NA Digest Sunday, June 25, 2000 Volume 00 : Issue 26

Today's Editor:
Cleve Moler
The MathWorks, Inc.

Submissions for NA Digest:

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Information about NA-NET:

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URL for the World Wide Web:

From: Gerbi Stephane <>
Date: Mon, 19 Jun 2000 16:21:50 +0200
Subject: Problem about Nonsquare Linear System

Dear Na-Netters,
I would like to submit a problem that chemists from my University
gave to me.
A be an m by n matrix with m < n. (m rows and n columns),
b be a 1 by m real vector, (vector in R^m)
(x_i) for i = 1,p be p n by 1 real vectors (vector in R^n).

I would like to know if it exists a numerical method to solve
the linear system A x = b. Since they "know" where the solution
must live and because the system is under determine, they add the
condition of finding a solution of the linear system x such that
Sum_i^p Norm(x-x_i)^2 is minimum.
They told me that a solution exists.

If such a numerical exists, can you tell me if a package of program
exists too.

Best regards,

Stephane GERBI
Universite de Savoie,
Laboratoire de Mathematiques
Campus Scientifique
73376 Le Bourget du Lac Cedex
e-mai l:,
phone : +33.(0)
fax : +33.(0)


From: Nasir Haniffa <>
Date: Fri, 23 Jun 2000 08:48:31 +0900
Subject: Eigenvalues of Tridiagonal Matrices

I am PhD student in Numerical Analysis and I would like to know
(or any reference ) if there is any closed form for the eigenvalues
of the symmetric tridiagonal matrix of the form which I denote for ease
Tri(b, c(a)c , b) where the subdiagonals are formed by 'b' and the main
diagonal is formed by 'a' with first and last values by 'c'.

When c = a, it is the usual tridiagonal matrix arising from
finite differences for which the eigenvalues are known
and when c = a/2, it is the matrix of finite element with
Neumann BC. I want to know the eigenvalues for an arbirary c.

Thank you

Nasir Haniffa


From: John Hench <>
Date: Mon, 19 Jun 2000 10:07:31 -0700
Subject: Change of Address for John J. Hench

John Hench has new work coordinates:

Dr. John J. Hench
Voyan Technology
3255-7 Scott Blvd
Santa Clara, CA 95054

Phone: (408) 450-4239


From: Nick Trefethen <>
Date: Wed, 21 Jun 2000 15:39:30 +0100 (BST)
Subject: Meeting on Random Matrices at Oxford

An informal meeting on "(Pseudo)spectra of random nonhermitian
matrices" will be held Friday June 30 at the Oxford University
Computing Laboratory. All are welcome. For information see

Nick Trefethen


From: ISSAC 2001 <>
Date: Sun, 18 Jun 2000 14:30:22 -0400 (EDT)
Subject: Symposium on Symbolic and Algebraic Computation

International Symposium on Symbolic and Algebraic Computation (ISSAC 2001)
July 22-25, University of Western Ontario, London, Ontario, Canada.

See: Email:

ISSAC is the yearly premier international symposium in Symbolic and
Algebraic Computation. It provides an opportunity to learn of new
developments and to present original research results in all areas of
symbolic mathematical computation.
Recent advances are communicated through its refereed conference
proceedings (available at the conference), prestigious invited talks,
tutorials, product exhibits, poster presentations and other activities.

We look forward to seeing you at the conference!

