NA Digest Monday, May 30, 1994 Volume 94 : Issue 22

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

Submissions for NA Digest:

Mail to

Information about NA-NET:

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From: NA Digest <>
Date: Mon May 30 18:42:17 EDT 1994
Subject: Calendar

Calendar of Forthcoming Events
Date Topic Place NA Digest #

June 2- 3 Computational Fluid Dynamics Toronto, Canada 2
June 6- 8 Supercomputing Symposium '94 Toronto, Canada 2
June 6-10 Applied and Industrial Mathematics Linkoping, Sweden 14
June 6-14 Mathematics Modeling Workshop Claremont, CA 9
June 11-15 Continuous Algorithms and Complexity Mount Holyoke, MA 13
June 13-17 Hyperbolic Problems Stony Brook, NY 19
June 15-18 SIAM Applied Linear Algebra Snowbird, UT 17
June 20-23 Parallel Scientific Computing Lyngby, Denmark 18
June 22-25 SIAM Conference on Discrete Mathematics Albuquerque, NM
June 23-25 Monte Carlo Methods Las Vegas, NV 18
June 27-28 5th Stockholm Optimization Days Stockholm, Sweden 6

July 4- 6 South African Numerical Mathematics Umhlanga Rocks, Natal 18
July 5- 7 Simulation of Devices and Technologies Obninsk, Russia 7
July 11-15 IMACS World Congress Atlanta, GA
July 11-15 Course on MODULEF Finite Elt. Library University Park, PA 12
July 18-29 SERC Numerical Analysis Summer School Leicester, UK 16
July 18-30 Summer Short Courses in CFD Istanbul, Turkey 15
July 22-23 Control Problems in Industry San Diego, CA 3
July 23 SIAM Forum San Diego, CA 20
July 24 AWM Workshop for Pre- and Post-docs San Diego, CA 3
July 25-29 SIAM Annual Meeting San Diego, CA 3

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

Sep. 6-10 Mathematics in Industry Kaiserslatern, Germany 7
Sep. 22-24 Hellenic Mathematical Society Athens, Greece 8
Sep. 26-27 Acoustics and Electromagnetics Washington, DC 19
Sep. 26-28 Multilevel Methods Meisdorf, Germany 16
Sep. 26-30 Total Positivity Jaca, Spain 5
Sep. 26 Dynamics of Discontinuous Systems Bristol, UK 20

Oct. 2- 6 Applications of Operator Theory Winnipeg, Manitoba 17
Oct. 6- 7 Combustion, Environment, and Heating Columbus, Ohio 21
Oct. 20-22 Systems, Control, Information Wuhan, China 8
Oct. 13-14 60th birthday of Jean Descloux Lausanne, Switzerland 19
Oct. 24-26 Computational Molecular Dynamics Minneapolis, MN 19

Nov. 12 Matrix Theory Salt Lake City, UT 21
Nov. 14-18 SuperComputing '94 Washington, DC 6
Nov. 30... Computational Methods in Engineering Belo Horizonte, Brazil 11


Jan 3- 6 Computational Computer Design Maui, Hawaii 17
Jan. 9-10 Conference Honoring Ake Bjorck Linkoping, Sweden 14
Jan. 15-18 Bond Graph Modeling and Simulation Las Vegas, NV 4
Jan. 16-18 Markov Chains Raleigh, NC 7

Feb. 15-17 SIAM Conference on Parallel Processing San Francisco, CA
Feb. 19-25 Applications of Interval Computations El Paso, TX 16

Mar. 20-21 Nonconvex Energy Functions Rutgers, NJ 20

Apr. 24-28 3rd INRIA-SIAM Wave Propagation Conf. Juan-les-Pins, France 19

June 6-10 Inertial manifolds Xi'an, China 21

July 3- 7 ICIAM, Int'l Cong. Indust. Appl. Math. Hamburg, Germany 9
July 10-12 Linear Algebra and Applications Manchester, UK 19
July 16... Mathematics of Numerical Analysis Park City, UT 5


From: Atanu Basu <>
Date: Sun, 22 May 1994 14:53:30 -0500
Subject: Chemical Engineer Seeking Position.

Dear Reader:

I am a Chemical Engineer (M.S.) with background in Mathematical Modeling,
Process Simulation, and Numerical Analysis. I would sincerely appreciate
if anybody can give any leads/suggestions/recommendations about a suitable
position for me. I will NOT be available through email anymore. I hope
that the responders of the above request will be kind enough to reach me
at the following address and phone #.

Thank you very much for your consideration and time.


Atanu Basu
130 New Road (#A7)
Parsippany, NJ 07054
(201) 575-0094


From: Scott Mitchell <>
Date: Mon, 23 May 94 10:50:48 MDT
Subject: Seeking Position in Unstructured Mesh Generation

I am looking for a position in unstructured mesh generation.
My research papers describe algorithms for generating/refining
two and three dimensional meshes of arbitrary regions
with provable bounds on the number of elements and element shape.
Of particular interest is an innovative disk packing technique
which yields a non-obtuse triangulation.

