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
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World Wide Web:  http://na.cs.yale.edu/mgnet/www/mgnet.html or
                 http://www.cerfacs.fr/~douglas/mgnet.html

Today's editor:  Craig Douglas (douglas-craig@cs.yale.edu)

Volume 6, Number 7 (approximately July 31, 1996)

Today's topics:

     Strobl Virtual Proceedings
     Triangle Mesh Generator Available
     Data structures for adaptive multilevel-FEM methods
     Updated Codes: UG version 3.3 and PLTMG version 7.2
     1995 Copper Mountain Proceedings
     Some of the new entries in the bibliography

*****************************************************************************
***** August is traditionally a slow month.  Please send contributions. *****
*****************************************************************************

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

Date: Wed, 3 Jul 96 08:52:01 +0200
From ghaase@mephisto Wed Jul  3 03:18:36 1996
Subject: Strobl Virtual Proceedings

                  Virtual Proceedings 
                        of the
              9th International GAMM-Workshop 
                          on
                Parallel Multigrid Methods

at

    http://www.numa.uni-linz.ac.at/Workshops/proceedings.html  

are available.

    Editor's Note: in mgnet/Conferences/ParMGM96 and the MGNet web page for
    -------------  this conference.  Here is a list of what is there so far:


Clemens Brand and Johannes Kraus:  Preconditioning by Approximative Schur
Complements on Hierarchical Grids

Dietrich Braess:  Towards Algebraic Muligrid for Elliptic Problems of Second
Order.

Michael Czajkowski :  Application of Multigrid to an Initial Control Problem.

Wolfgang Dahmen :  Stable Multiscale Bases and Adaptive Techniques for
Elliptic Problems.

Craig Douglas :  Caching in with Multigrid Algorithms:  Problems in Two
Dimensions.

Jurgen Fuhrmann :  A Modular Algebraic Multilevel Method.

Csaba Gaspar:  Flow modelling using quadtrees and multigrid technique.

Klaus Gartner :  Improved Separators by Multigrid Methods.

Wolfgang Hackbusch :  Downwind Gauss-Seidel Smoothing for Convection Dominated
Problems.

Volker John :  Parallel Solution Schemes for the Navier-Stokes Equation using
the Crouzeix/Raviart-Element.

Michael Jung :  Parallelization of multi-grid methods based on domain
decomposition ideas.

Michael Jung and Michael Thess :  Parallel Multilevel Solvers for 3D Problems.

Holger Matthes :  Parallel preconditioners for plate and shell problems.

Maya Neytcheva ,Owe Axelsson and Krassimir Georgiev :  Algebraic Multilevel
Iteration Method on massively parallel computer architectures.

Ulrich Rude :  Performance Aspects of Iterative Methods on Superscalar
Computers.

Barry Smith :  Abstract Parallel Multigrid Software in PETSc 2.0.

Ivan Sofronov :  Jump-Keeping and Upwind Transfer in MultiGrid for Upwind
Schemes.

Rob Stevenson :  A Robust Hierarchical Basis Preconditioner on General Meshes.

Karsten Urban :  A multiscale method for separation processes in chemnical
engineering.

Yuri Vassilevski, Yuri Iliash and Yuri Kuznetsov :  Efficient Parallel Solving
the Potential Flow Problem on Nonmatching Grids.

Frank Wagner :  Time-paralle Multigrid Methods for Two-Phase Stefan Problems.
 
-------------------------------------------------------

From: Jonathan Shewchuk 
Date: Sun, 21 Jul 96 21:24:43 EDT
Subject: Triangle Mesh Generator Available

Triangle Version 1.3
A Two-Dimensional Quality Mesh Generator and Delaunay Triangulator.

