krj@na.toronto.edu (Ken Jackson) (09/26/88)
NA Digest Sunday, September 25, 1988 Volume 88 : Issue 38 Today's Editor: Cleve Moler Today's Topics: Fourth Parallel Circus Factoring Polynomials Position in North Carolina Riccati Equation Meeting in Italy Nineteenth Annual USL Mathematics Conference Dundee Biennial NA Conference 1989 Position in OR at Stanford ------------------------------------------------------- From: Apostolos Gerasoulis <gerasoul@aramis.rutgers.edu> Date: Sun, 18 Sep 88 13:35:45 EDT Subject: Fourth Parallel Circus FOURTH PARALLEL CIRCUS RUTGERS University, New Brunswick, New Jersey, December 2-3, 1988 THEME: Parallel Numerical Algorithms, Programming Tools and Applications. OBJECTIVE: The meeting is an informal gathering of researchers interested in parallel processing. The intention is to discuss recent results in the area and exchange ideas for future work. The atmosphere is completely casual and the speakers are chosen at the beginning of the circus. To encourage easy discussion, there are no formal proceedings. We hope that about 50 persons will be in attendance and there are no parallel sessions. HISTORY: It has been customary for the circus to be held twice a year during Friday and Saturday. The first Parallel Circus was held in May 1987 at Yale (Chaired by Prof. M. Schultz), the second at Cornell in November 1987, (chaired by Prof. Van Loan), and the third at IBM Kingston (organized by V. Sonnad and chaired by Prof. G. Golub and M. Schultz). PLACE: The Fourth Parallel Circus is organized by Rutgers University and will be held at the Hyatt Regency Hotel at New Brunswick, New Jersey (chaired by G. Golub and A. Gerasoulis). New Brunswick is located between New York (35 miles southwest) and Philadelphia and is easily accessible via plane (Newark airport), train and automobile. CONTACTS: If you wish to attend please contact Prof. Apostolos Gerasoulis or Ms. Priscilla Rasmussen as soon as possible. PHONE: (201)-932-2725/2768, E-MAIL: gerasoulis@aramis.rutgers.edu, rasmussen@aramis.rutgers.edu, ADDRESS: Department of Computer Science, Rutgers University, New Brunswick, NJ 08903. If you wish to present your work at the meeting include the title of your talk in your message. DEADLINES: The reservation cut off date for the conference rate at the Hyatt is 11/10/88. ------------------------------ From: Rolf Jeltsch <JELTSCH%DACTH51.BITNET@Forsythe.Stanford.EDU> Date: Mon, 19 Sep 88 10:51:21 CET Subject: Factoring Polynomials A collegue of mine, Prof. Plesken has asked me whether numerical analysts know the following algorithm to compute factors of polynomials. I would like to present this question to the NA community. If you see resemblence to known algorithms or even have a reference please let me know or wirte directly to my collegue: His e-mail address is FM@DACTH51.BITNET Here comes the description of the algorithm. Assumption: x is an indeterminate and f(x)=x~n+a_(n-1)x~(n-1)+...+a_0 in R[x] is a real polynomial. Aim: Find a factorization f(x) = g(x)h(x). Framework: R[x]/f(x) denotes the ring of polynomials modulo f(x), whose elements are represented by the polynomials p(x) of degree less than n. The relation x~n=-(a_0+...+a_(n-1)x~(n-1)) is used to find this normal form e(p(x)) for p(x) in R[x] of degree greater or equal to n. Note, multiplication by x is represented by the companion matrix A of f(x) with respect to the basis 1,x,...,x~(n-1) of R[x]/f(x) and multiplication by p(x) by p(A)=:mat(p(x)). Algorithm:Choose a_0=p(x) in R[x]/f(x) with norm 1(= det(p(A))). Define a_(i+1):=a_i~2 ( multiplication in R[x]/f(x)). For moderately large n mat(a_n) will have k>0 eigenvalues close to zero and n-k>0 eigenvalues very big.(We neglect the case where p(A) has eigenvalues of absolute value 1.) Let z:=a_n. Test when z,xz,x~2z,... becomes (approximately) linearly dependent in R[x]/f(x) for the first time and obtain a relation x~kz=c_0z+c_1xz+...+c_(k-1)x~(k-1)z. Then g(x)=x~k-c_(k-1)x~(k-1)-...