TY - GEN T1 - Jahresbericht 1989 T3 - Jahresbericht - 1989 KW - Annual Report Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-9847 SN - 0934-5892 ER - TY - GEN A1 - Bornemann, Folkmar A. T1 - An Adaptive Multilevel Approach to Parabolic Equations I. General Theory & 1D-Implementation. N2 - A new adaptive multilevel approach for parabolic PDE's is presented. Full adaptivity of the algorithm is realized by combining multilevel time discretization, better known as extrapolation methods, and multilevel finite element space discretization. In the theoretical part of the paper the existence of asymptotic expansions in terms of time-steps for single-step methods in Hilbert space is established. 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 theoretical presentation is independent of space dimension. In this part I of the paper details of the algorithm and numerical examples are given for the 1D case only. The numerical results clearly show the significant perspectives opened by the new algorithmic approach. T3 - ZIB-Report - SC-90-04 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-320 ER - TY - GEN A1 - Hege, Hans-Christian T1 - Datenabhängigkeitsanalyse und Programmtransformationen auf CRAY-Rechnern mit dem Fortran-Präprozessor fpp N2 - The FORTRAN preprocessor fpp in the newly introduced Autotasking System of CRAY Research allows automatic vectorization and parallelization on basis of a data dependence analysis. An introduction into data dependence analysis is given, showing how data dependence graphs unveil opportunities for program transformations like vectorization and concurrentization. The report contains a complete description of the preprocessors functionality, its options and directives for increasing the effectiveness of the dependence analyzer and steering the code transformations. Finally, some advice is given for the practical use of fpp on CRAY computers. T3 - ZIB-Report - TR-90-04 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4685 ER - TY - GEN T1 - CRAY-Handbuch. Einführung in die Benutzung der CRAY X-MP unter UNICOS 5.1 N2 - Das CRAY-Handbuch des ZIB beschreibt nach einer grundlegenden bersicht detailliert die Handhabung von UNICOS-Dateien, die Verwendung von UNICOS-Kommandos und schließlich die (für Benutzer allein zugelassene) Ausführung von Batchjobs auf der CRAY. Neben der Erreichbarkeit der CRAY über das TCP/IP-Netz werden die Compiler FORTRAN, PASCAL und C beschrieben und schließlich auf die Optimierung der Rechenzeit ebenso wie auf die Fehlersuche eingegangen. Ein umfangreicher Anhang führt bereitgestellte Programmpakete, weiterführende Literatur, Zahlenbereiche und Zeichendarstellung an der CRAY auf. T3 - ZIB-Report - TR-90-03 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4679 ER - TY - GEN A1 - Gatermann, Karin T1 - Symbolic solution of polynomial equation systems with symmetry. N2 - Systems of polynomial equations often have symmetry. The Buchberger algorithm which may be used for the solution ignores this symmetry. It is restricted to moderate problems unless factorizing polynomials are found leading to several smaller systems. Therefore two methods are presented which use the symmetry to find factorizing polynomials, decompose the ideal and thus decrease the complexitiy of the system a lot. In a first approach projections determine factorizing polynomials as input for the solution process, if the group contains reflections with respect to a hyperplane. Two different ways are described for the symmetric group Sm and the dihedral group Dm. While for Sm subsystems are ignored if they have the same zeros modulo G as another subsystem, for the dihedral group Dm polynomials with more than two factors are generated with the help of the theory of linear representations and restrictions are used as well. These decomposition algorithms are independent of the finally used solution technique. We used the REDUCE package Groebner to solve examples from CAPRASSE, DEMARET and NOONBURG which illustrate the efficiency of our REDUCE program. A short introduction to the theory of linear representations is given. In a second approach problems of another class are transformed such that more factors are found during the computation; these transformations are based on the theory of linear representations. Examples illustrate these approaches. The range of solvable problems is enlarged significantly. T3 - ZIB-Report - SC-90-03 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-311 