely oriented B-CC and P-GG sites. The B-CC and P-GG sites are derived from attB and attP by substitution of the central core TT dinucleotide with CC and GG, respectively. An unnatural RR site that resides in the chromosome following deletion is the joining product of the right shoulders of B-CC and P-GG. We show that the RR sites do not recombine with each other as well as the RR site recombines with B-CC. The recombination efficiencies between RR and P-GG or RR and LL are only 0.1 % and 1 %, respectively. Thus, IMES can be used for multistep genomic engineering without risking unwanted DNA recombination. The fabrication of multi-purpose antibiotic cassettes and examples of the utilisation of IMES are described. PMID:24473925

Myronovskyi, Maksym; Rosenkränzer, Birgit; Luzhetskyy, Andriy

2014-05-01

8

Electromagnetic Analyses of ITER Lower ELM Right Bottom Corner  

NASA Astrophysics Data System (ADS)

ELM (edge localized mode) coils are key components of ITER that suppress the edge localized mode phenomenon. A giant electromagnetic force is generated during normal operations by the current flowing in the ELM coils interacting with the external background field. The Lorentz force will induce Tresca stress in the ELM coils. If the load goes beyond the allowable threshold, the coils can hardly satisfy the safety requirements. The right-hand bottom corner was chosen to perform our electromagnetic analyses. Based on the Maxwell equation, the detailed magnetic field and Lorentz force were calculated. By use of the finite element software ANSYS, the Tresca stress was extracted and evaluated based on our analytical design. The present analysis aims to verify the feasibility of the current design. It can also serve as guidance for fabrication and structural optimization.

Wang, Xianwei; Xie, Fei; Jin, Huan

2014-08-01

9

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

10

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

11

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

12

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

SciTech Connect

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

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

1994-09-01

13

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

2010-05-31

14

Iterative design of video communication systems  

Microsoft Academic Search

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

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

1992-01-01

15

Development of pellet injection systems for ITER  

SciTech Connect

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

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

1995-12-31

16

Neutronics and thermal design analyses of US solid breeder blanket for ITER  

SciTech Connect

The US Solid Breeder Blanket is designed to produce the necessary tritium required for the ITER operation and to operate at power reactor conditions as much as possible. Safety, low tritium inventory, reliability, flexibility cost, and minimum R D requirements are the other design criteria. To satisfy these criteria, the produced tritium is recovered continuously during operation and the blanket coolant operates at low pressure. Beryllium multiplier material is used to control the solid-breeder temperature. Neutronics and thermal design analyses were performed in an integrated manner to define the blanket configuration. The reference parameters of ITER including the operating scenarios, the neutron wall loading distribution and the copper stabilizer are included in the design analyses. Several analyses were performed to study the impact of the reactor parameters, blanket dimensions, material characteristics, and heat transfer coefficient at the material interfaces on the blanket performance. The design analyses and the results from the different studies are summarized. 6 refs., 3 figs., 3 tabs.

Gohar, Y.; Billone, M.; Attaya, H. (Argonne National Lab., IL (USA)); Sawan, M. (Wisconsin Univ., Madison, WI (USA))

1990-09-01

17

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

18

Nuclear modules of ITER tokamak systems code  

Microsoft Academic Search

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

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

1987-01-01

19

Analysing Java System Properties Implementation  

E-print Network

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

Nierstrasz, Oscar

20

Status of ITER ICH Matching System Design  

SciTech Connect

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

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

2009-11-26

21

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

PubMed

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

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

2010-02-01

22

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

NASA Astrophysics Data System (ADS)

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

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

2010-02-01

23

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

SciTech Connect

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

Kashiwagi, M.; Taniguchi, M.; Dairaku, M.; Hanada, M.; Mizuno, T.; Tobari, H.; Umeda, N.; Watanabe, K.; Sakamoto, K.; Inoue, T. [Japan Atomic Energy Agency (JAEA), 801-1, Mukoyama, Naka 311-0193 (Japan); Grisham, L. R. [Princeton University, Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)

2010-02-15

24

The ITER blanket system design challenge  

NASA Astrophysics Data System (ADS)

This paper summarizes the latest progress in the ITER blanket system design as it proceeds through its final design phase with the Final Design Review planned for Spring 2013. The blanket design is constrained by demanding and sometime conflicting design and interface requirements from the plasma and systems such as the vacuum vessel, in-vessel coils and blanket manifolds. This represents a major design challenge, which is highlighted in this paper with examples of design solutions to accommodate some of the key interface and integration requirements.

Raffray, A. R.; Calcagno, B.; Chappuis, P.; Fu, Zhang; Furmanek, A.; Jiming, Chen; Kim, D.-H.; Khomiakov, S.; Labusov, A.; Martin, A.; Merola, M.; Mitteau, R.; Sadakov, S.; Ulrickson, M.; Zacchia, F.; Contributors from the Blanket Integrated Product Team

2014-03-01

25

Iterative methods for the numerical solution of linear systems  

E-print Network

was directed to the development of other iterative methods based on orthogonality of vectors for solvingIterative methods for the numerical solution of linear systems Maria Louka National. The objective of this dissertation is the design and analysis of iterative methods for the numerical solution

Kouroupetroglou, Georgios

26

Optimal iterative control of unknown nonlinear systems using neural networks  

Microsoft Academic Search

An optimal iterative controller of unknown nonlinear systems using neural networks is presented. Initially the multilayer feedforward neural network is trained to learn the forward dynamics of the plant off-line. Then the control law is derived by the optimal iterative method based on the neural network during each sampling interval. The optimal iterative controller predicts the feedforward control action, while

Wang Fuli; Li Mingzhong

1997-01-01

27

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

28

a Revised Iter EC System Baseline Design Proposal  

Microsoft Academic Search

The ITER EC system is in the process of being revised as a result of the ITER design review that occurred during 2007. This revision is introducing several modifications to the gyrotron and transmission line layout as well as identify several interface issues between the subsystems comprising the EC system. Each modification aims at improving the EC systems performance while

M. A. Henderson; B. Beckett; C. Darbos; N. Kobayashi; G. Saibene; F. Albajar; T. Bonicelli; S. Alberti; R. Chavan; D. Fasel; T. P. Goodman; I. Gr. Pagonakis; O. Sauter; S. Cirant; D. Farina; G. Ramponi; R. Heidinger; B. Piosczyk; M. Thumm; S. L. Rao; K. Kajiwara; K. Sakamoto; K. Takahashi; G. Denisov; T. Bigelow; D. Rasmussen

2009-01-01

29

Iterative multiuser detection techniques for CDMA systems  

E-print Network

previous iteration). For the information bns dt ~chinnel encoder mlerlea iy ubol iiiippcr spreader Sl iiiforiii itio bits d ch: net encode interleavcr symbol mapper li e'Icier + + channel te iiifoiiliailo lilts d chminel inlerlea er [ symbol... mapper detnterleaver SISO lecoder interleaver SISO multiuser dmnrerleaver SISO dec~a informauon bits dl interlcaver n(onnauon bile + detector dcintcrlca er S ISO dec wl interleavcr mformanon bits+ Fig. 1. Iterative receiver under coded...

Du, Xuechao

2002-01-01

30

Gas analyses of the first complete JET cryopump regeneration with ITER-like wall  

NASA Astrophysics Data System (ADS)

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 (i) residual deuterium on the panel which is very loosely related to the campaign, (ii) impurities like nitrogen which stick on the panel, and (iii) the ammonia production which can be observed by mass spectrometry.

Grünhagen Romanelli, S.; Brezinsek, S.; 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.; Yorkshades, J.; Contributors, JET-EFDA

2014-04-01

31

Conference on iterative methods for large linear systems  

SciTech Connect

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

Kincaid, D.R. [comp.

1988-12-01

32

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

33

Iterative least squares method for global positioning system  

NASA Astrophysics Data System (ADS)

The efficient implementation of positioning algorithms is investigated for Global Positioning System (GPS). In order to do the positioning, the pseudoranges between the receiver and the satellites are required. The most commonly used algorithm for position computation from pseudoranges is non-linear Least Squares (LS) method. Linearization is done to convert the non-linear system of equations into an iterative procedure, which requires the solution of a linear system of equations in each iteration, i.e. linear LS method is applied iteratively. CORDIC-based approximate rotations are used while computing the QR decomposition for solving the LS problem in each iteration. By choosing accuracy of the approximation, e.g. with a chosen number of optimal CORDIC angles per rotation, the LS computation can be simplified. The accuracy of the positioning results is compared for various numbers of required iterations and various approximation accuracies using real GPS data. The results show that very coarse approximations are sufficient for reasonable positioning accuracy. Therefore, the presented method reduces the computational complexity significantly and is highly suited for hardware implementation.

He, Y.; Bilgic, A.

2011-08-01

34

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

35

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

36

ABSOLUTE CONTINUITY FOR RANDOM ITERATED FUNCTION SYSTEMS WITH OVERLAPS  

Microsoft Academic Search

We consider linear iterated function systems with a random multiplicative\\u000aerror on the real line. Our system is $\\\\{x\\\\mapsto d_i + \\\\lambda_i Y\\u000ax\\\\}_{i=1}^m$, where $d_i\\\\in \\\\R$ and $\\\\lambda_i>0$ are fixed and $Y> 0$ is a\\u000arandom variable with an absolutely continuous distribution. The iterated maps\\u000aare applied randomly according to a stationary ergodic process, with the\\u000asequence of i.i.d.

K ´ AROLY SIMON YUVAL PERES; BORIS SOLOMYAK

2006-01-01

37

ITER diagnostic systems in development in Ioffe Institute  

SciTech Connect

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. [A.F.Ioffe Physical-Technical Institute of Russian Academy of Sciences, Politechnicheskaya 26, St. Petersburg, 194021 (Russian Federation)

2014-08-21

38

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

39

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

Microsoft Academic Search

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

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

1994-01-01

40

EE 581 Power Systems Admittance Matrix: Direct and Iterative solutions,  

E-print Network

EE 581 Power Systems Admittance Matrix: Direct and Iterative solutions, Sensitivity #12;Overview: I. Interchange two rows II. Multiply a row by a nonzero real number III. Replace a row by its sum with a multiple of another row #12;Chapter 6.1: Gaussian Elimination Solution for row two: #12;Chapter 6

Wedeward, Kevin

41

A lower hybrid current drive system for ITER  

Microsoft Academic Search

A 20 MW\\/5 GHz lower hybrid current drive (LHCD) system was initially due to be commissioned and used for the second mission of ITER, i.e. the Q = 5 steady state target. Though not part of the currently planned procurement phase, it is now under consideration for an earlier delivery. In this paper, both physics and technology conceptual designs are

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

2009-01-01

42

Iterative algorithms for large sparse linear systems on parallel computers  

NASA Technical Reports Server (NTRS)

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

Adams, L. M.

1982-01-01

43

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

44

Status of Europe's contribution to the ITER EC system  

NASA Astrophysics Data System (ADS)

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

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

2015-03-01

45

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

E-print Network

Partners at the end of this reporting period involves nuclear data production, and in particularAnnual 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

46

Aviation System Analysis Capability Executive Assistant Analyses  

NASA Technical Reports Server (NTRS)

This document describes the analyses that may be incorporated into the Aviation System Analysis Capability Executive Assistant. The document will be used as a discussion tool to enable NASA and other integrated aviation system entities to evaluate, discuss, and prioritize analyses.

Roberts, Eileen; Kostiuk, Peter

1999-01-01

47

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

48

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...

49

Comparison of iterative wavefront reconstruction algorithms for high-resolution adaptive optics systems  

NASA Astrophysics Data System (ADS)

Based on a 979-actuator adaptive optics system, this paper analyzes the different performance of iterative wavefront reconstruction algorithms. Under the condition of dynamic wavefront errors, the iteration number, storage space and the number of multiplication of steepest descent method, conjugate gradient method and G-S iterative method are studied. The steepest descent method and conjugate gradient method need smaller storage space. Both the G-S iterative method and the conjugate gradient method converge faster than steepest descent method, while the latter takes the least number of multiplication. Finally, the optimal iterative algorithm is selected considering storage space, iteration numbers and the number of multiplication.

Cheng, Shengyi; Dong, Lizhi; Chen, Shanqiu; Yang, Ping; Ao, Mingwu; Xu, Bing

2014-11-01

50

Operation mode studies of the ITER cryodistribution system  

NASA Astrophysics Data System (ADS)

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

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

2012-06-01

51

Analysis of the ITER LFS Reflectometer Transmission Line System  

SciTech Connect

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

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

2010-01-01

52

In-vessel design of ITER diagnostic neutron activation system.  

PubMed

A neutron activation system utilizing an encapsulated metal sample technique will be implemented to evaluate total fusion power from ITER plasma. The positions of seven irradiation ends for each poloidal section are determined to optimize the measurements from asymmetric, elongated plasma with minimum uncertainty. To determine the exact location of the irradiation end, some physical and technical aspects for each location are investigated. Monte Carlo neutronic calculations are performed to assess the physical characteristics and optimize the design of each irradiation end. PMID:19044490

Cheon, M S; Pak, S; Lee, H G; Bertalot, L; Walker, C

2008-10-01

53

Polychromator for the edge Thomson scattering system in ITER.  

PubMed

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

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

2012-10-01

54

The efficient parallel iterative solution of large sparse linear systems  

SciTech Connect

The development of efficient, general-purpose software for the iterative solution of sparse linear systems on a parallel MIMD computer requires an interesting combination of expertise. Parallel graph heuristics, convergence analysis, and basic linear algebra implementation issues must all be considered. In this paper, we discuss how we have incorporated recent results in these areas into a general-purpose iterative solver. First, we consider two recently developed parallel graph coloring heuristics. We show how the method proposed by Luby, based on determining maximal independent sets, can be modified to run in an asynchronous manner and give aa expected running time bound for this modified heuristic. In addition, a number of graph reduction heuristics are described that are used in our implementation to improve the individual processor performance. The effect of these various graph reductions on the solution of sparse triangular systems is categorized. Finally, we discuss the performance of this solver from the perspective of two large-scale applications: a piezoelectric crystal finite-element modeling problem, and a nonlinear optimization problem to determine the minimum energy configuration of a three-dimensional, layered superconductor model.

Jones, M.T.; Plassmann, P.E.

1992-06-01

55

Policy iteration optimal tracking control for chaotic systems by using an adaptive dynamic programming approach  

NASA Astrophysics Data System (ADS)

A policy iteration algorithm of adaptive dynamic programming (ADP) is developed to solve the optimal tracking control for a class of discrete-time chaotic systems. By system transformations, the optimal tracking problem is transformed into an optimal regulation one. The policy iteration algorithm for discrete-time chaotic systems is first described. Then, the convergence and admissibility properties of the developed policy iteration algorithm are presented, which show that the transformed chaotic system can be stabilized under an arbitrary iterative control law and the iterative performance index function simultaneously converges to the optimum. By implementing the policy iteration algorithm via neural networks, the developed optimal tracking control scheme for chaotic systems is verified by a simulation. Project supported by the National Natural Science Foundation of China (Grant Nos. 61034002, 61233001, 61273140, 61304086, and 61374105) and the Beijing Natural Science Foundation, China (Grant No. 4132078).

Wei, Qing-Lai; Liu, De-Rong; Xu, Yan-Cai

2015-03-01

56

Iterative Development of Visual Control Systems in a Research Vivarium  

PubMed Central

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

57

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

58

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

59

Iterative Repair Planning for Spacecraft Operations Using the Aspen System  

NASA Technical Reports Server (NTRS)

This paper describes the Automated Scheduling and Planning Environment (ASPEN). ASPEN encodes complex spacecraft knowledge of operability constraints, flight rules, spacecraft hardware, science experiments and operations procedures to allow for automated generation of low level spacecraft sequences. Using a technique called iterative repair, ASPEN classifies constraint violations (i.e., conflicts) and attempts to repair each by performing a planning or scheduling operation. It must reason about which conflict to resolve first and what repair method to try for the given conflict. ASPEN is currently being utilized in the development of automated planner/scheduler systems for several spacecraft, including the UFO-1 naval communications satellite and the Citizen Explorer (CX1) satellite, as well as for planetary rover operations and antenna ground systems automation. This paper focuses on the algorithm and search strategies employed by ASPEN to resolve spacecraft operations constraints, as well as the data structures for representing these constraints.

Rabideau, G.; Knight, R.; Chien, S.; Fukunaga, A.; Govindjee, A.

2000-01-01

60

AUTOMATED SYSTEM FOR DATA MEASURING AND ANALYSES FROM EMBEDDED SYSTEMS  

Microsoft Academic Search

This paper presents the design of an automated system for signal processing in embedded systems. The design is worked out for an automatic predictive diagnostic system use. This automated system allows communication with embedded systems, an embedded systems control, a data collection from sensors, various signal analyses, and react to limits transcendence. Additionally, the developed system contains a transparent program

ZDENEK MACHACEK; VILEM SROVNAL

61

Dynamic Performance of the ITER Reactive Power Compensation System  

NASA Astrophysics Data System (ADS)

Dynamic performance of a reactive power compensation (RPC) system for the international thermonuclear experimental reactor (ITER) power supply is presented. Static var compensators (SVCs) are adopted to mitigate voltage fluctuation and reduce the reactive power down to a level acceptable for the French/European 400 kV grid. A voltage feedback and load power feedforward controller for SVC is proposed, with the feedforward loop intended to guarantee short response time and the feedback loop ensuring good dynamics and steady characteristics of SVC. A mean filter was chosen to measure the control signals to improve the dynamic response. The dynamic performance of the SVC is verified by simulations using PSCAD/EMTDC codes.

Sheng, Zhicai; Fu, Peng; Xu, Liuwei

2011-10-01

62

Annual Report of the EURATOM/CCFE Fusion Programme 2013 8 ITER SYSTEMS  

E-print Network

Annual Report of the EURATOM/CCFE Fusion Programme 2013 8.1 8 ITER SYSTEMS 8 ITER SYSTEMS 8.1 the year with the successful preliminary design review (PDR) of the Faraday Screen Bars (Fig 8.1). A fourth waste analysis, diagnostic windows, remote handling, operating scenarios, magnetics analysis and de

63

Iterative Solution of Dense Linear Systems Jussi Rahola  

E-print Network

. In this work, the application of iterative solvers for three prob­ lems involving integral equations has been from integral equations is as follows: ffl Choose an iterative solver ffl Choose a preconditioner av. G. Coriolis, 31057 Toulouse Cedex, France Abstract Integral equation methods have been used

64

Design modification and optimization of the ITER cooling water system  

Microsoft Academic Search

ITER (Latin for “the way”), the largest fusion experimental reactor in the world, is designed to demonstrate the technological feasibility of nuclear fusion energy conversion, at plant scale, from high temperature deuterium–tritium plasma using the Tokamak magnetic confinement arrangement.ITER will have a large vacuum vessel that hosts the plasma facing components. These components include the blanket and the divertor that

G. Dell’Orco; W. Curd; J. Berry; K. P. Chang; J. Ferrada; B. Gopalapillai; D. Gupta; S. Kim; I. Kuehn; A. Kumar; F. Li; A. Petrov; W. Reiersen

2011-01-01

65

Used Fuel Management System Interface Analyses - 13578  

SciTech Connect

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

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

2013-07-01

66

An Iterative Method for Carrier Frequency Offset Estimation in OFDM Systems via Scattered Pilots  

Microsoft Academic Search

The paper proposes a new iterative method to estimate the carrier frequency offset (CFO) with scattered pilot symbols inserted for channel estimation in orthogonal frequency division multiplexing (OFDM) systems. Assuming that the channel remains constant during a few consecutive OFDM blocks, the new method uses the correlations of the pilot symbols in these consecutive OFDM blocks. And an iterative concept

Lin Bai; Qinye Yin

2010-01-01

67

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

Microsoft Academic Search

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

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

2007-01-01

68

On the Number of Rational Iterated Pre-images of the Origin Under Quadratic Dynamical Systems  

Microsoft Academic Search

For a quadratic endomorphism of the affine line defined over the rationals, we consider the problem of bounding the number of rational points that eventually land at the origin after iteration. In the article ``Uniform Bounds on Pre-Images Under Quadratic Dynamical Systems,'' by two of the present authors and five others, it was shown that the number of rational iterated

Xander Faber; Benjamin Hutz; Michael Stoll

2008-01-01

69

Policy iteration adaptive dynamic programming algorithm for discrete-time nonlinear systems.  

PubMed

This paper is concerned with a new discrete-time policy iteration adaptive dynamic programming (ADP) method for solving the infinite horizon optimal control problem of nonlinear systems. The idea is to use an iterative ADP technique to obtain the iterative control law, which optimizes the iterative performance index function. The main contribution of this paper is to analyze the convergence and stability properties of policy iteration method for discrete-time nonlinear systems for the first time. It shows that the iterative performance index function is nonincreasingly convergent to the optimal solution of the Hamilton-Jacobi-Bellman equation. It is also proven that any of the iterative control laws can stabilize the nonlinear systems. Neural networks are used to approximate the performance index function and compute the optimal control law, respectively, for facilitating the implementation of the iterative ADP algorithm, where the convergence of the weight matrices is analyzed. Finally, the numerical results and analysis are presented to illustrate the performance of the developed method. PMID:24807455

Liu, Derong; Wei, Qinglai

2014-03-01

70

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

NASA Astrophysics Data System (ADS)

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

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

2009-06-01

71

System for analysing sickness absenteeism in Poland.  

