### Today's Editor:

- Cleve Moler
- The MathWorks, Inc.
- moler@mathworks.com

- Moving Boundary Problems
- Elliptic PDE Solver Sought
- Numerical Mathematics, A Laboratory Approach
- Eigensystem Solver for Pentadiagonal Systems
- Workshop at Bath
- Post Doc Position at Battelle Pacific Northwest Laboratory
- Contents: Linear Algebra and its Applications

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

From: Pasqua D'Ambra <pasqua@vm.cised.unina.it>

Date: Thu, 22 Jul 93 13:26:13 EDT

**Subject: Moving Boundary Problems**

I am a Ph.D. Student and I am working on my thesis.

The subject is "Moving boundary problems (Stefan Problems)".

I would like to have contacts with other researchers in the field and

I would like to receive recent references about resolution of these problems

on parallel machines.

PASQUA D'AMBRA PHONE: +39 81 675624

Universita' di Napoli FAX : +39 81 7662106

dip. matematica e applicazioni E-MAIL: PASQUA@VM.CISED.UNINA.IT

80126 Napoli Italia

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

From: Vladimir Oliker <oliker@mathcs.emory.edu>

Date: Mon, 19 Jul 93 09:32:37 -0400

**Subject: Elliptic PDE Solver Sought**

I am looking for a high accuracy linear elliptic PDE-solver that can

deal with general boundary conditions in 2-d domains with curved boundaries;

for example, on an ellipse.

Any help will be greatly appreciated.

Vladimir Oliker

oliker@mathcs.emory.edu

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

From: Eugene Isaacson <ISAACSON@ACFcluster.NYU.EDU>

Date: Tue, 20 Jul 1993 16:18:42 -0500 (EST)

**Subject: Numerical Mathematics, A Laboratory Approach**

Just Published.

"Numerical Mathematics - A Laboratory Approach", by Shlomo Breuer & Gideon Zwas

Cambridge University Press, 267 p.

Most noteworthy for its unique use of the microcomputer laboratory to

treat algorithmic aspects of mathematics - without calculus or linear algebra.

Here is a mathematically rigorous development in eight chapters:

1. Mathematics in a numerical laboratory;

2. Iterations for root extractions;

3. Area approximations;

4. Linear systems - an algorithmic approach;

5. Algorithmic computations of pi and e;

6. Convergence acceleration;

7. Interpolative approximation;

8. Computer library functions.

Suitable for first year college students; training mathematics teachers;

and gifted high school students.

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

From: Imran Bhutta <BHUTTA@VTVM1.CC.VT.EDU>

Date: Wed, 21 Jul 93 11:20:56 EDT

**Subject: Eigensystem Solver for Pentadiagonal Systems**

Dear Editor(s),

I am developing a Semiconductor Device Simulator using Quantum

Mechanical approach. It is a 2-D simulator and at one point involves the

solution of the Schrodinger's equation. That is to say I have to find the

eigenvalues and corresponding eigenvectors for that system of equations. For

a 2-D system with 100 points in 'x' and 'y' directions, my eigen system matrix

is a n**2 by n**2 i.e., 10,000 by 10,000. This matrix is a pentadiagonal

matrix, with a diagonal vector and two subdiagonals and two superdiagonals.

The subdiagonals lie at 'i-1' and 'i-5' and the superdiagonals lie at 'i+1' and

'i+5'. It is a highly sparse matrix, which is real and symmetric.

I am looking for a routine that would help me solve this

pentadiagonal eigen system. I have routines for tridiagonal systems, and my

first approach was to reduce my pentadiagonal matrix to a tridiagonal form by

Householder's scheme. However Householder's scheme generates an orthogonal

matrix alongwith the tridiagonal matrix, and I do not gain any advantage in

space saving, since the orthogonal matrix is not pentadiagonal. If someone

can suggest a solution technique I would appreciate it very much. My e-mail

address is BHUTTA@VTVM1.CC.VT.EDU. I appreciate your help very much. Thank

you.

Imran A. Bhutta

EE Department

Virginia Tech

Blacksburg, VA 24061-0111

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

From: I. G. Graham <I.G.Graham@maths.bath.ac.uk>

Date: Mon, 19 Jul 93 9:57:34 BST

**Subject: Workshop at Bath**

Dear Colleagues,

This is to inform you that there will be an informal workshop on iterative

methods for PDE at the University of Bath, U.K. on September 6th 1993.

The two principal speakers are Professor Wolfgang Hackbusch (University of

Kiel, Germany) and Professor Dan Sorensen (Rice University, Texas).

There will also be a number of contributed talks from U.K. researchers.

Best wishes,

Ivan Graham (igg@maths.bath.ac.uk)

Iterative methods for large computational problems arising from PDEs

A Workshop at the University of Bath

Monday 6th September 1993 -- Building 6E, Room 2.2

Wolfgang Hackbusch (Christian Albrechts Universit\"{a}t, Kiel, Germany):

On the frequency decomposition multi-grid method.

