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  • Opus Repository ZIB  (53)
  • 1985-1989  (53)
  • 1989  (31)
  • 1987  (22)
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  • 1985-1989  (53)
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  • 1
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    A Numerical Algorithm for Computing the Restricted Singular Value Decomposition of Matrix Triplets. (1989)
    Details
    Publication Date: 2014-02-26
    Description: This paper presents a numerical algorithm for computing the restricted singular value decomposition of matrix triplets (RSVD). It is shown that one can use unitary transformations to separate the regular part from a general matrix triplet. After preprocessing on the regular part, one obtains a matrix triplet consisting of three upper triangular matrices of the same dimensions. The RSVD of this special matrix triplet is computed using the implicit Kogbetliantz technique. The algorithm is well suited for parallel computation. {\bf Keywords:} Restricted singular values, matrix triplets, unitary transformations, implicit Kogbetliantz technique.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 2
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    On the Possible Accuracy of TVD Schemes. (1989)
    Details
    Publication Date: 2014-02-26
    Description: The paper presents a detailed analysis of the possible accuracy available for TVD schemes in one dimension with emphasis to the semi-discrete 1-D TVD schemes. The analysis shows that the widely accepted statement [1] of degeneration of accuracy at critical points for TVD schemes should be corrected. We have theorem: TVD schemes using flux limiters $ \varphi $ of the form [1], [2] may be second-order accurate at critical points if $ \varphi $ (3) + $ \varphi $(-1) = 2, but cannot be uniformly second-order accurate in the whole neighborhood of critical point. If $ \varphi $(1) = 1, then the TVD schemes are second-order accurate in the region of smooth solutions sufficiently far from the critical points. Two ways are suggested to improve the accuracy. Numerical example is given. {\bf Keywords:} Semi-discrete schemes, TVD, flux limiter, degeneration of accuracy.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 3
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    Numerical Solution of Multicomponent Alloy Solidification by Multi-Grid Techniques. (1989)
    Details
    Publication Date: 2014-02-26
    Description: The solidification of an $ N $-component alloy is described by an initial boundary value problem for a system of degenerate parabolic equations modelling heat conduction and mass diffusion. Discretizing implicitly in time and by piecewise linear finite elements in the space variables, at each time step the solution of a system of quasivariational inequalities is required. For the numerical solution of that system, a multi-grid algorithm is developed by making use of game theoretic concepts and duality arguments from convex analysis. Finally, the efficiency of the algorithm is demonstrated by displaying numerical results for a ternary alloy.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 4
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    KASKADE Programmer's Manual. (1989)
    Details
    Publication Date: 2014-02-26
    Description: The Programmers Manual contains the documentation of the C-KASKADE implementation. KASKADE is an adaptive finite element code (see SC ). The interfaces of all modules are described.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
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  • 5
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    Implementation of Portable Standard LISP for the SPARC Processor. (1989)
    Details
    Publication Date: 2018-12-06
    Description: The SPARC processor is a RISC (Reduced Instruction Set Computer) microcomputer, built into the SUN4 workstations. Since RISC processors are very well-suited for LISP processing, the implementation of a dialect of LISP (Portable Standard LISP, PSL) boded well for a great speed-up in comparison with other types of microcomputers. A first approach was done at The RAND Corporation in Santa Monica, which was derived from classical processor types like MC68000 or VAX. At the Konrad- Zuse-Zentrum für Informationstechnik Berlin (ZIB) that initial implementation was redesigned in order to adapt PSL to the specific features of the SPARC processor. The present implementation, in some parts, is very close to Cray PSL version also done in ZIB. Some timing informations are given in the appendix.