I have also worked on a couple of projects writing practical mesh
generation code (in C++), and proof of concept programs (in Matlab).

Thank you,

Scott A. Mitchell, Ph.D.
Sandia Nat'l Labs


From: Rabi H. Mohtar <>
Date: Wed, 25 May 94 15:11 EDT
Subject: Stability of Non-linear Systems

Dear na-neters:
I am working on a non-linear 2-D 2-phase flow problem. The system's stability
is dependent on many variables: pressure, material properties, mesh geometry,
to name a few. I would like to understand and define the regions where the
problem is stable. Can anyone guide me as to a criteria or a measure for the
syste m stability?

Thank you for your help. Please send information to me at:

Rabi Mohtar
Agricultural and Biological Engineering


From: Stanly Steinberg <>
Date: Wed, 25 May 94 19:09:09-030
Subject: Hyperbolic Conservaton Laws with Source Terms

We are trying to solve numerically two different systems of hyperbolic
conservation laws with source terms, one that describes traffic flow and
another is a flow in porous media (flow with resistance) problem. The source
terms make the system mildly diffusive. We are concerned that the diffusion in
many numerical schemes will overwhelm the natural diffusion of the system.
Also, there are a number of interesting cases where the density is zero in part
of the region and thus the PDEs are singular. In addition, the density for the
porous media problem is an approximate solution of the simpler scalar porous
media equation
u_t = Laplacian(u^m)
with m > 1. We are considering using some front-tracking with moving grids
algorithms for this case.

We are looking for additional recent reference to numerical or analytic work on
such problem. Any assistance will be appreciated.
Stan Steinberg, Department of Mathematics and Statistics,
University of New Mexico, Albuquerque NM 87131 USA.
Paulo Zingano, Departamento de Matematica Pura e Aplicada
Instituto de Matematica
Universidade Federal do Rio Grande do Sul
Av. Bento Goncalves, 9500
91509-900 Porto Alegre, RS, Brazil


From: Leon Prucha <>
Date: Fri, 27 May 1994 12:29:04 +1000 (EST)
Subject: Is NPSOL Available in C?

I am trying to find out if I can get a copy of the source code for
"NPSOL", a nonlinear programming package developed by the systems
optimization laboratory at stanford university. In addition I would also
like to know if this software is available written in "C" programming

Now if there is any information on getting a copy of the software could it
be E-mailed to me < >. This information would be
greatly appreciated.


From: Dieter Kraft <>
Date: May 23, 1994, 18:38:26
Subject: New Book, Computational Optimal Control

Birkhauser Publishers announce Volume 115 of
International Series of Numerical Mathematics (ISNM)
K.-H. Hoffmann, H. D. Mittelmann, and J. Todd (editors)

'Computational Optimal Control'
R. Bulirsch and D. Kraft (eds.)
Birkhaeuser, Basel, Boston, Berlin, 1994
ISBN 3-7643-5015-6
ISBN 0-8176-5015-6

Table of Contents:
1 A Survey on Computational Optimal Control
2 Theoretical Aspects of Optimal Control and Nonlinear Programming
3 Algorithms for Optimal Control Calculations
4 Software for Optimal Control Calculations
5 Applications of Optimal Control

Summary from the Preface:
.... These proceedings contain selected papers from an 'IFAC Workshop on
Control Applications of Optimization', which took place at the Fachhochschule
Muenchen in September 1992. The workshop was attended by ninety researchers
from four continents. This volume represents the state of the art in the field,
with emphasis on progress made since the publication of the proceedings of the
Capri meeting. ....

For more information use FTP of file Comp-Opt-Contr
in directory /pub/comp/math/matlab

Dieter Kraft <>


From: Venkataramanan Balakrishnan <>
Date: Thu, 26 May 1994 08:56:43 -0700
Subject: New Book, Linear Matrix Inequalities


(Volume 15 of SIAM Studies in Applied Mathematics)

Stephen Boyd, Laurent El Ghaoui, Eric Feron and
Venkataramanan Balakrishnan

Available June 1994 / Approx 220 pages / Hardcover
ISBN 0-89871-334-X

List Price $36.50 / SIAM Member Price $29.20
All royalties donated to a fund to help students attend
SIAM conferences

To Order: Call 1-800-447-SIAM Order Code AM15
(outside the USA, call 215-382-9800)
Via email:

The authors reduce a wide variety of problems from Systems
and Control Theory to a handful of standard convex and
quasiconvex optimization problems that involve linear matrix
inequalities. These standard problems can be solved very
efficiently using recently developed numerical algorithms;
therefore the reduction constitutes a solution to the
original problems.


