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.ccs.uky.edu/mgnet or
                 http://na.cs.yale.edu/mgnet/www/mgnet.html or
                 http://www.cerfacs.fr/~douglas/mgnet.html or
                 http://phase.etl.go.jp/mgnet

Today's editor:  Craig Douglas (douglas@ccs.uky.edu)

Volume 7, Number 9 (approximately September 30, 1997)

Today's topics:

     MGNet anonymous ftp site moves
     Correction from Last Issue
     Two Papers from Jun Zhang
     Preprints on transpose free parallel ADI acceleration
     Updated Paper (Shapira)
     GAMM-Seminar Kiel on Concepts of Numerical Software
     C3 AD'98
     [DD11] - Preliminary Notice
     4th Numerical Methods Conference in Sofia, Bulgaria

-------------------------------------------------------

Date: Tue, 30 Sep 1997 22:12:34 -0400
From: Craig Douglas 
Subject: MGNet anonymous ftp site moves

The anonymous ftp site for MGNet has moved from Yale to the University of
Kentucky, effective a few days ago.  If you are mirroring MGNet through
anonymous ftp, please change the address to

    ftp.ccs.uky.edu    (ip address 128.163.209.106)

The web pages for how to submit/retrieve files have changed to reflect this
change (actually, the web pages have all changed for a variety of reasons).

In particular, the incoming directory is not useful at Yale anymore.

There is still an up to date copy at Yale, but it is not accessible until the
old casper.cs.yale.edu is actually turned off.

-------------------------------------------------------

Date: Wed, 3 Sep 1997 09:39:27 -0500 (CDT)
From: JUN ZHANG 
Subject: Correction from Last Issue

The preprint that was announced in MGNet should have had a title that reads  
 
     BILUM: Block Versions of Multi-Eliminantion and Multi-Level
     ILU Preconditioner for General Sparse Linear Systems

which is currently missing.

    Editor's Note: my fault, sorry... see http://www.cs.umn.edu/~jzhang
    -------------  for the preprint.

-------------------------------------------------------

Date: Tue, 23 Sep 1997 22:51:21 -0500 (CDT)
From: JUN ZHANG 
Subject: Two Papers from Jun Zhang

      On Convergence and Performance of Iterative Methods
               with Fourth-Order Compact Schemes
 (to appear in Numerical Methods for Partial Differential Equations)

                         Jun Zhang

     Department of Mathematics, The George Washington University, 
                     Washington, DC 20052

     (    Department of Computer Science and Engineering
          University of Minnesota, Minneapolis, MN 55455  )

                      December 13, 1996

                         ABSTRACT

We study the convergence and performance of iterative methods with the
fourth-order compact discretization schemes for the one and two dimensional
convection-diffusion equations.  For the one dimensional problem, we
investigate the symmetrizability of the coefficient matrix and derive
analytical formula for the spectral radius of the point Jacobi iteration
matrix.  For the two dimensional problem, we conduct Fourier analysis to
determine the error reduction factors of several basic iterative methods and
comment on their potential use as the smoothers for the multi-level methods.
Finally, we perform numerical experiments to verify our Fourier analysis
results.

    Editor's Note: in mgnet/papers/Zhang/fourier.ps.gz
    -------------

                             * * * * * * * * * *

    Residual Scaling Techniques in Multigrid, II: Practical Applications
         (to appear in Applied Mathematics and Computation)

                             Jun Zhang 

       Department of Mathematics, The George Washinton University
                      Washington, DC 20052

       (   Department of Computer Science and Engineering
           University of Minnesota, Minneapolis, MN 55455  )
   
                          July 1, 1996

                            ABSTRACT 

This paper focuses on practical applications of the multigrid residual scaling
techniques and is the continuation of a companion paper:  Residual scaling
techniques in multigrid, I:  equivalence proof.  We discuss the computational
issues of some residual scaling techniques which have been proved
mathematically equivalent.  A heuristic residual analysis technique, based on
the geometry of the grid points and the relaxation pattern, is introduced to
estimate the optimal residual scaling factor for a high-order multigrid
method.  We compare the performance of a typical pre-optimization
(pre-acceleration) technique with a typical post-optimization
(post-acceleration) technique and show that the pre-optimization is preferable
in both convergence and efficiency.  Our numerical results support theoretical
conclusions made in the companion paper and demonstrate full advantage of the
pre-optimization technique over the post-optimization technique.

