NA Digest Sunday, July 31, 1994 Volume 94 : Issue 31

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

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From: NA Digest <>
Date: July 31, 1994, 14:00 MDT
Subject: NA Digest Calendar

NA Digest Calendar
Date Topic Place NA Digest #

Aug. 1- 4 Computation Physics Lyngby, Denmark 11
Aug. 1- 5 Computational Science Workshop Los Alamos, NM 16
Aug. 10 Sparse Matrices Lyngby, Denmark 29
Aug. 15-19 Math Programming Ann Arbor, MI
Aug. 21-26 Numerical Methods Sofia, Bulgaria 30
Aug. 22-25 Continuum Mechanics Prague, Czech Rep. 6
Aug. 22-25 SVD and Signal Processing Leuven, Belgium 23
Aug. 22-25 Simulation Zurich, Switzerland 9
Aug. 29-31 Algorithms and Parallel VLSI Leuven, Belgium 23
Aug. 29... Mathematical Modelling Prague, Czech Rep. 1

Sep. 6-10 Mathematics in Industry Kaiserslatern, Germany 7
Sep. 12 Scottish Computational Mathematics Strathclyde, Scotland 23
Sep. 22-24 Hellenic Mathematical Society Athens, Greece 8
Sep. 25-30 Computers and Mathematics Harare, Zimbabwe 28
Sep. 26-27 Acoustics and Electromagnetics Washington, DC 19
Sep. 26-28 Multilevel Methods Meisdorf, Germany 16
Sep. 26-28 Large-Scale CFD Problems Montreal, Canada 24
Sep. 26-30 Total Positivity Jaca, Spain 5
Sep. 26 Dynamics of Discontinuous Systems Bristol, UK 20
Sep. 30... Algorithms for Macromolecular Modeling Lawrence, KA 28

Oct. 2- 6 Applications of Operator Theory Winnipeg, Manitoba 17
Oct. 6- 7 Combustion, Environment, and Heating Columbus, Ohio 21
Oct. 6- 7 Large Systems of Equations Wuppertal, Germany 23
Oct. 9-11 European PVM Users Rome, Italy 30
Oct. 12-14 Scalable Parallel Libraries Mississippi State, MS 24
Oct. 13-14 60th birthday of Jean Descloux Lausanne, Switzerland 19
Oct. 17-20 Parallel Computational Fluid Dynamics Stuttgart, Germany 30
Oct. 18-21 High Performance Fortran Manno, Switzerland 24
Oct. 20-22 Systems, Control, Information Wuhan, China 8
Oct. 22 Pacific Northwest N.A. Seminar Pullman, WA 31
Oct. 24-26 Computational Molecular Dynamics Minneapolis, MN 19
Oct. 26-28 Singularities in PDEs Bristol, UK 26

Nov. 7- 9 Adaptive Grid Methods Hampton, VA 26
Nov. 12 Matrix Theory Salt Lake City, UT 21
Nov. 18 Parallell Computing Applications Utrecht, Nethelands 24
Nov. 14-18 SuperComputing '94 Washington, DC 6
Nov. 30... Computational Methods in Engineering Belo Horizonte, Brazil 11

Dec. 16-19 Methods and Applications of Analysis Hong Kong 25


Jan 3- 6 Computational Computer Design Maui, Hawaii 17
Jan. 9-10 Conference Honoring Ake Bjorck Linkoping, Sweden 26
Jan. 15-18 Bond Graph Modeling and Simulation Las Vegas, NV 4
Jan. 16-18 Markov Chains Raleigh, NC 7
Jan. 23-27 Optimal Design and Control Newport News, VA 31

Feb. 6- 9 Massively Parallel Computation McLean, VA 26
Feb. 8-10 Computational Issues in the Geosciences San Antonio, TX 27
Feb. 15-17 SIAM Conference on Parallel Processing San Francisco, CA
Feb. 19-25 Applications of Interval Computations El Paso, TX 16

Mar. 17-18 Krylov Subspace Methods Raleigh, NC 29
Mar. 20-21 Nonconvex Energy Functions Rutgers, NJ 20
Mar. 28... Sci. Computation & Diff. Eqns. Stanford, CA 27

Apr. 2- 7 Multigrid Methods Copper Mountain, CO 30
Apr. 3- 6 Numerical Methods for Fluid Dynamics Oxford, UK 25
Apr. 24-28 3rd INRIA-SIAM Wave Propagation Conf. Juan-les-Pins, France 19
Apr. 26-30 Numerical Analysis & Applied Math. Constanza,Romania 26

