### Today's Editor:

- Jack Dongarra
- University of Tennessee / Oak Ridge National Labs
- dongarra@cs.utk.edu
- Stan Green
- University of Tennessee
- sgreen@cs.utk.edu
- (Cleve's away on travel.)

- GAMM-SIAM Conference on "Inverse Problems in Diffusion Processes"
- ICRM parallelization
- Position at the Department of Computer Science at Purdue University
- LAA policy on publication of research
- FTP at UTIA Available
- Release 1.1 of CUTE is now available
- SIMAX 15-1 Table of Contents
- New book: Numerical Methods for Advection-Diffusion Problems, etc, Vol 45
- Announcing 1994 SIAM Annual Meeting
- Algorithm analysis and efficiency
- Upstate Numerical Analysis Day -- Cornell University

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

From: Heinz W. Engl <engl@indmath.uni-linz.ac.at>

Date: Mon, 08 Nov 1993 12:07:55 EST

**Subject: GAMM-SIAM Conference on "Inverse Problems in Diffusion Processes"**

GAMM-SIAM Conference on

"Inverse Problems in Diffusion Processes"

St.Wolfgang, Austria

June 27 - July 1, 1994

First Announcement

This conference is the first one in a series of conferences on

different application fields of inverse problems. The organizing

committee for this series consists of David Colton (Newark, DE, USA),

Heinz W. Engl (Linz, Austria), Alfred Louis (Saarbr|cken, Germany),

and William Rundell (College Station, TX, USA). In addition, there

is an advisory committee consisting of M.Bertero, G.Chavent,

M.Cheney, R.Ewing, A.Friedman, R.Kre_, K.Kunisch, P.Sabatier, and

W.Symes.

The first conference is organized locally by Heinz W. Engl and

focusses on inverse problems as they appear in the mathematical

formulation of diffusion processes, both transient (parabolic pde's)

and steady-state (elliptic pde's). This includes parameter

identification problems and problems involving side conditions that

render them ill-posed. Besides questions of uniqueness and

stability, numerical algorithms and applications in science and

technology are of special interest.

The following invited speakers have so far confirmed their presence

at least tentatively: A.Bakushinskii, J.Beck, G.Crosta, L.Elden,

A.Friedman, Hong-Ming Yin, V.Isakov, K.Kunisch, A.Lorenzi, D.Ross,

T.Seidman, G.Vainikko, S.Vessella, and K.Zeman.

In addition to invited talks, there will also be the possibility of

some contributed talks of 30 minutes (including discussion) fitting

into the scope of the meeting. Participants who wish to give a talk

should indicate below and include an abstract. Since we want to

avoid parallel sessions, we also encourage participation at this

conference just by being there and taking part in the discussions!

The meeting will be held in a conference center on Lake St.Wolfgang

in one of the most picturesque parts of the Austrian Alps. Because

of space limitations, the meeting will be open to up to 120

participants. Therefore, we suggest early registration!

The most convenient airport (and train station) is Salzburg, Austria.

Salzburg has good flight connections to major gateway airports in

central Europe and good train connections to Munich and Vienna.

Since June/July is high tourist season, early flight bookings are

advised. However, please do not make a firm booking before you hear

from us! Detailed travel information from Salzburg onwards will be

sent in a second announcement.

Participants should arrive at the conference center on June 26 and

leave on July 2. The total price for accomodation and full board for

this period is currently 4000 Schilling (minor changes possible;

currently, 7.15 Schilling = 1 DM, 11 Schilling = 1 US$).

Accomodation for accompanying persons is very limited in the

conference center, but double rooms in hotels can be booked if we

know early enough (at different prices depending on the category).

There will be a conference fee of up to 1400 Schilling. This also

includes an excursion on Wednesday afternoon (price for accompanying

persons: 250 Schilling). If our funding applications are

successful, this conference fee might be substantially smaller. The

exact amount will not be known until a few weeks before the meeting.

In addition to this possible reduction of the conference fee,

financial support for participants other than invited speakers is not

available.