    Editor's Note: in mgnet/papers/Zhang/scaling2.ps.gz
    -------------

Jun Zhang, Ph.D.                  * e-mail: jzhang@cs.umn.edu
Department of Computer Science    * Tel:  (612) 626-0071
University of Minnesota           * Fax:  (612) 625-0572
Minneapolis, MN 55455, USA        * http://www.cs.umn.edu/~jzhang

-------------------------------------------------------

Date: Tue, 30 Sep 1997 22:12:34 -0400
From: Craig Douglas 
Subject: Preprints on transpose free parallel ADI acceleration

         Parameter Choices for ADI-like Methods on Parallel Computers

                                 S. Malhotra

                       Scientific Computing Associates
                              One Century Tower
                              265 Church Street
                        New Haven, CT 06510-7010, USA

                                C. C. Douglas

                          Department of Mathematics
                            University of Kentucky
                          715 Patterson Office Tower
                        Lexington, KY 40506-0027, USA

                                M. H. Schultz

               Department of Computer Science, Yale University
                               P.O. Box 20-8285
                        New Haven, CT 06520-8285, USA

                                   Abstract

Alternating direction iterative (ADI) methods do not usually work well on
parallel computers due to having to do parallel rather than serial tridiagonal
solves in all but one dimension.  An ADI-like iteration is developed and
analyzed which does not require parallel tridiagonal solves in any direction,
has at least as good of a convergence rate as ADI, and has almost no
communication when a small number of iterations are used.  Acceleration
parameters are investigated in order to reduce the number of of iterations to
a small number.  Numerical experiments on a network of workstations and a
parallel computer are also included.

Key words:  alternating direction implicit methods, ADI, partial differential
equations, iterative methods, parallel computing

    Editor's Note: in mgnet/papers/Malhotra-Douglas-Schultz/adiparam.ps.gz
    -------------

                             * * * * * * * * * *

      ``Transpose Free'' Alternating Direction Smoothers for Serial and
                          Parallel Multigrid Methods

                                C. C. Douglas

                          Department of Mathematics
                            University of Kentucky
                          715 Patterson Office Tower
                        Lexington, KY 40506-0027, USA

                                 S. Malhotra

                       Scientific Computing Associates
                              One Century Tower
                              265 Church Street
                        New Haven, CT 06510-7010, USA

                                M. H. Schultz

               Department of Computer Science, Yale University
                               P.O. Box 20-8285
                        New Haven, CT 06520-8285, USA

                                   Abstract

Alternating Direction Implicit (ADI) methods are very good smoothers for
multigrid.  Like multigrid itself, ADI propagates information very quickly
across a grid.  On parallel processors, ADI is very inefficient due to the
tridiagonal solves in each of the spatial directions.  In one direction, the
data typically resides in one processor.  In the other directions, the data
spans processor memories on distributed memory machines.

In this paper, a ``transpose free'' variant of ADI is considered which
eliminates the drawback of ADI on parallel processors.  In addition, it is
quite useful on serial computers.  We provide convergence rates for a model
problem and numerical results for variable coefficient elliptic problems in
two and three dimensions.

Key words:  multigrid, alternating direction implicit methods, iterative
methods, parallel computing, elliptic partial differential equations.

    Editor's Note: in mgnet/papers/Douglas-Malhotra-Schultz/adimg3d.ps.gz
    -------------

-------------------------------------------------------

Date: Wed, 24 Sep 1997 15:42:37 -0600 (MDT)
From: Yair Shapira 
Subject: Updated Paper

A Multi-Level Method for Sparse Linear Systems

    Editor's Note: in mgnet/papers/Shapira/amg.ps.gz
    -------------

-------------------------------------------------------

Date: Fri, 29 Aug 1997 15:11:31 +0200 (MET DST)
From: Jens Burmeister 
Subject: GAMM-Seminar Kiel on Concepts of Numerical Software

I would like to announce the 

  14th GAMM-Seminar Kiel on 'Concepts of Numerical Software'
  January 23rd to 25th, 1998,
  University of Kiel, Germany.
 
Chairmanship:  
  
  Wolfgang Hackbusch (Kiel), Gabriel Wittum (Stuttgart) 

Seminar topics are

   - Concepts of software development in general for 
       . partial differential equations, 
       . integral equations,
       . grid generation,
       . graphical postprocessing, etc. 
   - Design and Modelling of numerical software, 
   - Implementation aspects ; i.e. 
       . parallelization and vectorization,
       . objectoriented realizations, etc. 

For more information please visit our homepage

   http://www.numerik.uni-kiel.de/gamm/

With best regards
Jens Burmeister

-------------------------------------------------------

Date: Thu, 25 Sep 97 19:02:44 -0300
From: Mauricio Vieira Kritz 
Subject: C3 AD'98

C3 AD'98
Colloquia on High Performance Scientific Computation
Date: 17th to 22nd August 1998
Place: LNCC, Petropolis, Rio de Janeiro, Brazil
Web: http://www.lncc.br/c3ad/98

-------------------------------------------------------

Date: Wed, 10 Sep 1997 16:27:26 +0100
From: 
Subject: [DD11] - Preliminary Notice

Dear Colleague,

This email is to draw your attention that the 11th International Conference
on Domain Decomposition will be held at the University of Greenwich, UK
during July 20 - 24, 1998.  Please mark your diary.