June 6-10 Inertial Manifolds Xi'an, China 21
June 18-21 Iterative Methods in Linear Albebra Blagoevgrad, Bulgaria 30
June 20-24 Honoring G. I. Marchuk Novosibirsk, Russia 28

July 3- 7 ICIAM, Int'l Cong. Indust. Appl. Math. Hamburg, Germany 23
July 10-12 Linear Algebra and Applications Manchester, UK 19
July 16... Mathematics of Numerical Analysis Park City, UT 5
July 17-21 Distributed Parameter Systems Warsaw, Poland 25

Aug. 27-31 Circuit Theory and Design Istanbul, Turkey 25
Sep. 17-21 Acoustics of Submerged Structures Boston, MA 22


From: Arnold Neumaier <>
Date: Mon, 25 Jul 94 09:30 EDT
Subject: Variational Principles and Convexity Check

1. Has anyone seen any work related to the following `local' variational

Find x such that z=x is a local minimizer of f(x,z),
where f(x,z) is C^2 and bounded below for each fixed x.

Many dissipative problems have a presentation in the above form,
e.g., fluid dynamics equations (P. Glansdorff and I. Prigogine,
Thermodynamic theory of structure, stability and fluctuations,
Wiley 1971, Chapter 10).

Using the optimality conditions one can rephrase the problem to
get the nearly equivalent problem

Find x such that f_z(x,x)=0 and f_{zz}(x,x) is positive semidefinite.

It would be interesting to have numerical methods that do not require
explicit second derivative information but can approximate it in a
quasi-Newton manner.

2. Given m data points (x_i,f_i) in R^n x R, are there necessary and
sufficient conditions that there is a convex function f with
f(x_i)=f_i for i=1,...,m? (For n=1, it suffices to check that the
second divided differences of adjacent triples of points are

Arnold Neumaier (until August 26, 1994) (after September 1, 1994)


From: Rob MacLeod <>
Date: Mon, 25 Jul 94 13:59:29 -0600
Subject: 3D Navigation Problem

"Everyone" knows that to find a point in 3-space, the distances from three
known points to the desired point are all that is required (as long as the
desired point does not lie in the plane of the other three). Where we are
stuck is solving the resulting (nonlinear) system of equations in some sort
of efficient manner.

The application is reconstructing torso geometries in experimental
cardiology (read "We are not mathematicians"), but the problem is clearly
much more general, for example in navigation. Hence, there have to be some
reasonable solutions out there.

Thanks in advance for any tips.

Rob MacLeod
Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI)
Building 500, University of Utah
Salt Lake City, Utah 84112
Phonemail: (801)581-8183
Fax: (801)581-3128


From: T. J. Garratt <>
Date: Thu, 28 Jul 1994 19:33:43 GMT
Subject: X-window Sparse Matrix Viewer

Wanted: X-window sparse matrix viewer

I'm sure one of these must be about someplace, but I'm looking for a program
that can be used to view sparse matrices of variable order using the X
protocol. That is, you give the program a non-zero sparsity pattern and an X
window pops up graphically showing the sparsity pattern with, say, a pixtel
for each non-zero.

Sounds nice... perhaps someone has produced one in their spare time.
Any hints of where to fine such a code would be most welcome.

Tony Garratt


From: John Prentice <>
Date: Thu, 28 Jul 94 16:27:07 MDT
Subject: Questions about Electromagnetic Diffractive Tomography

I am designing an electromagnetic diffractive tomography system for use
in conjunction with a ground penetrating radar experiment. One of the
books I have been reading to come up to speed on this subject is "Principles
of Computerized Tomographic Imaging" by Kak and Slaney, published
in 1988 by IEEE. So, first question, does anyone have a recommendation
for better books to look at? Next, the authors of this book make two
interesting claims. The first is that a vector theory for diffractive
tomography had not yet been developed as of when they wrote their book.
By a vector theory, they mean a theory that is based on the vector
wave propagation equation for an electromagnetic field in a nonlinear
dielectric medium. Everything they do is using a scalar wave equation.
I am curious if this is still true, does anyone know of a diffraction
tomography theory that is based on the full vector wave equation?
My next question, these authors also comment that diffractive
tomography based on a higher order Born series is a subject of current
research. I am anxious to find out what has been done on this since
their book was written. Is anyone familiar with diffractive tomography
that is not based on the 1st order Born approxiation or the first order
Rytov approximation? A final related question, is anyone familiar
with a diffractive scattering/tomography theory that is posed in terms
of modern operator theory, analogous to quantum scattering theories
based on the operator form of the Lippman-Schwinger equation for the
transition and scattering operators?