Triangle generates 2D Delaunay triangulations, Voronoi diagrams, convex
hulls, constrained Delaunay triangulations, and quality conforming
Delaunay triangulations.  The latter can be generated with no small
angles, and are thus suitable for finite element analysis.  Triangle
includes an implementation of Ruppert's Delaunay refinement algorithm
for 2D meshing.  Users can specify constraints on minimum angle and
maximum triangle area, and can refine previously generated meshes based
on a posteriori error estimates.  Support is included for holes,
concavities, internal boundaries, and intersecting segments.

The Delaunay triangulations and constrained Delaunay triangulations
produced are exact, but very little speed is sacrificed to gain this
robustness.  Hence, Triangle is useful not only for finite element
practitioners, but also for computational geometers who seek a
comparison to validate the robustness of their codes against.

Triangle is accompanied by a simple X program called "Show Me", whose
purpose is to display point sets, planar straight line graphs,
triangulations, partitions, and Voronoi diagrams.  It also creates
PostScript output.

Triangle is about 13,000 lines of portable C code, and Show Me about 3,400.
Each is a single, easy-to-compile file.

New features in Version 1.3:  Faster file reading.  Interface for calling
Triangle from another program.  Attributes that allow you to determine which
(segment-bounded) region a triangle falls in.  Triangle neighbor lists.
Objects can be numbered from zero.  Ability to suppress insertion of new
points on the boundary, thus preserving compatibility with adjacent meshes.
Handles duplicate input points correctly.

Full online documentation for Triangle is available on the Web at

    http://www.cs.cmu.edu/~quake/triangle.html

Jonathan Shewchuk
School of Computer Science
Carnegie Mellon University
jrs@cs.cmu.edu

    Editor's Note: in mgnet/Codes/triangle.
    -------------

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

From: Juergen Fuhrmann 
Date: Mon, 24 Jun 96 11:50:11 +0200
Subject: Data structures for adaptive multilevel-FEM methods

The 1st Workshop 

  "Data structures for adaptive multilevel-FEM methods"

took place at the Weierstrass Institute for Applied Analysis and Stochastics
(WIAS) in Berlin, on May 29.- 31.1996.  It was initiated by R.Kornhuber (Univ.
Stuttgart) and organized by J.Fuhrmann, H.Langmach (WIAS) and by R.Roitzsch,
B.Erdmann, R.Beck (ZIB).

The workshop has been divided into two parts:  a "classical" talks section,
where the participants had the possibility to present their approaches to the
topic, and a discussion section, where three working groups discussed the
following topics:

* Efficiency of the implementation of adaptive algorithms
* Programming in Scientific Computing (motivation and aims)
* Software interfaces for finite element applications

Detailed information you can find on the WWW page
  http://www.wias-berlin.de/~amfem.
Because of some access problems, there is a mirror of this site at
  http://www.zib-berlin.de/~amfem.

The topics of these discussions, and the topic of the workshop as a whole, are
seldomly covered by events in scientific life, even though Scientific
Computing would not exist without serious efforts in software development.
The participants felt that it had been very useful to meet at this workshop
and that it would be worth to try to continue the work of this meeting.

For this purpose, a  moderated mailing list  
        amfem-l@zib-berlin.de
has been installed.  To subscribe the mailing list, send an e-mail to
       majordomo@zib-berlin.de
with the body
       subscribe amfem-l
The contributions to this mailing list  are collected on 
       http://elib.zib-berlin.de/amfem-l.

Everyone interested in the topic of the workshop or who is concerned with
programming and data structure issues for Scientific Computing, is invited to
participate.  Especially, submissions to the sparse matrix benchmark effort
(see the summary of the discussion of the efficiency working group at the
www-page) are welcome.

In the hope of a fruitful discussion

Juergen Fuhrmann
Rainer Roitzsch

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

Date: Tue, 30 Jul 1996 12:12:12 GMT
From: Craig Douglas 
Subject: Updated Codes: UG version 3.3 and PLTMG version 7.2

Two software packages on MGNet have been updated recently.  The first is UG
version 3.3, from Gabriel Wittum's institute at Stuttgart (thank you, Peter
Bastian for this).  The other is PLTMG version 7.2, from Randy Bank at the
University of California at San Diego.

