NA Digest Sunday, May 12, 1996 Volume 96 : Issue 19

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

Submissions for NA Digest:

Mail to na.digest@na-net.ornl.gov.

Mail to na.help@na-net.ornl.gov.

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

From: Dirk Laurie <dirk@calvyn.puk.ac.za>
Date: Mon, 6 May 1996 08:54:03 +0200 (SAT)
Subject: What Is the Best Set of Independent Rows?

In NA Digest 96:12 I asked:

Given an m x n matrix of rank r, which set of r rows has the smallest
condition number? (Condition number = s_1/s_r, where {s_i} are the
singular values of the chosen submatrix in non-increasing order.)

It turns out that although nobody has studied this precise problem,
the question of selecting a subset of r rows, optimized for some other
criterion of non-singularity, is a venerable and much-studied one.

Like most questions in numerical linear algebra, the first thing that
you find out is GENE WAS HERE.

1. P.A. Businger and G.H. Golub, Linear least squares solution
by Householder transformations, Numer. Math. 7 (1965) 269--276.
2. G.H. Golub, V. Klema and G.W. Stewart, Rank degeneracy and least
squares problems, Technical Report TR-456, Department of Computer
Science, University of Maryland, 1976.
3. G.H. Golub and C. van Loan, Matrix Computations.
Section 12.2 in the first edition, 1983.

These references deal with the equivalent problem of selecting columns.
[1] gives the original HFTI (Householder forward triangularization with
interchanges) algorithm, [2] a better one based on first finding an
orthogonal basis for the row space (using the SVD, of course) and only
then doing HFTI on those vectors. [3] summarizes [2].

Other related work is:

4. F.R. de Hoog and R.M.M. Mattheij, Subset selection for matrices,
Report RANA 89-07, Eindhoven University of Technology, 1989.
This work finds an rxr submatrix B that maximizes det(B).

5. Khachian, circa 1994 (exact reference not available), on the
related problem of finding an rxr submatrix B that minimizes
||B^{-1}||.

The answer that I loved and hated most was:

"Anyway, this is a famous problem for which the only algorithm I know
is to try the m choose r possiblities and recompute the condition number
in each case."

Thanks to everybody who responded.

Dirk Laurie

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

From: Jemal Sanikidze <jemal@compmath.acnet.ge>
Date: Tue, 7 May 96 16:18:11 +0400
Subject: Georgian Group Seeking Research Partners

Dear Colleagues,
A scientific team of Georgian (Former Soviet Union) mathematicians
working at Georgian Technical University (Tbilisi) will be glad to
find an American partner. Our aim is to submit a project to
OCEE@NAS.EDU
Interested mathematicians are requested to contact (prompt
e-mail: gmu@imath.acnet.ge
jemal@compmath.acnet.ge
We offer the collaboration in the following areas:
Problems of elasticity for bodies with cuts.
Two - and three dimensional problems of elasticity and
thermoelasticity theory for homogeneous and piecewise homogeneous
anisotropic bodies and two-component elastic composites (mixtures)
with interior cuts.
By the methods of boundary integral equations wide classes
of boundary value and interface problems (including the interface
crack type problems) will be investigated. The asymptotics of solutions
will be studied near the edge points. The methods of boundary elements
and regular sourses will be applied for constructing approximate
numerical solutions.
Solutions of particular problems for domains with concrete geometry
(domains surrounded by spheres and planes) will be constructed
Coordinator of the Georgian group
Prof. Dr. David Natroshvili

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

From: Lieven Vandenberghe <vandenbe@isl.stanford.edu>
Date: Thu, 9 May 1996 19:50:36 -0700 (PDT)
Subject: Notes on Convex Optimization with Engineering Applications

We have made available the lecture notes for a new course,
Introduction to Convex Optimization with Engineering
Applications, taught for the first time spring quarter 1995.

You can find the lecture notes on the WWW at URL
http://www-isl.stanford.edu/people/boyd/392/ee392x.html
or retrieve them by anonymous ftp at isl.stanford.edu
in /pub/boyd/392.

Any comments will be greatly appreciated.

Stephen Boyd
Lieven Vandenberghe

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

From: Jan Kok <Jan.Kok@cwi.nl>
Date: Tue, 7 May 1996 12:28:57 +0200
Subject: Dutch Numerical Mathematics Conference

ANNOUNCEMENT WOUDSCHOTEN CONFERENCE 1996

The annual conference of the Dutch Community of Numerical Mathematicians
(WNW) has been scheduled for 25, 26 and 27 September 1996, to be held
at the Woudschoten Conference Centre, Zeist, The Netherlands.

Topics of this year's conference are:
1) iterative solution methods for highly non-symmetric systems of equations,
2) numerical algorithms for transport equations.

Invited speakers are:
Theme 1: Peter A. Forsyth (U. of Waterloo, Ontario),
Thomas Huckle (TU M"unchen),
Theme 2: Rolf Jeltsch (ETH Z"urich),
Brian P. Leonard (The U. of Akron, Ohio),
David L. Williamson (NCAR, Boulder).