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    Language: English
    Type: reportzib , doc-type:preprint
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  • 6
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    Trapex in POOL-Implementierung eines numerischen Algorithmus in einer parallelen objektorientierten Sprache. (1989)
    Details
    Publication Date: 2014-02-26
    Description: Die Parallelisierung eines vorhandenen sequentiellen Programmes erfolgt im allgemeinen in der Weise, daß es auf Grund einer Analyse der Datenabhängigkeiten in mehrere parallel ausführbare Teile zerlegt wird, die ihrerseits sequentiell ablaufen und untereinander Daten austauschen. Eine parallele Programmiersprache sollte diese Vorgehensweise unterstützen, indem sie Sprachmittel zur Verfügung stellt, mittels derer sich die Modularisierung und Kommunikation bequem formulieren läßt. Nun läßt sich prinzipiell jede vorhandene sequentielle Programmiersprache um solche Konstrukte erweitern; günstiger in Hinblick auf die Strukturierung eines parallelen Programmes erscheint es aber möglicherweise, eine solche Programmiersprache zu verwenden, die die genannten Konzepte als elementare zur Verfügung stellt. Dies ist offensichtlich bei objektorientierten Programmiersprachen der Fall. Im vorliegenden Bericht wird an Hand eines Beispiels - TRAPEX -, das in POOL-T implementiert wurde, untersucht, inwieweit eine objektorientierte Sprache zur effektiven Programmierung eines numerischen Algorithmus geeignet ist. {\bf Key Words:} parallele objektorientierte Programmiersprache, Message Passing, Abstract Data Typing, Klassenhierarchi, Modul-Import-Mechanismus, Client/Server-Prinzip, Load Balancing, adaptive numerische Algorithmen, Ordnungs- und Schrittweitensteuerung, Romberg-Quadratur.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
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  • 7
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    Numerical Treatment of Implicit Differential Equations and Differential Algebraic Systems (1989)
    Details
    Publication Date: 2020-03-06
    Language: English
    Type: article , doc-type:article
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  • 8
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    Concepts of an adaptive hierarchical finite element code (1989)
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    Publication Date: 2020-03-06
    Language: English
    Type: article , doc-type:article
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  • 9
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    Computational treatment of polyreaction kinetics by orthogonal polynomials of a discrete variable (1989)
    Details
    Publication Date: 2020-03-20
    Language: English
    Type: article , doc-type:article
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  • 10
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    Numerical approaches to treatment planning in deep RF-hyperthermia (1989)
    Details
    Publication Date: 2021-03-16
    Language: English
    Type: article , doc-type:article
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  • 11
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    Via Minimization with Pin Preassignments and Layer Preference (1989)
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    Publication Date: 2014-02-24
    Language: English
    Type: article , doc-type:article
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  • 12
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    Decomposition and Optimization over Cycles in Binary Matroids (1989)
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    Publication Date: 2014-02-24
    Language: English
    Type: article , doc-type:article
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  • 13
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    Master Polytopes for Cycles of Binary Matroids (1989)
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    Publication Date: 2014-02-24
    Language: English
    Type: article , doc-type:article
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  • 14
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    A cutting plane algorithm for a clustering problem (1989)
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    Publication Date: 2014-02-24
    Language: English
    Type: article , doc-type:article
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  • 15
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    Homoclinic Bifurcation at Resonant Eigen-values. (1989)
    Details
    Publication Date: 2014-02-26
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
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  • 16
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    Ein paralleler adaptiver Algorithmus für die numerische Integration. (1989)
    Details
    Publication Date: 2014-02-26
    Description: Der Bericht ist die Ausarbeitung eines Vortrages, der auf dem Transputer Anwender Treffen (TAT'89) im September 1989 gehalten wurde. Es wird die Parallelisierung und Implementierung eines adaptiven Algorithmus zur numerischen Integration (Romberg Quadratur) beschrieben. Ausgewählte Meßergebnisse sind enthalten. {\bf Keywords:} Numerischer Algorithmus, Romberg Quadratur, paralleler adaptiver Algorithmus, dynamische Lastverteilung und Prozessorzahl, lokaler Speicher, Nearest-Neighbour-Architektur, Transputer, TDS, OCCAM2.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
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  • 17
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    Two Preconditioners Based on the Multi-Level Splitting of Finite Element Spaces. (1989)
    Details
    Publication Date: 2014-02-26
    Description: The hierarchical basis preconditioner and the recent preconditioner of BRAMBLE, PASCIAK and XU are derived and analyzed within a joint framework. This discussion elucidates the close relationship between both methods. Special care is devoted to highly nonuniform meshes; our theory is based exclusively on local properties like the shape regularity of the finite elements.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
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  • 18
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    KASKADE User's Manual. (1989)
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    Publication Date: 2014-02-26
    Description: The Users Manual contains an introduction to the usage of the C-KASKADE implementation. KASKADE is an adaptive finite element code (see SC ). The manual includes a description of all commands, a simple recipe to define a new problem by changing the KASKADE source and a complete example.
