Send mail to: mgnet@cs.yale.edu for the digests or bakeoff mgnet-requests@cs.yale.edu for comments or help Current editor: Craig Douglas douglas-craig@cs.yale.edu Anonymous ftp repository: ftp.ccs.uky.edu (128.163.209.106) World Wide Web: http://www.mgnet.org or http://casper.cs.yale.edu/mgnet/www/mgnet.html or http://www.cerfacs.fr/~douglas/mgnet.html or http://phase.etl.go.jp/mgnet or http://www.nchc.gov.tw/RESEARCH/Math/mgnet/www/mgnet.html Today's editor: Craig Douglas (douglas-craig@cs.yale.edu) Volume 9, Number 3 (approximately March 31, 1999) Today's topics: Important Dates Virtual Proceedings (Bonn and Copper Mountain) Paper by Beck Ph.D. Dissertation of Feng Wang The future of HPC - DIRECT Questionnaire Algebraic Multigrid (AMG) Pre-print Available from GMD Copper Mountain Conference on Multigrid Methods Schedule ------------------------------------------------------- Date: Wed, 31 Mar 1999 11:23:22 +0500 From: Craig C. DouglasSubject: Important Dates April 19 Title and abstracts (roughly 500 words) are due for the European Multigrid Conference (September 27-30, 1999 at the Universiteit Gent, Belgium). See http://allserv.rug.ac.be/~edick/emg for more details. April 30 Title and abstracts (one page) are due for the International Workshop on Computational Physics (August 2-6, 1999 in Beijing). See http://www.mgnet.org/conferences/iwcp-fftpm.0899.html for more details. ------------------------------------------------------- Date: Wed, 31 Mar 1999 11:24:22 +0500 From: Craig C. Douglas Subject: Virtual Proceedings (Bonn and Copper Mountain) There are two virtual proceedings being worked on at the moment. One is for the Tenth GAMM Workshop on Parallel Multigrid Methods (held in Bonn, Germany during October, 1998). The second is for the Ninth Copper Mountain Conference on Multigrid Methods (held during April, 1999). Anyone who participated in these conferences are welcome to post a paper for the respective virtual proceedings. This does not preclude your publishing your paper elsewhere. If you are interested, contact me by e-mail or see the directions in http://www.mgnet.org/mget-how2sub.html. The Copper pre-proceedings is receiving papers while I am working on this issue. You can see what is there by looking at the web page http://www.mgnet.org/mgnet-ccmm99.html. Papers that come in this week will be installed within 24 hours of receipt. ------------------------------------------------------- Date: Fri, 26 Mar 1999 16:51:04 -0500 From: "Thomas L. Beck" Subject: Paper by Beck Multigrid High Order Mesh Refinement Techniques for Composite Grid Electrostatics Calculations Thomas L. Beck Department of Chemistry University of Cincinnati Cincinnati, OH 45221-0172 Abstract A new method for performing high order mesh refinement multigrid computations in real space is presented. The method allows for accurate linear scaling electrostatics calculations over composite domains with local nested fine patches. The Full Approximation Scheme (FAS) multigrid technique is utilized for a sequence of refinement patches of increasing resolution. Conservation forms are generated on coarse scales by additional defect correction terms which counter the local excess fluxes at the boundaries. Formulas are given for arbitrary order, extending the existing technique of Bai and Brandt. Test calculations are presented for a singular source in three dimensions which illustrate the multigrid convergence properties, numerical accuracy, and correct order of the approach. The paper can be accessed at http://bessie.che.uc.edu/tlb/beck.html under the lind 'research'. The files are ce.ps or ce.pdf Thomas L. Beck | http://bessie.che.uc.edu/tlb/beck.html Department of Chemistry | email:becktl@email.uc.edu University of Cincinnati | phone: 513-556-4886 Cincinnati, OH 45221-0172 | fax: 513-556-9239 Editor's Note: See http://www.mgnet.org/mgnet-papers.html or access