    Editor's Note: in mgnet/Codes/ug/ug3.3 and
    -------------     mgnet/Codes/pltmg.

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

Date: Mon, 29 Jul 1996 19:51:06 GMT
From: Duane Melson 
Subject: 1995 Copper Mountain Proceedings

Craig,
They still have not been mailed out yet.  I hate to give an estimate again
because none of the rest of my estimates have worked out.  If you would,
please mention in the next digest that attendees of the conference should make
sure that I have their current address so that I can mail out their copies as
soon as they are available.
Duane

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

Date: Mon, 29 Jul 1996 18:12:10 -0500
From: Craig Douglas 
Subject: Some of the new entries in the bibliography

Randy Bank submitted his list of publications, some of which are included
below.

Here are some recent new entries.  As usual, please send additions and
corrections.  The most recently posted bibliography is dated July 29, 1996.

                             REFERENCES

  [1] B.  Achchab  and  J.  F.  Maitre,  Estimate  of  the  constant
          in two strenghtened C.B.S. inequalities for the F.E.M. sys-
          tem of the 2D elasticity. application to multilevel methods
          and a posteriori error estimators, Numer. Lin. Alg. Appl., 3
          (1996), pp. 147-159.
  [2] O.  Axelsson,  An  algebraic  framework  for  hierarchical  basis
          function multilevel methods or the search for `optimal' pre-
          conditioners, in Iterative Methods for Large Linear Systems,
          Academic Press, New York, 1990, pp. 7-40.
  [3] ______, Iterative Solution Mehtods, Cambridge University Press,
          Cambridge, 1994.
  [4] ______,  Stbilization  of  algebraic  multilevel  iteration;  additive
          methods,  in  AMLI'96:  Proceedings  of  the  Conference  on
          Algebraic Multilevel Iteration Methods with Applications,
          vol. 1, Nijmegan, The Netherlands, 1996, University of Ni-
          jmegan, pp. 49-62.
  [5] O.  Axelsson  and  M.  Neytcheva,  A  survey  of  multilevel
          preconditioned iterative methods,  Numer. Lin. Alg. Appl.,
          1 (1994), pp. 213-236.
  [6] ______, Scalable algorithms for the solution of Navier's equations
          of elasticity, J. Comp. Appl. Math., 63 (1995), pp. 149-178.
  [7] O.  Axelsson  and  B.  Polman,  AMLI'96:  Proceedings  of
          the  Conference  on  Algebraic  Multilevel  Iteration  Methods
          with Applications, University of Nijmegan, Nijmegan, The
          Netherlands, 1996.
  [8] O. Axelsson and P. S. Vassilevski, A survey of multilevel
          preconditioned iterative methods, BIT, 29 (1989), pp. 769-
          793.
  [9] ______, Asymptotic work estimates for AMLI methods, Appl. Nu-
          mer. Math., 7 (1991), pp. 437-451.
[10]  Z.-Z. Bai, A class of hybrid algebraic multilevel preconditioning
          methods, Appl. Numer. Math., 19 (1996), pp. 389-399.
[11]  Z.-Z.  Bai  and  O.  Axelsson,  A  unified  framework  for  the
          construction of various algebraic multilevel preconditioning
          methods,  in  AMLI'96:  Proceedings  of  the  Conference  on
          Algebraic Multilevel Iteration Methods with Applications,
          vol. 1, Nijmegan, The Netherlands, 1996, University of Ni-
          jmegan, pp. 63-76.
[12]  R. E. Bank, Marching Algorithms for Elliptic Boundary Value
          Problems, PhD thesis, Division of Engineering and Applied
          Physics, Harvard University, Cambridge, MA, 1975.
[13]  ______, A multi-level iterative method for nonlinear elliptic equa-