ER - TY - GEN A1 - Deuflhard, Peter T1 - Global Inexact Newton Methods for Very Large Scale Nonlinear Problems. N2 - Newton methods for nonlinear problems are known to require the solution of a sequence of linear problems of the same type. For very large scale problems, as understood herein, the arising linear systems can only be solved by iterative methods. Then Newtons iteration appears as outer iteration. The question of interest will be to control the accuracy of the inner iteration such that the convergence speed of Newtons method is preserved. The purpose of the paper is to combine the concept of inexact Newton methods with the concept of the affine invariant exact Newton methods - which is important for problems with ill- conditioned Jacobian matrices (such as typical 2-D or 3-D discretized partial differential equations). T3 - ZIB-Report - SC-90-02 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-303 ER - TY - GEN A1 - Maierhöfer, Gerhard A1 - Skorobohatyj, Georg T1 - Implementierung von parallelen Versionen der Gleichungslöser EULEX und EULSIM auf Transputern. N2 - Im vorliegenden Bericht wird die Parallelisierung zweier numerischer Algorithmen zur Lösung gewöhnlicher Differentialgleichungssysteme 1.Ordnung (explizite und semi-implizite Euler- Diskretisierung und $h$-Extrapolation) beschrieben. Implementiert wurden die Algorithmen mit OCCAM2 unter TDS (Transputer Development System) mit bis zu 4 Transputern T800. Meßwerte für die erreichten Beschleunigungen werden anhand mehrer Beispiele von Differentialgleichungs-systemen angegeben. {\bf Schlüsselwörter:} Adaptive, parallele Systeme; OCCAM2; Transputer; numerische Gleichungslöser; Euler-Diskretisierung; $h$-Extrapolation. T3 - ZIB-Report - TR-90-02 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4666 ER - TY - GEN A1 - Gatermann, Karin T1 - Gruppentheoretische Konstruktion von symmetrischen Kubaturformeln. N2 - $G$-invariant cubature formulas for numerical integration over n-dimensional, $G$- invariant integration regions are computed symbolically. The nodes are the common zeros of some $d$-orthogonal polynomials which build an $H$-basis of an ideal. Approaches for these polynomials depending on parameters are made with the help of the theory of linear representations of a group $G$. This theory is also used for the effective computation of necessary conditions which determines the parameters. Another approach uses invariant theory and gröbner bases. T3 - ZIB-Report - TR-90-01 Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4652 ER - TY - GEN A1 - Yserentant, Harry T1 - Two Preconditioners Based on the Multi-Level Splitting of Finite Element Spaces. N2 - 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. T3 - ZIB-Report - SC-89-09 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-274 ER - TY - GEN A1 - Hoppe, Ronald H. W. T1 - Numerical Solution of Multicomponent Alloy Solidification by Multi-Grid Techniques. N2 - 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. T3 - ZIB-Report - SC-89-10 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-285 ER - TY - GEN A1 - Maierhöfer, Gerhard T1 - Ein paralleler adaptiver Algorithmus für die numerische Integration. N2 - 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. T3 - ZIB-Report - SC-89-08 KW - numerischer Algorithmus KW - Romberg Quadratur KW - paralleler adaptiver Algorithmus KW - dynamische Lastverteilung und Prozessorzahl KW - lokaler Speicher KW - Near Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-265 ER - TY - GEN A1 - Maierhöfer, Gerhard A1 - Skorobohatyj, Georg T1 - Implementierung des parallelen TRAPEX auf Transputern. N2 - 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. T3 - ZIB-Report - TR-89-08 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4649 ER - TY - GEN A1 - Grammel, Martin A1 - Maierhöfer, Gerhard A1 - Skorobohatyj, Georg T1 - Trapex in POOL-Implementierung eines numerischen Algorithmus in einer parallelen objektorientierten Sprache. N2 - 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. T3 - ZIB-Report - TR-90-05 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4696 ER - TY - GEN A1 - Bornemann, Folkmar A. T1 - Adaptive multilevel discretization in time and space for parabolic partial differential equations. N2 - 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. T3 - ZIB-Report - TR-89-07 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4638 ER - TY - GEN A1 - Huamo, Wu A1 - Shuli, Yang T1 - MmB-A New Class of Accurate High Resolution Schemes for Conservation Laws in Two Dimensions. N2 - 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. T3 - ZIB-Report - SC-89-06 KW - difference scheme KW - TVD KW - MmB KW - flux limiter Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-248 ER - TY - GEN A1 - Budde, Uwe A1 - Wulkow, Michael T1 - Computation of Molecular Weight Distributions for Free Radical Polymerization Systems. N2 - 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. T3 - ZIB-Report - SC-89-07 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-253 ER - TY - GEN A1 - Huamo, Wu T1 - On the Possible Accuracy of TVD Schemes. N2 - 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. T3 - ZIB-Report - SC-89-03 KW - semi-discrete schemes KW - TVD KW - flux limiter KW - degeneration of accuracy Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-212 ER - TY - GEN A1 - Möller, H. Michael T1 - Multivariate Rational Interpolation: Reconstruction of Rational Functions. N2 - 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. T3 - ZIB-Report - SC-89-04 KW - Multivariante rational interpolation KW - reconstruction KW - symbolic computation Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-227 ER - TY - GEN A1 - Kornhuber, Ralf A1 - Roitzsch, Rainer T1 - On Adaptive Grid Refinement in the Presence of Internal or Boundary Layers. N2 - 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. T3 - ZIB-Report - SC-89-05 KW - adaptive finite elements KW - directed refinement KW - adaptive grid orientation KW - convection diffusion equation KW - internal and boundary layers Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-230 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - Implementation of Portable Standard LISP for the SPARC Processor. N2 - 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. T3 - ZIB-Report - TR-89-06 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4625 ER - TY - GEN A1 - Roitzsch, Rainer T1 - KASKADE Programmer's Manual. N2 - 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. T3 - ZIB-Report - TR-89-05 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4617 ER - TY - GEN A1 - Roitzsch, Rainer T1 - KASKADE User's Manual. N2 - 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. T3 - ZIB-Report - TR-89-04 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4605 ER - TY - GEN T1 - Jahresbericht 1988 T3 - Jahresbericht - 1988 KW - Annual Report Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-9858 SN - 0934-5892 ER - TY - GEN A1 - Zha, Hongyuan T1 - Restricted Singular Value Decomposition of Matrix Triplets. N2 - 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. T3 - ZIB-Report - SC-89-02 KW - Matrix rank KW - singular values KW - generalized singular values KW - product induced singular values KW - restricted singular values KW - matrix decompositions Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-205 ER - TY - GEN A1 - Deuflhard, Peter T1 - Numerik von Anfangswertmethoden für gewöhnliche Differentialgleichungen. N2 - 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. T3 - ZIB-Report - TR-89-02 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4580 ER - TY - GEN A1 - Walter, Artur T1 - Ein Finite-Element-Verfahren zur numerischen Lösung von Erhaltungsgleichungen. N2 - 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. T3 - ZIB-Report - TR-89-03 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4597 ER - TY - GEN A1 - Zha, Hongyuan T1 - A Numerical Algorithm for Computing the Restricted Singular Value Decomposition of Matrix Triplets. N2 - 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. T3 - ZIB-Report - SC-89-01 KW - restricted singular values KW - matrix triplets KW - unitary transformations KW - implicit Kogbetliantz technique Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-194 ER - TY - GEN A1 - Chow, Shui-Nee A1 - Deng, Bo A1 - Fiedler, Bernold T1 - Homoclinic Bifurcation at Resonant Eigen-values. T3 - ZIB-Report - SC-88-10 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-181 ER - TY - GEN T1 - CRAY-HANDBUCH. Einführung in die Benutzung der CRAY X-MP unter UNICOS. (veraltet) T3 - ZIB-Report - TR-89-01 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4574 ER - TY - GEN A1 - Kornhuber, Ralf A1 - Roitzsch, Rainer T1 - Adaptive Finite-Elemet- Methoden für konvektionsdominierte Randwertprobleme bei partiellen Differentialgleichungen. N2 - 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. T3 - ZIB-Report - SC-88-09 Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-170 ER - TY - GEN A1 - Maierhöfer, Gerhard A1 - Skorobohatyj, Georg T1 - Parallel-TRAPEX (Ein paralleler adaptiver Algorithmus zur numerischen Integration; seine Implementierung für SUPRENUM-artige Architekturen mit SUSI). N2 - This paper describes some ways of transforming a sequential adaptive algorithm for numerical evaluation of an integral (Romberg- Quadrature with polynomial Extrapolation method) to a parallel one, such as have been implementad by the authors. We developed an algorithm which preserves the sequential adaptivity and is capable of running on various architectures, dynamically controlling the number of avtive processors depending on the problem. To study the time behaviour, we used the simulator SUSI(SUprenum SImulatur) which is able to simulate SUPRENUM-like architectures. Results are given in part 3. {\bf Keywords:} Romberg quadrature; numerical integration; parallel adaptive algorithm; SUSI; simulation; SUPRENUM; MIMD-Fortran; computer architecture; granularity; load balacing; master-slave-principle. T3 - ZIB-Report - TR-88-05 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4560 ER - TY - GEN A1 - Hoppe, Ronald H. W. A1 - Kornhuber, Ralf T1 - Multi-Grid Solution of Two Coupled Stefan Equations Arising in Induction Heating of Large Steel Slabs. N2 - Induction heating of large steel slabs can be described by a coupled system of nonlinear evolution equations of Stefan type representing the temporal and spatial distribution of the induced magnetic field and the generated temperature within the slab. Discretizing these equations implicitly in time and by finite differences in space, at each time step the solution of a system of difference inclusions is required. For the solution of that system two multi-grid algorithms are given which combined with a nested iteration type continuation strategy to proceed in time result in computationally highly efficient schemes for the numerical simulation of the induction heating process. {\bf Keywords:} induction heating, system of two coupled Stefan equations, multi-grid algorithms. {\bf Subject Classification:} AMS(MOS): 35K60, 35R35, 65H10, 65N05, 65N20, 78A25, 78A55. T3 - ZIB-Report - SC-88-08 KW - induction heating KW - system of two coupled Stefan equations KW - multi-grid algorithms Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-160 ER - TY - GEN A1 - Melenk, Herbert A1 - Möller, H. Michael A1 - Neun, Winfried T1 - Symbolic Solution of Large Stationary Chemical Kinetics Problems. N2 - The paper presents a new application of computer algebra to the treatment of steady states of reaction systems. The method is based on the Buchberger algorithm. This algorithm was modified such that it can exploit the special structure of the equations derived from reaction systems, so even large systems can be handled. In contrast to numerical approximation techniques, the algebraic solution gives a complete and definite overview of the solution space and it is even applicable when parameter values are unknown or undetermined. The algorithm, its adaptation to the problem class and its application to selected examples are presented. T3 - ZIB-Report - SC-88-07 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-157 ER - TY - GEN A1 - Deuflhard, Peter A1 - Wulkow, Michael T1 - Computational Treatment of Polyreaction Kinetics by Orthogonal Polynomials of a Discrete Variable. N2 - The paper presents a new approach to the computational treatment of polyreaction kinetics. This approach is characterized by a Galerkin method based on orthogonal polynomials of a discrete variable, the polymer degree (or chain length). In comparison with the known competing approaches (statistical moment treatment, Galerkin methods for continuous polymer models), the suggested method is shown to avoid the disadvantages and preserve the adventages of either of them. The basic idea of the method is the construction of a discrete inner product associated with a reasonably chosen probability density function. For the so-called Schulz-Flory distribution one thus obtains the discrete Laguerre polynomials, whereas the Poisson distribution leads to the Charlier polynomials. Numerical experiments for selected polyreaction mechanisms illustrate the efficiency of the proposed method. T3 - ZIB-Report - SC-88-06 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-140 ER - TY - GEN