it at ------------- http://www.mgnet.org/papers/Beck/ce1.ps.gz ------------------------------------------------------- Date: Mon, 8 Mar 1999 18:38:31 -0800 (PST) From: Subject: Ph.D. Dissertation of Feng Wang Efficient Block Iterative Methods for Convection-Dominated Problems and Multigrid for Long-Thin Elements Feng Wang Ph.D.; May 1998 The Pennsylvania State University Thesis Advisor: Jinchao Xu The purpose of this research is to study efficient iterative methods (especially domain decomposition and multigrid methods) for convection- dominated problems. We present our approaches in two directions. One is a specific type of block iterative method called the ``cross-wind-block (CWB) iterative method''. We divide the computational domain into cross-wind blocks and perform the block iterative algorithm. A specific monotone scheme, the EAFE scheme, has been adopted as the main discretization method in our computation and analysis. Also, to effectively divide the domain into cross-wind blocks and order them in the downwind direction, we apply graph theory to our mesh and the stiffness matrix, and a special depth-first search algorithm, Tarjan's ordering algorithm, is used. The convergence of the CWB method is particularly good for the problems with non-recirculating flows. The solution for the monotone schemes, though with only first order accuracy, may be applied to help construct preconditioners or good initial guesses for higher order schemes, such as streamline diffusion and SUPG schemes. The other approach is to discretize the problem with long-thin elements at its boundary layers. This method is effective in resolving the spurious oscillations usually occur near the boundary layers with the standard Galerkin methods. One application of this long-thin element method is to be used as a preconditioner for spectral methods. Editor's Note: See http://www.mgnet.org/mgnet-papers.html or access it at ------------- http://www.mgnet.org/papers/WangF/PhDthesis.ps.gz ------------------------------------------------------- Date: Thu, 25 Mar 1999 15:56:43 +0000 (GMT) From: Gavin J Pringle Subject: The future of HPC - DIRECT Questionnaire WIN A BOTTLE OF MALT! Which aspect of the SERVICE do you value most? How will your NEEDS change over the next three to five years? What is the ROLE of HPC Centres in Europe? If questions like this concern you, we would like to invite you to complete the following questionnaire: http://www.epcc.ed.ac.uk/direct/directq_index.html One lucky respondent who will be chosen by lot will receive their chosen bottle of malt whisky! EPCC has prepared this questionnaire as a leading partner in the DIRECT project, which is an EU-funded Concerted Action in High Performance Computing and Networking, bringing together fourteen Large-Scale HPC and Data Centres. Help DIRECT reflect your opinions and future needs to the decision-makers by taking a few minutes to fill in the form. The closing date for entry to the prize draw is 30th April 1999. However responses will also be accepted after this date and we encourage you to reply so that your views can be included in this survey. Also, we would be very grateful if you could encourage your colleagues to take part in this survey. We look forward to hearing from you soon. ------------------------------------------------------- Date: Sun, 28 Mar 1999 16:44:27 +0200 From: Klaus Stueben Subject: Algebraic Multigrid (AMG) Pre-print Available from GMD Algebraic Multigrid (AMG): An Introduction with Applications Klaus Stueben GMD/SCAI Schloss Birlinghoven D-53757 St. Augustin Germany e-mail: stueben@gmd.de For copyright reasons, we cannot put the report on the web for downloading. However, pre-prints are available. Just send an e-mail to "stueben@gmd.de". Abstract: Since the early nineties, there has been a strongly increasing demand for more efficient methods to solve large sparse