Chapter 1: Introduction.
Chapter 2: Some Standard Problems Involving LMIs.
Chapter 3: Some Matrix Problems.
Chapter 4: Linear Differential Inclusions.
Chapter 5: Analysis of LDIs: State Properties.
Chapter 6: Analysis of LDIs: Input/Output Properties.
Chapter 7: State-Feedback Synthesis for LDIs.
Chapter 8: Lur'e-Postnikov and Multiplier Methods.
Chapter 9: Bounds for Systems with Multiplicative Noise.
Chapter 10: Miscellaneous Problems.
List of Acronyms

The file (available via anonymous ftp into in pub/boyd/lmibook) contains the complete table
of contents and the first two chapters. It should give some idea
of the book.


From: Jonathan Shewchuk <>
Date: Sat, 28 May 94 21:27:55 -0400
Subject: Erratum for "An Intro to CG Without the Agonizing Pain"

In early April, I advertised in NA Digest my Technical Report "An
Introduction to the Conjugate Gradient Method Without the Agonizing
Pain". Since then, the Internet has worked its magic and helped me
to find all sorts of errors in the text.

If you have a copy of the original report, please take a few moments
to obtain the Erratum. It is available by anonymous FTP to
REPORTS.ADM.CS.CMU.EDU (IP address under the filename
1994/CMU-CS-94-125.errat . The Erratum is a short ASCII file. In
addition, I will soon make available a corrected version of the report,
which I will announce when it is ready.

The article itself is also still available from the above FTP site,
but I recommend waiting a few weeks until the corrected version is

Many thanks to all of you who took the time to send in their comments
and corrections. You have been very helpful in refining the final

Jonathan Shewchuk

P.S. I'm still looking for an intuitive geometric explanation for why
most of the "beta" terms in CG become zero, thus making it possible
to generate the direction vectors with coupled recurrences. If anybody
has any suggestions, please let me know.


From: Larry Lambe <>
Date: Tue, 24 May 94 16:01:21 EDT
Subject: Workshop on Symbolic Computational Mathematics

A Workshop on New Technology
Symbolic Computational Mathematics
Applications in Research and Education

Larry Lambe Dick Peskin
CAIP Center, CoRE Bldg.
Rutgers University
June 6 to June 10, 1994

Object oriented methods, properly used, can eliminate many of the
bottlenecks in syntactical debugging (i.e. the detection and
correction of "typos" and similar mistakes made in writing software).
They can also reduce time spent on logical debugging by providing a
mathematically precise foundation for object code and the ability to
write efficient algorithms for all objects of a given class using only
one implementation for all members of the class. This helps in the
conceptual design of complicated projects and also helps to keep the
amount of necessary code at a minimum. This Workshop is intended to
open up a discussion on the use of such techniques as applied to
mathematical software and also adddresses the best ways for providing
training in their use. The emphasis will be on object-oriented
symbolic computer mathematics and its applications in science and

One of the major features of modern mathematics is the systematic
hierarchical organization of its contents. Through this organization,
great strides have been made in communicating mathematical techniques
to a variety of audiences. We are experiencing the widespread
emergence of an analogous hierarchical organization in other areas such
as software systems, including operating systems. For example, the
AXIOM (formerly called Scratchpad) system was designed in a
mathematically object oriented way, taking advantage of many years of
expert software engineering and mathematical experience. It is fully
extendible by any user with the right training, and it may be
dynamically altered to behave in user specified ways.

An A# (C, Lisp or standalone executable code generator for Axiom
algorithms) tutorial will be included in the Workshop and the latest
version of the AXIOM system and A# compiler will be available for use
by participants during the Workshop.

All talks will be in the auditorium, first floor CoRE Bldg (beginning
at 10:00 and Monday and at 9:00 on Tuesday through Friday). The labs
will be in 637 CoRE in the late afternoon on Monday and Tuesday.

Contributed papers will be reviewed for inclusion in a special issue
of the Journal of Symbolic Computation on Symbolic Computation and

Registration in advance is required.

For more information contact Larry Lambe (
or Dick Peskin (

This Workshop is sponsered by IBM Corp., NAG, Inc., NSF, and the
Rutgers Univ. CAIP Center.


From: Rob Corless <>
Date: Tue, 24 May 1994 16:18:53 -0400
Subject: A# Course announcement


A# Programming Language Workshop
Day before ISSAC '94: 19 July 1994
St. Catherine's College, Oxford UK


A# is a programming language which allows symbolic and numeric
computations to be performed efficiently together.

Version 2 of the AXIOM computer algebra system provides an optimizing compiler
for A# as a separable component, as well as an intermediate code interpreter
and a library of data structures and mathematical abstractions.

The A# compiler can produce stand-alone executable programs, object libraries,
native operating system formats, portable byte code libraries, and C and Lisp
source code.

The A# programming language has support for object-oriented and
functional programming styles. Both types and functions are first
class values that can be manipulated with a range of flexible and
composable primitives and user programs. The A# language design
places particular emphasis on optimization and compilation for
efficient machine code, and portability. Trial ports have been
made to various:
> architectures (16-, 32-, and 64-bit), e.g. RS/6000, Sparc,
Alpha, i386, i286, M680x0, S 370;
> operating systems, e.g. Linux, AIX, SunOS, HP/UX, Next Mach,
and other Unix derivatives, OS/2, DOS/Windows, VMS, and CMS;
> C compilers, e.g. Xlc, Gcc, Sun, Borland, Metaware, and MIPS C.