          tions, in Elliptic Problem Solvers, M. H. Schultz, ed., Aca-
          demic Press, New York, 1981, pp. 1-16.
[14]  ______, Efficient implementation of local mesh refinement algo-
          rithms, in Adaptive Computational Methods for Partial Dif-
          ferential Equations, I. Babu~ska, J. Chandra, and J. E. Fla-
          herty, eds., SIAM, Philadelphia, 1984, pp. 74-81.
[15]  ______, Analysis of a local a posteriori error estimator for elliptic
          equations, in Accuracy Estimates and Adaptivity in Finite
          Element Computations, J. Wiley & Sons, New York, 1986,
          pp. 119-128.
[16]  ______, Computational Aspects of VLSI Design with an Empha-
          sis on Semiconductor Device Simulation, vol. 25 of Lecture
          Notes in Applied Math., American Mathematical Society,
          Providence, 1990.
[17]  ______, Hierarchical preconditioners for elliptic partial differen-
          tial equations, in Large Scale Matrix Problems and the Nu-
          merical Solution of Partial Differential Equations, Oxford
          University Press, Oxford, UK, 1994, pp. 121-155.
[18]  ______, Hierarchical bases and the finite element method, vol. 5
          of Acta Numerica, Cambridge University Press, Cambridge,
          1996, pp. 1-43.
[19]  R. E. Bank, R. Bulirsch, H. Gajewski, and K. Merten,
          Mathematical Modelling and Simulation of Electrical Cir-
          cuits and Semiconductor Devices, vol. 117 of Int. Series Nu-
          mer. Math., Birkh"auser, Basel, 1994.
[20]  R. E. Bank, R. Bulirsch, and K. Merten, Mathematical
          Modelling and Simulation of Electrical Circuits and Semi-
          conductor  Devices,  vol.  93  of  Int.  Series  Numer.  Math.,
          Birkh"auser, Basel, 1990.
[21]  R. E. Bank and H. D. Mittelmann, Stepsize selection in
          continuation  procedures  and  damped  Newton's  method,  J.
          Comp. and Appl. Math., 26 (1989), pp. 67-78.
[22]  R.  E.  Bank  and  R.  F.  Santos,  Analysis of some moving
          space-time finite element methods, SIAM J. Numer. Anal.,
          30 (1993), pp. 1-18.
[23]  R.  E.  Bank,  A.  H.  Sherman,  and  A.  Weiser,  On  the
          regularity of local mesh refinement,  in Proceedings of the
          IMACS Tenth World Conference, New Brunswick, NJ, 1982,
          IMACS.
[24]  R. E. Bank, B. D. Welfert, and H. Yserentant, A class
          of iterative methods for solving mixed finite element equa-
          tions, Numer. Math., 56 (1990), pp. 645-666.
[25]  R. E. Bank and J. Xu, A hierarchical basis multigrid method
          for unstructured grids, in Fast Solvers for Flow Problems.
          Proceedings of the Tenth GAMM-Seminar Kiel, vol. 49 of
          Notes on Numerical Mathematics,  Vieweg-Verlag,  Braun-
          schweig, 1995, pp. 1-13.
[26]  ______, An algorithm for coarsening unstructured meshes, Numer.
          Math., 73 (1996), pp. 1-36.
[27]  B. Bialecki and M. Dryja, Preconditioned conjugate gradi-
          ent multilevel methods for orthogonal spline collocation dis-
          cretization of the Dirichlet problem for Poisson's equation,
          in AMLI'96:  Proceedings of the Conference on Algebraic
          Multilevel Iteration Methods with Applications, vol. 1, Ni-
          jmegan,  The  Netherlands,  1996,  University  of  Nijmegan,
          pp. 77-89.
[28]  E. F. F. Botta, A. van der Ploeg, and F. W. Wubs, A
          fast linear-system solver for large unstructured problems on a
          shared-memory parallel computer, in AMLI'96: Proceedings