PubMed

The National System of Sickness Absenteeism Statistics has been functioning in Poland since 1977, as the part of the national health statistics. The system is based on a 15-percent random sample of copies of certificates of temporary incapacity for work issued by all health care units and authorised private medical practitioners. A certificate of temporary incapacity for work is received by every insured employee who is compelled to stop working due to sickness, accident, or due to the necessity to care for a sick member of his/her family. The certificate is required on the first day of sickness. Analyses of disease- and accident-related sickness absenteeism carried out each year in Poland within the statistical system lead to the main conclusions: 1. Diseases of the musculoskeletal and peripheral nervous systems accounting, when combined, for 1/3 of the total sickness absenteeism, are a major health problem of the working population in Poland. During the past five years, incapacity for work caused by these diseases in males increased 2.5 times. 2. Circulatory diseases, and arterial hypertension and ischaemic heart disease in particular (41% and 27% of sickness days, respectively), create an essential health problem among males at productive age, especially, in the 40 and older age group. Absenteeism due to these diseases has increased in males more than two times. PMID:9278128

Indulski, J A; Szubert, Z

1997-01-01

72

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

73

Active spectroscopic measurements using the ITER diagnostic system.  

PubMed

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 (?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. PMID:21033918

Thomas, D M; Counsell, G; Johnson, D; Vasu, P; Zvonkov, A

2010-10-01

74

Iterative Repair Planning for Spacecraft Operations Using the ASPEN System  

Microsoft Academic Search

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

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

1999-01-01

75

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

SciTech Connect

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

Slack, D.S.

1991-09-25

76

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

77

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

78

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

79

AN ITERATIVE METHOD FOR SOLVING COMPLEX-SYMMETRIC SYSTEMS ARISING IN ELECTRICAL POWER MODELING  

Microsoft Academic Search

We propose an iterative method for solving a complex-symmetric linear system arising in electric power networks. Our method extends Gremban, Miller, and Zagha's (in Proceedings of the International Parallel Processing Symposium, IEEE Computer Society, Los Alamitos, CA, 1995) support-tree preconditioner to handle complex weights and vastly different admittances. Our underlying iteration is a modification to transpose-free QMR (6) to enhance

VICTORIA E. HOWLE; STEPHEN A. VAVASIS

2000-01-01

80

Neural network based iterative learning predictive control design for mechatronic systems with isolated nonlinearity  

Microsoft Academic Search

The paper presents a new nonlinear predictive control design for a kind of nonlinear mechatronic drive systems, which leads to the improvement of regulatory capacity for both reference input tracking and load disturbance rejection. The nonlinear system is first treated into an equal linear time-variant system plus a nonlinear part using a neural network, then an iterative learning linear predictive

Ridong Zhang; Anke Xue; Jianzhong Wang; Shuqing Wang; Zhengyun Ren

2009-01-01

81

USING ITERATIVE DESIGN AND DEVELOPMENT FOR MOBILE LEARNING SYSTEMS IN SCHOOL PROJECTS  

Microsoft Academic Search

Different approaches have been proposed on the use of digital and interactive technology in mobile learning contexts. In line with recent findings in the literature, we suggest that mobile learning systems benefit from an iterative design and development process within a holistic, socio-technical system view. This system view makes allowance for the complex dynamics between teachers, students, researchers, the multiplicity

André Melzer; Lia Hadley; Marie Glasemann; Simon Werner; Thomas Winkler; Michael Herczeg

82

Recommendations for a cryogenic system for ITER (International Thermonuclear Experimental Reactor)  

SciTech Connect

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Soviet Union, and the United States. ITER will be a large machine requiring up to 100 kW of refrigeration at 4.5 K to cool its superconducting magnets. Unlike earlier fusion experiments, the ITER cryogenic system must handle pulse loads constituting a large percentage of the total load. These come from neutron heating during a fusion burn and from ac losses during ramping of current in the PF (poloidal field) coils. This paper presents a conceptual design for a cryogenic system that meets ITER requirements. It describes a system with the following features: Only time-proven components are used. The system obtains a high efficiency without use of cold pumps or other developmental components. High reliability is achieved by paralleling compressors and expanders and by using adequate isolation valving. The problem of load fluctuations is solved by a simple load-leveling device. The cryogenic system can be housed in a separate building located at a considerable distance from the ITER core, if desired. The paper also summarizes physical plant size, cost estimates, and means of handling vented helium during magnet quench. 4 refs., 4 figs., 3 tabs.

Slack, D.S.

1989-09-20

83

Mapping optimization for space-time block coded OFDM systems with iterative decoding  

Microsoft Academic Search

An iterative detection scheme enhances the performance of bit-interleaved coded modulation (BICM) by exploiting frequency diversity gains. Additionally, space-time block coding (STBC) scheme can significantly improve the system performance in fading channels by proper coordinating of the signaling over multiple antennas. In this paper, STBC technique based on BICM is applied to orthogonal frequency division multiplexing (OFDM) system over frequency

Jinsoo Choi; Wookbong Lee; Inkyu Lee

2005-01-01

84

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

ERIC Educational Resources Information Center

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

Lofton, Glenda G.; And Others

85

Cross-coupled iterative learning control of systems with dissimilar dynamics: design and implementation  

Microsoft Academic Search

Cross-coupled iterative learning control has previously been applied to contour tracking problems with planar manufacturing robots in which both axes can be characterised as similar systems; having similar dynamics and identical hardware. However, there are many repetitive applications in which dynamically dissimilar systems cooperate to pursue a primary performance objective. This article introduces a novel framework to couple dynamically dissimilar

Kira L. Barton; David J. Hoelzle; Andrew G. Alleyne; Amy J. Wagoner Johnson

2010-01-01

86

Cross-coupled iterative learning control of systems with dissimilar dynamics: design and implementation  

Microsoft Academic Search

Cross-coupled iterative learning control has previously been applied to contour tracking problems with planar manufacturing robots in which both axes can be characterised as similar systems; having similar dynamics and identical hardware. However, there are many repetitive applications in which dynamically dissimilar systems cooperate to pursue a primary performance objective. This article introduces a novel framework to couple dynamically dissimilar

Kira L. Barton; David J. Hoelzle; Andrew G. Alleyne; Amy J. Wagoner Johnson

2011-01-01

87

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

E-print Network

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

Bagnasco, M; Bessette, D; Marinucci, C

2010-01-01

88

Sprinkler System Installer. Occupational Analyses Series.  

ERIC Educational Resources Information Center

This analysis covers tasks performed by a sprinkler system installer, an occupational title some provinces and territories of Canada have also identified as pipefitter--fire protection mechanic specialty; sprinkler and fire protection installer; sprinkler and fire protection systems installer; and sprinkler fitter. A guide to analysis discusses…

Chinien, Chris; Boutin, France

89

Systems Analyses of Advanced Brayton Cycles  

Microsoft Academic Search

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

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

2008-01-01

90

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

91

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

92

ITER in-vessel system design and performance  

NASA Astrophysics Data System (ADS)

The article reviews the design and performance of the in-vessel components of ITER as developed for the Engineering Design Activities (EDA) Final Design Report. The double walled vacuum vessel is the first confinement boundary and is designed to maintain its integrity under all normal and off-normal conditions, e.g. the most intense vertical displacement events (VDEs) and seismic events. The shielding blanket consists of modules connected to a toroidal backplate by flexible connectors which allow differential displacements due to temperature non-uniformities. Breeding blanket modules replace the shield modules for the Enhanced Performance Phase. The divertor concept is based on a cassette structure which is convenient for remote installation and removal. High heat flux (HHF) components are mechanically attached and can be removed and replaced in the hot cell. Operation of the divertor is based on achieving partially detached plasma conditions along and near the separatrix. Nominal heat loads of 5-10 MW/m2 are expected on the target. These are accommodated by HHF technology developed during the EDA. Disruptions and VDEs can lead to melting of the first wall armour but no damage to the underlying structure. Stresses in the main structural components remain within allowable ranges for all postulated disruption and seismic events.

Parker, R. R.

2000-03-01

93

Iterative phase noise estimation and suppression for CO-OFDM systems with large laser linewidth  

NASA Astrophysics Data System (ADS)

In order to further improve the laser phase noise tolerance of coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems, an iterative phase noise suppression algorithm is proposed in this paper, which is powerful in mitigating the laser phase noise induced intercarrier interference (ICI) even when laser linewidth achieves 2 MHz. Compared with the existing ICI suppression method, the performance gain brought by the proposal is significant when the laser linewidth is larger than 1.5 MHz. The BER floor which can not be avoided by using the existing phase noise suppression methods can be reduced effectively by employing the new iterative algorithm.

Yang, Chuanchuan; He, Changhong; Wang, Ziyu

2011-12-01

94

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

SciTech Connect

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

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

1995-12-31

95

ITER have a need for ion cyclotron heating (ICH) as part of the plasma heating system mix to reach the  

E-print Network

Background ITER have a need for ion cyclotron heating (ICH) as part of the plasma heating system ITER ion cyclotron heating systems design Section view through antenna module Thermal model of antenna The ion cyclotron heating antenna is currently in its preliminary design phase and is undergoing detailed

96

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

97

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

98

A design proposal for the ITER ion cyclotron H&CD system  

Microsoft Academic Search

In ITER, the ion cyclotron heating (ICH) system should routinely and reliably operate at a power level close to the installed power (20 MW) in quasi-continuous operation. The operation will be efficient and reliable only if plasma coupling and absorption of the fast wave on the plasma bulk are optimized, parasitic power losses in the plasma edge minimized, and the

G. Bosia; B. Beaumont; S. Bremond; K. Vulliez

2006-01-01

99

Annual Report of the EURATOM/CCFE Fusion Programme 2010/11 8 ITER Systems  

E-print Network

), the European domestic agency, which has to deliver the European `in-kind' contributions to ITER, and is based in collisions with plasma ions and electrons, thus heating the plasma. A consortium of five European by space and engineering issues; · Contributing to discussions on grounding and reflectometry systems

100

The European test blanket module systems: Design and integration in ITER  

Microsoft Academic Search

The European Union proposes two different concepts of helium-cooled blanket for testing in ITER, one with ceramic breeder and beryllium, the second with lithium lead as breeder and multiplier. Test blanket modules (TBM) for both blanket concepts and their auxiliary systems have being designed in the last 2 years; this paper presents the status of this work as reached in

L. V. Boccaccini; J.-F. Salavy; R. Lässer; A. Li Puma; R. Meyder; H. Neuberger; Y. Poitevin; G. Rampal

2006-01-01

101

Combined Feedback Control and Iterative Learning Control Design With Application to Nanopositioning Systems  

Microsoft Academic Search

This paper examines a coordinated feedback and feedforward control design strategy for precision motion control (PMC) systems. It is assumed that the primary exogenous signals are repeated; including disturbances and references. Therefore, an iterative learning control (ILC) feedforward strategy can be used. The introduction of additional non-repeating exogenous signals, including disturbances, noise, and reset errors, necessitates the proper coordination between

Brian E. Helfrich; Chibum Lee; Douglas A. Bristow; X. H. Xiao; Jingyan Dong; A. G. Alleyne; Srinivasa M Salapaka; Placid M. Ferreira

2010-01-01

102

NUCLEAR MODULES OF ITER TOKAMAK SYSTEMS CODE* ain CONF-871007--68  

E-print Network

37830 Abstract Nuclear modules were developed to model various reactor components In the ITER systems code.' These modules include first wall, tritium breeding blanket (or shield), bulk snield, reactor parameters for each component as a function of the reactor operating conditions. Several design options

Harilal, S. S.

103

An overview of the ITER electron cyclotron H&CD system  

Microsoft Academic Search

This paper reviews the design and functionality of the 24 MW 170 GHz electron cyclotron heating and current drive system being planned for the ITER Tokamak. The sub-systems (power supplies, gyrotrons, transmission lines and launcher antennas) are described based on present day technologies, while on-going R&D provides component and sub-system testing with the possibility of increasing the reliability of the

M. Henderson; F. Albajar; S. Alberti; U. Baruah; T. Bigelow; B. Becket; R. Bertizzolo; T. Bonicelli; A. Bruschi; J. Caughman; R. Chavan; S. Cirant; A. Collazos; C. Darbos; M. de Baar; G. Denisov; D. Farina; F. Gandini; T. Gassman; T. P. Goodman; R. Heidinger; J. P. Hogge; O. Jean; K. Kajiwara; W. Kasparek; A. Kasugai; S. Kern; N. Kobayashi; J. D. Landis; A. Moro; C. Nazare; J. Oda; I. Paganakis; P. Platania; B. Plaum; E. Poli; L. Porte; B. Piosczyk; G. Ramponi; S. L. Rao; D. Rasmussen; D. Ronden; G. Saibene; K. Sakamoto; F. Sanchez; T. Scherer; M. Shapiro; C. Sozzi; P. Spaeh; D. Straus; O. Sauter; K. Takahashi; A. Tanga; R. Temkin; M. Thumm; M. Q. Tran; H. Zohm; C. Zucca

2009-01-01

104

iterative solution of augmented systems arising in interior methods  

E-print Network

solution of a symmetric indefinite linear system of equations known as the KKT system. .... to solve KKT systems are (i) termination control, (ii) inertia control, and (iii) inherent ill-conditioning. ...... problems will be the subject of a follow-up paper.

2005-09-04

105

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

106

Twin-Screw Extruder Development for the ITER Pellet Injection System  

SciTech Connect

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

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

2009-01-01

107

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

Microsoft Academic Search

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

Tsung-Ying Lee

2008-01-01

108

Iterative Joint Channel Estimation and Multiuser Detection for Wireless MIMO-OFDM Systems: Performance in a Real Indoor Scenario  

Microsoft Academic Search

An iterative receiver for multiple-input multiple- output (MIMO) orthogonal frequency division multiplexing (OFDM) wireless systems is presented and tested on channel measurements from a real indoor scenario. The receiver jointly performs channel estimation and multiuser detection, with soft information iteratively provided by the singleuser decoders. Results for the performance are presented in terms of bit error rate (BER) and relative

Pierluigi Salvo Rossi; Parisa Pakniat; R. R. Muller; Ove Edfors

2007-01-01

109

A model-free robust policy iteration algorithm for optimal control of nonlinear systems  

Microsoft Academic Search

An online model-free solution is developed for the infinite-horizon optimal control problem for continuous-time nonlinear systems. A novel actor-critic-identifier (ACI) structure is used to implement the Policy Iteration algorithm, wherein two neural network structures are used - a robust dynamic neural network (DNN) to asymptotically identify the uncertain system with additive disturbances, and a critic NN to approximate the value

Shubhendu Bhasin; Marcus Johnson; Warren E. Dixon

2010-01-01

110

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

111

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

112

ITERATIVE ALGEBRAS: HOW ITERATIVE ARE THEY?  

Microsoft Academic Search

Iterative algebras, defined by the property that every guarded system of recursive equations has a unique solution, are proved to have a much stronger property: every system of recursive equations has a unique strict solution. Those systems that have a unique solution in every iterative algebra are characterized.

J. AD ´; S. MILIUS; J. VELEBIL

2008-01-01

113

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...

114

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

115

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

SciTech Connect

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

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

1997-04-01

116

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

117

Iterative correlation-based controller tuning with application to a magnetic suspension system  

Microsoft Academic Search

Iterative tuning of the parameters of a restricted-order controller using the data acquired in closed-loop operation seems to be a promising idea, especially for tuning PID controllers in industrial applications. In this paper, a new tuning approach based on decorrelation is proposed. The basic idea is to make the output error between the designed and achieved closed-loop systems uncorrelated with

A. Karimi; L. Miškovi?; D. Bonvin

2003-01-01

118

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

119

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

Microsoft Academic Search

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

M. L. Wilson; R. W. Barnard; J. H. Gauthier

1994-01-01

120

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

121

Catastrophic Failures in Power Systems: Causes, Analyses, and Countermeasures  

Microsoft Academic Search

Catastrophic failures of power systems are phenomena which occur with some regularity throughout the world. It is recognized that these cannot be prevented, although with the use of newer developments in power engineering, in communication systems, and in computer engineering it would be possible to reduce their frequency and their impact on society. Analyses of many blackouts point to some

JAIME DE LA REE; Yilu Liu; LAMINE MILI; ARUN G. PHADKE; LUIZ DASILVA

2005-01-01

122

Coherence: An Approach to Representing Ethnographic Analyses in Systems Design  

Microsoft Academic Search

This paper is concerned with how to represent in system design the kinds of features of work settings as reported by ethnographic studies of work. Various researchers and practitioners have found that ethnomethodological analyses of work settings can provide useful insights to the work processes and settings that system design is interested in. Previously at Lancaster, we have examined ways

Stephen Viller; Ian Sommerville

1999-01-01

123

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

124

Analysis of the ITER low field side reflectometer transmission line system.  

PubMed

A critical issue in the design of the ITER low field side reflectometer is the transmission line (TL) system. A TL connects each launcher to a diagnostic instrument. Each TL will typically consist of ?42?m of corrugated waveguide and up to ten miter bends. Important issues for the performance of the TL system are mode conversion and reflections. Minimizing these issues are critical to minimizing standing waves and phase errors. The performance of TL system is analyzed and recommendations are given. PMID:21033952

Hanson, G R; Wilgen, J B; Bigelow, T S; Diem, S J; Biewer, T M

2010-10-01

125

A design proposal for the ITER ion cyclotron H&CD system  

NASA Astrophysics Data System (ADS)

In ITER, the ion cyclotron heating (ICH) system should routinely and reliably operate at a power level close to the installed power (20 MW) in quasi-continuous operation. The operation will be efficient and reliable only if plasma coupling and absorption of the fast wave on the plasma bulk are optimized, parasitic power losses in the plasma edge minimized, and the RF power flow, from the wave launching structure to the absorption layer, efficiently maintained against the effects of significant load variations. In this paper the ion cyclotron launcher proposed in the ITER Final Design Report (FDR) is briefly reviewed and a number of design changes are proposed, without any modification of the basic layout, in order to simplify construction and maintenance and to improve the performance and reliability of operation.

Bosia, G.; Beaumont, B.; Bremond, S.; Vulliez, K.

2006-07-01

126

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

127

System-specific static code analyses: a case study in the complex embedded systems domain  

Microsoft Academic Search

In this paper, we are exploring the approach to utilize system-specific static analyses of code with the goal to improve software\\u000a quality for specific software systems. Specialized analyses, tailored for a particular system, make it possible to take advantage\\u000a of system\\/domain knowledge that is not available to more generic analyses. Furthermore, analyses can be selected and\\/or developed\\u000a in order to

Holger M. KienleJohan; Johan Kraft; Thomas Nolte

128

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

129

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

2005-10-04

130

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

SciTech Connect

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

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

2009-11-26

131

Design and Analysis of the Main AC/DC Converter System for ITER  

NASA Astrophysics Data System (ADS)

A design of the main AC/DC converter system for ITER is described and the configuration of the main AC/DC converters is presented. To reduce the reactive power absorbed from the converter units, the main AC/DC converters are designed to be series-connected and work in a sequential mode. The structure of the regulator of the converter system is described. A simulation model was built up for the PSCAD/EMTDC code, and the design was validated accordingly. Harmonic analysis and reactive power calculation of the converters units are presented. The results reveal the advantage of sequential control in reducing reactive power and harmonics.

Sheng, Zhicai; Xu, Liuwei; Fu, Peng

2012-04-01

132

The targeted heating and current drive applications for the ITER electron cyclotron system  

NASA Astrophysics Data System (ADS)

A 24 MW Electron Cyclotron (EC) system operating at 170 GHz and 3600 s pulse length is to be installed on ITER. The EC plant shall deliver 20 MW of this power to the plasma for Heating and Current Drive (H&CD) applications. The EC system is designed for plasma initiation, central heating, current drive, current profile tailoring, and Magneto-hydrodynamic control (in particular, sawteeth and Neo-classical Tearing Mode) in the flat-top phase of the plasma. A preliminary design review was performed in 2012, which identified a need for extended application of the EC system to the plasma ramp-up, flattop, and ramp down phases of ITER plasma pulse. The various functionalities are prioritized based on those applications, which can be uniquely addressed with the EC system in contrast to other H&CD systems. An initial attempt has been developed at prioritizing the allocated H&CD applications for the three scenarios envisioned: ELMy H-mode (15 MA), Hybrid (˜12 MA), and Advanced (˜9 MA) scenarios. This leads to the finalization of the design requirements for the EC sub-systems.

Henderson, M.; Saibene, G.; Darbos, C.; Farina, D.; Figini, L.; Gagliardi, M.; Gandini, F.; Gassmann, T.; Hanson, G.; Loarte, A.; Omori, T.; Poli, E.; Purohit, D.; Takahashi, K.