Conference Committee

General Chair: Erich Kaltofen (NCSU, Raleigh, USA)
Program Committee Chair: Gilles Villard (CNRS-IMAG, Grenoble, France)
Local Arrangements Chair: Greg Reid (UWO, London, Ontario, Canada),,


From: Karol Mikula <>
Date: Sat, 24 Jun 2000 13:52:03 +0200
Subject: Conference in Slovakia on Scientific Computing

Conference on Scientific Computing
High Tatra Mountains , September 10 - 15, 2000

Scientific Programme Committee:
E.Baensch (Bremen), P.Brunovsky (Bratislava), G.Dziuk (Freiburg),
W.Jaeger (Heidelberg), J.Kacur (Bratislava), J.Komornik (Bratislava),
G.Meyer (Atlanta), K.Mikula (Bratislava), M.Rumpf (Bonn),
J.A.Sethian (Berkeley), M.Vajtersic (Bratislava)

The main topics of the conference:

* computational fluid dynamics
* heat and mass transfer
* flow in porous media
* image processing and computer vision
* computational finance
* free boundary problems
* inverse problems
* data analysis and pattern recognition
* scientific visualization
* software for scientific computations.

Plenary speakers:
E.Baensch (Bremen), M. Benes (Prague),
Gui-Qiang Chen (Northwestern University, Evanston),
C.M. Elliott (Brighton), H.-J. Diepers (Aachen),
G.Dziuk (Freiburg), R. E. Ewing (Texas A&M),
K.Johannsen (Heidelberg), J. Kacur (Bratislava),
J.Komornik (Bratislava), M. Kratka (Chicago), D. Kroener (Freiburg),
R.Malladi (Berkeley), G. Meyer (Atlanta), T. Preusser (Bonn),
A.Sarti (Bologna/Berkeley), K. Siebert (Freiburg), J. Sethian (Berkeley),
Z.Strakos (Prague/Atlanta), R. Strzodka (Bonn), S. Turek (Dortmund),
D.W.Walker (Cardiff/Oak Ridge), J. Weickert (Mannheim)

If you are interested to attend and present a talk, it is still possible to
register at the conference web page:


From: Vladik <>
Date: Wed, 21 Jun 2000 18:20:28 -0600 (MDT)
Subject: Interfaces Between Fuzzy Sets and Interval Analysis

Fuzzy Sets and Systems
Special Issues: Interfaces Between Fuzzy Sets and Interval Analysis

Fuzzy set theory when restricted to sets of real numbers can be approached
via intervals and interval analysis. The intimate relationship between
interval analysis and fuzzy set theory is especially apparent in fuzzy
arithmetic, fuzzy optimization and some areas of fuzzy mathematical
analysis. A unimodal fuzzy membership function can be formed from a
continuum of intervals corresponding to alpha-levels or a continuum of
disconnected intervals for multi-modal fuzzy membership functions.
Intervals are one type of fuzzy set possessing a rectangular membership
function. This being the case, the issues and mathematical analysis
associated with fuzzy set theory and interval analysis are mutually
relevant. We invite papers on advances that clearly demonstrate the
interrelationships between fuzzy set theory and interval analysis.
In addition to new results in theoretical analysis, innovative
applications, and computer implementations, we invite insightful surveys.
All contributions must be original, not published elsewhere, and written
clearly in English. Please send 5 copies of your paper to the Guest
Editor before 01/01/2001.
Guest editor: Professor Weldon A. Lodwick
Department of Mathematics - Campus Box 170
University of Colorado at Denver
P.O. Box 173364
Denver, Colorado 80217-3364
Telephone: + 303 556-8462


From: Bette Byrne <>
Date: Thu, 22 Jun 2000 12:25:28 +0000
Subject: Conference on Numerical Methods in Fluid Dynamics

26 March - 29 March 2001


Invited Speakers include:

M J Baines (Reading)
T J Barth (NASA Ames)
J-D Benamou (INRIA-Rocquencourt)
F Brezzi (Pavia)
S M Deshpande (IISC- Bangalore)
C Farmer (Geoquest)
A J Keane (Southampton)
D Kroner (Freiburg)
R LeVeque (Washington)
R Rannacher (Heidelberg)
P L Roe (Michigan)
S J Sherwin (Imperial-London)
E Suli (Oxford)
N P Weatherill (Swansea)

For further information please contact

Mrs B Byrne
Oxford University Computing Laboratory
Wolfson Building, Parks Road
Oxford OX1 3QD, UK

Telephone: +44-1865-273883
Facsimile: +44-1865-273839
or see the Conference web site


From: C. Young <>
Date: Thu, 22 Jun 2000 09:29:48 -0400
Subject: ACM-SIAM Symposium on Discrete Algorithms

The Twelfth Annual ACM-SIAM Symposium on DISCRETE ALGORITHMS (SODA01)

Location: Wyndham City Center Hotel, Washington, D.C., U.S.A.

