Send mail to: mgnet@cs.yale.edu for the digests mgnet-requests@cs.yale.edu for comments or help Anonymous ftp repository: ftp.ccs.uky.edu (128.163.209.106) World Wide Web: http://www.mgnet.org or http://www.cerfacs.fr/~douglas/mgnet.html or http://phase.etl.go.jp/mgnet or http://www.ccs.uky.edu/mgnet Today's editor: Craig Douglas (douglas-craig@cs.yale.edu) Volume 8, Number 9 (approximately September 30, 1998) Today's topics: www.mgnet.org Machine DD11 Proceedings EMG 99 More Efficient Parallelizable MUDPACK Paper on Parallel MGM 2 Preprints by Bittencourt, Douglas, and Feijoo ------------------------------------------------------- Date: Thu, 01 Oct 1998 14:42:12 -0200 From: Craig Douglas Subject: www.mgnet.org Machine The computer that www.mgnet.org aliases to has been upgraded to a much, much faster computer. Hopefully, this will relieve some of the problems that have been reported. Currently, anonymous ftp is not on. I may turn it back on when I return from the GAMM Workshop on Parallel Multigrid Methods that will be held in the coming week. Please access this machine using your favorite web browser for the time being. ------------------------------------------------------- Date: Thu, 10 Sep 1998 15:01:54 +0100 From: Subject: DD11 Proceedings The deadline for paper submission is October 31st 1998. Please see more details on http://dd11.gre.ac.uk/proceedings.html or simply go to the final announcement and click on the section 'Proceedings'. A conference report can also be found in European Mathematical Society Newsletter, Issue 29, September 1998. DD11 Local Organising Committee ------------------------------------------------------- Date: Fri, 18 Sep 1998 09:48:24 +0000 From: erik.dick@rug.ac.be Subject: EMG 99 PRELIMINARY ANNOUNCEMENT Sixth European Multigrid Conference September 27-30, 1999 Universiteit GENT, BELGIUM The department of Flow, Heat and Combustion Mechanics of the University of Ghent is organising the European Multigrid Conference `99. Earlier conferences were held in Cologne in 1981 and 1985, in Bonn in 1990, in Amsterdam in 1993 and in Stuttgart in 1996. Conference themes will concern all aspects of multigrid methods: theory and applications. The conference will be held in the conference centre of the University of Ghent, located in the historic heart of the city. The conference fee is expected to be around 300 Euro (350 US$), including admission to all sessions, lunches, coffee breaks, reception, conference dinner, excursion and the book of abstracts. Following the tradition of the conference, invited lectures and selected presentations will appear as full papers in the conference proceedings, to be published by Springer or Birkhauser. Academia Press Ghent will publish the remaining presentations. The proceedings by Springer or Birkhauser will be offered at reduced price. The proceedings by Academia Press Ghent are included in the conference fee. Contact address: Prof. E. Dick, Universiteit GENT, Sint-Pietersnieuwstraat 41, B-9000 GENT, Belgium, Fax: +32-9-264 35 86, Email: Erik.Dick@rug.ac.be. For inclusion on the mailing list, please fill in the form at location http://allserv.rug.ac.be/~edick/emg. ------------------------------------------------------- Date: Mon, 21 Sep 1998 08:38:05 -0600 (MDT) From: johnad@niwot.scd.ucar.edu (John Adams) Subject: More Efficient Parallelizable MUDPACK A new version 4.0 of the multigrid software package MUDPACK is now available on the world wide web. The web site includes a detailed description and instructions for downloading the source code after signing software licensing agreement with the University Corporation for Atmospheric Research. Since it inception, portions of MUDPACK have been distributed to hundreds of users from foreign institutions and within the U.S. The new version was created to simplify and modernize the package. MUDPACK 4.0 has been passed through fortran verification software and compiled and executed on a variety of platforms with both fortran 77 and fortran 90. The resulting streamlining has yielded code which is more efficient and more amenable to parallelization than the earlier versions. MUDPACK 