and unstructured linear systems of equations. For practically relevant problem sizes, classical one-level methods had already reached their limits and new hierarchical algorithms had to be developed in order to allow an efficient solution of even larger problems. The purpose of this paper is to give an elementary introduction to the first hierarchical and purely matrix-based approach, algebraic multigrid (AMG). The main idea behind AMG is to extend the classical ideas of geometric multigrid (smoothing and coarse-grid correction) to certain classes of algebraic systems of equations. Besides its robustness and efficiency, the main practical advantage of AMG is that it can directly be applied, for instance, to solve various types of elliptic partial differential equations discretized on unstructured meshes, both in 2D and 3D. Since AMG does not make use of any geometric information, it is a "plug-in" solver which can even be applied to problems without any geometric background, provided that the underlying matrix satisfies certain properties. Although the development of AMG goes back to the early eighties, it still provides one of the most efficient algebraic methods to solve corresponding problems. Compared to the original approach, however, several modifications and extensions have been introduced. In addition to the theoretical basics of AMG, we present a concrete algorithm in some detail and demonstrate its robustness and efficiency by means of a variety of typical applications. Klaus Stueben, GMD/SCAI, Schloss Birlinghoven D-53757 St. Augustin, Germany, stueben@gmd.de Tel: (+49) 2241-14-2749, Fax: (+49) 2241-14-2102 ------------------------------------------------------- Date: Wed, 31 Mar 1999 11:25:22 +0500 From: Craig C. Douglas Subject: Copper Mountain Conference on Multigrid Methods Schedule Ninth Copper Mountain Conference on Multigrid Methods APRIL 11-16, 1999 PROGRAM April 1999 Su M Tu W Th F Sa 1 2 3 4 5 6 7 8 9 8 -----> 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 ------------------------------------------------------------------------ This program is preliminary and subject to modifications. Times given here are only estimates, and are likely to change. We will try to limit most schedule changes to within the given day. Participants and speakers should monitor this page and the bulletin board at the conference. ------------------------------------------------------------------------ Speakers should plan their talks to be at most 20 minutes. Program Chairs will adhere strictly to this schedule. ------------------------------------------------------------------------ We will have a slide projector and an overhead projector for speaker use. We will also provide an In Focus Systems Lite Pro 620 multimedia projector, which plugs into standard video outlets on a Mac or PC to project its image onto the screen. This equipment will also be available for the special evening sessions. ------------------------------------------------------------------------ Wednesday night's cash bar & banquet is in Victoria B in the Pavillon. All other activities will be held in the Village Square conference facilities. ------------------------------------------------------------------------ Sunday, April 11 TUTORIAL Tutorial series on basic methods, algebraic multigrid, and parallel techniques. 9:00am-noon William L. Briggs A Multigrid Tutorial 1:30pm-3:30pmVan Emden Henson An Algebraic Multigrid Tutorial 4:00pm-5:00pmJim E. Jones A Parallel Multigrid Tutorial RECEPTION Cash bar and light buffet. 