Dates: January 7-9, 2001

Reminder, the Call for Presentations deadlines for SODA01 are fast

To submit a LONG form abstract go to:
DEADLINE - JULY 7 no later than 5:00 PM EDT

To submit a SHORT form abstract go to:
DEADLINE - AUGUST 2, 2000 no later than 5:00 PM EDT

For additional information, contact SIAM Conference Department at


From: Jochen Hittler <Jochen.Hittler@IWR.Uni-Heidelberg.De>
Date: Fri, 23 Jun 2000 11:33:02 +0200
Subject: Modelling and Computation in Enviromental Sciences

International Conference on
Modelling and Computation in Enviromental Sciences

Oct 30 - Nov 2, 2000
Bad Herrenalb, Germany

IWR and STZ Technical Simulation
Research Network
WiR Baden-W=FCrttemberg
GAMM Fachauschu=DF ScientificComputing


This international conference was initiated in 1995 and acts as a focus
for recent advances and innovations being made in modelling and
computation of environmental processes.
The use of computer based models in this domain is still rapidly
expanding and new solutions are being developed. This symposium will
provide a forum for leading reseachers, scientists, and engineers. It
will also promote closer collaboration between scientists interested in
this field.

Conference topics

surface and subsurface hydrodynamics
surface and subsurface transport
microbial and reactive processes
flow in porous and fractured media
multiphase flow
parameter estimation and scale up
coastal flow
flow in rivers and channels
optimization techniques
numerical methods
density driven groundwater flow
flow and transport in the atmosphere

Invited speakers

S. Attinger, Z=FCrich
H. Class, Braunschweig
M. Espedal, Bergen
R. Ewing, College Station
G. Haase, Linz
T. Hou, Pasadena
C. Pruess, Berkeley
A. Quarteroni, Lausanne
W. Rodi, Karlsruhe
W. Sch=E4fer, Heidelberg
M. Wheeler, Austin


P. Bastian, Heidelberg
R. Helmig, Braunschweig
W. J=E4ger, Heidelberg
W. Kinzelbach, Z=FCrich
G. Wittum, Heidelberg

You need more information?


From: Karl Kunisch <>
Date: Wed, 21 Jun 2000 17:12:53 +0200
Subject: Postdoctoral Position at University of Graz, Austria.

POST-DOCTORIAL position at the Research Center on Control and Optimization
at the University of Graz, Austria.

Within the research Center on Control and Optimization at the Department
of Mathematics at the University of Graz a postdoctorial position in Applied
mathematics will become available.
The successfull candidate must have a strong background in numerical
analysis and differential equations. Additional experience in the areas
of Optimization and/or Navier Stokes equations is desirable. Good working
knowledge of the English language is essential.
We offer execallent working conditions in a lively research environment.
The position is expected to become available in the early fall. The
duration of the first contract will depend on the qualifications of the
candidate. It is expected that the position will be available for a
period of almost four years.
Interested candidates are encouraged to send an application with c.v.
and publication list to:

Prof. Karl Kunisch
Institut fuer Mathematik
Universitaet Graz
Heinrichstrasse 36
A-8010 Graz, Austria.