          of the Conference on Algebraic Multilevel Iteration Methods
          with Applications, vol. 1, Nijmegan, The Netherlands, 1996,
          University of Nijmegan, pp. 105-116.
[29]  V. V. Denissenko, The multilevel iteration method for 2-D
          problems, that simulate transfer processes with assymmetric
          coefficients matrix, in AMLI'96: Proceedings of the Confer-
          ence on Algebraic Multilevel Iteration Methods with Appli-
          cations, vol. 1, Nijmegan, The Netherlands, 1996, University
          of Nijmegan, pp. 117-125.
[30]  R. E. Ewing and S. Maliassov, Preconditioning techniques
          for  mixed  and  nonconforming  finite  element  methods,  in
          AMLI'96: Proceedings of the Conference on Algebraic Mul-
          tilevel  Iteration  Methods  with  Applications,  vol.  1,  Ni-
          jmegan,  The  Netherlands,  1996,  University  of  Nijmegan,
          pp. 7-22.
[31]  R.  E.  Ewing,  S.  Maliassov,  Yu.  A.  Kuznetsov,  and
          R. Lazarov, Substructure preconditioning for porous flow
          problems,  in  Finite  Element  Modeling  of  Environmental
          Problems, G. Garey, ed., New York, 1995, John Wiley &
          Sons, pp. 303-332.
[32]  G. Fiorentino and S. Serra, A o algebra based multiiterative
          solver for (block) Toeplitz systems, in AMLI'96: Proceedings
          of the Conference on Algebraic Multilevel Iteration Methods
          with Applications, vol. 1, Nijmegan, The Netherlands, 1996,
          University of Nijmegan, pp. 129-140.
[33]  J. Fuhrman, Outlines of a modular algebraic multilevel method,
          in AMLI'96:  Proceedings of the Conference on Algebraic
          Multilevel Iteration Methods with Applications, vol. 1, Ni-
          jmegan,  The  Netherlands,  1996,  University  of  Nijmegan,
          pp. 141-152.
[34]  K. Gustavson, Trigonometric interpretation of iterative meth-
          ods, in AMLI'96:  Proceedings of the Conference on Alge-
          braic Multilevel Iteration Methods with Applications, vol. 1,
          Nijmegan, The Netherlands, 1996, University of Nijmegan,
          pp. 23-29.
[35]  B.  Heise  and  M.  Jung,  Robust  parallel  Newton-multilevel
          methods,  in  AMLI'96:  Proceedings  of  the  Conference  on
          Algebraic Multilevel Iteration Methods with Applications,
          vol. 1, Nijmegan, The Netherlands, 1996, University of Ni-
          jmegan, pp. 153-168.
[36]  R. H. W. Hoppe and B. Wolmuth, Efficient numerical solu-
          tion of mixed finite element discretizations by adaptive mul-
          tilvel methods, Appl. Math., 40 (1995), pp. 227-248.
[37]  Yu. A. Kuznetsov, Efficient iterative solvers for elliptic finite
          element problems on nonmatching grids,  Russ. J. Numer.
          Anal. Math. Modeling, 10 (1995), pp. 187-211.
[38]  Yu. A. Kuznetsov and S. Maliassov, Substructuring pre-
          conditioners  for  nonconforming  finite  element  approxima-
          tions of second-order elliptic problems with anisotropy, Russ.
          J. Numer. Anal. Math. Modeling, 10 (1995), pp. 511-533.
[39]  Yu. A. Kuznetsov and M. H. Wheeler, Optimal order sub-
          structuring preconditioners for mixed finite element methods
          on nonmatching grids, E. W. J. Numer. Math., 3 (1995),
          pp. 127-143.
[40]  S. Maliassov, Optimal Order Preconditioners for Mixed and
          Nonconforming Finite Element Approximations of Elliptic
          Problems with Anisotropy, PhD thesis, Texas A&M, College
          Station, TX, 1996.
[41]  S. Margenov, Semi-coarsening AMLI algorithms for elastic-