2015-02-01

133

X-34 Main Propulsion System-Selected Subsystem Analyses  

NASA Technical Reports Server (NTRS)

The X-34 hypersonic flight vehicle is currently under development by Orbital Sciences Corporation (Orbital). The Main Propulsion System (MPS) has been designed around the liquid propellant Fastrac rocket engine currently under development at NASA Marshall Space Flight Center. This paper presents selected analyses of MPS subsystems and components. Topics include the integration of component and system level modeling of the LOX dump subsystem and a simple terminal bubble velocity analysis conducted to guide propellant feed line design.

Brown, T. M.; McDonald, J. P.; Knight, K. C.; Champion, R. H., Jr.

1998-01-01

134

An Iterative Method for Constructing Equilibrium Phase Models of Stellar Systems  

E-print Network

We present a new method for constructing equilibrium phase models for stellar systems, which we call the iterative method. It relies on constrained, or guided evolution, so that the equilibrium solution has a number of desired parameters and/or constraints. This method is very powerful, to a large extent due to its simplicity. It can be used for mass distributions with an arbitrary geometry and a large variety of kinematical constraints. We present several examples illustrating it. Applications of this method include the creation of initial conditions for N-body simulations and the modelling of galaxies from their photometric and kinematic observations.

S. A. Rodionov; E. Athanassoula; N. Ya Sotnikova

2008-10-22

135

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

NASA Astrophysics Data System (ADS)

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

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

2012-06-01

136

Iterative receivers for OFDM systems with dispersive fading and frequency offset  

E-print Network

OF SCIENCE Approved as to style and content by: Xiaodong Wang (Co-Chair of Committee) Zixiang Xiong (Co-Chair of Committee) Erchin Serpedin (Member) Garng M.Huang (Member) Jyh-Charn(Steve) Liu (Member) Chanan Singh (Head of Department) May 2003 Major Subject...: Electrical Engineering iii ABSTRACT Iterative Receivers for OFDM Systems with Dispersive Fading and Frequency O set. (May 2003) Hui Liu, B.S., Tsinghua University Co{Chairs of Advisory Committee: Dr. Xiaodong Wang Dr. Zixiang Xiong The presence of dispersive...

Liu, Hui

2004-09-30

137

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

138

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

139

Low-bit rate feedback strategies for iterative IA-precoded MIMO-OFDM-based systems.  

PubMed

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

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

2014-01-01

140

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

141

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

142

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

SciTech Connect

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

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

2009-07-01

143

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

PubMed Central

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

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

2014-01-01

144

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

145

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. PMID:25419094

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

2014-01-01

146

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

PubMed

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

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

2015-01-01

147

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

NASA Astrophysics Data System (ADS)

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

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

2015-01-01

148

Iterative solutions to the steady state density matrix for optomechanical systems  

E-print Network

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

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

2014-11-17

149

Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems  

SciTech Connect

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

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

2013-01-01

150

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

151

Multi-Element Unstructured Analyses of Complex Valve Systems  

NASA Technical Reports Server (NTRS)

The safe and reliable operation of high pressure test stands for rocket engine and component testing places an increased emphasis on the performance of control valves and flow metering devices. In this paper, we will present a series of high fidelity computational analyses of systems ranging from cryogenic control valves and pressure regulator systems to cavitating venturis that are used to support rocket engine and component testing at NASA Stennis Space Center. A generalized multi-element framework with sub-models for grid adaption, grid movement and multi-phase flow dynamics has been used to carry out the simulations. Such a framework provides the flexibility of resolving the structural and functional complexities that are typically associated with valve-based high pressure feed systems and have been difficult to deal with traditional CFD methods. Our simulations revealed a rich variety of flow phenomena such as secondary flow patterns, hydrodynamic instabilities, fluctuating vapor pockets etc. In the paper, we will discuss performance losses related to cryogenic control valves, and provide insight into the physics of the dominant multi-phase fluid transport phenomena that are responsible for the choking like behavior in cryogenic control elements. Additionally, we will provide detailed analyses of the modal instability that is observed in the operation of the dome pressure regulator valve. Such instabilities are usually not localized and manifest themselves as a system wide phenomena leading to an undesirable chatter at high flow conditions.

Sulyma, Peter (Technical Monitor); Ahuja, Vineet; Hosangadi, Ashvin; Shipman, Jeremy

2004-01-01

152

Dual-laser calibration of Thomson scattering systems in ITER and RFX-mod  

NASA Astrophysics Data System (ADS)

We first review the principles of the dual-laser calibration technique for measuring the relative sensitivities of the spectral channels in a Thomson scattering (TS) diagnostic system by detecting with the same spectrometer the spectra scattered by the same plasma volume from two laser pulses of different wavelengths. A new data analysis method is then introduced, based on the minimization of a single ?2 function, that provides a simpler and more convenient way to determine the measurement errors on the calibration coefficients. The new analysis method is used here to investigate the expected performances of this calibration technique in the core LIDAR TS system of ITER currently under design and in the conventional multipoint TS system of RFX-mod. By calculating the expected calibration errors for typical plasma scenarios we discuss the different possible choices of the calibration laser, the characteristics of the calibrating plasma and other system parameters with an impact on the application of the technique. For ITER core LIDAR TS, designed with Nd?:?YAG at 1064 nm as main laser, a ruby laser shows slightly better performances as a calibration laser compared with a second harmonic Nd?:?YAG and a calibration accuracy ˜1% can be achieved in a relatively small number of pairs of laser pulses. In RFX-mod the combination of a Nd?:?YAG and a Nd?:?YLF laser systems is the only viable choice, and we find that, in spite of the small difference between the two wavelengths (? = 1064 nm and ? = 1053 nm, respectively), dual-laser calibration is still possible to the required accuracy with an affordable number of pairs of laser shots.

Giudicotti, L.; Pasqualotto, R.

2014-04-01

153

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

NASA Astrophysics Data System (ADS)

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

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

2006-05-01

154

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

155

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

156

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

SciTech Connect

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

2014-08-28

157

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

PubMed

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. PMID:25371555

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

2014-08-28

158

White Paper for Developing Electromagnetic Particle Injector system for ITER on NSTX-U University of Washington (19 July 2012)  

E-print Network

White Paper for Developing Electromagnetic Particle Injector system for ITER on NSTX-U University of Washington (19 July 2012) 1/2 White Paper@aa.washington.edu This white paper describes our plans for developing a new system for safely

159

YALINA analytical benchmark analyses using the deterministic ERANOS code system.  

SciTech Connect

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

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

2009-08-31

160

Advanced vehicle systems assessment. Volume 4: Supporting analyses  

NASA Technical Reports Server (NTRS)

Volume 4 (Supporting Analyses) is part of a five-volume report, Advanced Vehicle Systems Assessment. Thirty-nine individuals, knowledgeable in advanced technology, were interviewed to obtain their preferences. Rankings were calculated for the eight groups they represented, using multiplicative and additive utility models. The four topics for consideration were: (1) preferred range for various battery technologies; (2) preferred battery technology for each of a variety of travel ranges; (3) most promising battery technology, vehicle range combination; and (4) comparison of the most preferred electric vehicle with the methanol-fuled, spark-ignition engine vehicle and with the most preferred of the hybrid vehicles.

Hardy, K.

1985-01-01

161

A graphical representation of protein based on a novel iterated function system  

NASA Astrophysics Data System (ADS)

In this article, a novel family of iterated function system (IFS) was introduced to outline a 2D graphical representation of protein sequences, which incorporates with various physicochemical properties of amino acids. Then a mathematical description was suggested to quantificationally compare the similarities and dissimilarities of protein sequences from their 2D curves. Based on this method, similarities/dissimilarities were compared among sequences of the ND5 proteins of nine different species, as well as sequences of eight ND6 proteins. The phylogenetic tree of the nine ND5 proteins was constructed according to Fuzzy cluster analysis. By correlation analysis, the ClustalW results were compared with our similarity/dissimilarity results and other graphical representation results to demonstrate the effectiveness of our approach.

Ma, Tingting; Liu, Yuxin; Dai, Qi; Yao, Yuhua; He, Ping-an

2014-06-01

162

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

PubMed

The equatorial vis/IR wide angle viewing system is present in four ITER diagnostic equatorial ports. This instrument will cover a large field of view with high spatial and temporal resolutions, to provide real time temperature measurements of plasma facing components, spectral data in the visible range, information on runaway electrons, and pellet tracking. This diagnostic needs to be reliable, precise, and long lasting. Its design is driven by both the tokamak severe environment and the high performances required for machine protection. The preliminary design phase is ongoing. Paramount issues are being tackled, relative to wide spectral band optical design, material choice, and optomechanical difficulties due to the limited space available for this instrument in the ports, since many other diagnostics and services are also present. Recent progress of the diagnostic optical design and status of associated R&D are presented. PMID:19044654

Davi, M; Corre, Y; Guilhem, D; Jullien, F; Reichle, R; Salasca, S; Travère, J M; de la Cal, E; Manzanares, A; de Pablos, J L; Migozzi, J B

2008-10-01

163

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

PubMed

The neutral beam injectors for ITER are designed to deliver hydrogen or deuterium atoms accelerated at 1 MV for a total power of 34 MW. Design of the neutral beam and of the ion source test facilities is presently ongoing. Among the various activities, also the definition and assessment of necessary diagnostics are being carried out. Within this framework, requirements and constraints of the diagnostic system will be discussed in the present paper with the aim of providing data relevant for protection, operation, characterization, and improvement of the performances of the test facilities. The definition of the most suitable locations for the diagnostics and of their preliminary integration into the mechanical design will be proposed. Proposals for the extraction of signals from the high voltage components will also be presented. PMID:19044620

Serianni, Gianluigi; Pomaro, Nicola; Pasqualotto, Roberto; Spolaore, Monica; Valisa, Marco

2008-10-01

164

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

SciTech Connect

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

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

2012-02-15

165

Matt Jewell ITER Organization  

E-print Network

in plasma. · CS coils are used to produce inductive flux and to ramp up plasma current; they also play) nuclear heating Background slides courtesy A. Devred #12;2/19 ITER Magnet System (1/2) · The ITER magnet a role in plasma shaping and vertical stability. · PF coils are used to control radial position

McDonald, Kirk

166

Unsteady Analyses of Valve Systems in Rocket Engine Testing Environments  

NASA Technical Reports Server (NTRS)

This paper discusses simulation technology used to support the testing of rocket propulsion systems by performing high fidelity analyses of feed system components. A generalized multi-element framework has been used to perform simulations of control valve systems. This framework provides the flexibility to resolve the structural and functional complexities typically associated with valve-based high pressure feed systems that are difficult to deal with using traditional Computational Fluid Dynamics (CFD) methods. In order to validate this framework for control valve systems, results are presented for simulations of a cryogenic control valve at various plug settings and compared to both experimental data and simulation results obtained at NASA Stennis Space Center. A detailed unsteady analysis has also been performed for a pressure regulator type control valve used to support rocket engine and component testing at Stennis Space Center. The transient simulation captures the onset of a modal instability that has been observed in the operation of the valve. A discussion of the flow physics responsible for the instability and a prediction of the dominant modes associated with the fluctuations is presented.

Shipman, Jeremy; Hosangadi, Ashvin; Ahuja, Vineet

2004-01-01

167

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

168

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

SciTech Connect

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

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

2008-03-16

169

Adaptive optimal control of unknown constrained-input systems using policy iteration and neural networks.  

PubMed

This paper presents an online policy iteration (PI) algorithm to learn the continuous-time optimal control solution for unknown constrained-input systems. The proposed PI algorithm is implemented on an actor-critic structure where two neural networks (NNs) are tuned online and simultaneously to generate the optimal bounded control policy. The requirement of complete knowledge of the system dynamics is obviated by employing a novel NN identifier in conjunction with the actor and critic NNs. It is shown how the identifier weights estimation error affects the convergence of the critic NN. A novel learning rule is developed to guarantee that the identifier weights converge to small neighborhoods of their ideal values exponentially fast. To provide an easy-to-check persistence of excitation condition, the experience replay technique is used. That is, recorded past experiences are used simultaneously with current data for the adaptation of the identifier weights. Stability of the whole system consisting of the actor, critic, system state, and system identifier is guaranteed while all three networks undergo adaptation. Convergence to a near-optimal control law is also shown. The effectiveness of the proposed method is illustrated with a simulation example. PMID:24808590

Modares, Hamidreza; Lewis, Frank L; Naghibi-Sistani, Mohammad-Bagher

2013-10-01

170

Synthesis of Trigeneration Systems: Sensitivity Analyses and Resilience  

PubMed Central

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

171

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

E-print Network

. It has attracted tremendous attention due to its high spectral efficiency and low receiver complexity in orthogonal frequency-division multiplexing (OFDM) systems to reduce the peak-to-average power ratio (PAPR to verify the analysis. Index Terms--Clipping, iterative decoding, orthogonal frequency

Ping, Li

172

Test Results From the PF Conductor Insert Coil and Implications for the ITER PF System  

Microsoft Academic Search

In this paper we report the main test results obtained on the Poloidal Field Conductor Insert coil (PFI) for the International Thermonuclear Experimental Reactor (ITER), built jointly by the EU and RF ITER parties, recently installed and tested in the CS Model Coil facility, at JAEA-Naka. During the test we (a) verified the DC and AC operating margin of the

D. Bessette; Luca Bottura; A. Devred; N. Mitchell; K. Okuno; Y. Nunoya; C. Sborchia; Y. Takahashi; A. Verweij; A. Vostner; R. Zanino; E. Zapretilina

2009-01-01

173

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

174

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

175

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 (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. [Fusion and Materials for Nuclear System Division, Oak Ridge National Laboratory, Oak Ridge (United States); Rasmussen, David A.; Hechler, Michael P. [U.S. ITER Project Office, Oak Ridge National Laboratory, Oak Ridge (United States); Pearce, Robert J. H.; Dremel, Mattias [ITER Organization, 13115 St. Paul-lez-Durance (France); Boissin, J.-C. [Consultant, Grenoble (France)

2014-01-29

176

A policy iteration approach to online optimal control of continuous-time constrained-input systems.  

PubMed

This paper is an effort towards developing an online learning algorithm to find the optimal control solution for continuous-time (CT) systems subject to input constraints. The proposed method is based on the policy iteration (PI) technique which has recently evolved as a major technique for solving optimal control problems. Although a number of online PI algorithms have been developed for CT systems, none of them take into account the input constraints caused by actuator saturation. In practice, however, ignoring these constraints leads to performance degradation or even system instability. In this paper, to deal with the input constraints, a suitable nonquadratic functional is employed to encode the constraints into the optimization formulation. Then, the proposed PI algorithm is implemented on an actor-critic structure to solve the Hamilton-Jacobi-Bellman (HJB) equation associated with this nonquadratic cost functional in an online fashion. That is, two coupled neural network (NN) approximators, namely an actor and a critic are tuned online and simultaneously for approximating the associated HJB solution and computing the optimal control policy. The critic is used to evaluate the cost associated with the current policy, while the actor is used to find an improved policy based on information provided by the critic. Convergence to a close approximation of the HJB solution as well as stability of the proposed feedback control law are shown. Simulation results of the proposed method on a nonlinear CT system illustrate the effectiveness of the proposed approach. PMID:23706414

Modares, Hamidreza; Naghibi Sistani, Mohammad-Bagher; Lewis, Frank L

2013-09-01

177

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

178

Adaptive switching detection algorithm for iterative-MIMO systems to enable power savings  

NASA Astrophysics Data System (ADS)

This paper attempts to tackle one of the challenges faced in soft input soft output Multiple Input Multiple Output (MIMO) detection systems, which is to achieve optimal error rate performance with minimal power consumption. This is realized by proposing a new algorithm design that comprises multiple thresholds within the detector that, in real time, specify the receiver behavior according to the current channel in both slow and fast fading conditions, giving it adaptivity. This adaptivity enables energy savings within the system since the receiver chooses whether to accept or to reject the transmission, according to the success rate of detecting thresholds. The thresholds are calculated using the mutual information of the instantaneous channel conditions between the transmitting and receiving antennas of iterative-MIMO systems. In addition, the power saving technique, Dynamic Voltage and Frequency Scaling, helps to reduce the circuit power demands of the adaptive algorithm. This adaptivity has the potential to save up to 30% of the total energy when it is implemented on Xilinx®Virtex-5 simulation hardware. Results indicate the benefits of having this "intelligence" in the adaptive algorithm due to the promising performance-complexity tradeoff parameters in both software and hardware codesign simulation.

Tadza, N.; Laurenson, D.; Thompson, J. S.

2014-11-01

179

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

180

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

NASA Technical Reports Server (NTRS)

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

Pak, Chan-gi; Lung, Shu

2009-01-01

181

Study on mitigation of pulsed heat load for ITER cryogenic system  

NASA Astrophysics Data System (ADS)

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

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

2015-03-01

182

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

SciTech Connect

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., E-mail: lasnier@LLNL.gov; Allen, S. L.; Ellis, R. E.; Fenstermacher, M. E.; McLean, A. G.; Meyer, W. H.; Morris, K.; Seppala, L. G. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States); Crabtree, K. [College of Optics, University of Arizona, Tucson, Arizona 85721 (United States); Van Zeeland, M. A. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

2014-11-15

183

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

184

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

E-print Network

Iterative decoding and codes on graphs were first devised by Gallager in 1960, and then rediscovered by Berrou, Glavieux and Thitimajshima in 1993. This technique plays an important role in modern communications, especially in coding theory...

Wang, Chia-Wen

2008-10-10

185

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

186

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

187

Improvements in Hanford TRU Program Utilizing Systems Modeling and Analyses  

SciTech Connect

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

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

2008-07-01

188

Noise performance of statistical model based iterative reconstruction in clinical CT systems  

NASA Astrophysics Data System (ADS)

The statistical model based iterative reconstruction (MBIR) method has been introduced to clinical CT systems. Due to the nonlinearity of this method, the noise characteristics of MBIR are expected to differ from those of filtered backprojection (FBP). This paper reports an experimental characterization of the noise performance of MBIR equipped on several state-of-the-art clinical CT scanners at our institution. The thoracic section of an anthropomorphic phantom was scanned 50 times to generate image ensembles for noise analysis. Noise power spectra (NPS) and noise standard deviation maps were assessed locally at different anatomical locations. It was found that MBIR lead to significant reduction in noise magnitude and improvement in noise spatial uniformity when compared with FBP. Meanwhile, MBIR shifted the NPS of the reconstructed CT images towards lower frequencies along both the axial and the z frequency axes. This effect was confirmed by a relaxed slice thicknesstradeoff relationship shown in our experimental data. The unique noise characteristics of MBIR imply that extra effort must be made to optimize CT scanning parameters for MBIR to maximize its potential clinical benefits.

Li, Ke; Tang, Jie; Chen, Guang-Hong

2014-03-01

189

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

E-print Network

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

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

2015-01-01

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

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

192

Progress of the development of the IPP RF negative ion source for the ITER neutral beam system  

Microsoft Academic Search

IPP Garching has successfully developed a RF-driven negative ion source for the ITER neutral beam injection system. The RF source is now an interesting alternative to the reference design with filamented sources due to its in principle maintenance-free operation. Current densities of 330 A m?2 and 230 A m?2 have been achieved for hydrogen and deuterium, respectively, at a pressure

P. Franzen; H. D. Falter; U. Fantz; W. Kraus; M. Berger; S. Christ-Koch; M. Fröschle; R. Gutser; B. Heinemann; S. Hilbert; S. Leyer; C. Martens; P. McNeely; R. Riedl; E. Speth; D. Wünderlich

2007-01-01

193

Experimental and numerical analyses on LiSO 4 and Li 2TiO 3 pebble beds used in a ITER test blanket module  

NASA Astrophysics Data System (ADS)

One of the possible configurations of test blanket module (TBM) which will be tested during the ITER operation phase is made up of neutron multiplier and breeder as pebble beds. This paper describes an experimental device for the determination of the pebble bed conductivity in presence of interstitial air. The tests were performed with a simultaneous compression of the bed in order to obtain the effective bed conductivity versus the axial deformation for several values of the temperature. The effective conductivities of LiSiO 4 and Li 2TiO 3 pebble beds, both in air and in vacuum, were determined. The packing factors of the beds were measured by means an ad hoc built instrumentation, based on the gamma ray backscattering. The experimental results have been compared with those of a theoretical model developed by the authors, obtaining a good agreement in terms of bed conductivity and stiffness.

Aquaro, Donato; Zaccari, Nicola

2007-08-01

194

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

195

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

SciTech Connect

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 thermal behavior of ITER during overpower events caused by thermal instability of the plasma has been analyzed. In a truly ignited operation (Q [approximately] [infinity]), the plasma reaches the beta limit in [approximately]6.5 (3.5) s after insertion of a + 10% fluctuation in fuel density, when the ITER89-L power law (the offset-linear law) is applied. The surface temperature of the divertor tiles rises to [approximately]1900[degrees]C, which may result in damage from erosion and thermal stress. On the other hand, the outboard and inboard structures maintain their integrity during overpower events if the cooling systems function normally. The code system will be integrated step by step to provide overall safety analyses for nuclear fusion reactions. 37 refs., 13 figs., 1 tab.