The A# Programming Workshop, held Tuesday, July 19, one day
immediately preceeding ISSAC '94, will provide participants
with hands-on experience programming in A#. The programming workshop
will be presented by the developers of A#, and will cover topics including:
> The A# Programming Language
> Programming with types and functions as first class objects
> Developing stand-alone C and LISP applications
> Developing libraries for use by other C and Lisp programs
> Using A# to extend the Axiom Library


NAG (which markets AXIOM and A#) is a not-for-profit organization.
A fee is being charged for registration to help defray the cost of
holding the course.

Registration is US $100, discounted to US $50 for students.
The registration fee includes a trial-period copy of the A# software
and documentation, a buffet lunch, and coffee/tea service.
Participants are encouraged to BYONC (Bring Your Own Notebook Computer).
If you do, you will need at least 4M RAM + 20M free disk space
(6-8M + 30M would be better), and DOS 5.0 or higher---or---Linux.


For registration or additional information on the
A# Programming Language Workshop,
please contact:

Sandy Wityak
IBM T.J. Watson Research Center
P.O. Box 218; Yorktown Heights, NY 10598 USA
phone: +1 914-945-1187

AXIOM is a registered trade mark of NAG, Ltd.


From: Panayot Vassilevski <>
Date: Wed, 25 May 94 11:21:11 BG
Subject: IMACS Iterative Linear Algebra Symposium

Information about First Call for Papers

June 11-14, 1995, Blagoevgrad, Bulgaria

Organized by:
The International Association for Mathematics and Computers in Simulation
The Center of Informatics and Computer Technology at Bulgarian Academy
of Sciences (BAS)

Local Organizing Committee

Svetozar D. Margenov and Panayot S. Vassilevski
Center of Informatics and Computer Technology at BAS (Bulgarian
Academy of Sciences), Sofia, Bulgaria


The purpose of the Symposium is to provide a forum for the presentation
and the discussion of the recent advances in the analysis and
implementation of iterative methods for solving large linear systems
of equations and for determining
eigenvalues, eigenvectors or singular values of large matrices.


Matrix analysis
Convergence acceleration, preconditioning techniques,
methods for nonsymmetric, indefinite, singular and overdetermined systems,
sparse eigenproblems.

To partial differential equations (multigrid methods,
domain decomposition methods, spectral methods), to systems theory, to
least squares problems, to parallel matrix computation

Software development:
Sparse linear systems, sparse eigenproblems, application
oriented software; on sequential machines; on parallel machines.

General Information

The symposium will be held during June 11 -- June 14, 1995
The symposium will take place at Blagoevgrad,
The symposium language will be English.
The registration fee will be equivalent to US $ 300.
(to be spoecified later on in more detail what this fee will cover)

Special Sessions:

"The influence of high non--normality on the reliability of iterative methods
in Computational Linear Algebra", organized by Prof. Francoise
Chaitin-Chatelin, University of Paris and Dr. Valerie Fraysse, CERFACS, Toulouse

"Krylov--subspace methods for nonsymmetric and indefinite linear systems",
by Roland Freund, AT & T Bell Lab., Murray Hill, USA

"Iterative Monte Carlo methods", by Ivan T. Dimov, CICT, BAS, Sofia


Conference address:

Panayot S. Vassilevski
IMACS International Symposium
Center of Informatics and Computer Technology
Bulgarian Academy of Sciences
''Acad. G. Bontchev`` street, block 25A
1113 Sofia, Bulgaria

E-mail : imacs95@bgearn.bitnet


From: Najib Abboud <>
Date: Fri, 27 May 1994 11:44:20 -0400
Subject: Acoustics of Submerged Structures & Transduction Systems

Call for Papers
Symposium on
ASME 15th Biennial Conference on Mechanical Vibration and Noise
In celebration of
50th Anniversary of the ASME Design Engineering Division
held at
Boston Sheridan Hotel and attached Hynes Conference Center, Boston, MA
September 17-21, 1995

The purpose of this symposium is to provide a forum for basic and applied
researchers as well as design engineers to discuss state-of-the-art advances in
theoretical, computational, experimental and materials aspects of noise,
vibration and design of submerged structures and transduction systems. Enhancing
the information flow between theoreticians and engineers, facilitating the
technology transfer between government-sponsored research and industrial
development, and encouraging interdisciplinary cross-fertilization are all vital
functions of this symposium.