A1 - Deuflhard, Peter A1 - Leinen, P. A1 - Yserentant, Harry T1 - Concepts of an Adaptive Hierarchical Finite Element Code. N2 - The paper presents the mathematical concepts underlying the new adaptive finite element code KASKADE, which, in its present form, applies to linear scalar second-order 2-D elliptic problems on general domains. Starting point for the new development is the recent work on hierarchical finite element bases due to Yserentant (1986). It is shown that this approach permits a flexible balance between iterative solver, local error estimator, and local mesh refinement device - which are the main components of an adaptive PDE code. Without use of standard multigrid techniques, the same kind of computational complexity is achieved - independent of any uniformity restrictions on the applied meshes. In addition, the method is extremely simple and all computations are purely local - making the method particularly attractive in view of parallel computing. The algorithmic approach is illustrated by a well-known critical test problem. {\bf Keywords:} finite elements, hierarchical basis, adaptive mesh refinement, preconditioned conjugate gradient methods. T3 - ZIB-Report - SC-88-05 KW - finite elements KW - hierarchical basis KW - adaptive mesh refinement KW - preconditioned conjugate gradient methods Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-131 ER - TY - GEN A1 - Buhtz, Danuta Anna A1 - Langendorf, Jens A1 - Paetsch, Olaf T1 - GRAZIL - 3D. Ein graphisches Anwendungsprogramm zur Darstellung von Kurven- und Funktionsverläufen im räumlichen Koordinatensystem. N2 - GRAZIL - 3D ist ein interaktives Programmpaket zur graphischen Darstellung von dreidimensionalen Kurvenverläufen. Das Aussehen der räumlichen Ausgabe des Bildes wird durch Angabe des Blickwinkels und der Perspektive festgelegt. T3 - ZIB-Report - TR-88-04 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4556 ER - TY - GEN T1 - Jahresbericht 1987 T3 - Jahresbericht - 1987 KW - Annual Report Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-9860 SN - 0933-7903 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - Parallel Polynomial Operations in the Buchberger Algorithm. N2 - The Buchberger algorithm is a basic tool for the solution of systems of polynomial equations in an environment of computer algebra applications. A model for overlapped processing of different steps of the algorithm is presented, which uses the data structure of the polynomials (distributive representation) for synchronization. The model can be applied for multi processors with fast access to shared data. It is tested with Cray X-MP multi processors based on a parallel version of Portable Standard Lisp (PSL 3.4). T3 - ZIB-Report - SC-88-04 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-125 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - REDUCE User s Guide for the CRAY 1 / CRAY X-MP Series Running UNICOS. Version 3.3. N2 - This document describes operating procedures for running REDUCE specific to the CRAY 1 and CRAY X-MP computers running the Operating System UNICOS. 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). T3 - ZIB-Report - TR-88-02 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4539 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - REDUCE Installation Guide for CRAY 1 / X-MP Systems Running UNICOS. Version 3.3. N2 - This guide describes the CRAY/UNICOS REDUCE distribution tape and the procedures for installing, testing and maintaining REDUCE on a CRAY 1 or CRAY X-MP running UNICOS. 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. T3 - ZIB-Report - TR-88-03 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4541 ER - TY - GEN A1 - Buhtz, Rainer A1 - Buhtz, Danuta Anna T1 - TDLG 3.1 - Ein interaktives Programm zur Darstellung dreidimensionaler Modelle auf Rastergraphikgeräten. N2 - TDLG 3.1 dient zur Darstellung von dreidimensionalen Objekten, die sich aus offenen Linienzügen, Dreieck- und Viereckelementen zusammensetzen. Dabei können verschiedene Visualisierungstechniken benutzt werden: Drahtmodell, Schattierung mit und ohne Lichtquelle, Hidden Surface Removal. Durch Verwendung von Konvertierungsprogrammen können auch IGES- und VDAFS- Dateien dargestellt werden. T3 - ZIB-Report - TR-88-01 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4522 ER - TY - GEN A1 - Melenk, Herbert A1 - Möller, H. Michael A1 - Neun, Winfried T1 - On Gröbner Bases Computation on a Supercomputer Using REDUCE. N2 - Gröbner bases are the main tool for solving systems of algebraic equations and some other problems in connection with polynomial ideals using Computer Algebra Systems. The procedure for the computation of Gröbner bases in REDUCE 3.3 has been modified in order to solve more complicated algebraic systems of equations by some general improvements and by some tools based on the specific resources of the CRAY X-MP. We present this modification and illustrate it by examples. T3 - ZIB-Report - SC-88-02 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-107 ER - TY - GEN A1 - Alexander, J. C. A1 - Fiedler, Bernold T1 - Global Decoupling of Coupled Symmetric Oscillators. N2 - We model a symmetric system of coupled oscillators as a graph with symmetry group $\gamma$. Each vertex of the graph represents an "oscillator" or a "cell" of reactants. The magnitude (concentration) of the reactants in the $ i $ th cell is represented by a vector $ x^i $. The edges represent the coupling of the cells. The cells are assumed to evolve by identical reaction-diffusion equation which depends on the sum of the reactants in the nearest neighbors. Thus the dynamics of the system is described by a nonlinear differential system \begin{flushleft} \[ \mbox {(*) \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ } \dot{x}^i = f (x^i,\sum_{j \in N_i} x^j), \mbox { \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ } \] \end{flushleft} where the sum ranges over the set $ N_i $ of neighbors of cell $ i $ . If $ f $ also has a symmetry (e.g., oddness), there are geometric conditions on the graph such that the nonlinear system $ (*) $ decouples globally into a product flow on certain sums of isotropy subspaces. Thus we may detect higher-dimensional tori of solutions of $ (*) $ which are not amenable to other types of analysis. We present a number of examples, such as bipartite graphs, complete graphs, the square, the octahedron, and a 6-dimensional cube. T3 - ZIB-Report - SC-88-03 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-113 ER - TY - GEN A1 - Neun, Winfried A1 - Melenk, Herbert T1 - Implementation of the LISP-Arbitrary Precision Arithmetic for a Vector Processor. N2 - Portable Standard LISP (PSL, Version 3.4) and REDUCE 3 were implemented for CRAY1 and Cray X- MP computers at the Konrad-Zuse-Zentrum Berlin in 1986. As an special aspect of the implementation of PSL, an interface to the vector hardware of CRAY processors was defined. With that interface and mostly driven by the needs of REDUCE applications (e.g. extensive calculations of Gröbner bases), the arbitrary precision integer arithmetic of PSL was rebuild using full power of the vector hardware. A modular arithmetic using vector hardware was also constructed. T3 - ZIB-Report - SC-88-01 Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-93 ER - TY - GEN A1 - Langendorf, Jens A1 - Paetsch, Olaf T1 - GRAZIL (Graphical ZIB Language). N2 - 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. T3 - ZIB-Report - TR-87-07 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4518 ER - TY - GEN A1 - Yserentant, Harry T1 - Preconditioning Indefinite Discretization Matrices. N2 - 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. T3 - ZIB-Report - SC-87-06 KW - preconditioned conjugate gradient methods KW - finite elements Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-81 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - Portable Standard LISP Implementation for CRAY X+MP Computers. Release of PSL 3.4 for COS. N2 - 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. T3 - ZIB-Report - TR-87-02 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4465 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - Portable Common LISP Subset Implementation for CRAY X+MP Computers. N2 - This document describes the installation procedure and maintenance for the Portable Common LISP Subset (PCLS) developed at the University of Utah. T3 - ZIB-Report - TR-87-03 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4479 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - REDUCE Installation Guide for CRAY 1 / X-MP Systems Running COS. Version 3.3. N2 - 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. T3 - ZIB-Report - TR-87-04 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4486 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - REDUCE Users Guide for the CRAY 1 / X-MP Series Running COS. Version 3.3. N2 - 