I appreciate the help!


John K. Prentice
Quetzal Computational Associates
3701 San Mateo N.E., Suite I, Albuquerque, NM 87110-1249 USA
Phone: 505-883-3706 E-mail: or


From: J. C. Diaz <>
Date: Wed, 27 Jul 94 08:49:17 CDT
Subject: Temporary Address Change for J. C. Diaz

Temporary address change for J. C. Diaz while on Sabbatical in
Spain from July 21, 1994 through January 5, 1995.

The business address will be:
Profesor J. C. Diaz
Departamento de Matematica Aplicada y Computacion
Facultad de Ciencias
Universidad de Valladolid
Cl. Prado de la Magdalena S/N
Fax 011-(34)-83-42-3013 (Must state Dept name completely)
Tel 42-3181 (office)
30-6856 (home)

The email will remain

Home address:
Cl. Canovas del Castillo 11, 3-H
47002 - Valladolid


From: George Byrne <>
Date: Wed, 27 Jul 1994 11:45:50 -0500 (CDT)
Subject: Change of Address for George Byrne

George D. Byrne was recently appointed Professor and Chairman, Department of
Mathematics, Illinois Institute of Technology, 10 West 32nd Street,
Chicago, Il 60616-3793. e-mail:


From: Andrei Knyazev <knyazev@WIDLUND.CS.NYU.EDU>
Date: Sat, 30 Jul 94 15:25:59 -0400
Subject: Change of Address for Andrew Knyazev

Andrew Knyazev, formerly a senior researcher at the Institute
of Numerical Mathematics Russian Academy of Science, Moscow, and then
a visitor at the Courant Institute of Mathematical Science, NYU,
has accepted a position as an associate professor in the Departament
of Mathematics at the University of Colorado at Denver.


From: Eduardo Sontag <>
Date: Tue, 26 Jul 94 17:04:25 BST
Subject: Phone Numbers at Rutgers


Around Sept 1, 1994, the three-digit prefix for the telephone numbers of
individuals, as well as administrative offices, at several Rutgers departments
(in the New Brunswick-Piscataway campus), including among others:


will change, from "932" to "445". The actual numbers (last 4 digits) will
remain the same. Thus the change is given by the following rule:

+1 908.932.abcd --> +1 908.445.abcd

Please take note.


From: Steve Stevenson <>
Date: Tue, 26 Jul 94 11:39:21 EDT
Subject: Computational Science and Engineering WWW Node at Clemson

Clemson University CSE Program (joint mathematical science-computer science)
has a WWW node at

This node is oriented towards undergraduate and graduate education. There
are pointers to many of the educational programs around the world, as well
as course materials and software.

We have tried to keep up with the notices that come across the net. If
we've missed you and you want to provide a URL, please contact

Steve Stevenson
Computer Science


From: Natalia Alexandrov <>
Date: Wed, 27 Jul 1994 11:25:29 -0400
Subject: ICASE/LaRC Course: Optimal Design & Control

January 23-27, 1995
OMNI Hotel, Newport News, Virginia

We are pleased to announce that the Institute for Computer Applications
in Science and Engineering (ICASE) and NASA Langley Research Center
(LaRC) will conduct a Short Course on Optimal Design and Control at the
OMNI Hotel, Newport News, Virginia from January 23-27, 1995.

The course is intended primarily for scientists and engineers as an
overview of the state-of-the-art in the theory and practice of
optimization-based design and control. On the theoretical side, there is
now a general framework that allows for a unified treatment of optimal
nonlinear control, linear feedback control, robust control, and optimal
design for both lumped and distributed parameter systems. At the
same time, there have been tremendous breakthroughs in the development
of computational methods for design and control. The goal of this short
course is to present an overview of these new results and to provide
engineers and control scientists with practical working knowledge of these
new theories and computational tools. Special attention will be paid to
applications in order to illustrate, by examples, the use of theoretical
and computational ideas presented in the lectures.