Honda, T.; Uda, T.; Maki, K.; Okazaki, T. (Hitachi Energy Research Laboratory (Japan)); Seki, Y.; Aoki, I. (Japan Atomic Energy Research Institute, Naka-gun (Japan))

1994-07-01

196

ITER shielding analysis  

SciTech Connect

Nuclear design studies were carried out to obtain essential data to aid in the design of the International Thermonuclear Experimental Reactor (ITER). The ITER blanket and shield system is being designed to handle 1.5{plus_minus}0.3 GW of fusion power and 3 MWa/m{sup 2} average neutron fluence. Analyses concentrated on two designs. The first blanket-shield design uses type 316 Stainless-Steel (316SS) as the structural material with water coolant. The second tritium breeding-blanket design uses liquid lithium as the breeding material and vandium alloy (V-5Cr-5Ti) for the structure. The stainless-steel blanket-shield consists of a beryllium coated copper first wall followed by alternating layers of stainless-steel and water. The breeding blanket uses V-5Cr-5Ti as the structural material, beryllium as a neutron multiplier, and liquid lithium as the tritium breeding material. Also, the first wall in this design is coated with beryllium. A layer of 120mm-thick tungsten-carbide is incorporated in the rear section of the breeding blanket to enhance its shielding characteristics. The second components of the shield for both designs are included in the vacuum vessel. Also, a layer of boron carbide and lead, nominally 50mm-thick, is attached to the outer surface of the vacuum vessel to reduce the heat load and activation in the toroidal field coils. The analysis of the divertor pumping duct suggests that the structure surrounding the duct will reduce the nuclear heating and radiation damage in the conductor regions of the TF coils adjacent to the duct opening to acceptable levels.

Santoro, R.T.; Gohar, Y.; Parker, R.R. [ITER Joint Central Team, Garching (Germany)] [and others

1994-12-31

197

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

198

Design of a low voltage, high current extraction system for the ITER Ion Source  

Microsoft Academic Search

A Test Facility is planned to be built in Padova to assemble and test the Neutral Beam Injector for ITER. In the same Test Facility the Ion Source will be tested in a dedicated facility planned to operate in parallel to the main 1 MV facility. Purpose of the full size Ion Source is to optimize the Ion Source performance

P. Agostinetti; V. Antoni; M. Cavenago; H. P. L. de Esch; G. Fubiani; D. Marcuzzi; S. Petrenko; N. Pilan; W. Rigato; G. Serianni; M. Singh; P. Sonato; P. Veltri; P. Zaccaria

2009-01-01

199

ITER Upper Port Plug handling cask system assessment and design proposals  

Microsoft Academic Search

The current design of the ITER cask for Upper Port Plugs has been evaluated. Careful reduction of the number of mechanical degrees of freedom is an opportunity to relax the tolerances in the design, resulting in cost reduction and reliability increase. A new kinematical design for the tractor module has a higher stiffness to weight ratio, reduces actuator forces by

J.-W. Pustjens; J.-P. Friconneau; C. J. M. Heemskerk; J. F. Koning; J.-P. Martins; P. C. J. N. Rosielle; M. Steinbuch

2011-01-01

200

The pre-compression system of the toroidal field coils in ITER  

Microsoft Academic Search

The toroidal field (TF) coils of ITER will undergo out-of-plane forces caused by the poloidal fields required to confine the plasma. These forces will be supported against overturning moments by links between the coils. In turn, these links consist of the inner intercoil structure (IIC), which is composed of two pairs (placed at the top and bottom part of the

J. Knaster; M. Ferrari; C. Jong; T. Vollmann

2007-01-01

201

Iterative detection of differentially modulated APSK signals in an OFDM transmission system  

Microsoft Academic Search

An iterative detection technique for DPSK and its extension to higher level DAPSK modulation schemes is presented. We consider the well-known OFDM transmission technique that requires, in combination with noncoherent detection, no channel state information. By simulation, it is shown that the proposed algorithm leads to a significant performance gain in terms of bit error rate.

Peter Haase; Hermann Rohling

2002-01-01

202

Performance comparison of iteratively filtered and decoded MDD and PSAM systems with linear complexity  

Microsoft Academic Search

Joint channel estimation and decoding in a time-varying Rayleigh fading channel is considered. Knowing that the optimal design has an exponential complexity which hinders the practicability, a reduced complexity approach is proposed. This approach keeps the existing channel estimation and decoding schemes almost intact, while applying the turbo or iterative processing principle to enable information exchange between them. Thus the

Hsuan-Jung Su; Evaggelos Geraniotis

1999-01-01

203

Rescheduling with iterative repair  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

204

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

205

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

206

The silicon trypanosome: a test case of iterative model extension in systems biology.  

PubMed

The African trypanosome, Trypanosoma brucei, is a unicellular parasite causing African Trypanosomiasis (sleeping sickness in humans and nagana in animals). Due to some of its unique properties, it has emerged as a popular model organism in systems biology. A predictive quantitative model of glycolysis in the bloodstream form of the parasite has been constructed and updated several times. The Silicon Trypanosome is a project that brings together modellers and experimentalists to improve and extend this core model with new pathways and additional levels of regulation. These new extensions and analyses use computational methods that explicitly take different levels of uncertainty into account. During this project, numerous tools and techniques have been developed for this purpose, which can now be used for a wide range of different studies in systems biology. PMID:24797926

Achcar, Fiona; Fadda, Abeer; Haanstra, Jurgen R; Kerkhoven, Eduard J; Kim, Dong-Hyun; Leroux, Alejandro E; Papamarkou, Theodore; Rojas, Federico; Bakker, Barbara M; Barrett, Michael P; Clayton, Christine; Girolami, Mark; Krauth-Siegel, R Luise; Matthews, Keith R; Breitling, Rainer

2014-01-01

207

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

Microsoft Academic Search

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

Samarjit Chakraborty; Simon Kunzli; Lothar Thiele

2003-01-01

208

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

209

Rescheduling with iterative repair  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

210

Gamma ray spectrometer for ITER  

SciTech Connect

Gamma diagnostics is considered to be primary for the confined ?-particles and runaway electrons measurements on ITER. The gamma spectrometer will be embedded into a neutron dump of the ITER Neutral Particle Analyzer diagnostic complex. It will supplement NPA measurements on the fuel isotope ratio and confined alphas/fast ions. In this paper an update on ITER gamma spectrometer developments is given. A new geometry of the system is described and detailed analysis of expected signals for the spectrometer is presented.

Gin, D.; Chugunov, I.; Shevelev, A.; Khilkevitch, E.; Doinikov, D.; Naidenov, V.; Pasternak, A.; Polunovsky, I. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Polytechnicheskaya 26, St. Petersburg, 194021 (Russian Federation); Kiptily, V. [EURATOM / CCFE Fusion Association, Abingdon, OX14 3DB (United Kingdom)

2014-08-21

211

Gamma ray spectrometer for ITER  

NASA Astrophysics Data System (ADS)

Gamma diagnostics is considered to be primary for the confined ?-particles and runaway electrons measurements on ITER. The gamma spectrometer will be embedded into a neutron dump of the ITER Neutral Particle Analyzer diagnostic complex. It will supplement NPA measurements on the fuel isotope ratio and confined alphas/fast ions. In this paper an update on ITER gamma spectrometer developments is given. A new geometry of the system is described and detailed analysis of expected signals for the spectrometer is presented.

Gin, D.; Chugunov, I.; Shevelev, A.; Khilkevitch, E.; Doinikov, D.; Naidenov, V.; Pasternak, A.; Polunovsky, I.; Kiptily, V.

2014-08-01

212

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

SciTech Connect

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. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Gehre, D. [Technical University of Dresden, IKTP, Zellescher Weg 19, 01062 Dresden (Germany); Kleizer, G. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and Budapest University of Technology and Economics, M?egyetem rkp. 3-9. H-1111 Budapest (Hungary); Raj, P. [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and Université Paris-Sud, 15 rue Georges Clemenceau, F-91405 Paris (France); Rovni, I. [Budapest University of Technology and Economics, M?egyetem rkp. 3-9. H-1111 Budapest (Hungary); Ruecker, Tom [Karlsruhe Institute of Technology (KIT), INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany and University of Applied Sciences Zittau-Goerlitz, Theodor-Körner-Allee 16, D-02754 Zittau (Germany)

2014-08-21

213

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

214

Non-destructive examination with infrared thermography system for ITER divertor components  

Microsoft Academic Search

In the first set of ITER divertor, the bottom segment of the inner and outer vertical target consists of the carbon-fiber-reinforced composite monoblock, the interlayer of the oxygen-free high-conductivity Cu and the cooling tube. In this part of the divertor, the capability to remove the high heat flux up to 20MW\\/m2 has to be provided. Therefore, the method of performance

Yohji Seki; Koichiro Ezato; Satoshi Suzuki; Kenji Yokoyama; Mikio Enoeda; Seiji Mori

2010-01-01

215

Value and cost analyses for solar thermal storage systems  

Microsoft Academic Search

Value and cost data for thermal energy storage are presented for solar thermal central receiver systems for which thermal energy storage appears to be attractive. Both solar thermal electric power and industrial process heat applications are evaluated. The value of storage is based on the cost for fossil fuel and solar thermal collector systems in 1990. The costing uses a

W. Luft; R. J. Copeland

1983-01-01

216

Value and cost analyses for solar thermal-storage systems  

Microsoft Academic Search

Value and cost data for thermal energy storage are presented for solar thermal central receiver systems for which thermal energy storage appears to be attractive. Both solar thermal electric power and industrial process heat applications are evaluated. The value of storage is based on the cost for fossil fuel and solar thermal collector systems in 1990. The costing uses a

W. Luft; R. J. Copeland

1983-01-01

217

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

218

Solar Electric Power System Analyses for Mars Surface Missions  

NASA Technical Reports Server (NTRS)

The electric power system is a crucial element of any architecture supporting human surface exploration of Mars. In this paper, we describe the conceptual design and detailed analysis of solar electric power system using photovoltaics and regenerative fuel cells to provide surface power on Mars. System performance, mass and deployed area predictions are discussed along with the myriad environmental factors and trade study results that helped to guide system design choices. Based on this work, we have developed a credible solar electric power option that satisfies the surface power requirements of a human Mars mission. The power system option described in this paper has a mass of approximately 10 metric tons, a approximately 5000-sq m deployable photovoltaic array using thin film solar cell technology.

Kerslake, Thomas W.; Kohout, Lisa L.

1999-01-01

219

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

SciTech Connect

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

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

2014-04-15

220

Analyses of power system vulnerability and total transfer capability  

E-print Network

. In reliability analysis, especially with Monte Carlo simulation, computation time is a function not only of a large number of simulations, but also time-consuming system state evaluation, such as OPF (Optimal Power Flow) and stability assessment. Theoretical...

Yu, Xingbin

2006-04-12

221

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

222

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

223

Modelling the swarm: Analysing biological and engineered swarm systems  

Microsoft Academic Search

In this article, we discuss the current research efforts on swarm systems and on the motivation of mathematical modelling of such distributed and self-organizing systems. Obviously, a special emphasis is given to those articles which were carefully selected for the special issue at hand. These articles demonstrate how mathematical models of different kinds – bottom-up agent models and top-down model

Heiko Hamann; Thomas Schmickl

2011-01-01

224

Modelling the swarm: Analysing biological and engineered swarm systems  

Microsoft Academic Search

In this article, we discuss the current research efforts on swarm systems and on the motivation of mathematical modelling of such distributed and self-organizing systems. Obviously, a special emphasis is given to those articles which were carefully selected for the special issue at hand. These articles demonstrate how mathematical models of different kinds – bottom-up agent models and top-down model

Heiko Hamann; Thomas Schmickl

2012-01-01

225

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

226

Various Analyses of Structures and Systems Pertaining to Optical Communications  

NASA Technical Reports Server (NTRS)

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

Petersen, Collin W.

2005-01-01

227

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

228

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

229

Deviational analyses for validating regulations on real systems  

E-print Network

of dependability assurance is safety; national and interna- tional procedures require operators of aircraft is a traditional way of exploring the safety of systems. The results of deviational analysis contribute to tradi- tional safety cases and safety arguments. We extend deviational analysis to other aspects

Kelly, Tim

230

Cost Analyses of Fuel Cell Stacks/Systems  

E-print Network

. Romesh Kumar #12;2EC_DOE_D0006_H2&FC_MERIT_REVIEW_MAY2003 DOE Objectives For PEMFC powertrains% BarriersBarriers N. Cost (Fuel-Flexible Fuel Processor) O. Stack Material and Manufacturing Cost PEMFC an independent cost estimate of PEMFC system costs including a sensitivity analysis to: ­ Operating parameters

231

A System for Integrated Reliability and Safety Analyses  

NASA Technical Reports Server (NTRS)

We present an integrated reliability and aviation safety analysis tool. The reliability models for selected infrastructure components of the air traffic control system are described. The results of this model are used to evaluate the likelihood of seeing outcomes predicted by simulations with failures injected. We discuss the design of the simulation model, and the user interface to the integrated toolset.

Kostiuk, Peter; Shapiro, Gerald; Hanson, Dave; Kolitz, Stephan; Leong, Frank; Rosch, Gene; Coumeri, Marc; Scheidler, Peter, Jr.; Bonesteel, Charles

1999-01-01

232

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

NASA Astrophysics Data System (ADS)

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

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

233

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

234

District Heating Systems Performance Analyses. Heat Energy Tariff  

NASA Astrophysics Data System (ADS)

The paper addresses an important element of the European energy sector: the evaluation of district heating (DH) system operations from the standpoint of increasing energy efficiency and increasing the use of renewable energy resources. This has been done by developing a new methodology for the evaluation of the heat tariff. The paper presents an algorithm of this methodology, which includes not only a data base and calculation equation systems, but also an integrated multi-criteria analysis module using MADM/MCDM (Multi-Attribute Decision Making / Multi-Criteria Decision Making) based on TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). The results of the multi-criteria analysis are used to set the tariff benchmarks. The evaluation methodology has been tested for Latvian heat tariffs, and the obtained results show that only half of heating companies reach a benchmark value equal to 0.5 for the efficiency closeness to the ideal solution indicator. This means that the proposed evaluation methodology would not only allow companies to determine how they perform with regard to the proposed benchmark, but also to identify their need to restructure so that they may reach the level of a low-carbon business.

Ziemele, Jelena; Vigants, Girts; Vitolins, Valdis; Blumberga, Dagnija; Veidenbergs, Ivars

2014-12-01

235

Solar Power System Analyses for Electric Propulsion Missions  

NASA Technical Reports Server (NTRS)

Solar electric propulsion (SEP) mission architectures are applicable to a wide range of NASA missions including human Mars exploration and robotic exploration of the outer planets. In this paper, we discuss the conceptual design and detailed performance analysis of an SEP stage electric power system (EPS). EPS performance, mass and area predictions are compared for several PV array technologies. Based on these studies, an EPS design for a 1-MW class, Human Mars Mission SEP stage was developed with a reasonable mass, 9.4 metric tons, and feasible deployed array area, 5800 sq m. An EPS was also designed for the Europa Mapper spacecraft and had a mass of 151 kg and a deployed array area of 106 sq m.

Kerslake, Thomas W.; Gefert, Leon P.

1999-01-01

236

New progress of ITER-PF strand production in WST  

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

237

System analyses on advanced nuclear fuel cycle and waste management  

NASA Astrophysics Data System (ADS)

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 included in commercial spent-nuclear fuel (CSNF) is evaluated. With the latter, an optimized waste loading and composition in solidification of HLW are determined and the volume reduction of waste packages associated with CSNF is evaluated. WACOM, a reactor system analysis code developed in this study for burnup calculation, is validated by ORIGEN2.1 and MCNP. WACOM is used to perform multicycle analysis for the reference lead-bismuth eutectic (LBE) cooled transmuter. By applying the results of this analysis to the reference ATW deployment scenario considered in the ATW roadmap, the HLW generated from the ATW fuel cycle is quantified and the reduction of TRU inventory contained in CSNF is evaluated. A linear programming (LP) model has been developed for determination of an optimized waste loading and composition in solidification of HLW. The model has been applied to a US-defense HLW. The optimum waste loading evaluated by the LP model was compared with that estimated by the Defense Waste Processing Facility (DWPF) in the US and a good agreement was observed. The LP model was then applied to the volume reduction of waste packages associated with CSNF. Based on the obtained reduction factors, the expansion of Yucca Mountain Repository (YMR) capacity is evaluated. It is found that with the reference ATW system, the TRU contained in CSNF could be reduced by a factor of ˜170 in terms of inventory and by a factor of ˜40 in terms of toxicity under the assumed scenario. The number of waste packages related to CSNF could be reduced by a factor of ˜8 in terms of volume and by factor of ˜10 on the basis of electricity generation when a sufficient cooling time for discharged spent fuel and zero process chemicals in HLW are assumed. The expansion factor of Yucca Mountain Repository capacity is estimated to be a factor of 2.4, much smaller than the reduction factor of CSNF waste packages, due to the existence of DOE-owned spent fuel and HLW. The YMR, however, could support 10 times greater electricity generation as long as the statutory capacity of DOE-owned SNF and HLW remains unchanged. This study also showed that the reduction of the number of waste packages could strongly be subject to the heat generation rate of HLW and the amount of process chemicals contained in HLW. For a greater reduction of the number of waste packages, a sufficient cooling time for discharged fuel and efforts to minimize the amount of process chemicals contained in HLW are crucial.

Cheon, Myeongguk

238

Sensitive Optical and Microfluidic Systems for Cellular Analyses  

NASA Astrophysics Data System (ADS)

Investigating rare cells and heterogeneous subpopulations is challenging for a myriad reasons. This dissertation describes novel techniques to analyze single molecules, synaptic vesicles, and rare circulating tumor cells. The eDAR platform for isolating rare cells in fluids provides a new method to monitor breast cancer status in patients as well as to guide research for personalized treatment and efficacy. In a side-by-side comparison with CellSearch, eDAR detected CTCs in all 20 Stage IV metastatic breast cancer patients while the CellSearch system found CTCs in just 8 patients. The single-molecule capillary electrophoresis technology is a method to characterize an entire sample one molecule at a time, providing detailed information about the absolute number and nature of molecules present in a sample. The nFASS platform has the potential to apply the advantages that currently exist in flow cytometry to the study of items on a much smaller scale such as subcellular organelles and nanometer-sized objects. For example, the isolation of subpopulations of synaptic vesicles will allow for detailed protein quantification and identification in the study of neurological diseases. These tools facilitate fundamental investigation of objects ranging from single molecules to single cells.

Schiro, Perry G.

239

Design and RF measurements of a 5 GHz 500 kW window for the ITER LHCD system  

E-print Network

CEA/IRFM is conducting R\\&D efforts in order to validate the critical RF components of the 5 GHz ITER LHCD system, which is expected to transmit 20 MW of RF power to the plasma. Two 5 GHz 500 kW BeO pill-box type window prototypes have been manufactured in 2012 by the PMB Company, in close collaboration with CEA/IRFM. Both windows have been validated at low power, showing good agreement between measured and modeling, with a return loss better than 32 dB and an insertion loss below 0.05 dB. This paper reports on the window RF design and the low power measurements. The high power tests up to 500kW have been carried out in March 2013 in collaboration with NFRI. Results of these tests are also reported. In the current ITER LHCD design, 20 MW Continuous Wave (CW) of Radio-Frequency power at 5 GHz are expected to be generated and transmitted to the plasma. In order to separate the vacuum vessel pressure from the cryostat waveguide pressure, forty eight 5 GHz 500kW CW windows are to be assembled on the waveguide...

Hillairet, Julien; Dechambre, N; Delpech, L; Ekedahl, A; Faure, N; Goniche, M; Kim, J; Larroque, S; Magne, R; Marfisi, L; Namkung, W; Park, H; Park, S; Poli, S; Vulliez, K

2015-01-01

240

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

NASA Astrophysics Data System (ADS)

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

Xu, Jingyan; Tsui, Benjamin M. W.

2012-06-01

241

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

ERIC Educational Resources Information Center

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

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

2004-01-01

242

Yucca Mountain Project total-system performance assessment preliminary analyses: Overview; Draft  

Microsoft Academic Search

Sandia National Laboratories and Pacific Northwest Laboratory have produced a coordinated initial total-system performance assessment analysis for the potential repository at Yucca Mountain. Analyses included radionuclide transport via groundwater and gas flow, human intrusion, tectonism, and basaltic igneous intrusion. Both abstracted and detailed calculations were used for the analyses. Probabilistic release distributions were calculated for the individual components, and a

R. W. Barnard; H. A. Dockery

1991-01-01

243

A non-linear iterative method for multi-layer DOT sub-surface imaging system.  