From: T. N. Phillips <>
Date: Fri, 23 Jun 2000 16:36:20 +0100
Subject: Postdoctoral Position at University of Wales, Aberystwyth


The Department of Mathematics has been awarded funding by the
EPSRC Process Engineering Programme for a project concerned with
the computation of non-Newtonian flows on heterogeneous
networks of processors.
There is a vacancy for a postdoctoral position commencing
1 September 2000 for a period of eight months. Further
grant applications are pending and the initial appointment
may be extended.
Applicants should hold, or expect to obtain in the near
future, a PhD in applied mathematics or engineering.
Familiarity with the spectral element method and/or
parallel computing hardware and message passing
software would be an advantage.

Applications should be made by sending a curriculum vitae and names
of two academic referees to Professor T.N. Phillips, Department
of Mathematics, University of Wales, Aberystwyth SY23 3BZ, UK.
Informal enquiries are welcomed either by phone
(+44 1970 622769) or by email (


From: Bo Zhang <>
Date: Tue, 20 Jun 2000 16:14:32 +0100
Subject: Postdoctoral Position at Coventry University

School of Mathematical and Information Sciences
Coventry University
Coventry, UK

Applications are invited for an 18-month postdoctoral position to work on
the EPSRC-funded project "Singular Integral Equations on Infinite Domains
with Application to Scattering by Infinite Lipschitz Surfaces". The aim of the
project is to develop a theoretical analysis of problems of acoustic and
electromagnetic scattering by effectively unbounded non-smooth (Lipschitz)

Applicants should have (or be close to completing) a PhD in applied analysis
and/or integral or partial differential equations. The ideal candidate should
also have experience of boundary integral equation methods and/or wave
scattering problems.

Further details may be obtained from
and informal enquiries cam also be made to Dr Bo Zhang
( or Dr Simon Chandler-Wilde

The post is on the RA1A scale, =A315,738 - =A324,012, depending on
qualifications, age and experience.


From: Kathy Boyer <>
Date: Mon, 19 Jun 2000 16:21:03 -0500
Subject: Postdoctoral Position at University of Minnesota

Institute for Mathematics and its Applications (IMA)

The IMA announces two-year Regular postdoctoral research memberships
effective September 1, 2001. The postdoctoral terms will include the
academic-year program on Mathematics in the Geosciences 2001-2002. The
second year of the appointment will provide a variety of options to enhance
career development, including participation in the 2002-2003 annual program
on Optimization.

IMA announces two-year Industrial postdoctoral research memberships. These
appointments are in addition to the regular IMA 2001-2002 postdoctoral
program Mathematics in the Geosciences and are funded jointly by NSF and
industry. They are designed to prepare mathematicians for research careers
involving industrial interaction. Industrial Postdoctorates will spend 50%
effort in the IMA program and 50% effort working with scientists from

Eligibility: All requirements for a doctorate should be completed by
September 1, 2001. Applicants must show evidence of mathematical
excellence, but they do not need to be a specialist in the field. The
following materials must be submitted (all materials should arrive by Jan.
15, 2001): (1) personal statement of scientific interest, research plans,
and reasons for wishing to participate in the Mathematics in the
Geosciences program or the Industrial Program (this is an essential part
of the application); (2) curriculum vitae and a list of publications; (3)
three letters of recommendation, to be sent directly to the IMA, (4) Submit
the Official IMA Application form located at
Senior memberships are also available. Preference will be given to
supplementary support for persons with sabbatical leaves, fellowships, or
other stipends.
Send to: Visiting Membership Committee, Institute for Mathematics and its
Applications, University of Minnesota, 400 Lind Hall, 207 Church St. SE,
Minneapolis, MN 55455-0436 U.S.A. The University of Minnesota is an Equal
Opportunity Educator and Employer.


From: Tim Kaiser <>
Date: Fri, 23 Jun 2000 09:25:08 -0700
Subject: Staff Position at San Diego Supercomputer Center

Posting Number: 021600-G
San Diego Supercomputer Center (SDSC)
Hiring Salary Range: $47,000-82,900/year
Filing Deadline: Open Until Filled

Review of resumes will begin on June 21, 2000 and will continue until
the position is filled.