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). T3 - ZIB-Report - TR-87-05 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4498 ER - TY - GEN A1 - Deuflhard, Peter T1 - A Note on Extrapolation Methods for Second Order ODE Systems. N2 - 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. T3 - ZIB-Report - SC-87-05 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-79 ER - TY - GEN A1 - Buhtz, Rainer T1 - CGM-Concepts and their Realizations. N2 - 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. T3 - ZIB-Report - SC-87-04 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-68 ER - TY - GEN A1 - Buhtz, Rainer A1 - Langendorf, Jens A1 - Paetsch, Olaf A1 - Buhtz, Danuta Anna T1 - ZUGRIFF - Eine vereinheitlichte Datenspezifikation für graphische Darstellungen und ihre graphische Aufbereitung. N2 - ZUGRIFF ist eine Dateischnittstelle für Graphikausgabe speziell numerischer Anwenderprogramme. Dieser Report beschreibt den Leistungsumfang der Spezifikation sowie die interaktive graphische Verarbeitung von ZUGRIFF- Dateien. T3 - ZIB-Report - TR-87-06 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4506 ER - TY - GEN A1 - Deuflhard, Peter T1 - Uniqueness Theorems for Stiff ODE Initial Value Problems. N2 - 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. T3 - ZIB-Report - SC-87-03 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-53 ER - TY - GEN T1 - Tätigkeitsbericht 1986 T3 - Jahresbericht - 1986 KW - Annual Report KW - Jahresbericht Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-9871 ER - TY - GEN A1 - Bank, Randolph A1 - Dupont, Todd F. A1 - Yserentant, Harry T1 - The Hierarchical Basis Multigrid Method. N2 - 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. T3 - ZIB-Report - SC-87-02 KW - hierarchical basis KW - multigrid KW - finite elements KW - adaptive mesh refinement KW - preconditioned conjugate gradient methods KW - symmetric Gauss-Seidel Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-44 ER - TY - GEN A1 - Busch, Hubert A1 - Pöhle, Uwe A1 - Stech, Wolfgang T1 - CRAY-Handbuch. - Einführung in die Benutzung der CRAY. N2 - 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. T3 - ZIB-Report - TR-87-01 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4459 ER - TY - GEN A1 - Anderson, J. A1 - Galway, W. A1 - Kessler, R. A1 - Melenk, Herbert A1 - Neun, Winfried T1 - The Implementation and Optimization of Portable Standard LISP for the CRAY. N2 - 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. T3 - ZIB-Report - SC-87-01 Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-31 ER - TY - GEN A1 - Melenk, Herbert A1 - Neun, Winfried T1 - Portable Standard LISP for CRAY X-MP Computers. N2 - 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 the University of Utah, Los Alamos National Laboratories and CRAY Research Inc. at Mendota Heights. During the work on implementing PSL the language LISP was investigated for areas which can be supported by vector hardware. One area was found in the COMMON LISP sequence functions and some typical application areas of LISP programming can be improved by vector processing too. A model for the implementation of vector instructions in LISP was developed. For arithmetic an experimental vectorizing extent of the PSL compiler was constructed. With this means full vector hardware capacity can become available for LISP applications. T3 - ZIB-Report - SC-86-02 Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-28 ER - TY - GEN A1 - Schuster, H. J. T1 - Tätigkeitsbericht-1985. T3 - ZIB-Report - TR-86-01 Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-4443 ER - TY - GEN A1 - Deuflhard, Peter A1 - Nowak, Ulrich T1 - Efficient Numerical Simulation and Identification of Large Chemical Reaction Systems. N2 - New, highly efficient techniques for the numerical simulation and parameter identification of large chemical reaction systems are surveyed. The survey particularly addresses to chemists, which are understood to be potential users of the distributed software packages. These packages are written in the form of interactive dialogue systems - thus enabling chemists to concentrate on the chemistry of their problem. Large scale examples from chemical research environments are included. T3 - ZIB-Report - SC-86-01 Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-14 ER - TY - GEN T1 - Tätigkeitsbericht 1985 T3 - Jahresbericht - 1985 KW - Annual Report KW - Jahresbericht Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-9885 ER -