PubMed

Diffuse Optical Tomography (DOT) has become an emerging non-invasive technology, and has been widely used in clinical diagnosis. Functional near-infrared (FNIR) is one of the important applications of DOT. However, FNIR is used to reconstruct two-dimensional (2D) images for the sake of good spatial and temporal resolution. In this paper we propose a multiple-input and multiple-output (MIMO) based data extraction algorithm method in order to increase the spatial and temporal resolution. The non-linear iterative method is used to reconstruct better resolution images layer by layer. In terms of theory, the simulation results and original images are nearly identical. The proposed reconstruction method performs good spatial resolution, and has a depth resolutions capacity of three layers. PMID:25569931

Hou, Hsiang-Wen; Wu, Shih-Yang; Sun, Hao-Jan; Fang, Wai-Chi

2014-01-01

244

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

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

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

PubMed

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

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

2012-01-01

247

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

PubMed Central

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

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

2012-01-01

248

The two-level FETI method for static and dynamic plate problems Part I: An optimal iterative solver for biharmonic systems  

Microsoft Academic Search

We present a Lagrange multiplier based substructuring method for solving iteratively large-scale systems of equations arising from the finite element discretization of static and dynamic plate bending problems. The proposed method is essentially an extension of the FETI domain decomposition algorithm to fourth-order problems. The main idea is to enforce exactly the continuity of the transverse displacement field at the

Charbel Farhat; Jan Mandel

1998-01-01

249

Performance metrics for liquid chromatography-tandem mass spectrometry systems in proteomics analyses.  

PubMed

A major unmet need in LC-MS/MS-based proteomics analyses is a set of tools for quantitative assessment of system performance and evaluation of technical variability. Here we describe 46 system performance metrics for monitoring chromatographic performance, electrospray source stability, MS1 and MS2 signals, dynamic sampling of ions for MS/MS, and peptide identification. Applied to data sets from replicate LC-MS/MS analyses, these metrics displayed consistent, reasonable responses to controlled perturbations. The metrics typically displayed variations less than 10% and thus can reveal even subtle differences in performance of system components. Analyses of data from interlaboratory studies conducted under a common standard operating procedure identified outlier data and provided clues to specific causes. Moreover, interlaboratory variation reflected by the metrics indicates which system components vary the most between laboratories. Application of these metrics enables rational, quantitative quality assessment for proteomics and other LC-MS/MS analytical applications. PMID:19837981

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

2010-02-01

250

On some structure–morphology problems by the extended partitioned iterated function system (PIFS-SF)  

Microsoft Academic Search

Using a newly developed technique of coding 2D sets (PIFS-SF) we have shown how to analyse the family of sets (images) given with different resolutions. Based on the number of codes (PIFS-SF) we have been able to describe quantitatively the high-resolution structure (HRS) and low-resolution structure (LRS), as well as supramolecular structure (SMS). Following the essence of aggregation processes (crystallization,

Zbigniew J. Grzywna; Jacek Stolarczyk

2002-01-01

251

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

252

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

253

The thermal shields for the ITER magnet system: thermal, structural and assembly aspects  

Microsoft Academic Search

The thermal shield system is a continuous barrier between the magnet system operating at 4.5 K and the warm tokamak components. It provides a substantial reduction of both total and local thermal loads to the cold structures to achieve the limits required for normal operation of the superconducting magnet system and maximum heat load of the cryogenic plant. This paper

V Bykov; A Nishikawa; G Dalle Carbonare; A Alekseev; S Grigoriev; Yu Krasikov; V Krylov; A Labusov; M Nakahira

2001-01-01

254

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

255

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

NASA Astrophysics Data System (ADS)

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

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

256

Integrating cognitive analyses in a large-scale system design process  

Microsoft Academic Search

This paper describes the integration of cognitive analysis into the early stages of design of a new, large-scale system—a next generation US Navy Surface combatant. Influencing complex system designs in ways cognizant of human–system integration principles requires work products that are timely and tightly coupled to other elements of the design process. Because analyses were conducted simultaneously with the design

Ann M. Bisantz; Emilie M. Roth; Bart Brickman; Laura Lin Gosbee; Larry Hettinger; James Mckinney

2003-01-01

257

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

258

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

NASA Astrophysics Data System (ADS)

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

Elias, Joseph A.

1995-06-01

259

Disturbance rejection performance analyses of closed loop control systems by reference to disturbance ratio.  

PubMed

This study investigates disturbance rejection capacity of closed loop control systems by means of reference to disturbance ratio (RDR). The RDR analysis calculates the ratio of reference signal energy to disturbance signal energy at the system output and provides a quantitative evaluation of disturbance rejection performance of control systems on the bases of communication channel limitations. Essentially, RDR provides a straightforward analytical method for the comparison and improvement of implicit disturbance rejection capacity of closed loop control systems. Theoretical analyses demonstrate us that RDR of the negative feedback closed loop control systems are determined by energy spectral density of controller transfer function. In this manner, authors derived design criteria for specifications of disturbance rejection performances of PID and fractional order PID (FOPID) controller structures. RDR spectra are calculated for investigation of frequency dependence of disturbance rejection capacity and spectral RDR analyses are carried out for PID and FOPID controllers. For the validation of theoretical results, simulation examples are presented. PMID:25311160

Alagoz, Baris Baykant; Deniz, Furkan Nur; Keles, Cemal; Tan, Nusret

2015-03-01

260

On the performance of iterative receivers for interfering MIMO-OFDM systems in measured  

E-print Network

inter-symbol interference and enhance system capacity through increased diversity, spatial multiplexing/base stations. Each stream is encoded via convolutional coding and random interleaving, with code- words Frequency Division Multiplexing (MIMO-OFDM) system, operating in a real indoor environment. The base

Müller, Ralf R.

261

Spectroscopic Measurement System for ITER Divertor Plasma: Impurity Influx Monitor (divertor)  

SciTech Connect

The detailed design of the Impurity Influx Monitor (divertor) has been carried out to provide the measurement capability in the harsh environment such as higher irradiation levels of neutron, gamma-ray and particles than in present devices. The in-situ calibration system using a micro retro-reflector array has been developed to monitor the sensitivity change of the optical system due to the environmental effects. The optical alignment system for the Monitor has been developed by using a dedicated optics for alignment in the collection optics for measurement.

Sugie, Tatsuo; Ogawa, Hiroaki; Kusama, Yoshinori [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka-shi, Ibaraki, 311-0193 (Japan); Kasai, Satoshi [Nippon Advanced Technology, 3129-45 Muramatsu, Tokai-mura, Naka-gun, Ibaraki 319-1112 (Japan)

2008-03-12

262

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

263

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

Microsoft Academic Search

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

C. Y. Wang; Y. Tang; A. H. Marchertas

1991-01-01

264

Morphologic and Morphometric Analyses of Fluvial Systems in the Southern Highlands of Mars  

NASA Technical Reports Server (NTRS)

Morphologic and Morphometric Analyses of Fluvial Systems in the Southern Highlands of Mars [#1844] Geologic and geomorphic mapping, image analysis, and hydrologic modeling are being used to characterize the morphology and morphometry of circum-Hellas and circum-Isidis valley networks in order to determine the process(es) of network formation.

Mest, S. C.; Crown, D. A.

2004-01-01

265

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

266

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

267

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

SciTech Connect

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

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

2014-09-01

268

Space-Frequency Bit-Interleaved Convolutional and Turbo Coded OFDM Systems with Simplified Iterative Approaches  

Microsoft Academic Search

In this paper, space-time bit-interleaved coded OFDM (orthogonal frequency division multiplexing) modulated systems are studied. Using multiple antennas at transmitter and receiver side, spatial diversity can be exploited with ordinary channel codes followed by an interleaver. Moreover, the combined use with OFDM modulation enable effective frequency selectivity exploitation in multipath channels. High spectral efficiency can be achieved using high modulation

Antonio Assalini; Silvano Pupolin; Fabio Osnato

269

Iterative Interference Cancellation for Co-Channel Multicarrier and Narrowband Systems  

E-print Network

systems due to the co-channel interference (CCI) problem. In this paper, an efficient CCI cancellation performance degradation due to the co- channel interference (CCI). Earlier examples of coexistence studies, which leads to an inefficient spectrum utilization, or a shared- spectrum approach [4], [5], where CCI

Arslan, Hüseyin

270

Design of Electron Cyclotron Heating and Current Drive System of ITER  

Microsoft Academic Search

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

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

2007-01-01

271

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

272

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

273

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

SciTech Connect

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

Wurden, G.A.

1995-09-01

274

Portable, fully autonomous, ion chromatography system for on-site analyses.  

PubMed

The basic operating principles of a portable, fully autonomous, ion chromatography system are described. The system affords the user the ability to collect and analyze samples continuously for 27 days, or about 1930 injections before needing any user intervention. Within the 13 kg system, is a fully computer controlled autosampling, chromatography and data acquisition system. An eluent reflux device (ERD), which integrates eluent suppression and generation in a single multi-chambered device, is used to minimize eluent consumption. During operation, about 1 ?L of water per minute is lost to waste while operating standard-bore chromatography at 0.5 mL min(-1) due to eluent refluxing. Over the course of 27 days, about 100mL of rinse water is consumed, effectively eliminating waste production. Data showing the reproducibility (below 1% relative standard deviation over 14 days) of the device is also presented. Chromatographic analyses of common anions (Cl(-), NO3(-), SO4(2-), PO4(3-)), is accomplished in under 15 min using a low backpressure guard column with ? 25 mM KOH isocratic elution. For detection, a small capacitively-coupled contactless conductivity detector (C4D) is employed, able to report analytes in the sub to low micromolar range. Preconcentration of the injected samples gives a 50-fold decrease in detection limits, primarily utilized for in-situ detection of phosphate (LOQ 10 ?g L(-1)). Field analyses are shown for multiple on-site analyses of stream water indifferent weather conditions. PMID:24913366

Elkin, Kyle R

2014-07-25

275

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

276

Metabolic capabilities and systems fluctuations in Haloarcula marismortui revealed by integrative genomics and proteomics analyses  

PubMed Central

The 1,310 Haloarcula marismortui proteins identified from mid-log and late-log phase soluble and membrane proteomes were analyzed in metabolic and cellular process networks to predict the available systems and systems fluctuations upon environmental stresses. When the connected metabolic reactions with identified proteins were examined, the availability of a number of metabolic pathways and a highly connected amino acid metabolic network were revealed. Quantitative spectral count analyses suggested 300 or more proteins might have expression changes in late-log phase. Among these, integrative network analyses indicated approximately 106 were metabolic proteins which might have growth-phase dependent changes. Interestingly, a large proportion of proteins in affected biomodules had same trend of changes in spectral counts. Disregard the magnitude of changes, we had successfully predicted and validated the expression changes of nine genes including the rimK, gltCP, rrnAC, and argC in lysine biosynthesis pathway which were downregulated in late-log phase. This study had not only revealed the expressed proteins but also the availability of biological systems in two growth phases, systems level changes in response to the stresses in late-log phase, cellular locations of identified proteins, and the likely regulated genes to facilitate further analyses in the postgenomic era. PMID:21598921

Chu, Lichieh Julie; Yang, Hanyin; Shih, Peiyin; Kao, Yuchieh; Tsai, Yihsuan Shannon; Chen, Jinzhi; Huang, Gueitang; Weng, Rueyhung Roc; Ting, Ying Sonia; Fang, Xuefeng; von Haller, Priska D.; Goodlett, David R.; Ng, Wailap Victor

2011-01-01

277

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

NASA Astrophysics Data System (ADS)

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

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

2009-07-01

278

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

279

Evaluation of Clipping Based Iterative PAPR Reduction Techniques for FBMC Systems  

PubMed Central

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

2014-01-01

280

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

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

Cyclic structural analyses of anisotropic turbine blades for reusable space propulsion systems. [ssme fuel turbopump  

NASA Technical Reports Server (NTRS)

Turbine blades for reusable space propulsion systems are subject to severe thermomechanical loading cycles that result in large inelastic strains and very short lives. These components require the use of anisotropic high-temperature alloys to meet the safety and durability requirements of such systems. To assess the effects on blade life of material anisotropy, cyclic structural analyses are being performed for the first stage high-pressure fuel turbopump blade of the space shuttle main engine. The blade alloy is directionally solidified MAR-M 246 alloy. The analyses are based on a typical test stand engine cycle. Stress-strain histories at the airfoil critical location are computed using the MARC nonlinear finite-element computer code. The MARC solutions are compared to cyclic response predictions from a simplified structural analysis procedure developed at the NASA Lewis Research Center.

Manderscheid, J. M.; Kaufman, A.

1985-01-01

283

Cyclic structural analyses of anisotropic turbine blades for reusable space propulsion systems  

NASA Technical Reports Server (NTRS)

Turbine blades for reusable space propulsion systems are subjects to severe thermomechanical loading cycles that result in large inelastic strains and very short lives. These components require the use of anisotropic high temperature alloys to meet the safety and durability requirements of such systems. To assess the effects on blade life of material anisotropy, cyclic structural analyses are being performed for the first stage high pressure fuel turbopump blade (HPFTB) of the space shuttle main engine (SSME). The blade alloy is directionally solidified MAR-M 246 alloy. The analyses are based on a typical test stand engine cycle. Stress-strain histories at the airfoil critical location are computed using the MARC nonlinear finite element computer code.

Manderscheid, J. M.; Kaufman, A.

1985-01-01

284

Preparee au Laboratoire d'Analyse et d'Architecture des Syst`emes du CNRS  

E-print Network

de Lorraine et Alain Th´eron, Professeur agr´eg´e au Lyc´ee Pierre de Fermat `a Toulouse. Je lesTH`ESE Pr´epar´ee au Laboratoire d'Analyse et d'Architecture des Syst`emes du CNRS En vue de l'obtention du Doctorat de l'Universit´e Paul Sabatier de Toulouse Sp´ecialit´e Automatique Par Christophe FARGES

Paris-Sud XI, Université de

285

Energy and exergy analyses of an ice-on-coil thermal energy storage system  

Microsoft Academic Search

In this study, energy and exergy analyses are carried out for the charging period of an ice-on-coil thermal energy storage system. The present model is developed using a thermal resistance network technique. First, the time-dependent variations of the predicted total stored energy, mass of ice, and outlet temperature of the heat transfer fluid from a storage tank are compared with

Mehmet Akif Ezan; Aytunç Erek; Ibrahim Dincer

2011-01-01

286

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

287

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

288

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

SciTech Connect

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

Sutton, Stephen R. [University of Chicago

2006-04-05

289

System design analyses of a rotating advanced-technology space station for the year 2025  

NASA Technical Reports Server (NTRS)

Studies of an advanced technology space station configured to implement subsystem technologies projected for availability in the time period 2000 to 2025 is documented. These studies have examined the practical synergies in operational performance available through subsystem technology selection and identified the needs for technology development. Further analyses are performed on power system alternates, momentum management and stabilization, electrothermal propulsion, composite materials and structures, launch vehicle alternates, and lunar and planetary missions. Concluding remarks are made regarding the advanced technology space station concept, its intersubsystem synergies, and its system operational subsystem advanced technology development needs.

Queijo, M. J.; Butterfield, A. J.; Cuddihy, W. F.; Stone, R. W.; Wrobel, J. R.; Garn, P. A.; King, C. B.

1988-01-01

290

Experimental results of a 70 kA high temperature superconductor current lead demonstrator for the ITER magnet system  

Microsoft Academic Search

In the frame of the European Fusion Technology Programme, the Forschungszentrum Karlsruhe and the CRPP Villigen have designed and built a 70 kA current lead for the ITER TF Coils using High Temperature Superconductors (HTS). At the beginning of 2004 the HTS current lead was installed and tested in the TOSKA facility of the Forschungszentrum Karlsruhe. The scope of the

R. Heller; S. M. Darweschsad; G. Dittrich; W. H. Fietz; S. Fink; W. Herz; F. Hurd; A. Kienzler; A. Lingor; I. Meyer; G. Nother; M. Susser; V. L. Tanna; A. Vostner; R. Wesche; F. Wuchner; G. Zahn

2005-01-01

291

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

E-print Network

Iterative Optimal and Adaptive Control of a Near Isothermal Liquid Piston Air Compressor. Simon Abstract-- The power density and efficiency of high compres- sion ratio (200:1) air compressors/expanders on the heat transfer capability within compres- sor/expander. In previous papers, we have shown

Li, Perry Y.

292

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

NASA Technical Reports Server (NTRS)

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

1979-01-01

293

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

NASA Technical Reports Server (NTRS)

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

1979-01-01

294

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

295

RBMK coupled neutronics/thermal-hydraulics analyses by two independent code systems  

SciTech Connect

This paper presents the coupled neutronics/thermal-hydraulics activities carried out in the framework of the part B of the TACIS project R2.03/97, 'Software development for accident analysis of RBMK reactors in Russia'. Two independent code systems were assembled, one from the Russian side and the other from the Western side, for studying RBMK core transients. The Russian code system relies on the use of code UNK for neutron data libraries generation and the three-dimensional neutron kinetics thermal-hydraulics coupled codes BARS-KORSAR for plant transient analyses. The Western code system is instead based on the lattice physics code HELIOS and on the RELAP5-3D C code. Several activities were performed for testing code system's capabilities: the neutron data libraries were calculated and verified by precise Monte Carlo calculations, the coupled codes' steady state results were compared with plant detectors' data, and calculations of several transients were compared. Finally, both code systems proved to have all the capabilities for addressing reliable safety analyses of RBMK reactors. (authors)

Parisi, C.; D'Auria, F. [Univ. of Pisa, Dept. of Mechanical, Nuclear and Production Engineering, via Diotisalvi, 2, 56100 Pisa (Italy); Malofeev, V. [Kurchatov Inst., Kurchatov Square 1, Moscow 123182 (Russian Federation); Ivanov, B.; Ivanov, K. [Pennsylvania State Univ., RDFMG, 230 Reber Building, Univ. Park, PA 16802 (United States)

2006-07-01

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

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

SciTech Connect

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

NONE

1997-03-01

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

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

300

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

ERIC Educational Resources Information Center

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

Steiner-Khamsi, Gita

2012-01-01

301

US ITER Project Brad Nelson  

E-print Network

US ITER Project Progress Brad Nelson Chief Engineer, US ITER Project Office Fusion Energy Sciences Advisory Committee September 23, 2014 #12;ITER Tokamak Core in Building 9/23/14 FESAC ITER Progress/Nelson 2 #12;9/23/14 FESAC ITER Progress/Nelson 3 Site Progress #12;Recent Activities 9/23/14 FESAC ITER

302

The topology of chaotic iterations  

E-print Network

Chaotic iterations have been introduced on the one hand by Chazan, Mi- ranker [6] and Miellou [10] in a numerical analysis context, and on the other hand by Robert [12] and Pellegrin [11] in the discrete dynamical systems frame- work. In both cases, the objective was to derive conditions of convergence of such iterations to a fixed state. In this paper, a new point of view is presented, the goal here is to derive conditions under which chaotic iterations admit a chaotic behaviour in a rigorous mathematical sense. Contrary to what has been studied in the literature, convergence is not desired. More precisely, we establish in this paper a link between the concept of chaotic iterations on a finite set and the notion of topological chaos [9], [7], [8]. We are motivated by concrete applications of our approach, such as the use of chaotic boolean iterations in the computer security field. Indeed, the concept of chaos is used in many areas of data security without real rigorous theoretical foundations, and without using the fundamental properties that allow chaos. The wish of this paper is to bring a bit more mathematical rigour in this field. This paper is an extension of[3], and a work in progress.

Jacques M. Bahi; Christophe Guyeux

2008-10-26

303

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

304

Iterative speed improvement for solving slowly varying total least squares problems  

NASA Astrophysics Data System (ADS)

Many problems in signal processing, modal analysis, system identification, etc., give rise to an overdetermined set of linear equations AX ? B. Whenever both the observation matrix B and the data matrix A are inaccurate, the total least squares (TLS) method is appropriate for estimating the unknown parameters X. Since the TLS solution is deduced from only one right singular vector or, in general, a basis of the right singular subspace associated with the smallest singular values of the data [ A; B], the computational speed can be improved by only calculating those desired base vectors. If a priori information is available (e.g. the TLS solution at a previous time step when slowly varying sets of equations must be solved at each time instant), iterative methods are appropriate to compute those base vectors. It is shown in this paper that inverse iteration is the most efficient iterative technique for solving generic TLS problems of known rank. Two algorithms for subspace inverse iteration are presented. Their convergence properties and applicability in solving TLS problems are analysed. Based on the convergence rate and the operation counts in each iteration step, these iterative algorithms are compared in efficiency with the direct computation methods—classical TLS and partial TLS. In particular, the efficiency of these methods is illustrated in a practical real life problem, namely multiple input estimation of frequency response functions.

Van Hufel, Sabine; Vandewalle, Joos

1988-10-01

305

Flight test and analyses of the B-1 structural mode control system at supersonic flight conditions  

NASA Technical Reports Server (NTRS)

A practical structural mode control system (SMCS) that could be turned on at takeoff and be left on for the entire flight was demonstrated. The SMCS appears to be more effective in damping the key fuselage bending modes at supersonic speeds than at the design point of Mach 0.85 (for fixed gains). The SMCS has an adverse effect on high frequency symmetric modes; however, this adverse effect did not make the system unstable and does not appear to affect ride quality performance. The vertical ride quality analyses indicate that the basic configuration without active systems is satisfactory for long term exposure. If clear air turbulence were to be encountered, indications are that the SMCS would be very effective in reducing the adverse accelerations. On the other hand, lateral ride quality analyses indicate that the aircraft with the SMCS on does not quite meet the long term exposure criteria, but would be satisfactory for shot term exposure at altitude. Again, the lateral SMCS was shown to be very effective in reducing peak lateral accelerations.