Contributed, 30-minute presentations:
The programme allows incorporation of about four contributed presentations by
participants, relevant to either of the conference topics.

For all information see the conference WWW page, URL:
http://www.cwi.nl/~jankok/woudschotEn.html
or contact the secretary of the organizing committee,
Jan Kok
CWI - Centrum voor Wiskunde en Informatica
P.O. Box 94079
NL-1090 GB Amsterdam
Telephone: +31 20 592 4107 (fax: ..-4199) E-mail: Jan.Kok@cwi.nl

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

From: Trini Flores <flores@siam.org>
Date: Wed, 08 May 96 17:22:02 EST
Subject: Symposium on Networks and Information Management

Symposium on Networks and Information Management (NIM)
Monday, May 27, 1996

Sponsored by SIAM in cooperation with the Department of Computer and
Information Science, University of Pennsylvania.

Additional information regarding the Symposium can be accessed in
electronic format through the World Wide Web:

http://www.acm.org
http://www.siam.org/meetings/fcrcC96/fcrchome.htm

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

From: Mei Kobayashi <mei@trl.ibm.co.jp>
Date: Fri, 10 May 1996 10:53:02 +0900
Subject: Wavelet Seminars at IBM Tokyo

Wavelet Seminars at IBM Tokyo Research Laboratory, July 02, 1996 (Tues)

Tentative program: five 1 hour talks on case studies of applications
of wavelets from 10:00-17:00. There will be ample time for informal
discussions with speakers and attendees during coffe breaks and lunch.

1. Prof. Yamada Michio (Tokyo U)
biorthogonal wavelets and analysis of winds and seismic waves
2. Prof. Sakakibara (Iwaki Meisei U)
de-noising lab signals using wavelets
3. Prof Hisa Kikuchi (Niigata Univ)
image processing using wavelets
4. Prof Nakashizuka (Niigata Univ)
ECG signal analysis using wavelets
5. Mei Kobayashi (IBM & Tokyo U)
speech signal analysis using wavelets

100 seats will be available to members of the general the public who would
like to attend (first come, first serve basis). Charge: free.
If you would like to attend the seminars, pls. send the following info.
(in ENGLISH, in the format given below) to mei@trl.ibm.co.jp

example: LAST NAME, first name, affiliation, e-mail
KOBAYASHI, Mei, IBM Tokyo Research Laboratory, mei@trlvm.ibm.co.jp

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

From: Catherine Rachwalski <crachwal@carbon.cudenver.edu>
Date: Fri, 10 May 1996 13:46:34 -0600
Subject: 1997 Copper Mountain Multigrid Conference

ANNOUNCING THE 1997
COPPER MOUNTAIN CONFERENCE
ON MULTIGRID METHODS

TO BE HELD
APRIL 6-11, 1997

TENTATIVE SHEDULE IS AS FOLLOWS:

Sunday, April 6 - Reception & Registration 7:00 p.m. - 9:00 p.m.
Monday, April 7 - 8:00 - 12:00 meeting 4:00 - 7:00 meeting
Tuesday, April 8 - 8:00 - 12:00 meeting 4:00 - 7:00 meeting
Wednesday, April 9 - 8:00 - 12:00 meeting 4:00 - 6:00 meeting
7:00 - 9:00 p.m. Banquet
Thursday, April 10 - 8:00 - 12:00 meeting 4:00 - 6:00 meeting
Friday, April 11 - 8:00 - 12:00 meeting 4:00 - 6:00 meeting

This schedule is subject to change.

Further information will be available later this summer.

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

Date: Thu, 9 May 1996 16:38:09 +0100 (BST)
Subject: New Book Series: Computational Economics and Finance

Announcing a New Book Series from Harwood Academic Publishers

Computational Economics and Finance

Editor: Seth A. Greenblatt, University of Reading

Editorial Board: Kenneth L. Judd, Stanford University
Manfred Gilli, University of Geneva
Carl Chiarella, University of Technology, Sydney

This proposed new series will present high quality research monographs
and themed collections written from a variety of perspectives and at
different levels of technical sophistication. Problems addressed in
Economics, Finance, and Econometrics are increasing in complexity and
Fortunately, advances in computing hardware has allowed us to solve
problems that researchers would not have dreamt of attempting in the
past. The solution of these new problems requires the development of
innovative, efficient computational methods. Computational Economics
and Finance are rapidly expanding fields that have arisen in order to
meet these challenges.