Analyze, evaluate, and identify tools for enabling the efficient usage
of SDSC's supercomputers. Tools include debuggers, profilers, libraries,
and compilers. Present results in written documentation, informal
discussions, and training sessions, to provide advanced technical
guidance to others on an ongoing basis and be recognized as a resource
in the area of parallel tools and environments. Remain abreast of and
help advance the state-of-the-art in the area of tools for parallel
scientific programming on supercomputers through collaboration in proposals
and R&D with UCSD Computer Systems Engineering and other external
organizations. Work on multiple problems or tasks, not necessarily well
defined, and make recommendations that impact an entire project or system.


Bachelor's degree in Computer Science or a related scientific field
with relevant programming experience or a comparable combination of
education and experience. Demonstrated work experience with at least
one of the specified: key programming languages such as Fortran, C, or C++,
and application development environments relevant to high performance
computer programming and debugging. Advanced knowledge of parallel
application development and the application and development environments
relevant to supercomputing programming (Unix). Ability to perform studies
to determine requirements for parallel programming tools and applicability
of tools to particular projects. Excellent oral and written communication

For information about the SDSC, visit

EEO/AA Employer


For Recruitment Information and Selection Procedures, please refer to
the Manager's Workbench at


From: David Alexander <>
Date: Tue, 20 Jun 2000 09:26:08 -0500
Subject: Staff Position at Wichita State University

System Administrator/Trainer
High Performance Computing Center
Wichita State University

A full-time position responsible for system administration of the SGI
Origin 2000 computer in the High Performance Computing Center (HiPeCC) at
Wichita State University and for training faculty and students in effective
utilization of the machine is now available. For information and
application materials, go to This
position offers a competitive salary, excellent benefits, and an
opportunity to work with faculty in an intellectually stimulating
environment. Time for personal research is included in the job
description. The starting date is negotiable, but preferably by August 14,
2000. To ensure full consideration, applications must be received by July
10, 2000; the position will remain open until position filled. AA/EOE. For
information contact David Alexander at (316) 978-3988 or or FAX at (316) 978-3350.

Best regards,



From: Armin Iske <>
Date: Mon, 19 Jun 2000 13:41:34 +0200
Subject: Research Positions at the NetAGES Project

Four Ph.D. scholarships in; applied mathematics, computer vision, and
signal/image processing are available from a consortium comprising of:

GECO Research (SSR), Stavanger, Norway.
Munich University of Technology (TUM), Mathematics Department, Germany.
Stavanger University College (HiS), Dept. Electr. & Comp. Eng., Norway.
University of Vienna (UniVie), Mathematics Department, Austria.
The Ph.D. students will participate in the new European Union research
and training project
NetAGES (Network for Automated Geometry Extraction from Seismic)
The partners intend to provide cross-training of the young researchers
between industry and academia and across academic institutions.
The scientific objective is to develop new methodologies for updating
3D geometric descriptions based on measurement data and modelled
responses applied to petroleum reservoir life cycle monitoring using
seismic data. This is a problem area with a high research focus and
significant implication for the oil and gas industry. The highly
skilled multi-disciplinary team of SSR is a leading solution provider
in this area. The Ph.D. students' missions will be to develop new and
complementary competencies in automatic 3D geometry extraction and up-
and down-scaling technologies.

The NetAGES consortium is an equal opportunities employer, the positions
are open to all qualified European candidates without regard to race,
creed, sex or physical mobility. The Ph.D.'s are expected to start in
September 2000.