Wykes, J. H.; Kelpl, M. J.; Brosnan, M. J.

1983-01-01

306

Assessment of Tools and Data for System-Level Dynamic Analyses  

SciTech Connect

The only fuel cycle for which dynamic analyses and assessments are not needed is the null fuel cycle - no nuclear power. For every other concept, dynamic analyses are needed and can influence relative desirability of options. Dynamic analyses show how a fuel cycle might work during transitions from today's partial fuel cycle to something more complete, impact of technology deployments, location of choke points, the key time lags, when benefits can manifest, and how well parts of fuel cycles work together. This report summarizes the readiness of existing Fuel Cycle Technology (FCT) tools and data for conducting dynamic analyses on the range of options. VISION is the primary dynamic analysis tool. Not only does it model mass flows, as do other dynamic system analysis models, but it allows users to explore various potential constraints. The only fuel cycle for which constraints are not important are those in concept advocates PowerPoint presentations; in contrast, comparative analyses of fuel cycles must address what constraints exist and how they could impact performance. The most immediate tool need is extending VISION to the thorium/U233 fuel cycle. Depending on further clarification of waste management strategies in general and for specific fuel cycle candidates, waste management sub-models in VISION may need enhancement, e.g., more on 'co-flows' of non-fuel materials, constraints in waste streams, or automatic classification of waste streams on the basis of user-specified rules. VISION originally had an economic sub-model. The economic calculations were deemed unnecessary in later versions so it was retired. Eventually, the program will need to restore and improve the economics sub-model of VISION to at least the cash flow stage and possibly to incorporating cost constraints and feedbacks. There are multiple sources of data that dynamic analyses can draw on. In this report, 'data' means experimental data, data from more detailed theoretical or empirical calculations on technology performance, and assumptions such as the earliest date a technology can be deployed. The only fuel cycles for which we currently have adequate data are those we are sure we will never build, e.g., a PUREX plant in the U.S. For actual candidates, even for once through LWRs, there remain missing data such as how the fuel cycle would be completed with a geologic repository. The most immediate data needs are probably basic reactor physics data for new concepts and data associated with waste management for anything other than current technology. The readiness of tools and data is fluid and depends on what purposes are envisioned to drive upcoming analyses and further definition of the waste-related characteristics of fuel cycle candidates. Tools and data sets evolve as needs evolve. Thus, much of the document explains that if the FCT program wants a certain type of analysis, then the tools and data needs are as indicated. For example, functions can be treated as either commodities or facilities. Reactors, separation, fuel fabrication, repository are treated as facility types. Other functions such as uranium mining, conversion, enrichment, and waste packaging and non-repository disposal are treated as commodities and therefore not modeled as extensively. In summary, the tools are functional and can answer many fuel cycle questions but some analyses will require that the tools be modified to support those analyses.

Steven J. Piet; Nick R. Soelberg

2011-06-01

307

Water-cooled solid-breeder blanket concept for ITER  

SciTech Connect

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

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

1989-03-01

308

Key engineering features of the ITER-FEAT magnet system and implications for the R&D programme  

Microsoft Academic Search

The magnet design of the new ITER-FEAT machine comprises 18 toroidal field (TF) coils, a central solenoid (CS), 6 poloidal field coils and correction coils. A key driver of this new design is the requirement to generate and control plasmas with a relatively high elongation (kappa95 = 1.7) and a relatively high triangularity (delta95 = 0.35). This has led to

M. Huguet

2001-01-01

309

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

310

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

SciTech Connect

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

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

1995-03-01

311

Utility of an on-line computer system in a clinical setting for nutrient intake analyses.  

PubMed

The present report describes a four-week trial at the Victoria General Hospital, Halifax, to determine the effect of access to a computer system on nutrient intake analyses, the problems in implementation of the system, and the response of the staff dietitians. An on-line system was obtained from the Ohio State University Hospitals and modified to reflect Canadian food and nutrient content, and to include some additional program features. Twelve hundred and eighty-six foods were characterized according to 15 food components, the system was responsive to nine interactive commands, and there were nine possible print-out formats of calculations. The results of the trial reinforced the expectation of greatly increased work efficiency, however, the system was not utilized to its potential. Some technical problems were largely overcome within the first week of operation. However, needs relating to the extensiveness of the food and nutrient data base, and the methodologies and time for obtaining and evaluating individual dietary intake information prevented maximum efficiency. The dietitians liked the comprehensiveness and detail of the system, however, routine dietary intake collections were too time-consuming for their present work schedules. PMID:10248685

Kirkcaldy-Hargreaves, M; Casey, A; Hogan, E; Mulroney, R

1980-04-01

312

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

PubMed Central

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

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

2011-01-01

313

Biosphere Modeling and Analyses in Support of Total System Performance Assessment  

SciTech Connect

The Nuclear Waste Policy Act of 1982 established the obligations of and the relationship between the U.S. Environmental Protection Agency (EPA), the U.S. Nuclear Regulatory Commission (NRC), and the U.S. Department of Energy (DOE) for the management and disposal of high-level radioactive wastes. In 1985, the EPA promulgated regulations that included a definition of performance assessment that did not consider potential dose to a member of the general public. This definition would influence the scope of activities conducted by DOE in support of the total system performance assessment program until 1995. The release of a National Academy of Sciences (NAS) report on the technical basis for a Yucca Mountain-specific standard provided the impetus for the DOE to initiate activities that would consider the attributes of the biosphere, i.e. that portion of the earth where living things, including man, exist and interact with the environment around them. The evolution of NRC and EPA Yucca Mountain-specific regulations, originally proposed in 1999, was critical to the development and integration of biosphere modeling and analyses into the total system performance assessment program. These proposed regulations initially differed in the conceptual representation of the receptor of interest to be considered in assessing performance. The publication in 2001 of final regulations in which the NRC adopted standard will permit the continued improvement and refinement of biosphere modeling and analyses activities in support of assessment activities.

Tappen, J. J.; Wasiolek, M. A.; Wu, D. W.; Schmitt, J. F.; Smith, A. J.

2002-02-26

314

Biosphere Modeling and Analyses in Support of Total System Performance Assessment  

SciTech Connect

The Nuclear Waste Policy Act of 1982 established the obligations of and the relationship between the U.S. Environmental Protection Agency (EPA), the U.S. Nuclear Regulatory Commission (NRC), and the U.S. Department of Energy (DOE) for the management and disposal of high-level radioactive wastes. In 1985, the EPA promulgated regulations that included a definition of performance assessment that did not consider potential dose to a member of the general public. This definition would influence the scope of activities conducted by DOE in support of the total system performance assessment program until 1995. The release of a National Academy of Sciences (NAS) report on the technical basis for a Yucca Mountain-specific standard provided the impetus for the DOE to initiate activities that would consider the attributes of the biosphere, i.e. that portion of the earth where living things, including man, exist and interact with the environment around them. The evolution of NRC and EPA Yucca Mountain-specific regulations, originally proposed in 1999, was critical to the development and integration of biosphere modeling and analyses into the total system performance assessment program. These proposed regulations initially differed in the conceptual representation of the receptor of interest to be considered in assessing performance. The publication in 2001 of final regulations in which the NRC adopted standard will permit the continued improvement and refinement of biosphere modeling and analyses activities in support of assessment activities.

Jeff Tappen; M.A. Wasiolek; D.W. Wu; J.F. Schmitt

2001-12-06

315

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

316

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

317

ITER Magnet Feeder: Design, Manufacturing and Integration  

NASA Astrophysics Data System (ADS)

The International Thermonuclear Experimental Reactor (ITER) feeder procurement is now well underway. The feeder design has been improved by the feeder teams at the ITER Organization (IO) and the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) in the last 2 years along with analyses and qualification activities. The feeder design is being progressively finalized. In addition, the preparation of qualification and manufacturing are well scheduled at ASIPP. This paper mainly presents the design, the overview of manufacturing and the status of integration on the ITER magnet feeders. supported by the National Special Support for R&D on Science and Technology for ITER (Ministry of Public Security of the People's Republic of China-MPS) (No. 2008GB102000)

CHEN, Yonghua; ILIN, Y.; M., SU; C., NICHOLAS; BAUER, P.; JAROMIR, F.; LU, Kun; CHENG, Yong; SONG, Yuntao; LIU, Chen; HUANG, Xiongyi; ZHOU, Tingzhi; SHEN, Guang; WANG, Zhongwei; FENG, Hansheng; SHEN, Junsong

2015-03-01

318

On the safety of ITER accelerators  

PubMed Central

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

319

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

320

IAEA coordinated research project on 'analytical and experimental benchmark analyses of accelerator driven systems'  

SciTech Connect

This paper provides the general background and the main specifications of the benchmark exercises performed within the framework of the IAEA Coordinated Research Project (CRP) on Analytical and Experimental Benchmark Analyses of Accelerator Driven Systems. The overall objective of the CRP, performed within the framework of the Technical Working Group on Fast Reactors (TWG-FR) of IAEA's Nuclear Energy Dept., is to contribute to the generic R and D efforts in various fields common to innovative fast neutron system development, i.e. heavy liquid metal thermal hydraulics, dedicated transmutation fuels and associated core designs, theoretical nuclear reaction models, measurement and evaluation of nuclear data for transmutation, and development and validation of calculational methods and codes. (authors)

Ait-Abderrahim, H. [SCKCEN, Boeretang 200, B-2400 Mol (Belgium); Stanculescu, A. [International Atomic Energy Agency, Wagramerstrasse 5, A-1400 Vienna (Austria)

2006-07-01

321

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

NASA Technical Reports Server (NTRS)

Modifications to the reference concept were studied and the best approaches defined. The impact of the high efficiency multibandgap solar array on the reference concept design is considered. System trade studies for several solid state concepts, including the sandwich concept and a separate antenna/solar concept, are described. Two solid state concepts were selected and a design definition is presented for each. Magnetrons as an alternative to the reference klystrons for dc/RF conversion are evaluated. System definitions are presented for the preferred klystron and solid state concepts. Supporting systems are analyzed, with major analysis in the microwave, structures, and power distribution areas. Results of studies for thermal control, attitude control, stationkeeping, and details of a multibandgap solar cell study are included. Advanced laser concepts and the meteorological effects of a laser beam power transmission concept are considered.

Hanley, G. M.

1981-01-01

322

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

PubMed

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

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

2013-01-01

323

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.

324

Compatibility of ITER scenarios with an all-W wall  

NASA Astrophysics Data System (ADS)

In 2008, ASDEX Upgrade has started its second experimental campaign with full tungsten coverage of the plasma facing components. In the transition from a partially W-coated device (69% tungsten coverage in 2004/2005) to a full tungsten device (since 2007), post campaign analyses show a reduction by an order of magnitude in both the carbon deposition and deuterium retention for the experimental campaigns. Spectroscopic measurements show that the outer divertor is by far the strongest tungsten source region. However, influxes from the outboard limiters are the most important source for the tungsten content in the plasma. The application of ICRH results in large W influxes due to sputtering from light impurities accelerated by electrical fields at the ICRH antennas. In H-mode discharges, ELMs reduce the inward transport of tungsten in the H-mode edge transport barrier. Central heating provided by neutral beams and the upgraded ECRH systems is used to avoid tungsten accumulation in the core of the plasma. Stationary, ITER relevant H-modes (H98 ~ 1, ?N ~ 1.6-2), with W concentrations below 3 × 10-5, were routinely achieved. High performance H-modes have been obtained before the first boronization, achieving H98 = 1.1-1.2 and ?N up to 2.6 as required for advanced scenarios in ITER. Specific ITER studies performed in 2008 include the demonstration of low voltage plasma start-up with ECRH and heating during the current rise to q95 = 3, to achieve a range of plasma inductance of 0.71-0.97. The new results reported here form the basis of further enhancing the operational space of ASDEX Upgrade with the full tungsten wall, preparing for ITER and the ITER-like wall project in JET.

Sips, A. C. C.; Gruber, O.; ASDEX Upgrade Team

2008-12-01

325

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

326

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

SciTech Connect

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

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

1995-01-01

327

Key engineering features of the ITER-FEAT magnet system and implications for the R&D programme  

NASA Astrophysics Data System (ADS)

The magnet design of the new ITER-FEAT machine comprises 18 toroidal field (TF) coils, a central solenoid (CS), 6 poloidal field coils and correction coils. A key driver of this new design is the requirement to generate and control plasmas with a relatively high elongation (?95 = 1.7) and a relatively high triangularity (?95 = 0.35). This has led to a design where the CS is vertically segmented and self-standing and the TF coils are wedged along their inboard legs. Another important design driver is the requirement to achieve a high operational reliability of the magnets, and this has resulted in several unconventional designs, and in particular the use of conductors supported in radial plates for the winding pack of the TF coils. A key mechanical issue is the cyclic loading of the TF coil cases due to the out-of-plane loads which result from the interaction of the TF coil current and the poloidal field. These loads are resisted by a combination of shear keys and `pre-compression' rings able to provide a centripetal preload at assembly. The fatigue life of the CS conductor jacket is another issue, as it determines the CS performance in terms of the flux generation. Two jacket materials and designs are under study. Since 1993, the ITER magnet R&D programme has been focused on the manufacture and testing of a CS and a TF model coil. During its testing, the CS model coil has successfully achieved all its performance targets in DC and AC operations. The manufacture of the TF model coil is complete. The manufacture of segments of the full scale TF coil case is another important and successful part of this programme and is near completion. New R&D effort is now being initiated to cover specific aspects of the ITER-FEAT design.

Huguet, M.; ITER Joint Central Team; ITER Home Teams

2001-10-01

328

Modelisation et Analyse des syst`emes: Travail Matlab Prof. R. Sepulchre SYST002  

E-print Network

´esolution, y compris les commandes pour afficher les figures. S´eparer clairement les diff´erentes questions et subdiviser le script Matlab est conseill´ee (voir « rapid code iteration » dans l'aide de Matlab) ; ­ un, chacune ´etant capable de d´etecter des vibrations dans une plage de fr´equences pr´ecise (voir Fig. 1

Catholique de Louvain, Université

329

System for Automated Geoscientific Analyses (SAGA) v. 2.1.4  

NASA Astrophysics Data System (ADS)

The System for Automated Geoscientific Analyses (SAGA) is an open-source Geographic Information System (GIS), mainly licensed under the GNU General Public License. Since its first release in 2004, SAGA has rapidly developed from a specialized tool for digital terrain analysis to a comprehensive and globally established GIS platform for scientific analysis and modeling. SAGA is coded in C++ in an object oriented design and runs under several operating systems including Windows and Linux. Key functional features of the modular organized software architecture comprise an application programming interface for the development and implementation of new geoscientific methods, an easily approachable graphical user interface with many visualization options, a command line interpreter, and interfaces to scripting and low level programming languages like R and Python. The current version 2.1.4 offers more than 700 tools, which are implemented in dynamically loadable libraries or shared objects and represent the broad scopes of SAGA in numerous fields of geoscientific endeavor and beyond. In this paper, we inform about the system's architecture, functionality, and its current state of development and implementation. Further, we highlight the wide spectrum of scientific applications of SAGA in a review of published studies with special emphasis on the core application areas digital terrain analysis, geomorphology, soil science, climatology and meteorology, as well as remote sensing.

Conrad, O.; Bechtel, B.; Bock, M.; Dietrich, H.; Fischer, E.; Gerlitz, L.; Wehberg, J.; Wichmann, V.; Böhner, J.

2015-02-01

330

Long-term analyses in automated electrophoretic analyzer in hydrodynamically closed separation system.  

PubMed

Some potential problems that can occur during the analyses of complex samples by on-line combination of capillary isotachophoresis-capillary zone electrophoresis (cITP-CZE) in automated electrophoretic analyzer with the column-coupling configuration of the separation unit were studied in this work. The main focus was devoted on the reproducibility of important analytes' parameters (migration time, peak height and peak area) and also on the stability studies of selected low and high molecular mass analytes of inorganic/organic origins (bromate, vitamins, proteins) present at low concentration levels in different kinds of matrices (mineral water, human urine). Such study was carried out for the first time for the electrophoretic analyzer operating in the hydrodynamically closed separation system provided with contact-less conductivity detectors and UV detector in CZE step. Hydrodynamic and electroosmotic flows of the buffer solutions were suppressed and therefore, only the electrophoretic transport of ions was significant. Obtained results showed the different stabilities of the analytes and samples depending on their origin. The focus in the long-term analyses should be paid on the storage of the samples and on the regular changing the contents of electrolyte vessels to keep the electrolyte composition and separation conditions as constant as possible. PMID:25818560

Sta?ová, Andrea Vojs; Hrenáková, Martina; Marák, Jozef

2015-05-01

331

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

NASA Astrophysics Data System (ADS)

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

Schultz, Colin

2012-04-01

332

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

333

Distinct Signaling Roles of Ceramide Species in Yeast Revealed Through Systematic Perturbation and Systems Biology Analyses  

PubMed Central

Ceramide, the central molecule of sphingolipid metabolism, is an important bioactive molecule participating in cellular regulatory events and having implications for disease. A challenge in deciphering ceramide signaling emanates from the myriad of ceramide species that exist and the possibility that many of them may have distinct functions. Here, we applied systems biology and molecular approaches to perturb ceramide metabolism in the yeast (Saccharomyces cerevisiae) and inferred causal relationships between ceramide species and their potential targets by combining lipidomic, genomic, and transcriptomic analyses. We find that during heat stress distinct metabolic mechanisms control the abundance of different groups of ceramide species. Additionally, distinct groups of ceramide species regulated different sets of functionally related genes, indicating that specific sub-groups of lipids participated in different regulatory pathways. These results indicate a previously unrecognized complexity and versatility of lipid-mediated cell regulation. PMID:24170935

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

2014-01-01

334

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

335

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

336

Progress of IRSN R&D on ITER Safety Assessment  

NASA Astrophysics Data System (ADS)

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

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

2012-08-01

337

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

SciTech Connect

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

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

2012-05-01

338

Iteration, Not Induction  

ERIC Educational Resources Information Center

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

Dobbs, David E.

2009-01-01

339

ITER confinement capability  

SciTech Connect

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

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

1990-01-01

340

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

SciTech Connect

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

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

2011-12-23

341

Stimmungen und Erwartungen im System der Märkte : eine Analyse mit DPLS-Modellen = Sentiments and expectations in the system of markets : an analysis with DPLS models  

Microsoft Academic Search

Diese Forschungsarbeit widmet sich der Analyse von Stimmungen und Erwartungen im System der Märkte mit Dynamic Partial Least Squares (DPLS) Modellen. Die Analyse komplexer Systeme mit umfangreichen Datensätzen und die Erkennung relevanter Muster erfordern die Verwendung moderner statistischer Verfahren. DPLS-Modelle, eine Variante der Strukturgleichungs-modelle mit Latenten Variablen, werden methodisch erweitert, um mehrere zeitliche Verzögerungsstufen gleichzeitig modellieren zu können. Die ökonometrischen

Marcus Ruge

2011-01-01

342

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

NASA Technical Reports Server (NTRS)

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

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

1999-01-01

343

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

NASA Astrophysics Data System (ADS)

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

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

2013-10-01

344

Target organ identification of jellyfish envenomation using systemic and integrative analyses in anesthetized dogs.  

PubMed

Proper treatment of jellyfish envenomed patients can be successfully achieved only from an understanding of the overall functional changes and alterations in physiological parameters under its envenomation. The majority of previous investigations on jellyfish venoms have covered only a couple of parameters at a time. Unlike most other fragmentary jellyfish studies, we employed an integrative toxicological approach, including hemodynamics, clinical chemistry and hematology analyses, using N. nomurai jellyfish venom (NnV) in dogs. After the baseline measurements for mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR), NnV was intravenously administered to the dogs at doses of 0.1 or 0.3mg/kg body weight. The dogs showed significant decreases in MAP (-27.4±3.7 and -48.1±9.9 mmHg), CO (-1.1±0.1 L/min and -1.0±0.2 L/min), and HR (-4.5±0.3 and -9.9±3.1 beats/min) comparing with the respective baseline controls. The onset of systemic hypotension and bradycardia occurred within 1 min of NnV injection and they lasted for 1-35 min, depending on the NnV doses. Interestingly, serum biochemical analyses of envenomed dogs exhibited dramatic increases of alkaline phosphatase (ALP), creatine phosphokinase (CPK), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating its possible target organs. In conclusion, we have demonstrated simultaneously, for the first time, the multiple organ toxicities (cardiotoxic, myotoxic and hepatotoxic) of a scyphozoan jellyfish venom. Based on these results, an integrative toxinological approach using dogs appears to be effective in predicting jellyfish venom toxicities and designing their therapeutic strategies. We expect this method can be applied to other jellyfish venom research as well. PMID:21821138

Kang, Changkeun; Kim, Young Ki; Lee, Hyunkyoung; Cha, Mijin; Sohn, Eun-Tae; Jung, Eun-Sun; Song, Chiyoun; Kim, Minkyung; Lee, Hee Chun; Kim, Jong-Shu; Hwang, Jin-Yong; Yoon, Won Duk; Kim, Euikyung

2011-01-01

345

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

346

Threshold power and energy confinement for ITER  

SciTech Connect

In order to predict the threshold power for L-H transition and the energy confinement performance in ITER, assembling of database and analyses of them have been progressed. The ITER Threshold Database includes data from 10 divertor tokamaks. Investigation of the database gives a scaling of the threshold power of the form P{sub thr} {proportional_to} B{sub t} n{sub e}{sup 0.75} R{sup 2} {times} (n{sub e} R{sup 2}){sup +-0.25}, which predicts P{sub thr} = 100 {times} 2{sup 0{+-}1} MW for ITER at n{sub e} = 5 {times} 10{sup 19} m{sup {minus}3}. The ITER L-mode Confinement Database has also been expanded by data from 14 tokamaks. A scaling of the thermal energy confinement time in L-mode and ohmic phases is obtained; {tau}{sub th} {approximately} I{sub p} R{sup 1.8} n{sub e}{sup 0.4{sub P{sup {minus}0.73}}}. At the ITER parameter, it becomes about 2.2 sec. For the ignition in ITER, more than 2.5 times of improvement will be required from the L-mode. The ITER H-mode Confinement Database is expanded from data of 6 tokamaks to data of 11 tokamaks. A {tau}{sub th} scaling for ELMy H-mode obtained by a standard regression analysis predicts the ITER confinement time of {tau}{sub th} = 6 {times} (1 {+-} 0.3) sec. The degradation of {tau}{sub th} with increasing n{sub e} R{sup 2} (or decreasing {rho}{sub *}) is not found for ELMy H-mode. An offset linear law scaling with a dimensionally correct form also predicts nearly the same {tau}{sub th} value.