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    Language: English
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  • 19
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    Numerik von Anfangswertmethoden für gewöhnliche Differentialgleichungen. (1989)
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    Publication Date: 2014-02-26
    Description: Das voliegende Skriptum entstand aus einer Vorlesung, die ich im WS 87/88 an der Freien Universität Berlin im Fachbereich Mathematik gehalten habe. Mein ursprüngliches Vorlesungsmanuskript wurde von Herrn F. Bornemann in weiten Teilen überarbeitet, reorganisiert und substantiell ergänzt. Der Inhalt stammt größtenteils aus Originalarbeiten jüngeren Datums. Darüberhinaus finden sich zahlreiche Teile, die aus meiner jahrelangen Beschäftigung mit dem Thema entstanden aber unpubliziert geblieben sind. Das Skriptum erhebt nicht den Anspruch, ein Lehrbuch zu sein. Es war zunächst als Ausarbeitung für meinen studentischen Hörerkreis sowie als internes Arbeitspapier für das ZIB bestimmt. Die Kunde von der bloßen Existenz eines solchen Skriptums hat jedoch zu einer derart regen Nachfrage geführt, daß es hiermit als Technischer Report des ZIB einer breiteren ffentlichkeit zugänglich gemacht werden soll. In der vorliegenden Form richtet es sich in erster Linie an Mathematiker; es soll sich jedoch auch für Naturwissenschaftler und Ingenieure eignen, die sich einen Einblick in den theoretischen und algorithmischen Hintergrund der von ihnen verwendeten wissenschaftlichen Software verschaffen wollen.
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    Language: German
    Type: reportzib , doc-type:preprint
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  • 20
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    Implementierung des parallelen TRAPEX auf Transputern. (1989)
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    Publication Date: 2014-02-26
    Description: Der folgende Bericht ist eine Ergänzung des ZIB Technical Report TR 88-05. Entsprechend wird hier nicht auf die grundsätzlichen Fragen der Parallelisierbarkeit des sequentiellen TRAPEX eingegangen. Diese sind im TR 88-5 erörtert, die dort beschriebenen Algorithmen (vertikale und horizontale Parallelisierung) werden auch für die Transputerarchitektur verwendet. Meßergebnisse sind im letzten Teil angefügt.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
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  • 21
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    Adaptive Finite-Elemet- Methoden für konvektionsdominierte Randwertprobleme bei partiellen Differentialgleichungen. (1989)
    Details
    Publication Date: 2014-02-26
    Description: Ausgangspunkt bei der Behandlung konvektiv dominierter, elliptischer Probleme sind die bekannten hierarchischen Finite-Element-Methoden für den rein elliptischen Fall. Als stabile Erweiterung des Standard-Galerkin-Verfahrens wird das Stromlinien-Diffusions-Verfahren durch physikalische Überlegungen motiviert und kurz diskutiert. Anschließend zeigen wir, daß diese Methode erst in Verbindung mit einer hier erstmals vorgestellten lokalen Ausrichtung der Kanten wirksam eingesetzt werden kann. Zusammen mit einer ebenfalls neu entwickelten richtungsorientierten Verfeinerungsstrategie erhält man eine erheblich stabilere, genauere und schnellere Auflösung von Grenzschichten als mit herkömmlichen Methoden.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 22
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    Multivariate Rational Interpolation: Reconstruction of Rational Functions. (1989)
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    Publication Date: 2014-02-26
    Description: In this paper we consider the problem of reconstructing a multivariate rational function, when only its values at sufficiently many points are known. We use for the reconstruction of bivariate rational functions a bivariate rational interpolation operator investigated by Siemaszko [7] and a new one, compare both by examples in a Computer Algebra system, and present their multivariate generalizations. {\bf Keywords:} Multivariate rational interpolation, reconstruction, symbolic computation.