* Theoretical and computational aspects in the acoustic analysis of submerged
structures and transducers: analytical methods, asymptotic methods, ray
methods, spectral methods, FEM, BEM, adaptive methods, multigrid methods,
wavelets, fuzzy structures, probabilistic methods, radiation boundary
conditions, infinite elements...
* Scattering, propagation and radiation.
* Modeling of internal structures, substructuring, complexities, multi-scale
* Experimental studies, comparison with analysis.
* New materials, coatings or material models for submerged structures and

Abstract: November 15, 1994
Manuscript (4 copies): January 1, 1995
Notification of Acceptance: April 1, 1995
Final Manuscript on Mats: April 20, 1995

Papers will appear in reviewed archival ASME symposium proceedings. Authors
should submit abstracts to one of the symposium organizers:

Raymond P. Daddazio, Mohammed M. Ettouney, Najib N. Abboud

Address: Weidlinger Associates Inc.
Applied Science Division
333 Seventh Avenue
New York, NY 10001, USA
Tel: (212) 563-5200
Fax: (212) 695-4186

or send email to:


From: John Van Rosendale <>
Date: Fri, 27 May 1994 15:27:07 -0400
Subject: ICASE Multigrid Short Course

August 29 - September 2, 1994
Radisson Hotel, Hampton, 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 Multigrid Methods at the Radisson
Hotel, Hampton, Virginia from August 29 to September 2, 1994.

The course is intended primarily for scientists and engineers with elem-
entary knowledge of finite difference, finite volume, and finite element
methods for partial differential equations, as well as iterative
techniques. The key element of the course will be a cohesive development
of multigrid procedures for various problems of practical interest, with
an emphasis on analysis tools for performance prediction.

There will be four one-and-one-half hour lectures a day. The week-long
course is intended to provide a total of approximately 24 hours of
lectures and 3 hours of multigrid clinic on the various topics. Course
notes will be provided to all participants in order to facilitate
discussion during the lecture periods. The course topics and lecturers
are given below:

Pieter Hemker, CWI, The Netherlands
Multigrid and Defect Correction, Local Mode Two-Level Analysis,
Multigrid for Compressible Flows

Dimitri Mavriplis, ICASE, Hampton, VA
Overview of Unstructured Mesh Multigrid Methods, Nested Multi-
Level Grid Approach, Agglomeration Approach, Algebraic Multigrid

Shlomo Ta'asan, ICASE, Hampton, VA
Systems of PDE's, Discretization for Systems of PDE's, Relaxation
for Systems, Systems of Mixed Type, and Compressible Flows

Stefan Vandewalle, California Institute of Technology
Introduction to Parallel Computing, Parallel Implementation of
Standard Multigrid, Nonstandard Parallel Multigrid

Pieter Wesseling, Delft University of Technology, The Netherlands
Basics of Iterative Methods, Smoothing Analysis, Coarse Grid
Correction, Multigrid Methods

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 reply by June 15, 1994 by E-mail
or FAX to
Emily Todd
ICASE, Mail Stop 132C
NASA Langley Research Center
Hampton, VA 23681-0001

Phone: (804) 864-2175; E-mail:; FAX: (804) 864-6134


From: J. Cash <>
Date: Mon, 23 May 94 13:16:26 bst
Subject: Lectureships at Imperial College


As part of its continuing commitment to excellence in research and teaching,
the College is seeking to recruit a significant number of new lecturers.
These posts, to be known as the Governors' lectureships, will be permanent
and are intended for candidates of outstanding ability and potential.

The Mathematics Department of Imperial College will be bidding for a share
of these posts and is particularly interested in recruiting in the area of
Numerical Analysis.

Appointments will normally be made within the salary range #15,735 to
#27,241 per annum, including London Allowance, and will be from 1 October,
1994, or as soon as possible thereafter.

Potential candidates should send a CV and short description of research
interests to: Professor AFM Smith, Department of Mathematics, Imperial
College, 180 Queen's Gate, London SW7 2BZ; telephone 071 589 5111 ext5701;
FAX 071 225 8361; email

Applications should be made as soon as possible and, in any case, not later
than June 24, 1994.

Further information can also be obtained from


From: Petter Bjorstad <>
Date: Wed, 25 May 1994 15:42:38 +0200
Subject: Faculty Opening at University of Bergen

The CS department in Bergen has a faculty opening, within
the area of parallel computing/parallel algorithms, the
focus can be theoretical and/or computational.

A short version of the formal announcement follows:

Faculty opening at the
Department of Informatics, University of Bergen.

NATION: Norway

UNIVERSITY: University of Bergen, Department of Informatics

POSITION TITLE: "Forsteamanuensis" (Senior Lecturer or Assistant/Associate
Expected starting date is Spring 1995.


Professor Sigurd Meldal, Dept. Chairman
Phone: +47 555 44 176,

Tom Therkildsen, Administrative Manager
Phone: +47 555 44 182

Address: Dept. of Informatics, HiB, N-5020 Bergen, Norway
Fax: +47 555 44 199

POSITION DESCRIPTION: The Department of Informatics has an opening for a
"forsteamanuensis" (which corresponds more or less to the British Senior
Lecturer or the US range of Assistant to Associate Professor); initially
for a duration of four years.

Applicants must have obtained a Ph.D. or equivalent degree in informatics
(computer science), and should also document basic teaching skills.
(Applicants without teaching experience will be offered tutoring, and must
be able to document such skills within a year from the employment date.)