7:00pm-9:00pmVillage Square conference facilities. Monday, April 12 SESSION 1 Algebraic Methods Chair: Van Emden Henson 8:00am Achi Brandt MG Re-Examined Mark Adams Heuristics for the Automatic Construction of 8:25am Coarse Grids in Multigrid Solvers for Finite Element Problems in Solid Mechanics Michael Bader An Algebraic Multigrid Method with Fixed 8:50am Coarse Grid Selection for Convection Diffusion Equations Tim Chartier Algebraic Multigrid Based on Element 9:15am Interpolation (AMGe): Coarsening and the AMGe Measure Mike DeLong Recent Results with Algebraic Multilevel 9:40am Methods for ASCI Problems 10:05am COFFEE BREAK SESSION 2 Algebraic Methods Chair: Van Emden Henson Joel Dendy Some Aspects of Multigrid for Mixed 10:35am Discretizations Michael Griebel Algebraic Multi-Grid for Coupled Systems 11:00am of PDEs Jim E. Jones Algebraic Multigrid Methods Based on 11:25am Element Agglomeration Domenico Lahaye On the Use of Algebraic Multigrid in an 11:50am Electromagnetic Systems Simulation Package Jens-Dominik Müller Coarsening 3-D Hybrid Meshes for 12:15pm Multigrid Methods SESSION 3 Fluids Chair: Duane Melson Scott R. Fulton Performance of a Self-Adaptive Multigrid 4:30pm Algorithm Klaus Johannsen Robust Multigrid Methods for Convection 4:55pm Diffusion Problems with Closed Characteristics David Kay A Multigrid Preconditioner for the Steady 5:20pm State Navier-Stokes Equations Boris Lastdrager The Sparse-Grid Combination Technique 5:45pm for a Time-Dependent Advection Problem Marius Paraschivoiu Multi-Level Full Potential and Euler 6:10pm Formulation for Transonic Flows CIRCUS Chair: Craig Douglas Everyone is welcome to talk and/or listen. The program will be determined at the start by polling the 7:30pm participants. Contact Craig for suggestions and information, or just show up and be ready to talk, interact, or just listen. Tuesday, April 13 SESSION 4 Algebraic Methods Chair: Van Emden Henson Yousef Saad ARMS : an Algebraic Recursive Multilevel 8:00am Solver for General Sparse Linear Systems Serguei Sokol Applying Multi-Coarse Correction with 8:25am Suboptimal Operators to CFD Problems Ray Tuminaro ML: A Multilevel Framework for Parallel 8:50am Unstructured Grid Computations Jun Zhang A Multilevel Block ILU Preconditioning 9:15am Technique for Solving General Sparse Linear Systems 9:40am COFFEE BREAK SESSION 5 Algebraic Methods Chair: Van Emden Henson John W. Ruge Algebraic Multigrid Applied to Multi-Body 10:10am Elasticity Problems with Interface Constraints Petr Vanek Smoothed Aggregation Multilevel Methods and 10:35am Their Convergence Analysis Jan Mandel Fast Computation of Energy Minimal Coarse 11:00am Basis Functions by Smoothing and Projection Marian Brezina Smoothed Aggregation-Based Black-Box 11:25am Iterative Solver Hervé Guillard A Petrov Galerkin Smoothed Aggregation 11:50am Method 12:15pm Rudolph Lorentz Total Reduction Revisited SESSION 6 Fluids Chair: Irad Yavneh Michael Pernice Hybrid Solvers for the Steady State 4:30pm Incompressible Navier-Stokes Equations William J. Rider A Serendipitous Recovery of Linear 4:55pm Scaling Jonathan Rochez A Multigrid Strategy for Accelerating 5:20pm Steady-State Computations of Waves Propagating with Curvature Dependent Speeds Carol S. Woodward Comparison of Parallel 5:45pm Newton-Krylov-Multigrid Solvers for Variably Saturated Flow Problems Shu-hua Chen The Application of the Multigrid Method in a 6:10pm Nonhydrostatic Atmospheric Model ALGEBRAIC METHODS Moderator: Van Emden Henson BULL SESSION 7:30pm Open discussion on algebraic methods. Everyone is welcome to talk and/or listen. Wednesday, April 14 SESSION 7 Parallel Algebraic Methods Chair: Jim E. Jones Ulrike Meier Yang Coarse-Grid Selection for 8:00am Parallel Algebraic Multigrid 8:25am Arnold Krechel Parallel Algebraic Multigrid Marc Alexander Schweitzer Three Parallelization 8:50am Strategies for AMG Dimitri J. Mavriplis A Highly Scalable 9:15am Unstructured Agglomeration Multigrid Algorithm for Viscous Turbulent Flows 9:40am COFFEE BREAK SESSION 8 Parallel Techniques Chair: Jim E. Jones Colin J. Aro Implicit Mechanical Modeling in 10:10am ALE3D Craig C. Douglas Accelerating ADI Methods on 10:35am Parallel Processors including Multigrid