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    Language: English
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  • 23
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    Restricted Singular Value Decomposition of Matrix Triplets. (1989)
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    Publication Date: 2014-02-26
    Description: In this paper we introduce the concept of restricted singular values (RSV's) of matrix triplets. A theorem concerning the RSV's of a general matrix triplet $ (A,B,C) $, where $ A \in C^{m\times n} $, $B\in C^{m\times p} $ and $ C\in C^{q\times n} $, which is called restricted singular value decomposition (RSVD) of matrix triplets, is derived. This result generalizes the wellknown SVD, GSVD and the recently proposed product induced SVD (PSVD). Connection of RSV's with the problem of determination of matrix rank under restricted perturbation is also discussed. {\bf Keywords:} Matrix rank, singular values, generalized singular values, product induced singular values, restricted singular values, matrix decompositions.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
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  • 24
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    On Adaptive Grid Refinement in the Presence of Internal or Boundary Layers. (1989)
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    Publication Date: 2014-02-26
    Description: We propose an anisotropic refinement strategy which is specially designed for the efficient numerical resolution of internal and boundary layers. This strategy is based on the directed refinement of single triangles together with adaptive multilevel grid orientation. It is demonstrated by several numerical examples that compared to usual methods, the new anisotropic refinement ends up in more stable and more accurate solutions at much less computational cost. {\bf Keywords:} Adaptive finite elements, directed refinement, adaptive grid orientation, convection diffusion equation, internal and boundary layers.
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    Language: English
    Type: reportzib , doc-type:preprint
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  • 25
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    Computation of Molecular Weight Distributions for Free Radical Polymerization Systems. (1989)
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    Publication Date: 2014-02-26
    Description: Modeling of free radical polymerization leads to very large and usually stiff systems of ordinary differential equations which cannot be solved directly in an efficient way. This paper presents the application of a new approach called discrete Galerkin method to a realistic example - the polymerization of methyl methacrylate(MMA). The method is characterized by a Galerkin approximation on the basis of orthogonal polynomials of a discrete variable which represents the polymer degree. It allows the efficient computation of solutions of complete kinetic schemes with time- or moment-dependent reaction coefficients by reducing the complexity to a few differential equations. The approximation error can be controlled by an error estimation. In the case of MMA polymerization a reduction of computational effort by a factor of about 25 compared to a standard method can be obtained for the quasi-steady-state approximation of the model. In addition solutions of the instationary kinetic scheme can be easily computed.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
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  • 26
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    MmB-A New Class of Accurate High Resolution Schemes for Conservation Laws in Two Dimensions. (1989)
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    Publication Date: 2014-02-26
    Description: In this paper we present the MmB schemes, which preserve the local maximum and minimum bounds of the initial data in the smallest union of mesh elements of previous time step containing the domain of dependence of the solution on the mesh element with center at point $ P $\ under consideration. In 1-D, the MmB schemes are almost identical with TVD schemes. As well-known, there is no second-order TVD scheme in 2-D, nevertheless, we present here two classes of 2-D second-order accurate MmB-schemes. It is proved that 1-D discrete MmB (or TVD) and 1-D semi-discrete TVD schemes may have second-order accuracy at (nonsonic) critical points, but cannot be of uniformly second-order accurate in the whole neighborhood of the critical points. New accurate high resolution flux limiters are suggested. Numerical results for 1-D and 2-D test problems are given. {\bf Keywords:} Difference scheme, TVD, MmB, flux limiter.
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    Language: English
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  • 27
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    CRAY-HANDBUCH. Einführung in die Benutzung der CRAY X-MP unter UNICOS. (veraltet) (1989)
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    Publication Date: 2014-02-26
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
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  • 28
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    Ein Finite-Element-Verfahren zur numerischen Lösung von Erhaltungsgleichungen. (1989)
    Details
    Publication Date: 2021-03-16
    Description: A new approach for the discretisation of hyperbolic conservation laws via a finite element method is developed and analysed. Appropriate forms of the Eulers equation of gas dynamic are considered to employ the algorithm in a reasonable way for this system of nonlinear equations. Both mathematical and physical stability results are obtained. A main part of the paper is devoted to the convergence proof with energy methods under strong regularity of the solution of a scalar nonlinear conservation law. Some hints on the implementation and numerical results for the calculation of transonic gasflow through a Laval nozzle are given. The necessary amount of numerical work is compared to an established finite difference method and the efficiency of the algorithm is shown. A survey on recent literature about finite element methods for hyperbolic problem is included.
