- Today's Editor:
- Cleve Moler
- The MathWorks, Inc.
- moler@mathworks.com

- Householder Fellow in Scientific Computing
- Change of Address for Kathy Brenan
- A Query about Block Matrices
- Eigenvalues of An Integral Operator
- Multisplitting Algorithm Needed
- New Version of ARPACK Available for Large Eigenproblems
- Past and Forthcoming Workshops at CERFACS
- European Conference on Parallel Processing
- Time-Frequency and Time-Scale Methods for Economics and Finance
- Proceedings of AMCA-95 Conference
- Graduate Fellowships in CAM at UT-Austin
- Position at Weidlinger Associates

**URL for the World Wide Web:**
http://www.netlib.org/na-net/na_home.html
-------------------------------------------------------

From: Esmond Ng <esmond@msr.EPM.ORNL.GOV>

Date: Tue, 21 Nov 1995 09:47:45 -0500

**Subject: Householder Fellow in Scientific Computing**

Ren-Cang Li has joined the Mathematical Sciences Section at the Oak

Ridge National Laboratory as the 1995 Householder Fellow in Scientific

Computing. Ren-Cang will receive his Ph.D. in Mathematics from the

University of California at Berkeley. His research interests include

numerical linear algebra and numerical solution of ordinary

differential equations.

The Fellowship honors the late Alston S. Householder, founding Director

of the Mathematics Division (now Computer Science and Mathematics

Division) at ORNL, and recognizes his seminal research contributions to

the fields of numerical analysis and scientific computing. The

Householder Fellowship is supported by the Office of Mathematical,

Information, and Computational Sciences of the U.S. Department of

Energy.

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

From: Kathy Brenan <brenan@mustang.aero.org>

Date: Wed, 22 Nov 1995 11:17:45 -0800

**Subject: Change of Address for Kathy Brenan**

I have transferred with the Aerospace Corporation to their

Engineering Group located in Herndon, VA. My new address is

Kathryn Brenan

The Aerospace Corporation

The Hallmark Building, Suite 187

13873 Park Center Road

Herndon, VA 22071

(703)318-5410

brenan@mustang.aero.org

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

From: Francois Robert <Francois.Robert@imag.fr>

Date: Mon, 20 Nov 1995 09:19:57 +0100

**Subject: A Query about Block Matrices**

I have below a nice result, and also a nice question for the na-neters:

B is an (n by n) nonnegative matrix decomposed into blocks Bij

with square diagonal blocks Bii:

B11... B1k

B = ..........

Bk1... Bkk

Moreover, we are given a p-uple p=(p1, p2,...pk) of positive integers pi,

and one defines the matrix Mp, with blocks Mij, as follows:

Mii = (Bii)^pi

Mij = (I+Bii+(Bii)^2+...(Bii)^(pi-1))*Bij

(this matrix Mp comes from parallel asynchronous iterations on a linear

fixed-point problem with matrix B)

1)a nice result (a Stein-Rosenberg-type theorem)

We have the same result between B and Mp than between the usual Jacobi and

Gauss-Seidel procedures for M-matrices (ro is the spectral radius):

(i) if ro(B)=0, then ro(Mp)=0

(ii) if ro(B) is less than one, then ro(Mp) is less or equal to ro(B),

and greater or equal to ( ro(B) )^(Max pi) (from which (i) follows)

(iii) if ro(B) is equal to 1, the same for ro(Mp)

(iv) if ro(B) is greater than one, then ro(Mp) is greater or equal to ro(B)

and less or equal to ( ro(B) )^(Max pi)

Moreover, the same result is valid for boolean matrices (with, of course,

boolean operations and spectral radii)

Please note that Mp is NOT a block-Gauss-Seidel matrix of B.

Did you have you already seen this kind of result in the litterature?

2)a nice question

In the case where ro(B)=0,

(equivalently, there exists a positive integer q, less or equal to n,

such that B^q = 0 (the null matrix), or B can be taken strictly triangular)

The conjecture is that we have also:

(Mp)^q = 0

(which gives again ro(Mp)=0)

The result is quite simple for constant pi, but I'd like to proove

it in the general case.

Thanks a lot for any help,

F.Robert

Francois ROBERT, ENSIMAG, BP 53 F-38041 Grenoble Cedex 9

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

From: Burt Simon <bsimon@tiger.cudenver.edu>

Date: Tue, 21 Nov 1995 10:56:20 -0700

**Subject: Eigenvalues of An Integral Operator**

HOW FAST DO THE EIGENVALUES APPROACH ZERO ?