The department's areas of research focus are algorithms & complexity theory,
biocomputing, coding theory & cryptography, software engineering, scientific
computation, and optimization.

An interest in the development and analysis of methods for distributed and
parallel processing is a shared interest across all these. Applicants who are
well-qualified within the field of design and/or analysis of parallel
algorithms will be preferred.

Mastery of Norwegian is not a requirement initially. Courses may be given in
English the first two years of employment, and the textbooks are usually in

The salary is currently NOK 265 900 per year (approx. US$ 39,000).
Health insurance is universal in Norway, and foreigners may benefit from a
tax treaty, obtaining a reduced tax rate.


From: Jean Utke <>
Date: Thu, 26 May 1994 10:56:56 +0200
Subject: Position at Technical University of Dresden

C4-Professor of Geometry Position
Institute of Geometry
Faculty of Mathematics & Natural Sciences
Technical University of Dresden

" Geometry / Differential Geometry (C4) "
(registration number C4 010/W13)

The Technical University of Dresden invites outstanding candidates to
apply for a C4-professor of geometry faculty position in the Faculty of
Mathematics and Natural Sciences, Deptartment of Mathematics,
Institute of Geometry. The appointment would commence in 1995
and would fill the position currently held by G. Geise.

A candidate should have a Ph.D. in Mathematics and have a substantial
background in the area of geometry, in particular differential geometry,
and should be open-minded to applications in engineering. Experience in
CAGD will be regarded as desirable additional qualification, since this
is an area in which the Institute would like to be active.

A candidate is expected to give basic lectures for students of mathematics,
engineering, mathematical education, and specialized geometry lectures
for these students during their basic and topic-oriented study.
All lectures have to be given in German.
The ability and integrity to take part in the academic self-management
is required.

The Technical University of Dresden is interested in having a high quota of
women in research and teaching. Qualified female scientists
are particularly encouraged to apply. Applications of handicapped candidates
with equal qualification will be given preference.

Applications should contain curriculum vitae, photograph, description
of research achievements, list of papers, list of lectures given
and a confirmed copy of the document of the highest academic degree.
These materials should be sent no later than June 10, 1994 to

Technical University of Dresden
Faculty of Mathematics and Natural Sciences
01062 Dresden GERMANY

Since the time limit is very short applications may be announced via e-mail
to: Prof. A. Griewank,

Jean Utke Tel.: (+49) (0)351-463 2149
Technical University of Dresden
Institute of Scientific Computing
01062 Dresden GERMANY


From: Richard Brualdi <>
Date: Mon, 23 May 1994 16:08:17 -0500 (CDT)
Subject: Contents, Linear Algebra and its Applications

VOLUMES 203-204, MAY-JUNE, 1994

Third Special Issue on Linear
Systems and Control, Part I

Special Issue Editors:
A. C. Antoulas, M. L. J. Hautus, P. A. Fuhrmann,
and Y. Yamamoto

VOLUMES 205-206, JULY 1-JULY 15, 1994

Third Special Issue on Linear
Systems and Control, Part II

Special Issue Editors:
A. C. Antoulas, M. L. J. Hautus, P. A. Fuhrmann,
and Y. Yamamoto
Contents Volumes 203-204

Preface 1

Daniel Alpay and Vladimir Bolotnikov (Beer-Sheva, Israel)
On a General Moment Problem and Certain Matrix Equations 3

A. C. Antoulas (Houston, Texas)
A New Approach to Modeling for Control 45

J. A. Ball (Blacksburg, Virginia), M. A. Kaashoek (Amsterdam,
the Netherlands), G. Groenewald (Bellville, South Africa), and
J. Kim (Kwangju, Korea)
Column Reduced Rational Matrix Function With Given Null-Pole Data
in the Complex Plane 67

Joseph A. Ball (Blacksburg, Virginia), Marek Rakowski, and Bostwick F.
Wyman (Columbus, Ohio)
Coupling Operators, Wedderburn-Forney Spaces, and Generalized
Inverses 111

Wu Baowei (Xian, Shaanxi, People's Republic of China)
Some Properties of Linear Systems Defined Over a Commutative
Banach Algebra 139

Tibor Boros, Ali H. Sayed, and Thomas Kailath (Stanford, California)
Structured Matrices and Unconstrained Rational Interpolation Problems 155

Roger Brockett (Cambridge, Massachusetts)
Differential Equations and Matrix Inequalities on Isospectral Families 189

Chin Chang and Tryphon T. Georgiou (Minneapolis, Minnesota)
Geometric Aspects of the Caratheodory Extension Problem 209

Guanrong Chen (Houston, Texas) and Cetin Kaya Koc
(Corvallis, Oregon)
Computing Matrix-Valued Nevanlinna-Pick Interpolation 253

Gong-ning Chen and Hui-pin Zhang (Beijing, China)
More on Loewner Matrices 265

Carmen Coll, Rafael Bru, Elena Sanchez, and Vicente Hernandez
(Valencia, Spain)
Discrete-Time Linear Periodic Realization in the Frequency Domain 301