If you want to receive the registration material, please contact me

by e-mail at

engl@indmath.uni-linz.ac.at

or by Fax at

+43-732-246810, attn.Prof.Engl

or by mail at

Prof.Dr.Heinz W.Engl

Kepler-Universitdt

A-4040 Linz, Austria.

Those who have already replied to an earlier preliminary announcement

need not reply again, they will receive the registration material

soon.

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

From: Lorie Liebrock <lorie@cs.rice.edu>

Date: Mon, 8 Nov 93 09:07:35 CST

**Subject: ICRM parallelization**

I am working on algorithms for automating the distribution of ICRM (Irregularly

Coupled Regular Mesh) problems across parallel processors in Fortran D.

Other names for ICRM problems are composite grid and multi-block.

ICRM problems typically involve the simulation of material dynamics

in or around complex topology bodies. For example, one of the areas I am

interested in is aerodynamics simulations where each mesh represents

some component (e.g., body, wing, pylon, etc.) and the couplings represent

the seams or connections between the parts. In the aerodynamics case

the flow of air over the components may be the phenomenon of interest.

I am interested in any and all applications with such connected components.

My work is also intended to support ICRM problems for which the grids

have been generated automatically.

I am looking for a few test problems that I can use in validation of my

algorithms. I am also looking for researchers with ICRM problems that

would be willing to discuss their applications and programs so that we can

continue improving support for these problems in Fortran D. Please

send me any comments and let me know if you or someone you know has

applications in this class.

Lorie M. Liebrock

lorie@cs.rice.edu

Ph.D. Candidate

Computer Science

Rice University

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

From: John R. Rice <jrr@cs.purdue.edu>

Date: Mon, 08 Nov 93 16:56:09 EST

**Subject: Position at the Department of Computer Science at Purdue University**

Purdue University is establishing an interdisciplinary

graduate program in Computational Science and Engineering.

It is expected to involve eventually perhaps 20 departments,

75-100 faculty and over 100 graduate students. The Depart-

ment of Computer Sciences seeks a highly qualified person

dedicated both to research and teaching at the Assistant

Professor level to support this program. Areas of speciali-

zation considered appropriate include scientific computing,

high performance computing, geometry systems, mathemtical

software, applications of computing to science and engineer-

ing, and related areas. The department currently has a

number of substantial research projects in this area.

A new Computational Science and Engineering laboratory

will be established with graphical and multi-media facili-

ties for teaching and research. These will supplement the

existing extensive computing facilities of the department:

several large Sun file/computer servers, a 64 processor

nCube 2, nearly 200 workstations from Sun, Silicon Graphics,

Hewlett-Packard and a complete video production facility.

Purdue also has Intel, IBM, and MasPar parallel/vector com-

puters and is a member of the Concurrent Supercomputing Con-

sortium which operates a 512 processor Intel Paragon.

Applications are solicited for appointments to begin in

late August 1994. Send curriculum vita and the names of

three references by March 1, 1994 to:

Chair, CS&E Search Committee

Department of Computer Sciences

Purdue University

W. Lafayette, IN 47907

Purdue University is in a college town of about 25,000,

part of the Lafayette metropolitan area of about 125,000

people. The schools are excellent, commuting is easy, the

cost of living is reasonable, and there is a full range of

athletic and cultural events at the University. Salaries

are competitive and Purdue has one of the best packages of

fringe benefits of any university.

Purdue University is an Equal Opportunity/Affirmative Action Employer

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

From: Hans Schneider <hans@math.wisc.edu>

Date: Mon, 8 Nov 1993 17:38:41 -0600 (CST)

**Subject: LAA policy on publication of research**

LAA policy on publication of research.

This announcement discusses a certain aspect of the publication policy

of LAA (which is probably similar to that of most mathematical

research journals). The central point is that LAA publishes *original

research* (plus some expository articles, book reviews etc. , which

will not be further discussed in this announcment). The obvious

consequence is that research previously published elsewhere cannot be

republished in LAA.

Our policy allows two kinds of previous appearance of this research.

First, a preprint (hardcopy or electronic) is not considered to be a

publication and therefore a paper that has been made available as a

preprint can (of course) be considered for publication in LAA. Second,

publication (in LAA or elsewhere) of an (extended) abstract or

synopsis of the research does not preclude publication of the full

paper in LAA.

