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AbstractAbstract
[en] From the complexity of computer programs for the solution of scientific and technical problems results a lot of questions. Typical questions concern the strength and weakness of computer programs, the propagation of incertainties among the input data, the sensitivity of input data on output data and the substitute of complex models by more simple ones, which provide equivalent results in certain ranges. Those questions have a general practical meaning, principle answers may be found by statistical methods, which are based on the Monte Carlo Method. In this report the statistical methods are chosen, described and valuated. They are implemented into the modular program system STAR, which is an own component of the program system RSYST. The design of STAR considers users with different knowledge of data processing and statistics. The variety of statistical methods, generating and evaluating procedures. The processing of large data sets in complex structures. The coupling to other components of RSYST and RSYST foreign programs. That the system can be easily modificated and enlarged. Four examples are given, which demonstrate the application of STAR. (orig.)
[de]
Die Komplexitaet von Rechenprogrammen zur Loesung wissenschaftlich-technischer Probleme gibt zu verschiedenen Fragestellungen Anlass. Typische Fragen betreffen die Staerken und Schwaechen des Rechenprogrammes, die Fortpflanzung von Ungenauigkeiten in den Eingabedaten, den Einfluss einzelner Eingabegroessen auf Ausgabegroessen und den Ersatz komplexer Modelle durch einfachere, die in einem bestimmten Bereich gleichwertige Ergebnisse liefern. Diese Fragen sind von allgemeiner, praktischer Bedeutung. Antworten koennen im Prinzip mit statistischen Methoden gefunden werden, die auf der Monte Carlo Methode basieren und fuer jeden Problemkreis aehnlich ablaufen. In dieser Arbeit werden die statistischen Verfahren gesichtet, bewertet und in dem modularen Programmsystem STAR realisiert, das eine eigenstaendige Komponente des Programmsystems RSYST darstellt. Der Entwurf des STAR-Paketes beruecksichtigt einen heterogenen Benutzerkreis, die Vielfalt statistischer, teilweise konkurrierender Generierungs- und Auswerteverfahren, die Verarbeitung grosser Datenmengen in komplexen Strukturen, die Kopplung zu anderen Komponenten von RSYST und RSYST-Fremden Programmen und eine leichte Aenderbarkeit und Erweiterbarkeit. An Beispielen aus der Reaktorsicherheit, Festigkeitslehre und Energiewirtschaft wird schliesslich die Leistungsfaehigkeit des STAR-Paketes demonstriert. (orig.)Original Title
Entwurf und Implementierung eines modularen Programmsystems zur Durchfuehrung statistischer Analysen
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Jan 1984; 196 p; With 71 refs.; Diss. (Dr.-Ing.).
Record Type
Report
Literature Type
Thesis/Dissertation
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Beck, W.; Schmidt, F.A.R.
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1976
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1976
AbstractAbstract
[en] Several methods of error analysis are presented different from each other with respect to applicability and effort. The advantages of the Monte Carlo method for error analysis in RSYST are shown, and its execution for codes integrated in RSYST and those independent of RSYST with already existing modules is described. By the example of RELAP 3, simulating the behavior of a PWR on loss of coolant, the influence of statistical errors on a safety calculation according to the Monte Carlo method is assessed. The generation of random input data for RELAP 3 or for a pre-defined reactor model and the difficulties occurring in it are illustrated. Further, there are discussed input data and results of the calculation within the frame interesting here. (orig.) 891 RW
[de]
Es werden verschiedene Methoden der Fehleranalyse vorgestellt, die sich in ihrer Anwendbarkeit und Aufwendigkeit unterscheiden. Dabei werden die Vorteile der Monte Carlo Methode zur Fehleranalyse in RSYST aufgezeigt sowie ihre Durchfuehrung bei RSYST-integrierten und RSYST-fremden Programmen mit bereits existierenden Moduln beschrieben. Am Beispiel von RELAP 3, das das Verhalten eines DWR bei Kuehlmittelabsenkung beschreibt, werden die Einfluesse statistischer Fehler auf eine Sicherheitsrechnung nach der Monte Carlo Methode untersucht. Die Erzeugung zufaelliger Eingabedaten fuer RELAP 3 bez. eines vorher definierten Reaktormodells und die dabei aufgetretenen Schwierigkeiten werden erlaeutert. Ferner werden Eingabedaten und Rechenergebnisse im hier interessierenden Rahmen diskutiert. (orig.)Original Title
Monte Carlo Simulation im Rahmen von RSYST. T. 2
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Source
Apr 1976; 61 p
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Report
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Beck, W.; Hausch, H.J.
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1978
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1978
AbstractAbstract
[en] The paper describes a statistical analysis in the RSYST-III program system. Using the example of the BOIL program, it is shown how the effects of inaccurate input data on the output data can be discovered. The existing possibilities of data generation, data handling, and data evaluation are outlined. (orig.)