Let A be the real, positive definite, symmetric operator given by

$ Af = \int_0^1 r(x,y)f(y) dy $

What can be said about the rate that the eigenvalues of A approach 0 ?

A related question concerns the finite approximation of A based on

the evenly spaced mesh on [0,1] with n points. Let $\lambda_n$ be

the smallest eigenvalue of the approximate operator, $A_n$. How

does $\lambda_n$ approach 0 ?

Our numerical experiments seem to imply that when

$ r(x,y) = exp(-k|x-y|) $

$\lambda_n$ is order $1/n$ for any k, and when

$ r(x,y) = exp(-k(x-y)^2) $

$\lambda_n$ decreases exponentially fast. Any help would be greatly

appreciated. Thanks,

Burt Simon

Dept. of Mathematics

University of Colorado at Denver

bsimon@tiger.cudenver.edu

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

From: Praveen Sharma <sharma@pnge.PSU.EDU>

Date: Tue, 21 Nov 1995 13:19:04 -0500

**Subject: Multisplitting Algorithm Needed**

Hi:

I am looking for parellel algorithm/code for multisplitting by

BSOR (or any other method). Can anyone give me directions?

Praveen

sharma@pnge.psu.edu

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

From: Dan Sorensen <sorensen@caam.rice.edu>

Date: Wed, 22 Nov 1995 16:52:59 -0600 (CST)

**Subject: New Version of ARPACK Available for Large Eigenproblems**

NEW VERSION OF ARPACK AVAILABLE

ARPACK is a collection of Fortran77 subroutines for solving

large scale eigenvalue problems.

The codes are available by anonymous ftp from

ftp.caam.rice.edu

or by connecting directly to the URL

ftp://ftp.caam.rice.edu/pub/people/sorensen/ARPACK

The package is designed to compute a few eigenvalues and corresponding

eigenvectors of a general n by n matrix A. It is most appropriate for large

sparse or structured matrices A where structured means that a matrix-vector

product w <- Av requires order n rather than the usual order n**2

floating point operations. This software is based upon an algorithmic variant

of the Arnoldi process called the Implicitly Restarted Arnoldi Method (IRAM).

When the matrix A is symmetric it reduces to a variant of the Lanczos process

called the Implicitly Restarted Lanczos Method (IRLM). These variants

may be viewed as a synthesis of the Arnoldi/Lanczos process with the

Implicitly Shifted QR technique that is suitable for large scale problems.

For many standard problems, a matrix factorization is not required. Only

the action of the matrix on a vector is needed.

ARPACK software is capable of solving large scale symmetric, nonsymmetric,

and generalized eigenproblems from significant application areas.

The software is designed to compute a few (k) eigenvalues with user specified

features such as those of largest real part or largest magnitude.

Storage requirements are on the order of n*k locations. No auxiliary storage

is required. A set of Schur basis vectors for the desired k-dimensional

eigen-space is computed which is numerically orthogonal to working precision.

Numerically accurate eigenvectors are available on request.

Important Features:

Reverse Communication Interface.

Single and Double Precision Real Arithmetic Versions for

Symmetric, Non-symmetric, Standard or Generalized Problems.

Single and Double Precision Complex Arithmetic Versions

for Standard or Generalized Problems.

Routines for Banded Matrices - Standard or Generalized Problems.

Routines for The Singular Value Decomposition.

Example driver routines that may be used as templates to

implement numerous Shift-Invert strategies for all problem types,

data types and precision.

TO GET THE SOFTWARE: Connect by ftp to ftp.caam.rice.edu and login

as anonymous. Then change directories to

pub/people/sorensen/ARPACK

or connect directly to the URL as described above

and follow the instructions in the README file in that directory.

Users of previous versions of ARPACK are urged to replace what they

have been using with this new version. This new software has improved

numerical performance and many new features.