All positions are of three years duration. The students must expect a
high level of travel activities during the project, with the expenses
covered by the consortium. The salaries will be compatible with similar
positions at the respective institutions. Applications should be sent to
Schlumberger Stavanger Research, Attn: NetAGES, P.O. Box 330, 4002 Stavanger,
Norway, fax +47 51 50 65 00 or email to
Further information on the four Ph.D. positions may be obtained at or by contacting the partners:

Dr. Kjetil Fagervik, SSR (,
+47 51 50 63 35)
Dr. Trygve Randen SSR ( +47 51 50 64 19)
Dr. Armin Iske, TUM (, +49 89 289-28375)
Prof. Jan Erik =D8deg=E5rd, HiS (, +47 51 83 20 44)
Prof. Hans Georg Feichtinger, UniVie (,
+43-1-4277 50696)


From: SibJNM <>
Date: Wed, 21 Jun 2000 11:37:18 +0600
Subject: Contents, Siberian Journal of Numerical Mathematics

CONTENTS, Siberian Journal of Numerical Mathematics
Volume 3, No. 3 2000

For information to contributors and about subscriptions

A.S. Alekseev, B.G. Mikhailenko
Numerical-analytical algorithms of solution to the forward and
the inverse problems in seismology
(in English), pp.191-214

A.B. Andreev, T.D. Todorov
Lumped mass error estimates for an isoparametric finite element
eigenvalue problem
(in English), pp.215-228

P.W. Hemker, G.I. Shishkin, L.P. Shishkina
Distributing the numerical solution of parabolic singularly perturbed
problems with defect correction over independent processes
(in English), pp.229-258

I.V. Konnov
Properties of gap functions for mixed variational inequalities
(in English), pp.259-270

V.M. Kovenya
Splitting methods for the numerical
solution of multi-dimensional problems of gas dynamics
(in English), pp.271-280

V.A. Ogorodnikov, A.V. Protasov
Variational methods of data assimilation in the problem of stochastic
modelling of complexes of hydrometeorological fields
(in English), pp.281-294


From: Technical Group <>
Date: Tue, 20 Jun 2000 16:35:45 +0400 (MSD)
Subject: Contents, East-West Journal of Numerical Mathematics

Vol.8, No.2, 2000, pp.83-152


Discrete Sobolev and Poincare inequalities via Fourier series
S.C. Brenner and L.-Y. Sung

Mortar finite volume element approximations
of second order elliptic problems
R. Ewing, R. Lazarov, T. Lin, and Y. Lin

Mortar estimates independent of number of subdomains
J. Gopalakrishnan

Lax-Wendroff type second order evolution Galerkin
methods for multidimensional hyperbolic systems
M. Lukacova-Medvid'ova and G. Warnecke


From: Do Y. Kwak <>
Date: Sun, 25 Jun 2000 10:09:20 +0900
Subject: Contents, KSIAM Journal

Contents of KSIAM Journal Vol 4 No 1

Duality for nonsmooth multiobjective fractional programming with
V--invexity Hun Kuk 1-10

Parameter estimation problem for nonhysteretic infiltration in soil
Chung-Ki Cho, Sungkwon Kang and YongHoon Kwon 11 -22

On the security of certain hyperelliptic curves
Insuk Kim, SungTae Jun 23-28

A criterion on primitive roots modulo
Hwasin Park, Joongsoo Park and Daeyeoul kim 29-38

T-Fuzzy integrals of set-valued mappings
Sung Jin Cho 39-48

On the numerical inversion of the laplace transform by the use of an
optimized legendre polynomial Abdulaziz Al-Shuaibi 49-66

Error estimates and superconvergence for finite element
approximation for nonlinear parabolic problems Qian Li 67-78

Accuracy of iterative refinement of eigenvalue problems
Jolanta Gluchowska-Jastrzebska, Alicja Smoktunowicz 79-92

Issues of estimation in the monitoring of constant flow continuous
streams S. S. Dragomir 93-100

Further bounds for the estimation error variance of a continuous
stream with stationary variogram S. S. Dragomir 101-106

The existence theorem of orthogonal matrices with p nonzero entries
Gi-Sang Cheon, Sang-Gu Lee and Seok-Zun Song 107-118

A numerical analysis of czochralski single crystal growth of silicon
with misaligned cusp magnetic fields Chang Nyung Kim 119 -130

Some properties of mutual information and typical set
Young Soo Lee 131-142


End of NA Digest