[de]
Diese Arbeit befasst sich mit der Durchfuehrung einer statistischen Analyse im Programmsystem RSYST-III. Am Beispiel des Rechenprgramms BOIL wird gezeigt, wie man die Auswirkungen unsicherer Eingabedaten auf die Ausgabedaten aufdecken kann. Dabei werden die zur Verfuegung stehenden Datengenerierungs-, Datenverwaltungs- und Auswertemoeglichkeiten erlaeutert. (orig.)Original Title
Statistische Analyse des Programms BOIL in RSYST-III
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Source
Nov 1978; 70 p
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Report
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Wilets, L.; Beck, W.
Washington Univ., Seattle, WA (United States). Dept. of Physics. Funding organisation: USDOE, Washington, DC (United States)1991
Washington Univ., Seattle, WA (United States). Dept. of Physics. Funding organisation: USDOE, Washington, DC (United States)1991
AbstractAbstract
[en] classical many body models supplemented by repulsive momentum-dependent potentials to simulate the Pauli and Heisenberg principles have been use with some success for nuclear and atomic bound state and collision problems. They are capable of describing mean ground state properties, hydrodynamics, shocks (if warranted by the physics), viscosity, correlations, clustering, fragmentation, etc. We have become interested in the Feldmeier Gaussian packet formulation since it is based on a variational principle using trial wave functions. We discuss some limitations of the model and discuss further directions of investigation
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Secondary Subject
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1991; 4 p; 7. winter workshop on nuclear dynamics; Key West, FL (United States); 27 Jan - 2 Feb 1991; CONF-910135--6; CONTRACT FG06-88ER40427; OSTI as DE92015351; NTIS; INIS; US Govt. Printing Office Dep
Record Type
Report
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Conference
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Beck, W.; Schuetzle, R.
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik1976
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik1976
AbstractAbstract
[en] Models and correlations are presented describing slip and entrainment during the refilling phase after a LOCA in a PWR. Their applicability is investigated for a computer program to comprehend the processes in a reactor cooling channel during the refilling phase of the core. The models of Levy provide no realistic data for the problem discussed. Bankoff and Jones seem to predict reasonable results. Their half empirical relation is valid for void fractions α up to α approximately 0.75. Empirical correlations are applicable in smaller α-regions. Some relations cannot be evaluated on account of unknown quantities. When entrainment is concerned, often only the critical gas velocity at the onset is stated. It varies strongly. The correlations, describing the entrainment E, defined by the gas-stream, along the vertical axis z, provide values for E between 0.6 and 0.7 after a characteristic ascent at z = 0.5 - 0.6. Restrictions are frequently unknown. (orig./HP)
[de]
Modelle und Korrelationen zur Beschreibung des Schlupfs und Wassermitrisses in der Wiederauffuellphase nach einem Kuehlmittelverlustunfall in einem DWR werden vorgestellt und auf ihre Verwendbarkeit in einem Rechenprogramm zur Erfassung der Vorgaenge in einem Reaktorkuehlkanal beim Wiederauffuellen des Kerns geprueft. Die Modelle von Levy liefern keine realistischen Werte fuer die vorliegende Konfiguration. Bankoff und Jones scheinen mit ihrer halbempirischen Beziehung fuer Dampfvolumenanteile bis α etwa 0.75 vernuenftige Ergebnisse vorauszusagen. Rein empirische Korrelationen gelten in kleineren α-Bereichen. Einige Beziehungen koennen wegen unbekannter Groessen nicht ausgewertet werden. Beim Wassermitriss wird oft nur die kritische Gasgeschwindigkeit beim Einsetzen des Mitrisses angegeben. Sie variiert sehr stark. Die Korrelationen, die den Wassermitriss E, definiert durch die Gasstroemung entlang der Vertikalen z, beschreiben, liefern nach einem markanten Anstieg bei z = 0,5 - 1 m Werte zwischen E = 0,6 und E = 0,7. Restriktionen sind haeufig nicht bekannt. (orig./HP)Original Title
Literaturrecherche ueber Schlupf und Wassermitriss in einem Reaktorkuehlkanal
Primary Subject
Source
Nov 1976; 69 p; 37 figs.; 1 tab.; 62 refs.
Record Type
Report
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Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Beck, W.; Schmidt, F.