Ruth F. Curtain and Alejandro Rodriguez (Groningen, the Netherlands)
Necessary and Sufficient Conditions for J-Spectral Factorizations With
a J-Lossless Property for Infinite-Dimensional Systems in Continuous
and Discrete Time 327

Leonid Faybusovich (Notre Dame, Indiana)
Rational Functions, Toda Flows, and LR-like Algorithms 359

Avraham Feintuch (Beer-Sheva, Israel)
Strong Graph Representations for Linear Time-Varying Systems 385

Sven Feldmann (Stuttgart, Germany) and George Heinig
(Leipzig, Germany)
Uniqueness Properties of Minimal Partial Realizations 401

Michel Fliess (Gif-sur-Yvette, France)
Une Interpretation Algebrique de la Transformation de Laplace
et des Matrices de Transfert 429

Ciprian Foias (Bloomington, Indiana), Arthur Frazho (West Lafayette,
Indiana), and Allen Tannenbaum (Haifa, Israel)
On Combined H-H2 Suboptimal Interpolants 443

P. A. Fuhrmann (Beer-Sheva, Israel)
A Duality Theory for Robust Stabilization and Model Reduction 471

Hisaya Fujioka and Shinji Hara (Yokohama, Japan)
State Covariance Assignment Problem With Measurement Noise:
A Unified Approach Based on a Symmetric Matrix Equation 579

Ton Geerts (Tilburg, the Netherlands)
Linear-Quadratic Control With and Without Stability Subject to General
Implicit Continuous-Time Systems: Coordinate-Free Interpretations of the
Optimal Costs in Terms of Dissipation Inequality and Linear Matrix
Inequality: Existence and Uniqueness of Optimal Controls and
State Trajectories 607

Tomomichi Hagiwara and Mituhiko Araki (Kyoto, Japan)
A Successive Optimal Construction Procedure for State Feedback Gains 659

Author Index 674

Contents Volumes 205-206

Shinji Hara, Hisaya Fujioka (Yokohama, Japan), and
Pierre T. Kabamba (Ann Arbor, Michigan)
A Hybrid State-Space Approach to Sampled-Data Feedback Control 675

M. L. J. Hautus (Eindhoven, the Netherlands)
Operator Substitution 713

J. Hoffmann (Kaiserslautern, Germany) and P. A. Fuhrmann (Beer-Sheva, Israel)
Remarks on Orthogonal Polynomials and Balanced Realizations 741

J. Hoffmann and D. Pratzel-Wolters (Kaiserslautern, Germany)
Dipolynomial Minimal Bases and Linear Systems in AR Representation 777

E. W. Kamen (Atlanta, Georgia)
Block-Form Control of Linear Time-Invariant Discrete-Time Systems
Defined over Commutative Rings 805

Nicos Karcanias (London, United Kingdom)
Minimal Bases of Matrix Pencils: Algebraic Toeplitz Structure
and Geometric Properties 831

Tohru Katayama (Kyoto, Japan)
A Spectral Factorization Algorithm for Discrete-Time Descriptor
Systems via Generalized Eigenproblems 869

A. P. Kishore and J. B. Pearson, Jr. (Houston, Texas)
Kernel Representation and Properties of Discrete-Time
Input-Output Systems 893

Renee Koplon, Eduardo D. Sontag (New Brunswick, New Jersey), and
M. L. J. Hautus (Eindhoven, the Netherlands)
Observability of Linear Systems With Saturated Outputs 909

Hans-Andrea Loeliger (Linkoping, Sweden), G. David Forney, Jr.
(Mansfield, Massachusetts), Thomas Mittelholzer (Zurich, Switzerland),
and Mitchell D. Trott (Cambridge, Massachusetts)
Minimality and Observability of Group Systems 937

Denis Mustafa (Oxford, United Kingdom)
How Much Integral Action Can a Control System Tolerate? 965

M. A. Peters and A. A. Stoorvogel (Eindhoven, the Netherlands)
Mixed H2/H Control in a Stochastic Framework 971

Giorgio Picci and Stefano Pinzoni (Padova, Italy)
Acausal Models and Balanced Realizations of Stationary Processes 997

Allen C. Raines III and David S. Watkins (Pullman, Washington)
A Class of Hamiltonian-Symplectic Methods for Solving the
Algebraic Riccati Equation 1045

Cheryl B. Schrader (San Antonio, Texas)
Dynamical Structures on Pencils, Poles, and Fundamental Subspaces 1061

J. A. Sefton and R. J. Ober (Richardson, Texas)
Hankel-Norm Approximation and Control Systems 1081

J. de Does and J. M. Schumacher (Amsterdam, the Netherlands)
Continuity of Singular Perturbations in the Graph Topology 1121

Alle-Jan van der Veen and Patrick Dewilde (Delft, the Netherlands)
On Low-Complexity Approximation of Matrices 1145

Xiaochang Wang (Lubbock, Texas) and Joachim Rosenthal (Notre Dame,
A Cell Structure for the Set of Autoregressive Systems 1203