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    Language: German
    Type: reportzib , doc-type:preprint
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  • 29
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    Adaptive multilevel discretization in time and space for parabolic partial differential equations. (1989)
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    Publication Date: 2014-02-26
    Description: The present paper developes an adaptive multilevel approach for parabolic PDE's - as a first step, for one linear scalar equation. Full adaptivity of the algorithm is conceptually realized by simultaneous multilevel discretization in both time and space. Thus the approach combines multilevel time discretization, better known as extrapolation methods, and multilevel finite element space discretization such as the hierarchical basis method. The algorithmic approach is theoretically backed by careful application of fundamental results from semigroup theory. These results help to establish the existence of asymptotic expansions (in terms of time-steps) in Hilbert space. Finite element approximation then leads to perturbed expansions, whose perturbations, however, can be pushed below a necessary level by means of an adaptive grid control. The arising space grids are not required to satisfy any quasi- uniformity assumption. Even though the theoretical presentation is independent of space dimension details of the algorithm and numerical examples are given for the 1-D case only. For the 1-D elliptic solver, which is used, an error estimator is established, which works uniformly well for a family of elliptic problems. The numerical results clearly show the significant perspectives opened by the new algorithmic approach.
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  • 30
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    Jahresbericht 1988 (1989)
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    Publication Date: 2019-10-24
    Keywords: ddc:000
    Language: German
    Type: annualzib , doc-type:report
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  • 31
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    Ingenieurmäßige Berechnung der Feldausbreitung in optischen Bauelementen der Lichtwellenleitertechnik (1989)
    Details
    Publication Date: 2022-07-07
    Language: English
    Type: doctoralthesis , doc-type:doctoralThesis
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  • 32
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    A Note on Extrapolation Methods for Second Order ODE Systems. (1987)
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    Publication Date: 2014-02-26
    Description: A slight modification of the extended Stoermer discretization for non self-adjoint second order ODE systems is derived on the basis of a simple stability analysis. This discretization easily extends to implicit ODE systems, which are known to arise e.g. in mechanical engineering. In addition, a special variant of semi-implicit Euler discretization is proposed, which essentially treats the state variables explicitly, but their derivatives implicitly. Numerical tests over critical parameter values of the van der Pol oscillator illustrate the domain of efficiency of the suggested discretizations.
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    Language: English
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  • 33
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    Uniqueness Theorems for Stiff ODE Initial Value Problems. (1987)
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    Publication Date: 2014-02-26
    Description: The paper presents a new uniqueness theory for ODE initial value problems, derived in view of numerical stiff integration. The theory supplies stepsize bounds for stiff integrators that can easily be estimated in extrapolation methods. The additional devices lead to a significant speed-up of computations - in particular in combustion PDE problems.
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    Language: English
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  • 34
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    The Hierarchical Basis Multigrid Method. (1987)
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    Publication Date: 2014-02-26
    Description: We derive and analyze the hierarchical basis-multigrid method for solving discretizations of self-adjoint, elliptic boundary value problems using piecewise linear triangular finite elements. The method is analyzed as a block symmetric Gauß- Seidel iteration with inner iterations, but it is strongly related to 2-level methods, to the standard multigrid V-cycle, and to earlier Jacobi-like hierarchical basis methods. The method is very robust, and has a nearly optimal convergence rate and work estimate. It is especially well suited to difficult problems with rough solutions, discretized using highly nonuniform, adaptively refined meshes.