4.0 replaces and is incompatible with earlier versions. The software includes a suite of portable fortran programs which automatically discretize and use multigrid techniques to generate second- and fourth-order approximations to elliptic Partial Differential Equations (PDEs) on rectangular regions. The elliptic PDEs can be real or complex in two- and three-dimensions with any combination of mixed derivate, specified, or periodic boundary conditions. Multigrid V or W cycles which use point, line(s), or planar relaxation and fully weighted residual restriction are available for algorithm tuning to obtain optimal multigrid performance. MUDPACK was written to avoid repeated "re-invention of the wheel" in human code development time which can be at least as important as saving machine cycles. ------------------------------------------------------- Date: Sun, 27 Sep 1998 07:28:35 +0800 From: Guo Qingping Subject: Paper on Parallel MGM Fabled Boundary Condition Forecast Algorithm in Domain Decomposition Multigrid Parallel Computing Guo Qingping Wuhan Transportation University, Wuhan 430063, P. R. China qpguo@public.wh.hb.cn guo@dcs.qmw.ac.uk Yakup Paker Queen Mary and Westfield College, University of London, E1 4NS, U.K. paker@dcs.qmw.ac.uk Zhang Shesheng Wuhan Transportation University, Wuhan 430063, P. R. China Dennis Parkinson Queen Mary and Westfield College, University of London, E1 4NS, U.K. Wei Jialin Wuhan Transportation University, Wuhan 430063, P. R. China Abstract We propose a fabled boundary condition forecast algorithm for multigrid parallel computing, and derive a forecast function formula in this paper. Numerical results of one and two dimension boundary condition problems obtained with the algorithm in a PVM network computing environment show that the algorithm has high parallel efficiency. Keywords: Multi-Grid, Domain Decomposition, Boundary Condition Forecast Editor's Note: This can be found through www.mgnet.org/mgnet-papers.html ------------- or mgnet/papers/Qingping-et-al/fablebc.{doc,pdf}. ------------------------------------------------------- Date: Wed, 30 Sep 1998 11:23:56 -0400 (EDT) From: Marco Bittencourt Subject: 2 Preprints by Bittencourt, Douglas, and Feijoo Adaptive Non-Nested Multigrid Methods Marco L. Bittencourt Center for Computational Sciences University of Kentucky 325 McVey Hall, Lexington, KY, 40506-0045, USA e-mail: mlb@ccs.uky.edu Craig C. Douglas Department of Mathematics University of Kentucky 715 Patterson Office Tower, Lexington, KY, 40506-0027, USA e-mail: douglas@ccs.uky.edu Raul A. Feijoo Laboratorio Nacional de Computacao Cientifica (LNCC/CNPq) Av. Getulio Vargas 333, CEP 25651-070, Petropolis/RJ, Brazil e-mail: feij@alpha.lncc.br Abstract This paper presents some linear adaptive non-nested multigrid methods which are applied to linear elastic problems discretized with triangular and tetrahedral finite elements using unstructured and Delaunay mesh generators. The Zienkiewicz-Zhu error estimator and a h-refinement procedure are used to obtain the non-nested meshes used by the multigrid methods. We solve problems with a specified percentage error in the energy norm using the optimal performance of multigrid methods. * * * * * Non-Nested Multigrid Methods for Linear Problems Marco L. Bittencourt Craig C. Douglas Raul A. Feijoo Abstract This paper presents an application of non-nested and unstructured multigrid methods to linear elastic problems. A variational formulation for transfer operators and some multigrid strategies, including adaptive algorithms, are presented. Expressions for the performance evaluation of multigrid strategies and its comparison with direct and preconditioned conjugate gradient algorithms are also presented. A C++ implementation of the multigrid algorithms and its quadtree and octree data structures are discussed. Some two and three dimensional elasticity examples are analyzed. Editor's Note: Both can be found through www.mgnet.org/mgnet-papers.html ------------- or mgnet/papers/Bittencourt-Douglas-Feijoo/paper{3,4}.ps.gz. ------------------------------ End of MGNet Digest **************************