You may wish to send your full surface mailing address in order to receive
further paper/flyers etc.

Email address: dd11@gre.ac.uk
A web page has also been set up, please check http://dd11.gre.ac.uk/
You will find call for papers on that web page very soon.

Local Organising Committee
University of Greenwich + Others

-------------------------------------------------------

Date: Wed, 24 Sep 1997 17:37:23 +0300
Subject: 4th Numerical Methods Conference in Sofia, Bulgaria
From: Panayot Vassilevski 

                  FIRST ANNOUNCEMENT and CALL for PAPERS

                     4th International Conference on
                Numerical Methods and Applications: NMA'98
                  August 19 - 23, 1998, Sofia, BULGARIA.

  ----------------------------------------------------------------------
  The Institute of Mathematics and Informatics, Bulgarian Academy of Sciences,
  in cooperation with
     Central Laboratory for Parallel Processing, Bulgarian Academy of Sciences,
     Faculty of Mathematics and Informatics, University of Sofia, and
     Society for Industrial and Applied Mathematics (SIAM)
  is organizing the 4th International Conference on Numerical Methods
  and Applications.
  ----------------------------------------------------------------------
  Honorary Chairman: Blagovest Sendov (Bulgaria)
  ----------------------------------------------------------------------
  International Program Committee:
  Chairman: Michail Kaschiev (Bulgaria)
  H.Niederreiter (Austria), I.Dimov, S.Radev (Bulgaria), Z.Zlatev
  (Denmark), P.G.Ciarlet, B.Philippe (France), M.Griebel, W.Hackbusch,
  U.Jaekel, S.Rjasanow, M.Schaefer (Germany), O.Axelsson, P.Hemker,
  H.A.van der Vorst (The Netherlands), Z.Kamont, J.Popenda (Poland),
  B.N.Chetverushkin, R.P.Fedorenko, S.K.Godunov, S.P.Kurdyumov,
  Yu.P.Popov, I.V.Puzynin, A.A.Samarskii, P.N.Vabishchevich (Russia),
  V.Thomee (Sweden), L.Xanthis (UK), J.H.Bramble, R.E.Ewing, L.Perkins,
  M.F.Wheeler (USA), R.Lazarov (USA/Bulgaria), Yu.A.Kuznetsov
  (USA/Russia)
  ----------------------------------------------------------------------
  Conference Topics:
    (1) Finite difference methods;
    (2) Finite element methods;
    (3) Finite volume methods;
    (4) Boundary element methods;
    (5) Monte Carlo methods;
    (6) Numerical linear algebra;
    (7) Parallel computing;
    (8) Numerical methods for non-linear problems;
    (9) Numerical methods for multiscale problems;
   (10) Multigrid and domain decomposition;
   (11) Computational fluid dynamics;
   (12) Mathematical modeling in structural mechanics;
   (13) Environmental modelling;
   (14) Engineering applications;
   (15) Minisymposia.
  ----------------------------------------------------------------------
  List of key and invited lecturers, who already accepted invitation of
  the Org.Committee:
  O.Axelsson (The Netherlands), J.H.Bramble (USA), B.N.Chetverushkin
  (Russia), R.E.Ewing (USA), R.P.Fedorenko (Russia), S.K.Godunov
  (Russia), M.Griebel (Germany), P.Hemker (The Netherlands), U.Jaekel
  (Germany), Z.Kamont (Poland), S.P.Kurdyumov (Russia), Yu.A.Kuznetsov
  (USA/Russia), R.Lazarov (USA/Bulgaria), H.Niederreiter (Austria),
  L.Perkins (USA), B.Philippe (France), Yu.P.Popov (Russia), I.V.Puzynin
  (Russia), S.Rjasanow (Germany), A.A.Samarskii (Russia), M.Schaefer
  (Germany), V.Thomee (Sweden), P.N.Vabishchevich (Russia), H.A.van der
  Vorst (The Netherlands), M.F.Wheeler (USA), L.Xanthis (UK), Z.Zlatev
  (Denmark)
  ----------------------------------------------------------------------
  Organizing Committee:
  Chairmen: Oleg Iliev and Panayot Vassilevski (Bulgaria)
  P.Binev, A.Karaivanova, M.Koleva, N.Kol'kovska, I.Lirkov, S.Margenov,
  S.Petrova, D.Vassileva, P.Yalamov (Bulgaria), M.Nikolova
  (The Netherlands), I.Bazhlekov, M.Neytcheva (The Netherlands/Bulgaria),
  A.Q.M.Khaliq, M.Paprzycki (USA), P.Entchev, L.Zikatanov (USA/Bulgaria)
  ======================================================================
  Conference Presentations:
  The conference will include key and invited lectures, as well as
  contributed talks. Duration of the presentations will be tentatively
  45, 35, and 25 min. A conference rule is that each participant will
  personally present no more then one talk. Presentation of posters will
  be considered, as well. The conference language will be English.
  ----------------------------------------------------------------------
  CALL FOR ORGANIZING MINISYMPOSIA:
  To contribute a Minisymposium please provide the conference organizers
  with:
       a) minisymposium title, name and address of the organizer
       b) minisymposium abstract
       c) titles and authors of a minimum of 4 presentations
       d) abstracts of presentations (optional).