This sounds simple, but occasionally misunderstandings have arisen

because there are grey areas which (in the nature of grey areas)

cannot be delineated precisely. But below we shall attempt to give

some indications on how to distinguish a publication from a preprint

and a paper from an abstract or synopsis.

1. What distinguishes a publication from preprint?

An article (or series thereof) may be considered to have been

published if any of the following hold:

a. it bears the imprint of a recognized publisher,

b. it is for sale and can be ordered through a bookstore,

c. it is being reviewed by Math Reviews.

In-house proceeding of conferences (available to participants only)

are not normally considered to be publications.

2. What distinguishes a paper from an abstract or synopsis?

This is hard. Obviously, the length of an extended abstract is at most

a few pages. Normally, the absence of proofs of essentially all

significant new results indicates the article is an abstract.

But it should be understood that, when there is doubt, the

editor-in-chief reserves the right to decide the above questions in

each individual case.

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

From: John J. Hench <hench@utia.cas.cz>

Date: Tue, 9 Nov 93 13:12:20 +0100 (MET)

**Subject: FTP at UTIA Available**

As of the first of November 1993, technical reports from the Institute of

Information Theory and Automation of the Academy of Sciences of the Czech

Republic are available via FTP. These reports are available in full as

compressed postscript files, and should be printable on 300dpi postscript

printers. Furthermore, a separate document is available that contains the

abstracts of all of these technical reports.

To access these reports, type:

ftp visla.utia.cas.cz

The computer will respond:

Connected to visla.utia.cas.cz.

220 visla FTP server (Version 16.2 Fri May 24 17:03:27 GMT 1991) ready.

Name (visla.utia.cas.cz:yourname):

Type after the prompt:

anonymous

The computer will respond:

331 Guest login ok, send ident as password.

Password:

Use your e-mail address as your password, eg.:

yourname@youruniversity.edu

The technical report series is contained in the directory /pub/reports .

In this section there is a file called README . This contains all of the

necessary information to access the technical reports.

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

From: Philippe Toint <pht@math.fundp.ac.be>

Date: Tue, 09 Nov 93 18:03:04 +0100

**Subject: Release 1.1 of CUTE is now available**

CUTE (Constrained and Unconstrained Testing Environment) is a set of Fortran

subroutines, system tools and test problems in the area of nonlinear

optimization and nonlinear equations. Its purpose is to

- provide a way to explore an extensive collection of problems (over 600

different test problems today),

- provide means of comparing existing packages,

- provide a way to use a large test problem collection with new packages,

- provide a mechanism to manage and update the system efficiently, and

- do all the above on a variety of popular platforms.

NEW * The new release provides interfaces to new optimization packages. In addition

* to the existing interfaces for MINOS, OSL, UNCMIN, VF13, VE09 and VE14,

* CUTE now contains interfaces for

* - NPSOL (Gill, Murray, Saunders and Wright SQP code),

* - TENMIN (Schnabel and Chow tensor code) and

* - VA15 (Nocedal's limited memory code).

* The MINOS interface has also been improved to allow selective sizing in

* order to accommodate machines with different amounts of memory.

NEW * The new release also supports two new computer platforms. Besides

* CRAY/Unicos, DEC/ULTRIX, IBM/AIX and SUN/SunOS, CUTE is now available

* with fully automated installation procedures for DEC/OSF and DEC/VMS.

NEW * Handling of external libraries, like BLAS and the Harwell Subroutine Library,

* has been improved.

* Known bugs have also been corrected.

CUTE has been written by I. Bongartz, A.R. Conn (both at IBM, Watson Research

Center), Nick Gould (CERFACS, France) and Ph. Toint (FUNDP, Belgium). A LaTeX

manuscript detailing the package may be obtained by email from any of the

authors. It is also included in the distribution.

CUTE is written is standard ANSI Fortran 77. Single and double precision

versions are available. Machine dependencies are carefully isolated and

easily adaptable.