with ADI as the Smoother 11:00am Paul O. Frederickson Recent Results on PUMG Ignacio M. Llorente Smoothing Properties for 11:25am Plane Smoothers for Multiblock Grids William F. Mitchell Approaches to Parallel 11:50am Multigrid with the Full Domain Partition SESSION 9 PDE Reformulations Chair: Kirk Jordan Travis Austin Multigrid Ideas in FOSLS Neutron 4:30pm Transport Theory Markus Berndt Multigrid for FOSLS on the 4:55pm Discontinuous Coefficient Problem with Singular Basis Functions Zhiqiang Cai Least Squares for the Perturbed 5:20pm Stokes Equations and the Reissner-Mindlin Plate Andrea Codd Steady-State Elasticity-Fluid 5:45pm Coupled Systems Johannes Korsawe FAS Multilevel Methods for 6:10pm Nonlinear Least-Squares Finite Element Computations Irad Yavneh Towards Automatic Differential 6:35pm Preconditioning and Variable Transformations for PDE Systems BANQUET Cash bar and banquet. 7:30pm Victoria B room in the Pavillion. Thursday, April 15 SESSION 10 Parallel Techniques Chair: Jim E. Jones David Moulton MPI-Based Black Box Multigrid for 8:00am Workstation Clusters I. D. Parsons Scalable Multigrid Methods Using Fortran 8:25am 90 and MPI Markus Kowarschik How Much Can Be Gained by Cache 8:50am Aware Programming of Multigrid Methods Jonathan Hu Cache Based Multigrid on Unstructured 9:15am Grids 9:40am COFFEE BREAK SESSION 11 Parallel Techniques Chair: Jim E. Jones Dana Knoll A Parallel, Two-Level, Preconditioner for 10:10am Unstructured Grid Elliptic Problems Stefan Vandewalle A Multigrid Method for Partial 10:35am Differential Equations with Time-Delay Gerhard Zumbusch Parallelization of an Adaptive 11:00am Multilevel Code Using Keys and a Space-Filling Curve Guo Qingping Virtual Boundary Condition Forecast 11:25am Algorithm in Multigrid Domain Decomposition Parallel Computing Wing Lok Wan Parallel Sparse Approximate Inverse 11:50am Smoothers SESSION 12 Inverse Problems Chair: Eldad Haber Eldad Haber Inversion of 3D DC Resistivity Using 4:30pm Approximate Krylov-Gauss-Newton Method Uri M. Ascher A Multilevel Approach to Distributed 4:55pm Parameter Estimation Yaoguo Li Rapid Construction of an Equivalent Source 5:20pm Using Wavelet Transforms and Incomplete Conjugate Gradients Gregory Newman Computational Techniques for 5:45pm Accelerating Solutions of 3D Geophysical Inverse Problems SESSION 13 Special Methods Chair: Eldad Haber Zhangxin Chen Convergence Analysis of Multigrid 6:10pm Methods for the Wilson Nonconforming Finite Element Linda Stals Performance of Multilevel Methods on 6:35pm Equations with Large Jumps in Coefficients Friday, April 16 SESSION 14 Parallel and Algebraic Chair: Jim E. Jones Methods Michael Kuhn A Unifying Software Concept for 8:00am Several Parallelization Techniques Gundolf Haase Parallel AMG for Non-overlapping 8:25am Domain Decomposition Stefan Reitzinger Algebraic Multigrid Methods 8:50am Based on Element Stiffness Matrices Ping Wang Parallel Computation of 3D, 9:15am Time-dependent, Thermal Convective Flows 9:40am COFFEE BREAK SESSION 15 Decomposition Methods Chair: Panayot Vassilevski Susanne C. Brenner Lower Bounds for 10:10am Nonoverlapping Domain Decomposition Methods Serge Goossens Two-level Algorithms for 10:35am Overlapping Composite Mesh Difference Methods Thomas Huckle Multigrid Preconditioning and 11:00am Toeplitz Matrices David E. Keyes Newton-Krylov Methods with Multilevel Preconditioning: 11:25am Algorithm-Architecture Trade-offs in the Number of Levels Maria Sosonkina Distributed Multilevel Schur 11:50am Complement Preconditioning of General Sparse Linear Systems Wienands Fourier Analysis of GMRES(m) 12:15pm Preconditioned by Multigrid 12:40pm End of conference Editor's Note: See http://amath-www.colorado.edu/appm/faculty/copper/1999/program.html ------------- for last minute changes to the program. ------------------------------ End of MGNet Digest **************************