Kevin Parrott and Tony Ware (Oxford University Computing Laboratory):

Parallel multi-grid for a 3-D tensor diffusion problem with block-discontinuous

coefficients

Mike Wilson (School of Mechanical Engineering, University of Bath):

Parallel multi-grid computation of rotating disc flows

Paul Crumpton (Oxford University Computing Laboratory):

Multi-grid for non-nested grids on a parallel computer

Dan Sorensen (Rice University):

Variations on Arnoldi's method for large scale eigenvalue problems

Mark Hagger and Alastair Spence (School of Mathematical Sciences, Bath):

Polynomial preconditioning for conjugate gradient methods

Rob Coomer and Ivan Graham (School of Mathematical Sciences, Bath):

Mesh-independent fixed point iteration and domain decomposition

for semiconductor device equations in 2D

All interested persons are welcome to attend. There will be no

registration fee. However, in order that we can inform the catering

department about the numbers for lunch it would be helpful if those

who intend to come could inform us before August 27th by email

to Ivan Graham at igg@maths.bath.ac.uk or by telephone to Sarah Love

at (0225) 826198 or School of Mathematical Sciences, University of Bath,

Bath BA2 7AY, U.K.

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

From: George Fann <gi_fann@pnl.gov>

Date: Wed, 21 Jul 93 10:03:56 PDT

**Subject: Post Doc Position at Battelle Pacific Northwest Laboratory**

Post-doc Opening starting Oct. 1993

Battelle Pacific Northwest Laboratory

The Analytic Sciences Department of the Pacific Northwest Laboratory

is inviting applications for a postdoctoral research position. The

appointment is initially for a one-year term. The successful

candidate will participate in a project for computational fluid

dynamics and numerical linear algebra algorithms for MIMD parallel

computers ( e.g. Touchstone DELTA, or clusters of HP 9000/735 and IBM

RS6000/560 workstations).

We are looking for an individual to implement and investigate recent

algorithm advances in solving elliptic and parabolic equations using

the finite volume formulation.

This project is interdisciplinary in nature and interfaces with

efforts in numerical analysis, parallel computing, large-scale

simulation of physical processes, and programming tools. Project

members have access to state-of-the art computing facilities,

including a 520-processor Intel Touchstone DELTA. Nominal

requirements include a Ph.D. in computer science, applied mathematics,

or an applied science or engineering discipline. A good algorithms

background and hands-on experience in some aspect of scientific

computing is necessary.

Applications must be addressed to George Fann, ms: K7-15 Pacific

Northwest Laboratory, Battelle Blvd, Richland, WA 99352, or via e-mail

to gi_fann@pnl.gov. The application must include a resume and the

names and addresses of three references.

For further information, contact George Fann, gi_fann@pnl.gov.

Fax:(509) 375-3641.

Battelle is an affirmative action/equal opportunity employer. Legal

right to work in U.S. is required -- U.S. Citizenship preferred.

Pacific Northwest Laboratory is a U.S. Department of Energy

laboratory.

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

From: Richard Brualdi <brualdi@math.wisc.edu>

Date: Wed, 21 Jul 1993 08:36:20 -0500 (CDT)

**Subject: Contents: Linear Algebra and its Applications**

LINEAR ALGEBRA AND ITS APPLICATIONS

Contents Volumes 188/189

Preface 1

Dario Bini (Pisa, Italy) and Victor Pan (Bronx, New York)

Improved Parallel Computations With Toeplitz-like

and Hankel-like Matrices 3

Adam W. Bojanczyk (Ithaca, New York), James G. Nagy (Dallas, Texas),

and Robert J. Plemmons (Winston-Salem, North Carolina)

Block RLS Using Row Householder Reflections 31

Stephen Boyd (Stanford, California) and Laurent El Ghaoui

(Paris, France)

Method of Centers for Minimizing Generalized Eigenvalues 63

Ralph Byers (Lawrence, Kansas) and N. K. Nichols

(Reading, United Kingdom)

On the Stability Radius of a Generalized State-Space System 113

Biswa Nath Datta and Fernando Rincon (De Kalb, Illinois)

Feedback Stabilization of a Second-Order System:

A Nonmodal Approach 135

Bart De Moor (Leuven, Belgium)

Structured Total Least Squares and L2 Approximation Problems 163

Ludwig Elsner and Chunyang He (Bielefeld, Deutschland)

Perturbation and Interlace Theorems for the Unitary

Eigenvalue Problem 207

Michael K. H. Fan (Atlanta, Georgia)