Takizuka, T.

1996-12-31

347

Perl Modules for Constructing Iterators  

NASA Technical Reports Server (NTRS)

The Iterator Perl Module provides a general-purpose framework for constructing iterator objects within Perl, and a standard API for interacting with those objects. Iterators are an object-oriented design pattern where a description of a series of values is used in a constructor. Subsequent queries can request values in that series. These Perl modules build on the standard Iterator framework and provide iterators for some other types of values. Iterator::DateTime constructs iterators from DateTime objects or Date::Parse descriptions and ICal/RFC 2445 style re-currence descriptions. It supports a variety of input parameters, including a start to the sequence, an end to the sequence, an Ical/RFC 2445 recurrence describing the frequency of the values in the series, and a format description that can refine the presentation manner of the DateTime. Iterator::String constructs iterators from string representations. This module is useful in contexts where the API consists of supplying a string and getting back an iterator where the specific iteration desired is opaque to the caller. It is of particular value to the Iterator::Hash module which provides nested iterations. Iterator::Hash constructs iterators from Perl hashes that can include multiple iterators. The constructed iterators will return all the permutations of the iterations of the hash by nested iteration of embedded iterators. A hash simply includes a set of keys mapped to values. It is a very common data structure used throughout Perl programming. The Iterator:: Hash module allows a hash to include strings defining iterators (parsed and dispatched with Iterator::String) that are used to construct an overall series of hash values.

Tilmes, Curt

2009-01-01

348

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

ScienceCinema

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

2011-06-03

349

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

350

Reliability studies for the gas-cooled fast breeder reactor residual heat removal systems. Volume II. Details of probabilistic analyses  

SciTech Connect

This report documents a number of probabilistic analyses that have been performed since 1977 on the heat removal trains and electric supplies of the residual heat removal systems in the gas-cooled fast breeder reactor (GCFR). Volume II consists of appendices containing detailed information of those analyses as a backup to the summary descriptions. In the main, the detailed descriptions in this volume have been developed from excerpts from internal memoranda that were prepared at the time the analyses were performed to provide necessary documentation thereof.

Taniguchi, T.; Raabe, P.H.

1980-09-01

351

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

E-print Network

Predictability of European air quality: Assessment of 3 years of operational forecasts and analyses time, the long-term evaluation of an operational real-time air quality forecasting and analysis system between several public organizations. The system forecasts and analyzes air quality throughout Europe

Menut, Laurent

352

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

SciTech Connect

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

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

2012-08-01

353

Core Formation in Planetesimals: Textural Analyses From 3D Synchrotron Imaging and Complex Systems Modeling  

NASA Astrophysics Data System (ADS)

Recent scenarios of core formation in planetesimals using calculations from planetary dynamists and from extinct radionuclides (e.g. 26Al, 60Fe), call for segregation of a metal liquid (core) from both solid silicate and a partially molten silicate - a silicate mush - matrix. These segregation scenarios require segregation of metallic metal along fracture networks or by the growth of molten core material into blebs large enough to overcome the strength of the mush matrix. Such segregation scenarios usually involve high strain rates so that separation can occur, which is in agreement with the accretion model of planetary growth. Experimental work has suggested deformation and shear can help develop fracture networks and coalesce metallic blebs. Here, we have developed an innovative approach that currently combines 2D textures in experimental deformation experiments on a partially molten natural meteorite with complex network analyses. 3D textural data from experimental samples, deformed at high strain rates, with or without silicate melts present, have been obtained by synchrotron-based high resolution hard x-ray microtomography imaging. A series of two-dimensional images is collected as the sample is rotated, and tomographic reconstruction yields the full 3D representation of the sample. Virtual slices through the 3D object in any arbitrary direction can be visualized, or the full data set can be visualized by volume rendering. More importantly, automated image filtering and segmentation allows the extraction of boundaries between the various phases. The volumes, shapes, and distributions of each phase, and the connectivity between them, can then be quantitatively analysed, and these results can be compared to models. We are currently using these new visual data sets to augment our 2D data. These results will be included in our current complex system analytical approach. This integrated method can elucidate and quantify the growth of metallic blebs in regions where a silicate mush matrix is present and help predict separation, in addition to addressing rates and timescales predicted by earlier modelling on silicate-free samples.

Rushmer, T. A.; Tordesillas, A.; Walker, D. M.; Parkinson, D. Y.; Clark, S. M.

2012-12-01

354

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

NASA Astrophysics Data System (ADS)

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

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

2013-11-01

355

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

356

Physics research needs for ITER  

SciTech Connect

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

Sauthoff, N.R.

1995-07-01

357

Analyse de systemes et problemes poses par l'energie solaire  

Microsoft Academic Search

En guise de conclusion, ce bref exposé, ayant pour but de présenter quel peut être le rôle de l'analyse des systèmes dans les études de développement de nouvelles technologies, a je pense montré que :

J. Abatut

358

Use of Time-Aggregated Data in Economic Screening Analyses of Combined Heat and Power Systems  

SciTech Connect

Combined heat and power (CHP) projects (also known as cogeneration projects) usually undergo a series of assessments and viability checks before any commitment is made. A screening analysis, with electrical and thermal loads characterized on an annual basis, may be performed initially to quickly determine the economic viability of the proposed project. Screening analyses using time-aggregated data do not reflect several critical cost influences, however. Seasonal and diurnal variations in electrical and thermal loads, as well as time-of-use utility pricing structures, can have a dramatic impact on the economics. A more accurate economic assessment requires additional detailed data on electrical and thermal demand (e.g., hourly load data), which may not be readily available for the specific facility under study. Recent developments in CHP evaluation tools, however, can generate the needed hourly data through the use of historical data libraries and building simulation. This article utilizes model-generated hourly load data for four potential CHP applications and compares the calculated cost savings of a CHP system when evaluated on a time-aggregated (i.e., annual) basis to the savings when evaluated on an hour-by-hour basis. It is observed that the simple, aggregated analysis forecasts much greater savings (i.e., greater economic viability) than the more detailed hourly analysis. The findings confirm that the simpler tool produces results with a much more optimistic outlook, which, if taken by itself, might lead to erroneous project decisions. The more rigorous approach, being more reflective of actual requirements and conditions, presents a more accurate economic comparison of the alternatives, which, in turn, leads to better decision risk management.

Hudson II, Carl Randy [ORNL

2004-09-01

359

System and Cost Analyses of Broad-Band Fiber Loop Architectures  

Microsoft Academic Search

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

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

1990-01-01

360

U.S. Contributions to ITER  

SciTech Connect

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

Ned R. Sauthoff

2005-05-13

361

Scheduling and rescheduling with iterative repair  

NASA Technical Reports Server (NTRS)

This paper describes the GERRY scheduling and rescheduling system being applied to coordinate Space Shuttle Ground Processing. 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. In this paper we explore the tradeoff between the informedness and the computational cost of several repair heuristics. We show empirically that some knowledge can greatly improve the convergence speed of a repair-based system, but that too much knowledge, such as the knowledge embodied within the MIN-CONFLICTS lookahead heuristic, can overwhelm a system and result in degraded performance.

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

1992-01-01

362

The plasma-facing components transporter (PFCT): A prototype system for PFC replacement on the new ITER 2001 cassette mock-up  

Microsoft Academic Search

Due to major modifications in the ITER 1998 divertor cassette design, the main focus over the past few years has been focussed on the design and manufacture of the various components, devices and tools needed for refurbishment of the new ITER 2001 divertor cassette. The design of this new cassette differs substantially from the earlier version: shape, weight and attachment

G. Miccichè; M. Irving; L. Lorenzelli; L. Muro

2007-01-01

363

Multiple scattering of polarized light in atmosphere- ocean systems: Application to sensitivity analyses of aerosol polarimetry  

NASA Astrophysics Data System (ADS)

Sunlight scattered by small particles in the atmosphere becomes partially polarized, the degree and state of which are sensitive to the physical and chemical properties of these particles. The high accuracy with which these polarization quantities can be measured causes space-borne polarimetry to be a promising remote sensing tool for retrieving tropospheric aerosols, but it also imposes strong requirements on the accuracy and efficiency of the methods used to numerically study such data. Light reflected by the lower atmospheric boundary may, in addition, become highly polarized, necessitating a careful error analysis of the latter scattering contribution to the remotely sensed signal. Part I of this work focusses, on the former requirements for an atmosphere-ocean system, and discusses an approach for treating scattering of light by water body, ocean surface, and atmosphere together in one method while employing numerically efficient techniques for each of these three components. Benchmark results are provided with an accuracy of 5 decimals for the Stokes vectors of scattering contributions to internal and external fields, and we discuss typical features seen in the bidirectional behaviour of the latter contributions. In Part II, we investigate uncertainties in the reflection properties of the ocean system and the resulting variation in degree of linear polarization observed from space. Three sources of uncertainty are identified: oceanic foam, the ocean surface roughness, and underwater light scattering. The magnitude of the latter two sources are derived from current remote sensing capabilities to retrieve the surface windspeed and oceanic pigment concentration, respectively. Simulations are carried out for the visible and near infrared part of the spectrum and two aerosol models. Our analyses indicate that the use of a priori information on the state of the ocean can provide enough constraints for aerosol polarimetry to be sufficiently accurate for climate research, and they give detailed insight on the optimum viewing geometries required for this purpose. Suggestions are given to constrain uncertainties for the other scattering geometries, and we apply our results to a case-study.

Chowdhary, Jacek

1999-09-01

364

Comprehensive safety analysis code system for nuclear fusion reactors III: Ex-vessel LOCA analyses considering passive safety  

SciTech Connect

Ex-vessel loss-of-coolant accidents (LOCAs) in a fusion reactor have been analyzed to investigate the possibility of passive plasma shutdown. For this purpose, a hybrid code of the plasma dynamics and thermal characteristics of the reactor structures, which has been modified to include the impurity emission from plasma-facing components (PFCs), has been developed. Ex-vessel LOCAs of the cooling system during the ignition operation in the International Thermonuclear Experimental Reactor (ITER), in which graphite PFCs were employed in conceptual design activity, were assumed. When double-ended break occurs at the cold leg of the divertor cooling system, the copper cooling tube begins to melt within 3 s after the LOCA, even though the plasma is passively shut down at nearly 4 s. An active plasma shutdown system will be needed for such rapid transient accidents. On the other hand, when a small (1%) break LOCA occurs there, the plasma is passively shut down at nearly 36 s, which happens before the copper cooling tube begins to melt. When the double-ended break LOCA occurs at the cold leg of the first-wall cooling system, there is enough time (nearly 100 s) to shut down the plasma with a controllable method before the reactor structures are damaged. 21 refs., 8 figs.

Honda, T.; Okazaki, T.; Maki, K.; Uda, T. [Hitachi Ltd., Ibaraki (Japan); Seki, Y.; Aoki, I.; Kunugi, T. [Japan Atomic Energy Research Inst., Ibaraki (Japan)

1996-01-01

365

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

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

1990-09-01

366

ITER Project Status Positioning the US  

E-print Network

/30/04 #12;Last time at FESAC: Overview of NSSG-Groups Area US emphasis · Management Structure effectiveness of the funds #12;ITER value is about 50% in "high-tech systems" TF Coils and Structure 10% PF/CS/CC 4% Nb3Sn injector Tritium Tokamak exhaust processing system Ion Cyclotron system 44% of antenna + all transmission

367

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

368

The design of functional materials for genomic and proteomic analyses in microscale systems has begun to mature, from  

E-print Network

in speeding up the sequencing of the first human genome [2]. This accomplishment would have required many more87 The design of functional materials for genomic and proteomic analyses in microscale systems has for microfluidic-based or `chip-based' platforms. In particular, recent research has focused on evaluating

Barron, Annelise E.

369

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...

370

ASDEX Upgrade enhancements in view of ITER application  

Microsoft Academic Search

The aim of the ASDEX Upgrade (AUG) programme is to support the design, prepare the physics base and develop regimes beyond the baseline of ITER and for DEMO. Its ITER-like geometry, poloidal field system, versatile heating system and power fluxes make AUG particularly suited.After the transition to fully tungsten coated plasma facing components AUG could be operated without prior boronizations

O. Gruber

2009-01-01

371

Magnet design technical report---ITER definition phase  

SciTech Connect

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

Henning, C. (ed.)

1989-04-28

372

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

373

Simulation and Analysis of the Hybrid Operating Mode in ITER  

SciTech Connect

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

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

2005-09-22

374

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

375

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

376

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

Microsoft Academic Search

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

Wilhelmshöher Allee; Paul Hildebrandt

2007-01-01

377

International Thermonuclear Experimental Reactor (ITER) neutral beam design  

SciTech Connect

This report discusses the following topics on ITER neutral beam design: ion dump; neutralizer and module gas flow analysis; vacuum system; cryogenic system; maintainability; power distribution; and system cost.

Myers, T.J.; Brook, J.W.; Spampinato, P.T.; Mueller, J.P.; Luzzi, T.E.; Sedgley, D.W. (Grumman Corp., Bethpage, NY (USA). Space Systems Div.)

1990-10-01

378

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 M(k). 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 R(k), 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

379

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

SciTech Connect

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

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

2009-11-26

380

Final Report on ITER Task Agreement 81-18  

SciTech Connect

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

Brad J. Merrill

2008-02-01

381

Iterative calculations of dielectric eigenvalue spectra  

Microsoft Academic Search

The eigenvalues and eigenvectors of the dielectric matrix gamma provide a compact representation of the screening properties of interacting electronic systems. We have previously shown that the dielectric eigenvalue spectrum may be efficiently computed by iterative linear-response calculations and that for nonmetallic systems gamma may be obtained through an eigenvalue-eigenvector decomposition where only a small number of eigenvalues are included.

Hugh F. Wilson; Deyu Lu; François Gygi; Giulia Galli

2009-01-01

382

White paper for Developing an Advanced Fueling System and for supporting Disruption Mitigation studies for ITER on NSTX-U  

E-print Network

White paper for Developing an Advanced Fueling System and for supporting 2012) 1/3 White Paper for Developing Advanced Fueling System-mails: raman@aa.washington.edu , Jarboe@aa.washington.edu , nelson@ee.washington.edu This white

383

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

Microsoft Academic Search

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

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

2001-01-01

384

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

385

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

386

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

USGS Publications Warehouse

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

Baedecker, P.A.

1977-01-01

387

Application of time-series analyses to the hydrological functioning of an Alpine karstic system Hydrology and Earth System Sciences, 8(6), 10511064 (2004) EGU  

E-print Network

Application of time-series analyses to the hydrological functioning of an Alpine karstic system is based on time-series analysis, from classical to more detailed techniques. The simple cross-correlation of the functioning of karstic systems. Simple correlation analysis characterises the individual structure of the time

Paris-Sud XI, Université de

388

CAD Development Design Iterative  

E-print Network

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

Krovi, Venkat

389

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

390

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

PubMed

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

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

2012-07-01

391

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

392

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

USGS Publications Warehouse

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

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

2001-01-01

393

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

394

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

395

Department of Energy ITER Project  

E-print Network

Department of Energy Assessment of the ITER Project Cost Estimate November 2002 #12;ii #12;i EXECUTIVE SUMMARY The Department of Energy (DOE) Assessment of the ITER Project Cost Estimate was conducted by the ITER Team, emphasizing reasonableness of project cost and schedule assumptions and, to the extent

396

[Iterative dysarthria in Parkinson disease].  

PubMed

Iterative dysarthria is a speech disorder which bears some resemblance to stuttering. It is commonly found in Parkinson's disease but has so far received little attention to. We report the case of a 67 year old female parkinsonian patient with a severe dysarthria of the iterative type. The characteristic features of iterative dysarthria are described and the relevant literature is reviewed. PMID:3054596

Machetanz, J; Schönle, P W; Benecke, R

1988-09-01

397

ITER activities and fusion technology  

Microsoft Academic Search

At the 21st IAEA Fusion Energy Conference, 68 and 67 papers were presented in the categories of ITER activities and fusion technology, respectively. ITER performance prediction, results of technology R&D and the construction preparation provide good confidence in ITER realization. The superconducting tokamak EAST achieved the first plasma just before the conference. The construction of other new experimental machines has

M. Seki

2007-01-01

398

JET-EP ITER-like ICRF antenna  

Microsoft Academic Search

Whereas the essential components for power generation and transmission on an ITER-sized ICRF plant are readily available, or only require modest extrapolation of present day ICRF systems, the IC launching structure itself is regarded as needing development, validation and convincing demonstration. During the ITER-EDA, the design requirements of the Next Step device have resulted in increasingly higher values for this

F. Durodié; P. Lamalle; G. Agarici; G. Amarante; W. Baity; B. Beaumont; S. Brémond; L. Colas; J. Fanthome; R. Goulding; R. Koch; A. Kaye; G. Mazzone; J.-M. Noterdaeme; Y. Pouleur; V. Riccardo; M. Roccella; C. Sborchia; A. Sibley; P. Testoni; P. Tigwell; K. Vulliez; R. Walton

2001-01-01

399

Fast Ion Collective Thomson Scattering Diagnostic for ITER  

E-print Network

Fast Ion Collective Thomson Scattering Diagnostic for ITER P.K. Michelsen, H. Bindslev, S. Korsholm of fast ions in ITER has been performed. The system is based on two high power probe beams the fast ion distribution from 100 keV to 3.5 MeV with a time resolution of 100 ms and a spatial resolution

400

Reliability of iterative linear equation solvers in chemical process simulation  

Microsoft Academic Search

For large-scale problems, it may be attractive to use iterative methods to solve the large, sparse, linear systems that arise in the equation-based approach to process simulation. This is because, as problem sizes grow, direct methods become extremely expensive in terms of both computation time and storage requirements. Iterative methods, however, may not be reliable for the indefinite and highly

H. N. Cofer; M. A. Stadtherr

1996-01-01

401

FUELING OF ITER-SCALE FUSION PLASMAS M. J. Gouge  

E-print Network

FUELING OF ITER-SCALE FUSION PLASMAS M. J. Gouge Oak Ridge National Laboratory P. O. Box 2009 Oak Ridge, Tennessee 37831-8071, USA (423) 576-4467 ABSTRACT Fueling system functions for the International Thermonuclear Engineering Reactor (ITER) and similar scale devices are to provide hydrogenic fuel to maintain

402

Global Asymptotic Behavior of Iterative Implicit Schemes  

NASA Technical Reports Server (NTRS)

The global asymptotic nonlinear behavior of some standard iterative procedures in solving nonlinear systems of algebraic equations arising from four implicit linear multistep methods (LMMs) in discretizing three models of 2 x 2 systems of first-order autonomous nonlinear ordinary differential equations (ODEs) is analyzed using the theory of dynamical systems. The iterative procedures include simple iteration and full and modified Newton iterations. The results are compared with standard Runge-Kutta explicit methods, a noniterative implicit procedure, and the Newton method of solving the steady part of the ODEs. Studies showed that aside from exhibiting spurious asymptotes, all of the four implicit LMMs can change the type and stability of the steady states of the differential equations (DEs). They also exhibit a drastic distortion but less shrinkage of the basin of attraction of the true solution than standard nonLMM explicit methods. The simple iteration procedure exhibits behavior which is similar to standard nonLMM explicit methods except that spurious steady-state numerical solutions cannot occur. The numerical basins of attraction of the noniterative implicit procedure mimic more closely the basins of attraction of the DEs and are more efficient than the three iterative implicit procedures for the four implicit LMMs. Contrary to popular belief, the initial data using the Newton method of solving the steady part of the DEs may not have to be close to the exact steady state for convergence. These results can be used as an explanation for possible causes and cures of slow convergence and nonconvergence of steady-state numerical solutions when using an implicit LMM time-dependent approach in computational fluid dynamics.