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    Language: English
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  • 35
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    CGM-Concepts and their Realizations. (1987)
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    Publication Date: 2014-02-26
    Description: Requirements and Design Concepts. Common Graphics Manager (CGM) is the name given to the implementation of GKS, Level 2b, developed at the Free University of Berlin (1,6). This paper is a survey over the "early GKS implementation phase" 1982. Work commenced in February 1980. At the outset some basic design decisions were necessary on account of the special scientific computer environment in Berlin, because the "Berlin GKS" was intended to be a common graphical software package for all the machines.
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    Language: English
    Type: reportzib , doc-type:preprint
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  • 36
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    Preconditioning Indefinite Discretization Matrices. (1987)
    Details
    Publication Date: 2014-02-26
    Description: The finite element discretization of many elliptic boundary value problems leads to linear systems with positive definite and symmetric coefficient matrices. Many efficient preconditioners are known for these systems. We show that these preconditioning matrices can be used also for the linear systems arising from boundary value problems which are potentially indefinite due to lower order terms in the partial differential equation. Our main tool is a careful algebraic analysis of the condition numbers and the spectra of perturbed matrices which are preconditioned by the same matrices as in the unperturbed case. {\bf Keywords: }Preconditioned conjugate gradient methods, finite elements. {\bf Subject Classification: } AMS(MOS):65F10, 65N20, 65N30.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 37
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    Portable Common LISP Subset Implementation for CRAY X+MP Computers. (1987)
    Details
    Publication Date: 2018-12-06
    Description: This document describes the installation procedure and maintenance for the Portable Common LISP Subset (PCLS) developed at the University of Utah.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 38
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    Tätigkeitsbericht 1986 (1987)
    Details
    Publication Date: 2019-10-24
    Keywords: ddc:000
    Language: German
    Type: annualzib , doc-type:report
    Format: application/pdf
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  • 39
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    Efficient numerical pathfollowing beyond critical points (1987)
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    Publication Date: 2020-03-06
    Language: English
    Type: article , doc-type:article
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  • 40
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    Large scale scientific computing. (proceedings of a Meeting on Large Scale Scientific Computing held at the Oberwolfach Mathematical Insitute, Oberwolfach, FRG, July 14-19, 1985) (1987)
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    Publication Date: 2020-03-06
    Language: English
    Type: conferenceobject , doc-type:conferenceObject
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  • 41
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    Numerical Pathfollowing Beyond Critical Points in ODE Models (1987)
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    Publication Date: 2020-03-06
    Language: English
    Type: conferenceobject , doc-type:conferenceObject
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  • 42
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    One-step and extrapolation methods for differential-algebraic systems (1987)
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    Publication Date: 2020-03-06
    Language: English
    Type: article , doc-type:article
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  • 43
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    Extrapolation integrators for quasilinear implicit ODEs. (1987)
    Details
    Publication Date: 2020-12-14
    Language: English
    Type: conferenceobject , doc-type:conferenceObject
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  • 44
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    A Cutting Plane Algorithm for Minimum Perfect 2-Matchings (1987)
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    Publication Date: 2014-02-24
    Language: English
    Type: article , doc-type:article
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  • 45
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    Calculating Exact Ground States of Spin Glasses (1987)
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    Publication Date: 2014-02-24
    Language: English
    Type: conferenceobject , doc-type:conferenceObject
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  • 46
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    The Implementation and Optimization of Portable Standard LISP for the CRAY. (1987)
    Details
    Publication Date: 2018-12-06