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1978
Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme1978
AbstractAbstract
[en] When building computers, compiling computer codes, and analyzing results of calculations, one has to expect errors to occur which can best be accounted for by means of statistical methods. Fundamental questions and mathematics are the same for allcategories of problems. They are briefly presented. The experience with the application of statistical methods to the analysis of computational results is reported in more detail. By means of examples, it is shown that the methods are generally applicable, provide results which are in agreement with experience, and allow one to make statements which may not or only with difficulties be obtained with non-statistical methods. Some extensions of the currently used methods are proposed. The integration of the method in RSYST is described. This integration makes the methods available for general application to arbitrary codes. (orig.) 891 RW
[de]
Beim Bau von Rechnern, bei der Erstellung von Rechenprogrammen und bei der Analyse von Rechenergebnissen muss man mit Fehlern rechnen, die am besten mit statistischen Methoden erfasst werden koennen. Grundfragestellungen und Mathematik sind fuer alle Problemkreise dieselben. Sie werden kurz dargestellt.Ueber Erfahrungen mit der Anwendung statistischer Methoden auf die Analyse von Rechenergebnissen wird ausfuehrlicher berichtet. An Beispielen wird gezeigt, dass die Methoden allgemein anwendbar sind, mit der Erfahrung uebereinstimmende Ergebnisse liefern und Aussagen erlauben, die mit nichtstatistischen Methoden nicht oder nur schwer zu bekommen sind. Einige Erweiterungen der gegenwaertig verwendeten Methoden werden vorgeschlagen. Die Integration des Verfahrens in RSYST wird beschrieben. Diese Integration macht die Methoden zur allgemeinen Anwendung auf beliebige Programme verfuegbar. (orig.)Original Title
Statistische Fehleranalyse von Rechnern, Rechenprogrammen und Rechenergebnissen
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Source
Feb 1978; 38 p; With figs. and tabs.
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Report
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AbstractAbstract
[en] The input quantities of computer programs within the area of nuclear safety must often be considered as random quantities. From the knowledge of the input performance it is desired to draw conclusions about output performance (e.g.: distributions, confidence bounds, correlations). The application of Monte Carlo methods is introduced and the automatization of probabilistic analysis in program systems is described, based on the experiences in the frame of the modular systems RSYST and SSYST. Furthermore results for various types of nuclear reactor safety calculations are shown
Primary Subject
Source
Anon; p. II.6.1-II.6.11; 1978; p. II.6.1-II.6.11; American Nuclear Society, Inc; La Grange Park, IL; Probabilistic analysis of nuclear reactor safety; Los Angeles, CA, USA; 8 - 10 May 1978
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Book
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AbstractAbstract
[en] We present a Fourier-transform spectroscopic technique for investigation of surfaces and interfaces based on IR-visible sum-frequency generation with femtosecond light pulses. The observed spectrum has a resolution that is independent of the input pulse characteristics. (c) 1999 Optical Society of America
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Journal Article
Literature Type
Numerical Data
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AbstractAbstract
[en] The Halden experiment IFA-560.2 was an experiment in which the corrosion behaviour of PWR fuel rodlets was investigated simultaneously under different load and cooling conditions: Permanent convective cooling at 50% power, permanent nucleate boiling at 100% power and periodic cycling between these two states. The objective was to study possible influences on the corrosion mechanism which might generically be related to the cycling operation. The oxide layer increments after 90 operations days and 60 day/night cycles were evaluated using the Siemens/KWU corrosion model regarding the special thermal hydraulic conditions of the experimental loop. The analysis proves that the layer thickness increases could be described purely following the changes in temperature caused by the power changes. No extra effect due to the frequent changes between the different cooling conditions could be observed. (orig.)
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Extended and updated paper from the 'Annual meeting on nuclear technology '90', Nuernberg (Germany), 15-17 May 1990.
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Journal Article
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Country of publication
ALLOYS, BOILING, CHEMICAL REACTIONS, CHEMISTRY, CHROMIUM ADDITIONS, CONVECTION, CORROSION RESISTANT ALLOYS, ENERGY TRANSFER, ENRICHED URANIUM REACTORS, HEAT RESISTING ALLOYS, HEAT TRANSFER, IRON ADDITIONS, MANAGEMENT, NUCLEAR MATERIALS MANAGEMENT, PHASE TRANSFORMATIONS, POWER REACTORS, REACTORS, THERMAL REACTORS, TIN ALLOYS, WATER COOLED REACTORS, WATER MODERATED REACTORS, ZIRCALOY, ZIRCONIUM ALLOYS, ZIRCONIUM BASE ALLOYS
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AbstractAbstract
[en] The Alcator C-MOD tokamak has been constructed by the Massachusetts Institute of Technology under contract to the U.S. Department of Energy. It is a compact (0.66 m major radius) high field (9 tesla) tokamak designed to produce diverted, elongated plasmas up to 3.0 MA for a flattop of at least one second. The toroidal field magnet is a cryocooled copper magnet incorporating several unique design features. Each rectangular magnet turn comprises four separate components, inner and outer vertical legs, upper and lower radial arms. The inner vertical legs of the magnet are bonded together into a wedged self-supporting unit. The radial arms and outer vertical legs carry the magnetic loads to an external superstructure against which the toroidal magnet forces are reacted. The unique design features are described in detail. The manufacturing processes for the various magnet components are outlined, and the assembly of the toroidal field magnet components into the tokamak
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Anon; 1236 p; ISBN 0-7803-0132-3; ; 1992; p. 292-294; IEEE Service Center; Piscataway, NJ (UNITED STATES); 14. IEEE symposium on fusion engineering; San Diego, CA (United States); 30 Sep - 3 Oct 1991; IEEE Service Center, 445 Hoes Ln., Piscataway, NJ 08854 (UNITED STATES)
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Book
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Conference
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