The package may be obtained in one of two ways. Firstly, the reader can

obtain CUTE electronically (and free of charge) via an anonymous ftp call to

the account at the Rutherford Appleton Laboratory camelot.cc.rl.ac.uk

(Internet i.d. 130.246.8.61, in the directory pub/cute), or at Facultes

Universitaires Notre-Dame de la Paix (Namur) thales.math.fundp.ac.be (Internet

i.d. 138.48.4.14, in the directory cute). We request that the userid is given

as the password. This will serve to identify those who have obtained a copy

via ftp.

Secondly, the package can be obtained on a floppy disk or magnetic tape at a

minimal price, intended to recoup the costs of media, packaging, preparation

and courier delivery. Potentially interested parties should contact Ph. Toint

to obtain a suitable order form.

Ingrid Bongartz bongart@watson.ibm.com

Andy Conn arconn@watson.ibm.com

Nick Gould gould@cerfacs.fr

Philippe Toint pht@math.fundp.ac.be

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

From: tschoban@siam.org

Date: Thu, 11 Nov 93 09:18:26 EST

**Subject: SIMAX 15-1 Table of Contents**

Table of Contents

SIMAX 15-1, January 1994

Scaling Matrices to Prescribed Row and Column Maxima

Uriel G. Rothblum, Hans Schneider, and Michael H. Schneider

A Completed Theory of the Unsymmetric Lanczos Process and Related

Algorithms, Part II

Martin H. Gutknecht

A Bottom-Up Inductive Proof of the Singular Value Decomposition

C.-T. Pan and Kermit Sigmon

Predicting Structure in Sparse Matrix Computations

John R. Gilbert

Circulant Preconditioned Toeplitz Least Squares Iterations

Raymond H. Chan, James G. Nagy, and Robert J. Plemmons

Inverse of Strictly Ultrametric Matrices are of Stieltjes Type

Servet Martinez, Gerard Michon, and Jaime San Martin

A Linear Algebra Proof that the Inverse of a Strictly Ultrametric

Matrix Is a Strictly Diagonally Dominant Stieltjes Matrix

Reinhard Nabben and Richard S. Varga

Generalized Displacement Structure for Block-Toeplitz, Toeplitz-

Block, and Toeplitz-Derived Matrices

T. Kailath and J. Chun

On the Controllability of Matrix Pairs (A, K) with K Positive

Semidefinite, II

David Carlson

Reduction of a Transfer Function via an Observability Matrix

Stephen Barnett

The Schur Algorithm for Matrix-Valued Meromorphic Functions

Reuven Ackner, Hanoch Lev-Ari, and Thomas Kailath

Reducibility Condition of a Class of Rational Function Matrices

Kai Sheng Lu and Jia Ning Wei

Fast Plane Rotations with Dynamic Scaling

Andrew A. Anda and Haesun Park

Positive Definiteness and Stability of Interval Matrices

Jiri Rohn

ESPRIT Direction-of-Arrival Estimation in the Presence of Spatially

Correlated Noise

Haesun Park

Finding the Best Regression Subset by Reduction in Nonfull-Rank

Cases

Alan H. Feiveson

Numerical Solution of the Eigenproblem for Banded, Symmetric

Toeplitz Matrices

Susan L. Handy and Jesse L. Barlow

A Note on Jacobi Being More Accurate Than QR

Walter F. Mascarenhas

Large Least Squares Problems Involving Kronecker Products

Donald W. Fausett and Charles T. Fulton

A Shifted Block Lanczos Algorithm for Solving Sparse Symmetric

Generalized Eigenproblems

Roger G. Grimes, John G. Lewis, and Horst D. Simon

Factoring Symmetric Indefinite Matrices on High-Performance

Architectures

Mark T. Jones and Merrell L. Patrick

Computation of Stable Invariant Subspaces of Hamiltonian Matrices

R. V. Patel, Z. Lin, and P. Misra

Sparsity Patterns with High Rank Extremal Positive Semidefinite

Matrices

J. William Helton, Daniel Lam, and Hugo J. Woerdeman

Norms of Hadamard Multipliers

Carl C. Cowen, Michael A. Dritschel, and Richard C. Penney

Cyclic Reduction for Special Tridiagonal Systems

S. Bondeli and W. Gander

Dynamic Condition Estimation and Rayleigh--Ritz Approximation

Ping Tak Peter Tang

On the Structure of Generalized Singular Value and QR

Decompositions

Bart De Moor

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

From: Barry Koren <Barry.Koren@cwi.nl>

Date: Fri, 12 Nov 1993 11:15:58 +0100

**Subject: New book: Numerical Methods for Advection-Diffusion Problems, etc**

New book:

--------

Numerical Methods for Advection-Diffusion Problems,

Notes on Numerical Fluid Mechanics, Vol. 45,

(C.B. Vreugdenhil, B. Koren, eds.),

Vieweg Verlag, Braunschweig (1993),

ISSN 0179-9614, ISBN 3-528-07645-3.

# pages: 373, price: DM 138,--

Abstract:

The book contains a comprehensive overview of numerical methods to solve

advection-diffusion problems, occurring in many fields of flow transport

(water quality, atmospheric environment, industrial flows, etc.). All major

classes of discretization methods are discussed: finite-difference (upwind

and centered, low- and high-order, linear and nonlinear), finite-volume,

finite-element, spectral, semi-Lagrangian and fluctuation-splitting methods.

Further, two types of modern iterative methods are considered: conjugate

gradients and multigrid. The numerical methods are subjected to comparative

tests. Conclusions are drawn concerning the performance on points as accuracy,

positivity, conservation and cost. Using this information, readers have the

possibility to select a method according to their specific needs.

Chapters:

1. Introduction --------------------------------------------- C.B. Vreugdenhil.

2. Linear central finite-difference methods ----------------- C.B. Vreugdenhil.

3. Linear upwind biased methods ------------ J.C.H. van Eijkeren, B.J. de Haan,

G.S. Stelling, Th.L. van Stijn.

4. Some classical non-linear schemes for advection -------------- M. Pourquie'.

5. A robust upwind discretization method for advection,

diffusion and source terms --------------------------------------- B. Koren.

6. Essentially non-oscillatory (ENO) schemes ------------------ F.H. Walsteijn.

7. Spectral methods for advection-diffusion problems ------- L.J.P. Timmermans,

F.N. van de Vosse.

8. Finite element methods for advection-diffusion equations --------- A. Segal.

9. Backward semi-Lagrangian methods: an adjoint

equation method: -------------------------------------- J.C.H. van Eijkeren.

10. Forward semi-Lagrangian methods: the second moment method ----- J.M. de Kok.

11. The fluctuation splitting method ------------------------------- R. Struijs.

12. Optimal iteration methods for large linear systems of

equations: ---------------------------- G.L.G. Sleijpen, H.A. van der Vorst.

13. Introduction to multi-grid --------------------------------- R.P. Stevenson.

14. Multigrid and advection ------------------------------------- P.M. de Zeeuw.

15. Evaluation of the numerical results ------------ B. Koren, C.B. Vreugdenhil.

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

From: flores@siam.org

Date: Fri, 12 Nov 93 12:58:15 EST

**Subject: 1994 SIAM Annual Meeting**

Announcing...

1994 SIAM Annual Meeting

July 25-29, 1994

Sheraton Harbor Island East

San Diego, California

Plus...

Symposium on Control Problems in Industry

July 22-23, 1994

Third SIAM Forum on Industrial and Applied Mathematics

July 23, 1994

Organizing Committee Chair: Barbara L. Keyfitz, University

of Houston

Deadline for submission of minisymposium proposals:

December 27, 1993

Deadline for submission of contributed abstracts:

January 24, 1994

A hard copy of the call for papers for the meeting is now

available. Likewise an electronic version of it. To receive

either copy, contact:

SIAM Conference Department

E-Mail Address: meetings@siam.org

Telephone: 215-382-9800

Fax: 215-386-7999

Plain TeX or LaTeX macros for submitting abstracts are also

available by contacting SIAM at the same address.