The Editor welcomes proposals and manuscripts for the series that
include, but are not limited to:

o New numerical methods or symbolic computation techniques developed
for the solution of problems in Economics, Finance, and Econometrics

o Innovative uses of computational methods developed in other fields
as applied to Economic, Financial, and Econometric Problems

o Techniques for the analysis or solution of nonlinear problems

o Innovative computationally-oriented methods for modeling economic
behavior (artificial neural networks, genetic algorithm, cellular
automata, etc.)

o Computational approaches to mathematical programming and optimal
control problems

o Computational Statistical techniques (time-frequency methods,
flexible functional form estimation, resampling methods,
classification methods, forecasting techniques, etc.)

o Novel simulation methods

o Numerical linear algebra

o Application of computational approximation theory

Please send three (3) copies of proposals or manuscripts either to the
Editor:

Dr. Seth A. Greenblatt
Director, Centre for Quantitative Economics and Computing
Department of Economics
Faculty of Letters and Social Sciences
PO Box 218
Whiteknights
UK

or to your nearest member of the Editorial Board:

Dr. Kenneth L. Judd
Senior Fellow
Hoover Institution
Stanford University
Stanford, CA 94305
USA

Professor Manfred Gilli
University of Geneva
Department of Econometrics
Boulevard Carl Vogt 102
Geneva, 1211
SWITZERLAND

Professor Carl Chiarella
University of Technology, Sydney
School of Finance and Economics
P.O. Box 123
AUSTRALIA

The Editor will be available to discuss potential book projects at the
Second International Conference on Computing in Economics and Finance
in Geneva from the 26th to the 28th of June 1996.

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

From: Omar Hamed <F40M001%SAKSU00.BITNET@VTBIT.CC.VT.EDU>
Date: Sun, 12 May 96 16:30:21 SLT
Subject: Positions Available in Saudia Arabia

The National Center of Mathematical Sciences has been established
in Saudi Arabia. One of its goals is to encourage research in various
fields of the Mathematical Sciences.
The center has a visitor programme for 2 senior mathematicians in
each academic year to spend a period of one to several weeks between
October and June.
The visitor is expected to deliver several lectures in his field
and to interact with mathematicians in Saudi uninversities.
We are inviting interested mathematicians to send their c.v.'s
by mail to:
The National Center of Mathematical Sciences
c/o Department of Mathematics
College of Science
King Saud University
P.O.Box 2455

SINCERELY YOURS,

DR.O.M.S. HAMED
DEPARTMENT OF MATHEMATICS
KING SAUD UNIVERSITY
SAUDI ARABIA.
EMAIL: F40M001@SAKSU00.BITNET
TEL ++ 966 1 4676520 FAX ++ 966 1 4676512

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

From: E. B. Saff <esaff@gauss.math.usf.edu>
Date: Tue, 7 May 1996 17:05:30 -0400
Subject: Contents, Constructive Approximation

1 P. E. T. Jorgensen and S. Pedersen
Harmonic Analysis of Fractal Measures

31 Bl. Sendov
Mathematical Modeling of Real-World Images

67 K. Kopotun
Simultaneous Approximation by Algebraic Polynomials

95 T. Kilgore and J. Prestin
Polynomial Wavelets on the Interval

111 A. Kamont
On Hyperbolic Summation and Hyperbolic Moduli of Smoothness

127 G. Plonka
Generalized Spline Wavelets

RESEARCH PROBLEMS

157 A. Ambroladze and H. Wallin
A Convergence Problem for Rational Interpolants with
Preassigned Poles: Research Problem 96-1

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

From: SIAM <tschoban@siam.org>
Date: Thu, 09 May 96 12:22:53 EST
Subject: Contents, SIAM Scientific Computing

SIAM Journal on Scientific Computing
JULY 1996, Volume 17, Number 4
CONTENTS

Comparisons of Lattice Boltzmann and Finite Difference Methods for
a Two-Dimensional Viscous Burgers Equation
Bracy H. Elton

Direct Numerical Calculations of a Neutral Stability Curve for One-
Dimensional Detonations
Wei Cai, Wonho Oh, and Youlan Zhu

ILUM: A Multi-Elimination ILU Preconditioner for General Sparse Matrices

Efficient Algorithms for Computing a Strong Rank-Revealing QR Factorization
Ming Gu and Stanley C. Eisenstat

Parallelizing the QR Algorithm for the Unsymmetric Algebraic
Eigenvalue Problem: Myths and Reality
Greg Henry and Robert van de Geijn

An Overdetermined Schwarz Alternating Method
Huosheng Sun and Wei-Pai Tang

Random Relaxation of Fixed-Point Iteration
Markku Verkama

Rapid Computation of the Discrete Fourier Transform
Chris Anderson and Marie Dillon Dahleh

Fast Recursive Least Squares Adaptive Filtering by Fast Fourier
Michael K. Ng and Robert J. Plemmons

A Convolution Algorithm with Application to Data Assimilation
Ranjit M. Passi, R. Kent Goodrich, Mark Limber, and John C. Derber

A General Heuristic for Choosing the Regularization Parameter in
Ill-Posed Problems
Martin Hanke and Toomas Raus

Bayesian-Validated Surrogates for Noisy Computer Simulations;
Application to Random Media
Serhat Yesilyurt, Chahid K. Ghaddar, Manuel E. Cruz, and Anthony T. Patera

Primal-Dual Combinatorial Relaxation Algorithms for the Maximum
Degree of Subdeterminants
Satoru Iwata, Kazuo Murota, and Izumi Sakuta

Verification May Be Better Than Estimation
C. Falco Korn, B. Hormann, and C. P. Ullrich

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End of NA Digest

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