Siep Weiland (Eindhoven, the Netherlands)
A Behavioral Approach to Balanced Representations of Dynamical
Systems 1227

Harald K. Wimmer (Wurzburg, Germany)
A Galois Correspondence Between Sets of Semidefinite Solutions of
Continuous-Time Algebraic Riccati Equations 1253

Q.-H. Wu and M. Mansour (Zurich, Switzerland)
On the Stability Hyperellipsoid of a Schur Polynomial 1271

Xin Xin and Hidenori Kimura (Osaka, Japan)
(J, J')-Lossless Factorization for Descriptor Systems 1289

Yutaka Yamamoto and Mituhiko Araki (Kyoto, Japan)
Frequency Responses for Sampled-Data Systems - Their Equivalence and
Relationships 1319

Author Index 1341


From: SIAM <>
Date: Thu, 26 May 94 09:49:14 EST
Subject: Contents, SIAM Control & Optimization

SIAM Journal on Control and Optimization
Volume 32, Number 5, September 1994

On the Solutions of a Class of Continuous Linear Programs
Edward J. Anderson and Andrew B. Philpott

The Riccati Equation for Optimal Control Problems with Mixed
State-Control Constraints: Necessity and Sufficiency
Vera Zeidan

A Multistate, Multicontrol Problem with Unbounded Controls
J. R. Dorroh and Guillermo Ferreyra

Numerical Approximations for Hereditary Systems with Input and
Output Delays: Convergence Results and Convergence Rates
A. Manitius and H. T. Tran

Root Locus and Boundary Feedback Design for a Class of Distributed
Parameter Systems
D. Gilliam, Christopher I. Byrnes, and Jianqiu He

Optimal Controls of Navier-Stokes Equations
Mihir Desai and Kazufumi Ito

Necessary Conditions for Optimal Control of Stochastic Systems with
Random Jumps
Shanjian Tang and Xunjing Li

Nonsmooth Optimum Problems with Constraints
Zs. Pales and V. M. Zeidan

Stability of Recursive Stochastic Tracking Algorithms
Lei Guo

Uniform Exponential Stability and Approximation in Control of a
Thermoelastic System
Zhuangyi Liu and Songmu Zheng

Asymptotic First Hitting Time Distribution of Annealing Processes
Christian Mazza

The Asymptotic Behavior of Simulated Annealing Processes with
Tzuu-Shuh Chiang and Yunshyong Chow


From: Ralph B Kearfott <>
Date: Fri, 27 May 1994 15:19:24 -0500
Subject: Contents, Interval Computations

Contents, Interval Computations
First special issue on the proceedings of the conference on

Numerical Analysis with Automatic Result Verification
Lafayette, Louisiana
February 25 to March 1, 1993


Foreword by Prof. R. B. Kearfott 4

F.L.Alvarado and Zian Wang
Direct Sparse Interval Hull Computations for Thin
Non-M-Matrices 5

A.B.Babichev, O.B.Kadyrova, T.P.Kashevarova,
A.S.Leshchenko, and A.L.Semenov
UniCalc, a Novel Approach to Solving Systems
of Algebraic Equations 29

D. Berleant
Automatically Verified Reasoning with Both
Intervals and Probability Density Functions 48

O. Caprani, B. Godthaab, and K. Madsen
Use of a Real-Valued Local Minimum in Parallel Interval
Global Optimization 71

I. Cervesato, A. Montanari, A. Provetti
On the Non-monotonic Behaviour of Event Calculus
for Deriving Maximal Time Intervals 83

A.E.Connell and R.M.Corless
An Experimental Interval Arithmetic Package in Maple 120

J.S. Ely
The VPI Software Package for Variable Precision
Interval Arithmetic 135

J. Garloff
The Bernstein Algorithm 154

Solving Large Systems of Nonlinear Constraints with
Application to Data Modeling 169


Applications of Interval Computations: International
Workshop 201

Requirements for manuscript preparation 205

Addresses of the editorial board members 207


From: Iain Duff <>
Date: Sat, 28 May 94 11:40:54 BST
Subject: Contents, IMA Numerical Analysis

IMA JOURNAL OF NUMERICAL ANALYSIS. Volume 14 Number 3. July 1994.

McLean W and Sloan I H
A fully discrete and symmetric boundary element method.

Baker C T H and Paul C A H
Computing stability regions --- Runge-Kutta methods for delay
differential equations.

Hundsdorfer W
On the error of general linear methods for stiff dissipative
differential equations.

Beyn W-J
Numerical analysis of homoclinic orbits emanating from a
Takens-Bogdanov point.

Mannikko T, Neittaanmaki P, and Tiba D
A rapid method for the identification of the free boundary in
two-phase Stefan problems.

French D A and Jensen S
Long-time behaviour of arbitrary order continuous time Galerkin
schemes for some one-dimensional phase transition problems.

Pytlak R
On the convergence of conjugate gradient algorithms.


End of NA Digest