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

From: Dean Schulze <schulze@asgard.lpl.arizona.edu>

Date: Fri, 12 Nov 1993 19:11:59 -0700 (MST)

**Subject: Algorithm analysis and efficiency**

Stefano Foresti made some thoughtful comments on the need

for a balanced approach when solving numerical problems (NA Digest,

v93, #41, 11-7-93). I agree with his statement

" A "balanced" knowledge of all aspects of a computational

problem, and their interactions, is necessary to compute a

reliable and efficient solution. This includes physical problem,

input data, continuous model, discrete model, numerical algorithms,

finite arithmetic, architecture, language and software."

However, there is a cost associated with producing such a reliable

and efficient solution: the time required to analyze how all of these

factors affect obtaining a solution. This too must be considered when

discussing efficiency.

Foresti analyzed an example that I had given previously:

>Let's consider an example in a previous contribution:

> r=exp(exp(-1.0/cos(chi)))

>The probability that chi == pi/2, hence cos(chi) == 0 is very slim,

>because the approximate representation of pi is not = to real value of

>pi. However, it is possible to show that in simple precision variations

>up to 4% of chi around around pi/2 would all output r=1. Hence this

>computation may forgive a superficial programmer, because it generates

>stable results. Nevertheless, that expression is very expensive

>(1 division and 2 exponentials) and it is very inefficient and unwise

>to compute in an incremental loop, when the result is predictable.

>Therefore, the confident use of this formula in the range of exceptions

>may indicate more laziness then mastery.

Understanding the trade-off between computational expense and precision

is part of the numerical analyst's art. However, unless you're paying

for CPU time or have to wait for the result, the cost of this computation

is zero.

The previous analysis is incomplete because it doesn't include the

cost of the numerical analyst's time. When this consideration is included

it may turn out to be inefficient to optimize an algorithm that is only

used occaisonally.

In developing software for my research I use algorithms that are clear

and simple implementations of the underlying physics, and I don't analyze

their efficiency unless improved performance is needed. Software developed

in a research environment gets changed so often that clarity and generality

are important, but efficiency analysis can rarely be justified. In the

example above, I allow IEEE arithmetic to give me a reliable result because

the extra time involved is probably undetectable while sitting at a

workstation. While reliability is important to me, optimizing algorithms

is usually a waste of time.

Another drawback to analyzing algorithms for someone whose primary

job is something other than code development is that it distracts you

from your primary job, which often is interpreting the results (as opposed

to just obtaining the results).

Of course certain kinds of code development, such as numerical

libraries, must be as efficient and robust as possible because they are

heavily used. Without comprehensively designed, analyzed, and tested

libraries users like myself wouldn't have reliable and efficient tools,

and we would be constantly distracted from our primary jobs by exceptions.

A computational scientist should be able to do a comprehensive analysis

of the various factors that affect performance. However, in many cases it

doesn't pay to do it.

Dean Schulze

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

From: Nick Trefethen <lnt@cs.cornell.edu>

Date: Sat, 13 Nov 93 10:44:34 -0500

**Subject: Upstate Numerical Analysis Day -- Cornell University**

UPSTATE NUMERICAL ANALYSIS DAY

Cornell University

Ithaca, NY

Thursday, 9 December 1993

On Thursday, 9 December, the Cornell Computer Science Department and

Cornell Theory Center will host an informal get-together for numerical

analysts. The following half-hour talks are currently scheduled:

Tom Coleman or Yuying Li, title to be announced

Toby Driscoll, "Interactive Schwarz-Christoffel mapping in Matlab"

Arieh Iserles, "Qualitative analysis of discretized ODEs"

Dirk Laurie, "Imperfect periodizing of functions for numerical

integration -- MUST all derivatives vanish?"

Saul Teukolsky, "Numerical Recipes: Physicists versus Numerical Analysts?"

Anne Trefethen, "Parallel Matlab and pipe Poiseuille pseudospectra"

Charlie Van Loan, "An eigenvalue problem from adaptive optics"

Steve Vavasis, "An accelerated interior point method based on

layered least-squares"

If you're in the area, or feel like visiting the area, please come!

Please contact me if you are likely to attend, so that we can get an

idea of numbers. For hotel reservations and other local information,

contact Cindy Robinson (cindy@cs.cornell.edu, 607-255-0985).

Nick Trefethen

LNT@cs.cornell.edu

(607) 255-4222

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

End of NA Digest

**************************

-------