       Minisymposia proposals due: November 30, 1997
       Minisymposia acceptance decision: December 31, 1997
  ----------------------------------------------------------------------
  CALL FOR PAPERS:
  People wishing to present a paper in a field related to the conference
  topics are invited to submit two hard copies of the paper, and its
  electronic version in LaTeX format by e-mail. The deadline is February
  15, 1998. Papers should not exceed 12 pages for key and invited
  lectures, and 8 pages for contributed talks. Notification of
  acceptance and mandatory format of the final manuscript will be sent
  around May 1, 1998.
  ----------------------------------------------------------------------
  Conference Proceedings:
  Proceedings (in a book form), of only refereed and presented at the
  conference papers, will be published.
  ----------------------------------------------------------------------
  Abstracts:
  Abstracts (of a maximum 1 page) are required from all participants
  wishing to present a talk at the conference. Abstracts have to be send
  as ASCII files via e-mail. The deadline is February 15, 1998.
  ----------------------------------------------------------------------
  Accommodation and Registration Fees:
  The living expenses (single room accommodation and full board) is
  currently estimated at the range of $250 for 5 days. Lower price
  accommodation is also planned to be available.

  The conference fee will cover publishing of the conference
  proceedings, conference booklet, excursion, conference dinner,
  reception, transportation from and to airport. Participants in the
  conference will be offered to buy the volume of the conference
  proceedings at a special price (to be specified later, subject to
  discussion with the Publisher).

  Conference fee is
                       before June 15, 1998    after June 15, 1998
   Non-students          180 US dollars           230 US dollars
   Students              100 US dollars           120 US dollars
   Accompanying person    80 US dollars            80 US dollars
  ----------------------------------------------------------------------
  Deadlines:
   Submission of minisymposia proposals:         November 30, 1997
   Minisymposia acceptance decision:             December 31, 1997
   Submission of abstracts, papers and early
   registration forms:                           February 15, 1998
   Notification of acceptance of full
   papers/presentations:                         May      01, 1998
   Registration and submission of accommodation
   forms:                                        June     15, 1998
  ----------------------------------------------------------------------
  Registration Form:
  An early on-line registration is available on either of our WWW-pages:
  http://banmatpc.math.acad.bg/~nma98/reg_form.html
  http://orca.st.usm.edu/marcin/mp/cfp/reg_form.html

  Another possibility to registrate is to fill-in and to send us via
  e-mail (or ordinary mail) the listed below registration form.
  ----------------------------------------------------------------------
  For further information respond to the e-mail address:
  nma98@math.acad.bg,
  or check either of our WWW-pages:
  http://banmatpc.math.acad.bg/~nma98/
  http://orca.st.usm.edu/marcin/mp/cfp/sofia.html

  The mailing address of the Organizing Committee can also be used:

  NMA'98, c/o Dr. Oleg Iliev
  Institute of Mathematics and Informatics
  Bulgarian Academy of Sciences
  Acad. G. Bonchev Str., Bl.8, 1113 Sofia, BULGARIA

  Fax-No. (++359 2) 971 36 49

  E-mail communication is preferred.
  ----------------------------------------------------------------------
  The next announcement will be distributed in December 1997.
  ----------------------------------------------------------------------

  ======================================================================

                        Early Registration Form

  For nonstandard characters, please, use LaTeX notations.

  ======================================================================

   Title           .........
   Name            .........
   First Name      .........
   Institution     .........
   Street/P.O.Box  .........
   Zip Code        .........
   City, State     .........
   Country         .........

   Fax             .........
   Telephone       .........
   E-mail          .........

   I wish to present:
        a talk      yes/no
        a poster    yes/no

   I am interested in having my paper
   published in the conference proceedings            yes/no

   I declare that the paper is original and has not
   been submitted for publication elsewhere           yes/no

   Title of the contributed talk .........

   My talk is related to the topic (please, specify a
   number (1-15) from listed above conference topics)
        first choice   ...
        second choice  ...

   I am a student   yes/no

   I shall be accompanied by  ...  (non-scientific) persons

  ======================================================================

------------------------------

End of MGNet Digest
**************************