Authors: R. Lehoucq, D. Sorensen, P. Vu, C. Yang

For further information send e-mail to

sorensen@caam.rice.edu

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

From: Jacko Koster <Jacko.Koster@cerfacs.fr>

Date: Fri, 24 Nov 1995 16:01:50 +0100

**Subject: Past and Forthcoming Workshops at CERFACS**

THE INTERNATIONAL LINEAR ALGEBRA YEAR AT CERFACS

The first two of a series of four workshops of the International Linear

Algebra Year were held September 26-29 (Direct Methods) and October 17-20,

1995 (Eigenvalues and Beyond). The workshops were organized by CERFACS and

took place in Toulouse, France. Each workshop was attended by about 90

academic and industrial researchers. From their reactions we conclude that

both meetings were a great success and that they attained their objectives

as well as the expectations of the participants.

For both workshops, URLs exist that provide links to abstracts, posters and

papers that have been made available by the speakers:

*** Direct Methods, September 26-29, 1995

URL : http://www.cerfacs.fr/~wlay/LAY/direct.html

*** Eigenvalues and Beyond, October 17-20, 1995

URL : http://www.cerfacs.fr/~wlay/LAY/eigen.html

The two forthcoming workshops of the ILAY are scheduled for next year.

The first workshop is:

*** Linear Algebra in Optimization, April 22-25, 1996

URL : http://www.cerfacs.fr/~wlay/LAY/opti.html

This workshop will be held in Albi, a town not far from Toulouse.

The second workshop is:

*** Iterative Methods, June 10-13, 1996

URL : http://www.cerfacs.fr/~wlay/LAY/iter.html

More information about these workshops will appear in future issues of

the NA-Digest.

An interesting feature of the ILAY is the visitor programme that

enables participants and speakers to visit CERFACS before or after

the workshops or for longer periods during the year. More information

about this and other ILAY features can be obtained in any of the

following ways:

- ILAY home page,

URL: http://www.cerfacs.fr/~wlay/LAY/lay.html

- anonymous ftp to ftp.cerfacs.fr, directory

/pub/algo/workshops/ILAY/Info

- email to wlay@cerfacs.fr

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

From: Yves Robert <Yves.Robert@lip.ens-lyon.fr>

Date: Mon, 20 Nov 1995 10:14:38 +0100

**Subject: European Conference on Parallel Processing**

CALL FOR PAPERS

EURO-PAR'96

Ecole Normale Superieure de Lyon, France

August 27-29, 1996

Euro-Par is THE European conference on parallel processing. It is the

merging of CONPAR-VAPP and PARLE, which were already two major

events in the field. The goal of Euro-Par'96 is to gather people

interested in any aspects of parallel computing and architectures.

Euro-Par'96 is split into workshops which focus on specific domains.

Each workshop is chaired by a major leading researcher in the field.

You are thereby ensured to have the best opportunity to meet

colleagues and to discuss on-going science. Furthermore, there are

invited talks to hear about hot topics, and, since many workshops

run concurrently, you can meet a large spectrum of people and

broaden your expertise. Workshops duration will be between 1/2

day up to 2 days depending on the number of selected papers.

All the accepted papers will be published in the collection Lecture Notes

in Computer Science by Springer-Verlag. The proceedings of Euro-Par'96

will contain full papers (12 pages), short papers (8 pages), and

poster papers (4 pages).

WORKSHOP LIST AND WOKSHOP CHAIRS:

01 Programming environment and tools

Jack Dongarra, Knoxville, USA

02 Routing and communication in interconnection networks

Robert Cypher, Baltimore, USA

03 Automatic parallelization and high performance compilers

Chris Lengauer, Passau, D

04 Distributed systems and algorithms

Friedemann Mattern, Darmstadt, D

05 Parallel languages, programming and semantics

Ian Foster, Argonne, USA

06 Parallel non numerical algorithms

Burkhard Monien, Paderborn, D

07 Parallel numerical algorithms

Ian Duff, Didcot, UK

08 Parallel DSP and image processing

Larry Davis and Joseph Jaja, College Park, USA

09 VLSI design automation

Francky Catthoor, Leuven, B

10 Computer arithmetic

Jean-Marc Delosme, Yale, USA

11 High performance computing and applications

Wolfgang Gentzsch, Genias, D

12 Theory and models of parallel computing

William McColl, Oxford, UK

13 Parallel computer architecture

Chris Jesshope, Surrey, UK

14 Networks and ATM

Paul Kuehn, Stuttgart, D

15 Optics and other new technologies for parallel computation

Ahmed Louri, Tucson, USA

16 Neural networks

Michel Verleysen, Louvain, B

17 Scheduling and load balancing

Apostolos Gerasoulis, Rutgers, USA

18 Critical systems

Amir Pnueli, Weizman, Is

19 Performance evaluation

Francois Baccelli, Nice, F

20 Instruction level parallelism

Guang R. Gao, Montreal, CA

21 High-level and meta-level control in parallel symbolic programs

Jean-Pierre Briot, Paris, F

22 Parallel and distributed databases

Erhard Rahm, Leipzig, D

SUBMISSION:

Submitted papers should be no longer than 15 pages.