          ity problems, in AMLI'96: Proceedings of the Conference on
          Algebraic Multilevel Iteration Methods with Applications,
          vol. 2, Nijmegan, The Netherlands, 1996, University of Ni-
          jmegan, pp. 179-193.
[42]  G. Muratova and L. Krukier, Multigrid method for the iter-
          ative solution of strongly nonselfadjoint problems with dissi-
          pative matrix, in AMLI'96: Proceedings of the Conference on
          Algebraic Multilevel Iteration Methods with Applications,
          vol. 2, Nijmegan, The Netherlands, 1996, University of Ni-
          jmegan, pp. 169-178.
[43]  M. Neytcheva, O. Axelsson, and K. Georgiev, An appli-
          cation of the AMLI method for solving convection-diffusion
          problems with potentialvelocity field, in AMLI'96:  Proceed-
          ings  of  the  Conference  on  Algebraic  Multilevel  Iteration
          Methods with Applications, vol. 2, Nijmegan, The Nether-
          lands, 1996, University of Nijmegan, pp. 197-210.
[44]  Y. Notay, An efficient algebraic multilevel preconditioner ro-
          bust with respect to anisotropies, in AMLI'96:  Proceedings
          of the Conference on Algebraic Multilevel Iteration Methods
          with Applications, vol. 2, Nijmegan, The Netherlands, 1996,
          University of Nijmegan, pp. 211-228.
[45]  S. Oliveira, A preconditioned multigrid subspace algorithm for
          computing eigenvalues and eigenvectors, in AMLI'96:  Pro-
          ceedings of the Conference on Algebraic Multilevel Iteration
          Methods with Applications, vol. 2, Nijmegan, The Nether-
          lands, 1996, University of Nijmegan, pp. 229-232.
[46]  T. Rossi, Ficticious Domain Methods with Separable Precon-
          ditioners, PhD thesis, University of Jyv"askyla, Jyv"askyla,
          Finland, 1995.
[47]  Y.  Shapira,  Black  box  multigrid  solver  for  definite  and  in-
          definte problems, in AMLI'96:  Proceedings of the Confer-
          ence on Algebraic Multilevel Iteration Methods with Appli-
          cations, vol. 2, Nijmegan, The Netherlands, 1996, University
          of Nijmegan, pp. 235-250.
[48]  O.  Shishkina,  Optimality  of  the  pseudodiagonal  hierarchical
          preconditioner, in AMLI'96: Proceedings of the Conference
          on  Algebraic  Multilevel  Iteration  Methods  with  Applica-
          tions, vol. 2, Nijmegan, The Netherlands, 1996, University
          of Nijmegan, pp. 251-258.
[49]  B.  F.  Smith,  P.  E.  Bjorstad,  and  W.  D.  Gropp,  Do-
          main  Decomposition:  Parallel  Multilevel  Methods  for  El-
          liptic Partial Differential Equations, Cambridge University
          Press, New York, 1996.
[50]  K.  Urban,  Using  divergence  free  wavelets  for  the  numerical
          solution of the Stokes problem, in AMLI'96: Proceedings of
          the Conference on Algebraic Multilevel Iteration Methods
          with Applications, vol. 2, Nijmegan, The Netherlands, 1996,
          University of Nijmegan, pp. 261-277.
[51]  P.  S.  Vassilevski,  Multilevel  preconditioning  matrices  and
          multigrid  V-cycle  methods,  in  Proceedings,  4th  GAMM-
          Seminar Kiel, Jan. 1988, W. Hackbusch, ed., vol. 23 of Notes
          on Numerical Fluid Mechanics, Braunschweig, 1989, Vieweg,
          pp. 200-208.
[52]  ______,   Hybrid  V-cycle  algebraic  multilevel  preconditioners,
          Math. Comp., 58 (1992), pp. 489-512.

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

End of MGNet Digest
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