There will be four one-and-one-half hour lectures a day. The week-long
course is intended to provide a total of approximately 30 hours of
lectures. Course notes will be provided to all participants in order to
facilitate discussion during the lecture periods. The lecturers and
course topics are as follows:

John Burns, Virginia Polytechnic Institute and State University
Optimal Design (open loop distributed parameter
optimal control; shape optimization with applications
to fluids; inverse problems and parameter estimation)

H. Thomas Banks, North Carolina State University
Linear Feedback Control (linear quadratic regulator
(LQR) and Kalman filter; min-max control; tracking
problems and disturbance attenuation with applications
to structures and acoustics)

Ruth Curtain, University of Groningen, The Netherlands
Robust Control (H* control design; finite dimensional
compensators for infinite dimensional systems; robust
stabilization of infinite-dimensional systems with
respect to coprime factor perturbations)

Christopher Byrnes, Washington University, St. Louis, Missouri
Nonlinear Control (nonlinear control of distributed
parameters systems; optimal feedback control; Riccati
partial differential equations)

Alan Laub, University of California, Santa Barbara
Computational Control (stability and conditioning of
numerical algorithms for control design; numerical
solution of coupled Riccati equations)

Due to space considerations, attendance will be limited. There will be a
registration fee which is still undecided. If you wish to attend or
would like further information, please get in touch with
Natalia Alexandrov
ICASE, Mail Stop 132C
NASA Langley Research Center
Hampton, VA 23681-0001
Tel. 804-864-7059
FAX: 804-864-6134


From: Alan Genz <>
Date: Thu, 28 Jul 94 16:25:20 -0700
Subject: Pacific Northwest Numerical Analysis Seminar

October 22, 1994
Department of Mathematics
Washington State University
Pullman, Washington 99164-3113

Alan Genz,
Kevin Cooper,
V.S. Manoranjan,

The annual PNWNAS will be held this year on Saturday, October 22, at
Washington State University. The purpose of this conference is to bring
together research workers in Numerical Analysis from companies and
universities in the Pacific Northwest, to meet and discuss recent work.
The format this year will consist of some invited talks, several
contributed talks and a poster session. If you would like to present a
contributed talk or poster, please send a title and short abstract by
September 25 to Alan Genz. We encourage contributions from graduate
students. We plan to have a special graduate student presentation. If you
are a graduate student who would like to be considered for this, please
send a title and 2-3 page extended abstract to Alan Genz by September 25.
There will not be a registration fee, but a conference buffet dinner will
be organized, and there will be a charge of $15 per person.

Please contact me via email before Oct. 14 for an electronic registration
form. And, please forward this announcement to graduate students and

Alan Genz,


From: Marilyn Radcliff <>
Date: Mon, 25 Jul 1994 15:45:02 -0400 (EDT)
Subject: Contents, J. of Approximation Theory

Table of Contents
Journal of Approximation Theory, Volume 77, Number 3, June 1994

A. L. Levin and D. S. Lubinsky. $L_p$ Markov-Bernstein Inequalities for
Freud Weights, 229-248.

M. W. Bartelt and J. J. Swetits. Characterization of the Local Lipschitz
Constant, 249-265.

Li Chong and G. A. Watson. On Approximation Using a Peak Norm, 266-275.

Eduard Danielian and Karen Tatalian. Sign-Change Diminishing Systems of
Functions of Many Variables, 276-281.

Paul Nevai and Yuan Xu. Mean Convergence of Hermite Interpolation, 282-304.

H. G. Meijer. Sobolev Orthogonal Polynomials with a Small Number of Real
Zeros, 305-313.

Aleksei Shadrin. On $L_p$-Boundedness of the $L_2$-Projector onto Splines,


From: Grant Guevremont <grantg@CERCA.UMontreal.CA>
Date: Thu, 28 Jul 1994 12:44:04 -0400
Subject: Contents, I. J. Computational Fluid Dynamics

Vol. 2, No. 2, 1994

Single Stage Rocket Performance Prediction and Test
T. P. Gielda, T. M. Walter and R. K. Agarwal

Covolume-Dual Variable Method for Thermally Expandable
Flow on Unstructured Triangular Grids
C. A. Hall, T. A. Porsching and P. Hu

A Direct Numerical Simulation of Channel Flow Transition
Under an External Body Force
C. C. Hao and J. N. Chung

Development of a Reynolds Stress Model With a Cross
Diffusion of k in the 'epsilon' Equation
R. R. Hwang and Y. F. Peng


End of NA Digest