The cover page must clearly indicate the names, addresses,

affiliations, and electronic addresses of the authors. The workshop

number and the workshop name related to each submitted paper

must also be clearly indicated on the cover page.

Authors are encouraged to submit PostScript versions of their papers

electronically at europar96@lip.ens-lyon.fr. Authors not having

access to electronic facilities are invited to send 6 copies of their

papers and a cover letter to :

Euro-Par'96

LIP - CNRS

Ecole Normale Superieure de Lyon,

F-69364 Lyon Cedex 07, France

Phone: +33 72 72 80 37, Fax: +33 72 72 80 80

IMPORTANT DATES:

Electronic submission February 18, 1996

Non electronic submission February 4, 1996

Notification of acceptance/rejection May 10, 1996

Camera-ready of accepted papers June 10, 1996

INFORMATION:

Please email to europar96@lip.ens-lyon.fr for any

questions related to Euro-Par'96. Other information is available on

W3 at : http://www.ens-lyon.fr/LIP/europar96

Organization: Euro-Par'96 is organized by LIP (Laboratoire de

l'Informatique du Parallelisme URA CNRS 1398) and will take place

at the Ecole Normale Superieure de Lyon.

General chair: Pierre Fraigniaud

Program co-chair: Luc Bouge' and Yves Robert

Organization chair: Anne Mignotte

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

From: Seth Greenblatt <S.A.Greenblatt@reading.ac.uk>

Date: Tue, 21 Nov 1995 16:13:20 +0000 (GMT)

**Subject: Time-Frequency and Time-Scale Methods for Economics and Finance**

CALL FOR PAPERS

Session on

TIME-FREQUENCY AND TIME-SCALE METHODS FOR ECONOMICS AND FINANCE

Society for Computational Economics

Second International Conference on

Computing in Economics and Finance

Geneva, Switzerland, 26-28 June 1996

Economic and financial data are often analysed in either the time

domain or the frequency domain. If the data is stationary, then these

are useful approaches. However, it is often the case that economic

and financial data are non-stationary, or non-homogeneous in some sense.

In these cases, it is instructive to look at the data either on the

time-frequency plane or on multiple scales over time. Time-frequency

and time-scale methods allow us to do this. We can observe the

changes in behaviour over time.

Papers are sought that address these issues, as they relate to

economics and finance, in areas including, but not limited to:

wavelets, wavelet packets, time-frequency distributions (Wigner-Ville,

etc.), atomic decompositions, matching pursuit, basis pursuit,

windowed Fourier methods, and Gabor decompositions.

Papers and abstracts for this session should be sent to the session

organiser:

Dr. Seth A. Greenblatt

Director, Centre for Quantitative Economics and Computing

Department of Economics

Faculty of Letters and Social Sciences

University of Reading

PO Box 218

Whiteknights

Reading RG6 6AA

ENGLAND

Email: S.A.Greenblatt@rdg.ac.uk

FAX: +44(1734)750236

Phone: +44(1734)875123, Ext. 4059

Abstracts of up to two pages are due by 20th January 1996, and final

papers are due by 20th March 1996. Abstracts may be sent by post,

email (text, postscript, or LaTeX), or FAX. Final papers may be sent

by post or email (postscript or LaTeX).

For more information regarding the Society or the Conference, please

consult the Society for Computational Economics Homepage:

http://www.unige.ch/ce

Dr. Seth A. Greenblatt

Director, Centre for Quantitative Economics

and Computing

Department of Economics

University of Reading

S.A.Greenblatt@rdg.ac.uk

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

From: Valery P. Il'in <ilin@comcen.nsk.su>

Date: Tue, 21 Nov 95 17:45:34 +0700

**Subject: Proceedings of AMCA-95 Conference**

For Researches, Universities, Libraries

Announcement

Proceedings of AMCA-95 Conference

The International Conference "Advanced Mathematics, Computations and

Applications" has been hold in Novosibirsk, June 20-24, 1995.