    Description: Portable Standard LISP (PSL), a dialect of LISP developed at the University of Utah, has been implemented and optimized for the CRAY 1 and CRAY X-MP supercomputers. This version uses a new implementation technique that permits a step-by-step development of the PSL kernel. The initial CRAY version was acceptable, although the execution speed of the PSL was not as fast as had been anticipated. CRAY-specific optimizations were undertaken that in some cases provided a ten-fold speed improvement, resulting in a fast LISP implementation.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 47
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    Portable Standard LISP Implementation for CRAY X+MP Computers. Release of PSL 3.4 for COS. (1987)
    Details
    Publication Date: 2018-12-06
    Description: Portable Standard LISP (PSL) is a portable implementation of the programming language LISP constructed at the University of Utah. The version 3.4 of PSL was implemented for CRAY X-MP computers by Konrad Zuse-Zentrum Berlin; this implementation is based to an important part on the earlier implementation of PSL 3.2 at Salt Lake City, Los Alamos and Mendota Heights.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 48
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    CRAY-Handbuch. - Einführung in die Benutzung der CRAY. (1987)
    Details
    Publication Date: 2014-03-06
    Description: Das vorliegende Handbuch wendet sich an alle Benutzer des für den Norddeutschen Vektorrechnerverbund im ZIB installierten Rechners CRAY X-MP/24. Ein großer Teil der Darstellung ist der Optimierung von Programmen gewidmet, die in FORTRAN geschrieben sind. Gerade weil die CRAY einer der schnellsten Rechner der Welt ist, wird jeder Benutzer früher oder später selbst auf dieses Thema stoßen, denn die Maschine ist vornehmlich für Probleme bestimmt, die für die meisten anderen Rechner zu komplex sind. Maschinen der CRAY-Leistungsklasse beziehen einen erheblichen Teil ihrer Geschwindigkeit aus der parallelen Arbeit vieler Komponenten. Programme, die die jeweilige Architektur der Maschine berücksichtigen, können um Größenordnungen schneller (also wirtschaftlicher) sein als Programme, deren Autor beim Schreiben einen sogenannten "klassischen" Rechner vor seinem geistigen Auge hatte. Daher wird auch der technische Aufbau der CRAY X-MP im Handbuch erläutert. Weitere Teile des Handbuches beschäftigen sich mit den Vorrechnern und dem Rechnernetz.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 49
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    REDUCE Users Guide for the CRAY 1 / X-MP Series Running COS. Version 3.3. (1987)
    Details
    Publication Date: 2018-12-06
    Description: This document describes operating procedures for running REDUCE specific to the CRAY 1 and CRAY X-MP computers running the CRAY Operating System (COS). The document was derived from the corresponding document for Vax/UNIX prepared by A.C. Hearn and L.R. Seward, The Rand Corporation, Santa Monica, (CP85).
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 50
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    GRAZIL (Graphical ZIB Language). (1987)
    Details
    Publication Date: 2020-03-11
    Description: GRAZIL ist ein interaktives Programmpaket zur graphischen Darstellung von zwei-dimensionalen Kurvenverläufen. Dem Benutzer stehen zahlreiche Kommandos zum Gestalten des Layouts der Zeichnung zur Verfügung. Die Eingabedaten müssen dem ZUGRIFF- Konzept genügen, wodurch die genaue Struktur der Daten erst zur Laufzeit bekannt sein muß und somit eine hohe Flexibilität und eine große Bandbreite der Einsatzmöglichkeiten erreicht wird. GRAZIL wurde mit der graphischen Grundsoftware BIZEPS2 und GKS entwickelt. Dadurch kann ein breites Rechner- und Ausgabegerätespektrum genutzt werden.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 51
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    ZUGRIFF - Eine vereinheitlichte Datenspezifikation für graphische Darstellungen und ihre graphische Aufbereitung. (1987)
    Details
    Publication Date: 2020-03-11
    Description: ZUGRIFF ist eine Dateischnittstelle für Graphikausgabe speziell numerischer Anwenderprogramme. Dieser Report beschreibt den Leistungsumfang der Spezifikation sowie die interaktive graphische Verarbeitung von ZUGRIFF- Dateien.
    Keywords: ddc:000
    Language: German
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 52
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    REDUCE Installation Guide for CRAY 1 / X-MP Systems Running COS. Version 3.3. (1987)
    Details
    Publication Date: 2018-12-06
    Description: This guide describes the CRAY/COS REDUCE distribution tape and the procedures for installing, testing and maintaining REDUCE on a CRAY 1 or CRAY X-MP running COS. This document was derived from the corresponding document for Vax/Unix prepared by A. C. Hearn and L. R. Seward, The Rand Corporation, Santa Monica, publication CP84.
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
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  • 53
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    Besondere Lösungen in harmonisch erregten Ferroresonanz-Kreisen (1987)
    Details
    Publication Date: 2022-07-07
    Language: English
    Type: conferenceobject , doc-type:conferenceObject
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