A Quadratically Convergent Local Algorithm on Minimizing

the Largest Eigenvalue of a Symmetric Matrix 231

Roland W. Freund (Murray Hill, New Jersey) and Hongyuan Zha

(University Park, Pennsylvania)

Formally Biorthogonal Polynomials and a Look-ahead

Levinson Algorithm for General Toeplitz Systems 255

Mei Gao and Michael Neumann (Storrs, Connecticut)

A Global Minimum Search Algorithm for Estimating the

Distance to Uncontrollability 305

Martin H. Gutknecht (Zurich, Switzerland)

Stable Row Recurrences for the Pade Table and

Generically Superfast Lookahead Solvers for

Non-Hermitian Toeplitz Systems 351

A. Scottedward Hodel (Auburn, Alabama)

Computation of System Zeros With Balancing 423

W. W. Lin (Hsin-Chu, Taiwan) and S. S. You (Chung-Li, Taiwan)

A Symplectic Acceleration Method for the Solution

of the Algebraic Riccati Equation on a Parallel

Computer 437

Lin-Zhang Lu (Fujian, China) and Wen-Wei Lin (Hsinchu, Taiwan)

An Iterative Algorithm of the Solution of the

Discrete-Time Algebraic Riccati Equation 465

Alexander N. Malyshev (Novosibirsk, Russia)

Parallel Algorithm for Solving Some Spectral Problems

of Linear Algebra 489

Pradeep Misra (Dayton, Ohio) and Thulasinath Manickam

(Kingston, Rhode Island)

Balanced Realization of Separable-Denominator

Multidimensional Systems 521

Marc Moonen (Heverlee, Belgium), Paul Van Dooren

(Urbana, Illinois), and Filiep Vanpoucke (Heverlee, Belgium)

On the QR Algorithm and Updating the SVD and

the URV Decomposition in Parallel 549

W. H. L. Neven (Emmeloord, the Netherlands) and C. Praagman

(Groningen, the Netherlands)

Column Reduction of Polynomial Matrices 569

R. V. Patel (Montreal, Quebec, Canada)

On Computing the Eigenvalues of a Symplectic Pencil 591

Vassilis Syrmos (Honolulu, Hawaii) and Petr Zagalak

(Prague, Czechoslovakia)

Computing Normal External Descriptions and Feedback Design 613

David H. Wood (Newark, Delaware)

Product Rules for the Displacement of Near-Toeplitz Matrices 641

Dragan Zigic, Layne T. Watson, and Christopher Beattie

(Blacksburg, Virginia)

Contragredient Transformations Applied to the Optimal

Projection Equations 665

Author Index 677

LINEAR ALGEBRA AND ITS APPLICATIONS

Contents Volume 190

Jack B. Brown (Auburn, Alabama), Phillip J. Chase

(Ft. Meade, Maryland), and Arthur O. Pittenger

(Baltimore, Maryland)

Order Independence and Factor Convergence in Iterative

Scaling 1

James S. Otto (Denver, Colorado)

Multigrid Convergence for Convection-Diffusion Problems

on Composite Grids 39

Hassane Sadok (Villeneuve d'Ascq-Cedex, France)

Quasilinear Vector Extrapolation Methods 71

Han H. Cho (Seoul, Korea)

Prime Boolean Matrices and Factorizations 87

J. B. Wilker (Scarborough, Ontario, Canada)

The Quaternion Formalism for Mobius Groups in Four

or Fewer Dimensions 99

Martin Hanke (Karlsruhe, Germany) and Michael Neumann

(Storrs, Connecticut)

The Geometry of the Set of Scaled Projections 137

Joel E. Cohen (New York, New York) and Uriel G. Rothblum

(Haifa, Israel)

Nonnegative Ranks, Decompositions, and Factorizations

of Nonnegative Matices 149

Carolyn A. Eschenbach (Atlanta, Georgia) and Charles R. Johnson

(Williamsburg, Virginia)

Sign Patterns That Require Repeated Eigenvalues 169

Raymond H. Chan and Kwok-Po Ng (Hong Kong, People's

Republic of China)

Toeplitz Preconditioners for Hermitian Toeplitz Systems 181

Roger A. Horn (Salt Lake City, Utah) and Dennis I. Merino

(Hammond, Louisiana)

A Real-Coninvolutory Analog of the Polar Decomposition 209

M. H. Lim (Kuala Lumpur, Malaysia)

A Note on Similarity Preserving Linear Maps on Matrices 229

Miroslav Fiedler and Zdenek Vavrin

(Praha, Czech Republic)

Polynomials Compatible With a Symmetric Loewner Matrix 235

William A. Adkins (Baton Rouge, Louisiana), Jean-Claude Evard

(Laramie, Wyoming), and Robert M. Guralnick

(Los Angeles, California)

Matrices Over Differential Fields Which Commute With Their

Derivative 253

Author Index 263

Contents 190, September

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End of NA Digest

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