The Proceedings will be published by Computing Center SD RAS

(Novosibirsk) in December, 1995, with the support of Russian Foundation

of Basic Research (RFBR) and Italien C.N.R (Consiglio Nazionale Delle

Ricerche).

The Proceedings are edited by Academicians A.S.Alekseev (Novosibirsk)

and N.S.Bakhvalov (Moscow).

The contents of Proceedings consist of 85 selected artictles on the

following topics of the Conference:

- Approximations and Applications

- Circulation of Atmosphere and Ocean

- Computational Algebra

- Computer Architectures \& Technologies

- Domain Decomposition \& Multigrid Methods

- Incorrect and Inversed Problems

- Industrial Mathematics

- Mechanics of Continuous Media

- Statistical Simulation

The list of authors includes invited speakers (A.S.Alekseev, O.Axelsson,

N.S.Bakhvalov, V.P.Dymnikov, R.Ewing, H.Fujita, Yu.A.Kuznetsov,

M.M.Lavrentiev, E.Magenes, A.S.Sarkisyan, J.Sundermann, V.S.Vladimirov)

and contributors - wellknown and young scientists from Russia, France,

Germany, Italy, Japan, USA and other countries.

The price of the book (800 pages, hard cover) is 99$.

The Proceedings will be distributed free to the participants of AMCA-95

Conference.

If you are inerested to have the Proceedings of AMCA-95 Conference,

please contact:

AMCA--95 Organizing Committee

Computing Center Russian Ac.\ Sci.,

Prospect Lavrentieva, 6

630090, Novosibirsk 90, RUSSIA

Tel.: (007)3832--351157,

Fax: (007)3832--357942

E-mail: lida@comcen.nsk.su

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

From: Robert van de Geijn <rvdg@cs.utexas.edu>

Date: Tue, 21 Nov 1995 09:58:36 -0600

**Subject: Graduate Fellowships in CAM at UT-Austin**

The Computational and Applied Mathematics (CAM) program is an

interdisciplinary graduate program at the University of Texas at

Austin. This exciting program draws from the strengths of the various

departments and colleges on campus. Associated with CAM is the Texas

Institute for Computational and Applied Mathematics (TICAM).

As part of this program, twelve fellowships were created at a level of

$25,000 per year for qualified students. While these fellowships are

restricted to US citizens, a number of other funding opportunities

also exist, including TAships and RAships in participating

departments, as well as a few other fellowships.

For more information, see our web page:

http://www.ticam.utexas.edu

call (512) 471-7386, or contact our Graduate Coordinator, Nita Cooke

(nita@ticam.utexas.edu).

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

From: Victor Pereyra <victor@wai.com>

Date: Wed, 22 Nov 95 11:15:42 PST

**Subject: Position at Weidlinger Associates**

POSITION AVAILABLE

Weidlinger Associates, Consulting Engineers, has an opening in its Los Altos,

California office, to support the development and maintenance of commercial

software in the areas of Non-Destructive Testing and Geophysical Oil

Prospecting and Reservoir Characterization.

Ideally, the candidate should have a MS degree in applied mathematics,

scientific computing, physics, geophysics, applied mechanics or engineering

with a strong applied mathematics and computing background, or several years

of practical experience in areas not covered by his/her formal education.

We value communications skills highly.

Any and all of the abilities listed below are of interest:

1. Knowledge of Ultrasound Testing methods for inspecting nozzles, safe ends

and other shapes; mathematical abilities to develop geometric models using

analytic functions, B-splines and other interpolation functions and to

implement ray tracing in such models.

2. Knowledge of elastic wave propagation simulation, geological modeling,

seismic data processing, and other related matters as they pertain to petroleum

exploration and reservoir characterization.

3. Development and maintenance under both UNIX and DOS/WINDOWS of large,

complex, computer modeling packages. This includes graphics, user interfaces,

and programming languages, specifically, FORTRAN, C and C++.

4. Interest in and ability to provide telephone or e-mail consultation and

support to clients and licensees of the various software products, and in

developing and performing demonstrations for clients and in trade shows.

Citizenship or permanent residency is required.

Please respond to: victor@wai.com, with a short statement establishing your

credentials and current address. DO NOT SEND FULL RESUMES OVER e-mail.

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

End of NA Digest

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

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