Yee, H. C.; Sweby, P. K.

1994-01-01

403

ECCD Simulations of ITER Steady State Scenarions  

NASA Astrophysics Data System (ADS)

The ability of ITER electron cyclotron (EC) launchers to achieve current profile control is analyzed and the implications of existing models in the ITER steady-state regime are examined. EC current drive (CD) deposited at mid radius is needed to form a weak reverse shear profile, supplementing off-axis neutral beam injection. Modification of the equatorial and upper launcher design with steering poloidal angles at larger toroidal angles could drive substantial current at mid to outer radii with good efficiency. Implications of the modified ECCD on ITER steady-state scenarios are examined using an iterative steady-state solution procedure using FASTRAN solver self-consistently with heating and CD, MHD equilibrium, and transport models. The modeling uses a range of theory-based transport models (GLF23, TGLF, CDBM, etc.); edge pedestal/boundary conditions (experimental, EPED); plasma current, and plasma density. The objective of the exercise is to understand the range of steady state solutions that the ITER heating and current drive systems may yield, or conditions under which they may be applied.

Murakami, M.; Park, J. M.; Rasmussen, D. A.; Prater, R.; Luce, T. C.; Snyder, P. B.; Henderson, M.

2012-10-01

404

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

405

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

406

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

Microsoft Academic Search

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

Ming Zheng; Graham T. Reader

2004-01-01

407

A multi-agent system of evidential reasoning for intelligence analyses  

Microsoft Academic Search

This paper describes a Multi-Agent System intended for assisting military commanders and intelligence analysts in the discovery and analysis of publicly available information that may have intelligence value (Open Source Intelligence, or OSINT). Our system is called Webster, which is a pun on the well-known dictionary and the World Wide Web. An innovative feature of Webster is the trust network

Eric Lindahl; Stephen O'hara; Qiuming Zhu

2007-01-01

408

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

SciTech Connect

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

Baring-Gould, I.

2009-04-01

409

Functions of the Performance Appraisal System: Analyses and their Impact on Level of Employees’ Motivation  

Microsoft Academic Search

In this paper, the authors integrate the analysis of functions of the performance appraisal system and research of their impact on the level of employees’ motivation in the institutions of Bosnia and Herzegovina. They start from the assumption that the purpose of effective performance appraisal system is reflected in linking employees’ activities through the stabilization function and documentary function, using

Bahrija Umihanic; Mirela Cebic

2012-01-01

410

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

411

Three-dimensional imaging system for analyses of dynamic droplet impaction and deposition formation on leaves  

Technology Transfer Automated Retrieval System (TEKTRAN)

A system was developed to assess the dynamic processes of droplet impact, rebound and retention on leaf surfaces with three-dimensional (3-D) images. The system components consisted of a uniform-size droplet generator, two high speed digital video cameras, a constant speed track, a leaf holder, and ...

412

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...

413

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

PubMed

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

Lee, S; Kim, H-J

2014-05-01

414

SCALE: A modular code system for performing standardized computer analyses for licensing evaluation: Functional modules, F9-F11  

SciTech Connect

This Manual represents Revision 5 of the user documentation for the modular code system referred to as SCALE. The history of the SCALE code system dates back to 1969 when the current Computational Physics and Engineering Division at Oak Ridge National Laboratory (ORNL) began providing the transportation package certification staff at the U.S. Atomic Energy Commission with computational support in the use of the new KENO code for performing criticality safety assessments with the statistical Monte Carlo method. From 1969 to 1976 the certification staff relied on the ORNL staff to assist them in the correct use of codes and data for criticality, shielding, and heat transfer analyses of transportation packages. However, the certification staff learned that, with only occasional use of the codes, it was difficult to become proficient in performing the calculations often needed for an independent safety review. Thus, shortly after the move of the certification staff to the U.S. Nuclear Regulatory Commission (NRC), the NRC staff proposed the development of an easy-to-use analysis system that provided the technical capabilities of the individual modules with which they were familiar. With this proposal, the concept of the Standardized Computer Analyses for Licensing Evaluation (SCALE) code system was born. This volume consists of the section of the manual dealing with three of the functional modules in the code. Those are the Morse-SGC for the SCALE system, Heating 7.2, and KENO V.a. The manual describes the latest released versions of the codes.

NONE

1997-03-01

415

ITER breeding blanket design  

SciTech Connect

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

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

1995-12-31

416

Iterative Space-Time Adaptive Processing  

Microsoft Academic Search

To reduce the need of secondary data and\\/or accurate prior knowledge of the clutter statistics in space-time adaptive processing (STAP), we present herein a user parameter-free and secondary data-free fully automatic weighted least squares based iterative adaptive approach (IAA) to angle-Doppler imaging for airborne surveillance radar systems.

J. Li; X. Zhu; P. Stoica; M. Rangaswamy

2009-01-01

417

Scheduling Optimization Through Iterative Renemen t  

Microsoft Academic Search

Scheduling computations with communications is the theoretical basis for achiev- ing ecien t parallelism on distributed memory systems. We generalize Graham's task-level in a manner to incorporate the eects of computation and communication. A new scheduling is proposed by combining task priority with ecien t management of processor idle time. We also propose an optimization called Iterative Renemen t Scheduling

Mayez Al-Mouhamed; Adel Al-Massarani

418

Symmetric iterative interpolation processes  

Microsoft Academic Search

Using a baseb and an even number of knots, we define a symmetric iterative interpolation process. The main properties of this process come from an associated functionF. The basic functional equation forF is thatF(t\\/b)=snF(n\\/b)F(t-n). We prove thatF is a continuous positive definite function. We find almost precisely in which Lipschitz classes derivatives ofF belong. If a functiony is defined only

Gilles Deslauriers; Serge Dubuc

1989-01-01

419

L'ARCHITECTURE DES SYSTEMES DE CONTROLE DE GESTION : UNE ANALYSE  

E-print Network

systems. Regarding management control literature, two hypotheses may be stated to study the interactions and that their features depend on the manner in which the two systems interact. On the other hand, it may be postulated ces deux phénomènes ont été nombreuses. Le tableau de bord et le balanced scorecard ont été décrits au

Paris-Sud XI, Université de

420

Computer-assisted analyses of the thermodynamic properties of slags in coal-combustion systems  

SciTech Connect

Equations were developed for the analysis of the thermodynamic properties of molten silicate solutions; the equations take into account the unusual concentration and temperature dependence of the solution properties of ordered systems. For binary systems, these equations were coupled with an optimization computer program to analyze all reliable thermodynamic data, including phase diagrams, free energies and enthalpies of formation of compounds, activities of components, enthalpies of mixing, entropies of fusion, miscibility gaps, etc. In this manner, we analyzed data for five binary systems: CaO-SiO/sub 2/, Na/sub 2/O-SiO/sub 2/, CaO-Al/sub 2/O/sub 3/, Na/sub 2/O-Al/sub 2/O/sub 3/, and Al/sub 2/O/sub 3/-SiO/sub 2/. The results of the binary systems were combined, and an analysis done of three ternary systems: CaO-Al/sub 2/O/sub 3/-SiO/sub 2/, Na/sub 2/O-CaO-SiO/sub 2/, and Na/sub 2/O-Al/sub 2/O/sup 3/-SiO/sub 2/. A tentative analysis of the quaternary system, Na/sub 2/O-CaO-Al/sub 2/O/sub 3/-SiO/sub 2/, was also undertaken. 53 references, 51 figures, 3 tables.

Blander, M.; Pelton, A.D.

1983-09-01

421

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

PubMed Central

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

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

2009-01-01

422

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

423

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

424

Systems-Based Analyses of Brain Regions Functionally Impacted in Parkinson's Disease Reveals Underlying Causal Mechanisms  

PubMed Central

Detailed analysis of disease-affected tissue provides insight into molecular mechanisms contributing to pathogenesis. Substantia nigra, striatum, and cortex are functionally connected with increasing degrees of alpha-synuclein pathology in Parkinson's disease. We undertook functional and causal pathway analysis of gene expression and proteomic alterations in these three regions, and the data revealed pathways that correlated with disease progression. In addition, microarray and RNAseq experiments revealed previously unidentified causal changes related to oligodendrocyte function and synaptic vesicle release, and these and other changes were reflected across all brain regions. Importantly, subsets of these changes were replicated in Parkinson's disease blood; suggesting peripheral tissue may provide important avenues for understanding and measuring disease status and progression. Proteomic assessment revealed alterations in mitochondria and vesicular transport proteins that preceded gene expression changes indicating defects in translation and/or protein turnover. Our combined approach of proteomics, RNAseq and microarray analyses provides a comprehensive view of the molecular changes that accompany functional loss and alpha-synuclein pathology in Parkinson's disease, and may be instrumental to understand, diagnose and follow Parkinson's disease progression. PMID:25170892

Emig-Agius, Dorothea; Bessarabova, Marina; Ivliev, Alexander E.; Schüle, Birgit; Alexander, Jeff; Wallace, William; Halliday, Glenda M.; Langston, J. William; Braxton, Scott; Yednock, Ted; Shaler, Thomas; Johnston, Jennifer A.

2014-01-01

425

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

426

SCALE: A modular code system for performing standardized computer analyses for licensing evaluation: Control modules C4, C6  

SciTech Connect

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

NONE

1997-03-01

427

Web-based applications for building, managing and analysing kinetic models of biological systems  

PubMed Central

Mathematical modelling and computational analysis play an essential role in improving our capability to elucidate the functions and characteristics of complex biological systems such as metabolic, regulatory and cell signalling pathways. The modelling and concomitant simulation render it possible to predict the cellular behaviour of systems under various genetically and/or environmentally perturbed conditions. This motivates systems biologists/bioengineers/bioinformaticians to develop new tools and applications, allowing non-experts to easily conduct such modelling and analysis. However, among a multitude of systems biology tools developed to date, only a handful of projects have adopted a web-based approach to kinetic modelling. In this report, we evaluate the capabilities and characteristics of current web-based tools in systems biology and identify desirable features, limitations and bottlenecks for further improvements in terms of usability and functionality. A short discussion on software architecture issues involved in web-based applications and the approaches taken by existing tools is included for those interested in developing their own simulation applications. PMID:18805901

Saha, Rajib; Yusufi, Faraaz Noor Khan; Park, Wonjun; Karimi, Iftekhar A.

2009-01-01

428

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

NASA Technical Reports Server (NTRS)

A method is developed for predicting the radiant heat flux distribution produced by tungsten filament, tubular fused-quartz envelope heating systems with reflectors. The method is an application of Monte Carlo simulation, which takes the form of a random walk or ray tracing scheme. The method is applied to four systems of increasing complexity, including a single lamp without a reflector, a single lamp with a Hat reflector, a single lamp with a parabolic reflector, and up to six lamps in a six-lamp contoured-reflector heating unit. The application of the Monte Carlo method to the simulation of the thermal radiation generated by these systems is discussed. The procedures for numerical implementation are also presented. Experiments were conducted to study these quartz heating systems and to acquire measurements of the corresponding empirical heat flux distributions for correlation with analysis. The experiments were conducted such that several complicating factors could be isolated and studied sequentially. Comparisons of the experimental results with analysis are presented and discussed. Good agreement between the experimental and simulated results was obtained in all cases. This study shows that this method can be used to analyze very complicated quartz heating systems and can account for factors such as spectral properties, specular reflection from curved surfaces, source enhancement due to reflectors and/or adjacent sources, and interaction with a participating medium in a straightforward manner.

Turner, Travis L.; Ash, Robert L.

1994-01-01

429

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

SciTech Connect

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

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

2007-09-28

430

Analysing the Low Quality of the Data in Lighting Control Systems  

NASA Astrophysics Data System (ADS)

Energy efficiency represents one of the main challenges in the engineering field, i.e., by means of decreasing the energy consumption due to a better design minimising the energy losses. This is particularly true in real world processes in the industry or in business, where the elements involved generate data full of noise and biases. In other fields as lighting control systems, the emergence of new technologies, as the Ambient Intelligence can be, degrades the quality data introducing linguistic values. The presence of low quality data in Lighting Control Systems is introduced through an experimentation step, in order to realise the improvement in energy efficiency that its of managing could afford. In this contribution we propose, as a future work, the use of the novel genetic fuzzy system approach to obtain classifiers and models able to deal with the above mentioned problems.

Villar, Jose R.; de La Cal, Enrique; Sedano, Javier; García-Tamargo, Marco

431

Accelerating Large Scale Image Analyses on Parallel, CPU-GPU Equipped Systems  

PubMed Central

The past decade has witnessed a major paradigm shift in high performance computing with the introduction of accelerators as general purpose processors. These computing devices make available very high parallel computing power at low cost and power consumption, transforming current high performance platforms into heterogeneous CPU-GPU equipped systems. Although the theoretical performance achieved by these hybrid systems is impressive, taking practical advantage of this computing power remains a very challenging problem. Most applications are still deployed to either GPU or CPU, leaving the other resource under- or un-utilized. In this paper, we propose, implement, and evaluate a performance aware scheduling technique along with optimizations to make efficient collaborative use of CPUs and GPUs on a parallel system. In the context of feature computations in large scale image analysis applications, our evaluations show that intelligently co-scheduling CPUs and GPUs can significantly improve performance over GPU-only or multi-core CPU-only approaches. PMID:25419545

Teodoro, George; Kurc, Tahsin M.; Pan, Tony; Cooper, Lee A.D.; Kong, Jun; Widener, Patrick; Saltz, Joel H.

2014-01-01

432

Large-Scale Evolutionary Analyses on SecB Subunits of Bacterial Sec System  

PubMed Central

Protein secretion systems are extremely important in bacteria because they are involved in many fundamental cellular processes. Of the various secretion systems, the Sec system is composed of seven different subunits in bacteria, and subunit SecB brings secreted preproteins to subunit SecA, which with SecYEG and SecDF forms a complex for the translocation of secreted preproteins through the inner membrane. Because of the wide existence of Sec system across bacteria, eukaryota, and archaea, each subunit of the Sec system has a complicated evolutionary relationship. Until very recently, 5,162 SecB sequences have been documented in UniProtKB, however no phylogenetic study has been conducted on a large sampling of SecBs from bacterial Sec secretion system, and no statistical study has been conducted on such size of SecBs in order to exhaustively investigate their variances of pairwise p-distance along taxonomic lineage from kingdom to phylum, to class, to order, to family, to genus and to organism. To fill in these knowledge gaps, 3,813 bacterial SecB sequences with full taxonomic lineage from kingdom to organism covering 4 phyla, 11 classes, 41 orders, 82 families, 269 genera, and 3,744 organisms were studied. Phylogenetic analysis revealed how the SecBs evolved without compromising their function with examples of 3-D structure comparison of two SecBs from Proteobacteria, and possible factors that affected the SecB evolution were considered. The average pairwise p-distances showed that the variance varied greatly in each taxonomic group. Finally, the variance was further partitioned into inter- and intra-clan variances, which could correspond to vertical and horizontal gene transfers, with relevance for Achromobacter, Brevundimonas, Ochrobactrum, and Pseudoxanthomonas. PMID:25775430

Yan, Shaomin; Wu, Guang

2015-01-01

433

Development of Algorithms and Error Analyses for the Short Baseline Lightning Detection and Ranging System  

NASA Technical Reports Server (NTRS)

NASA, at the John F. Kennedy Space Center (KSC), developed and operates a unique high-precision lightning location system to provide lightning-related weather warnings. These warnings are used to stop lightning- sensitive operations such as space vehicle launches and ground operations where equipment and personnel are at risk. The data is provided to the Range Weather Operations (45th Weather Squadron, U.S. Air Force) where it is used with other meteorological data to issue weather advisories and warnings for Cape Canaveral Air Station and KSC operations. This system, called Lightning Detection and Ranging (LDAR), provides users with a graphical display in three dimensions of 66 megahertz radio frequency events generated by lightning processes. The locations of these events provide a sound basis for the prediction of lightning hazards. This document provides the basis for the design approach and data analysis for a system of radio frequency receivers to provide azimuth and elevation data for lightning pulses detected simultaneously by the LDAR system. The intent is for this direction-finding system to correct and augment the data provided by LDAR and, thereby, increase the rate of valid data and to correct or discard any invalid data. This document develops the necessary equations and algorithms, identifies sources of systematic errors and means to correct them, and analyzes the algorithms for random error. This data analysis approach is not found in the existing literature and was developed to facilitate the operation of this Short Baseline LDAR (SBLDAR). These algorithms may also be useful for other direction-finding systems using radio pulses or ultrasonic pulse data.

Starr, Stanley O.

1998-01-01

434

Parent Stars of Extrasolar Planets VI: Abundance Analyses of 20 New Systems  

E-print Network

The results of new spectroscopic analyses of 20 recently reported extrasolar planet parent stars are presented. The companion of one of these stars, HD 10697, has recently been shown to have a mass in the brown dwarf regime; we find [Fe/H] $= +0.16$ for it. For the remaining sample, we derive [Fe/H] estimates ranging from -0.41 to $+0.37$, with an average value of $+0.18 \\pm 0.19$. If we add the 13 stars included in the previous papers of this series and 6 other stars with companions below the 11 M$_{\\rm Jup}$ limit from the recent studies of Santos et al., we derive $ = +0.17 \\pm 0.20$. Among the youngest stars with planets with F or G0 spectral types, [Fe/H] is systematically larger than young field stars of the same Galactocentric distance by 0.15 to 0.20 dex. This confirms the recent finding of Laughlin that the most massive stars with planets are systematically more metal rich than field stars of the same mass. We interpret these trends as supporting a scenario in which these stars accreted high-Z material after their convective envelopes shrunk to near their present masses. Correcting these young star metallicities by 0.15 dex still does not fully account for the difference in mean metallicity between the field stars and the full parent stars sample. The stars with planets appear to have smaller [Na/Fe], [Mg/Fe], and [Al/Fe] values than field dwarfs of the same [Fe/H]. They do not appear to have significantly different values of [O/Fe], [Si/Fe], [Ca/Fe], or [Ti/Fe], though.

G. Gonzalez; C. Laws; S. Tyagi; B. E. Reddy

2000-10-10

435

Experiments On Iterative Methods And The Fast Multipole Method In Electromagnetic Scattering Calculations  

Microsoft Academic Search

. We describe the iterative solution of dense linear systems arising from a surface integral equation ofelectromagnetic scattering. The complex symmetric version of QMR has been used as an iterative solver togetherwith a sparse approximate inverse preconditioner. The preconditioner is computed using the topological informationfrom the computational mesh. The matrix-vector products are computed with the multilevel fast multipole method.The iterative

Jussi Rahola

1998-01-01

436

Fusion Engineering and Design 82 (2007) 11671173 The ITER CODAC conceptual design  

E-print Network

, Culham Science Centre, Oxon, UK c Plasma Science and Fusion Center, MIT, MA, USA d JAEA-Naka, Ibaraki in normal ITER operation. Interlock Systems protect ITER from potentially damaging operating off, transparent access respecting security, a high experiment data rate and data volume since ITER

Greenwald, Martin

437

MANAGEMENT INFORMATION SYSTEMS AND TECHNOLOGIES: ANALYSING RESEARCH TOPICS IN FRANCE AND BRAZIL  

Microsoft Academic Search

When properly applied and managed, Information Systems (IS) and Information Technologies (IT) provide significant productivity gains, reinvent processes, automate tasks, and support activities that could not possibly be performed without them. They also enable a reduction in operational costs and elimination of unnecessary functions, in addition to enhancing the quickness and accuracy of decisions. IS research is expected to not

Mauricio Gregianin Testa; Edimara Mezzomo Luciano; Henrique Freitas

438

Analysing Third Generation Activity Systems: Labour-Power, Subject Position and Personal Transformation  

ERIC Educational Resources Information Center

Purpose: The purpose of this paper is to describe how Engestrom's "third generation" activity theory, with its emphasis on developing conceptual tools to understand dialogues, multiple perspectives and networks of interacting activity systems, has informed research into professional learning in multiagency service settings in England.…

Daniels, Harry; Warmington, Paul

2007-01-01

439

Solar power satellite. System definition study. Part 1, volume 3: Construction, transportation and cost analyses  

NASA Technical Reports Server (NTRS)

Concepts developed for both LEO and GEO construction of photovoltaic and thermal engine satellites are analyzed. Topics discussed include: satellite construction; crew scheduling; crew jobs and organizations; operator productivity rating; constructability rating; transportation systems for cargo launch, refueling operations, personnel transport, and orbit transfer; collision analysis, cost analysis, and radiation evironment and effects.

1977-01-01

440

Analysing Rough Sets weighting methods for Case-Based Reasoning Systems  

Microsoft Academic Search

Case-Based Reasoning systems retrieve cases using a similarity function based on the K-NN or some derivatives. These functions are sensitive to irrelevant, interacting or noisy features. Many similarity functions weigh the relevance of features to avoid this problem. This article proposes two weighting methods based on Rough Sets theory: Proportional Rough Sets and Dependence Rough Sets. Both weighting methods use

Maria Salamó; Elisabet Golobardes

2002-01-01