-c_0 in R[x] is a polynomial dividing f(x). Varying the degree of accuracy one might find different k's and divisors g(x) also with varying degree of accuracy from the same element z. --Rolf Jeltsch ------------------------------ From: UNCJWT%UNC.BITNET@Forsythe.Stanford.EDU Date: Mon, 19 Sep 88 16:40 EST Subject: Position in North Carolina UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL DEPARTMENT OF MATHEMATICS The Department of Mathematics at the University of North Carolina invites applications for a senior level tenured appointment in the general area of applied and/or computational mathematics. Rank and salary depend on qualifications; demonstrated excellence in research and teaching are required. Applications will be accepted until the position is filled; however, applications received by January 15,1989 are assured of full consideration. Inquiries should be directed to: Search Committee, % Pat Levin, Mathematics Department, CB# 3250, UNC at Chapel Hill, Chapel Hill, NC 27599. EO/AA employer. Women and minorities are encouraged to apply. ------------------------------ From: Alan J. Laub <laub%lanczos@hub.ucsb.edu> Date: Wed, 21 Sep 88 14:42:13 PDT Subject: Riccati Equation Meeting in Italy THE RICCATI EQUATION IN CONTROL, SIGNALS, AND SYSTEMS VILLA GALLIA, COMO (ITALY) -- JUNE 26-29, 1989 A WORKSHOP sponsored by C.N.R. -- Consiglio Nazionale delle Ricerche co-sponsored by I.F.A.C. -- International Federation of Automatic Control S.I.A.M. -- Society for Industrial and Applied Mathematics with the participation of the I.E.E.E. Control Systems Society ***** Politecnico di Milano Dipartimento di Elettronica and Centro di Teoria dei Sistemi C.N.R. PURPOSE OF THE MEETING: To present a coherent picture of the main results achieved in the last 30 years on the Riccati Equation. Theory, applications, and numerical algorithms will be considered with emphasis on its relevance to optimal control and filtering, Linear-Quadratic- Gaussian problems, H-infinity optimization, network synthesis, etc. There will be an opening lecture by R.E. Kalman -- Swiss Federal Institute of Technology, Zurich, Switzerland and Univer- sity of Florida, USA, three tutorial lectures (by A.J. Laub -- University of California, Santa Barbara, USA, M.A. Shayman -- University of Maryland, USA, and J.C. Willems -- University of Groningen, The Netherlands), invited lectures, and contributed papers. The language of the meeting is English. PROGRAM COMMITTEE: S. Bittanti -- Politecnico di Milano, Italy A.J. Laub -- University of California, Santa Barbara, U.S.A. J.C. Willems -- Groningen University, The Netherlands H.H. Wimmer -- Universitat Wurzburg, West Germany INVITED SPEAKERS: R.R. Bitmead -- Australian National University, Australia S. Bittanti -- Politecnico di Milano, Italy R.S. Bucy -- University of Southern California, USA R. Byers -- University of Kansas, USA A. Bunse-Gerstner -- Universitat Bielefeld, West Germany M. Gevers -- Universite Catholique Louvain, Belgium K. Glover -- Cambridge University, UK D. Hinrichsen -- Universitat Bremen, West Germany T. Kailath -- Stanford University, USA V. Kucera -- Czechoslovak Academy of Science, Czechoslovakia V. Mehrmann -- Universitat Bielefeld, West Germany J.B. Moore -- Australian National University, Australia T. Nishimura -- Institute of Space and Astronautical Science, Japan L. Rodman -- College of William and Mary, USA L.M. Silverman -- University of Southern California, USA J.L. Speyer -- University of Texas at Austin, USA H.L. Trentelman -- Technische Universiteit Eindhoven, The Netherlands J.L. Willems -- University of Ghent, Belgium H.H. Wimmer -- Universitat Wurzburg, West Germany CONTRIBUTED PAPERS: There is time allotted for high quality contributed papers. Only papers with original results will be accepted. Prospective au- thors are invited to submit 5 copies of an extended summary or draft manuscript in English to the Chairman at the following ad- dress: Professor S. Bittanti Dipartimento di Elettronica Politecnico di Milano Piazza Leonardo da Vinci 32 20133 Milano ITALY Telefax 2.23993587 Telex 333467 POLIMI-I The length of the draft should be approximately 5 double-spaced pages. Authors should also provide a title page, with a 350-word abstract, 5 keywords, full address, telephone or telefax number, and e-mail address if available. DEADLINES: November 30, 1988 5 copies of a 5 page extended summary or draft plus a title page to be mailed to the chairman February 28, 1989 Acceptance notification for contributed drafts April 30, 1989 Full manuscript due WORKSHOP LOCATION: The meeting will be held at Villa Gallia, an 18th Century villa located on the shore of Lake Como in Como, Italy. The historic town of Como is easily reachable from Milan either by car (motor- way A9) or train. Frequent trains start from Stazione Ferrovie Nord in Milan, but there are trains from the Stazione Centrale or Stazione Porta Garibaldi as well. Alternatively, Como can be reached from the Zurich airport by train or by car. ORGANIZING COMMITTEE: S. Bittanti -- Politecnico di Milano, Italy P. Bolzern -- Politecnico di Milano, Italy P. Colaneri -- Centro di Teoria dei Sistemi C.N.R., Italy C. De Nicolao -- Centro di Teoria dei Sistemi C.N.R., Italy In organizing the workshop, the organizers are being assisted by the Centro di Cultura Scientifica A. Volta, Villa Olmo (Como). The assistance of the Centro di Teoria dei Sistemi C.N.R., Mi- lano, and the Dipartimento di Elettronica del Politecnico di Mi- lano is also gratefully acknowledged. LOCAL ARRANGEMENTS: The Centro di Cultura Scientifica A. Volta will take care of the local organization, including hotel reservations. An early reservation is recommended since Como is already crowded with tourists in June. The address of the Centro is: Centro di Cultura Scientifica A. Volta Villa Olmo Via Cantoni 1 22100 Como ITALY Phone number: 31.552563 or 31.572213 Telex: 380547 CAM CO I Electronic mail: GCASATI@IMICLVX.BITNET ------------------------------ From: Baker Kearfott <rbk%usl.csnet@relay.cs.net> Date: Thu, 22 Sep 88 09:03:34 CDT Subject: Nineteenth Annual USL Mathematics Conference ANNOUNCEMENT NINETEENTH ANNUAL USL MATHEMATICS CONFERENCE OCTOBER 21 - 23, 1988 This year's weekend conference will be devoted to analysis (classical, applied, and numerical). We expect to follow the format of previous years, with colloquium type talks beginning Friday afternoon and ending early Sunday afternoon. We will also be inviting everyone to dinner Friday evening and to the shrimp boil on Saturday evening. A partial list of speakers is: John Cannon (Office of Naval Research) John Dennis (Rice University) Bill Fitzgibbon (University of Houston) Robin Forman (Rice University) Jerry Goldstein (Tulane University) Hans Kaper (Argonne National Labs.) Chen-Yuen Lin (Texas A&M University) Caruth McGehee (Louisiana State University) Jeff Morgan (Texas A&M University) John Polking (Rice University) Gizele Rieder (Louisiana State University) Ralph Saxton (University of New Orleans) Phil Smith (IMSL) Henry Warchall (University of North Texas) John Wolfson (Tulane University) You are welcome (RSVP). (However, there is no support other than for the two dinners.) For information, for comments or suggestions, or if you wish to make a presentation, please contact: Baker Kearfott (318) 231-5270 (Office) (318) 981-9744 (Home) kearfott%usl.csnet@relay.cs.net (EMAIL) or: Lloyd Roeling (318) 231-6545 (Office) (318) 988-0148 (Home) Mathematics Department (318) 231-6702 U. S. L. Box 4-1010 Lafayette, LA 70504 ------------------------------ From: MA37%primea.dundee.ac.uk@NSS.Cs.Ucl.AC.UK Date: Thu, 22 Sep 88 10:31:47 Subject: Dundee Biennial NA Conference 1989 13th BIENNIAL CONFERENCE ON NUMERICAL ANALYSIS UNIVERSITY OF DUNDEE, SCOLAND, UK 27-30 June 1989 Principal Speakers include M J Baines P Deuflhard T Lyche J H Bramble R Fletcher M J D Powell K Burrage I Graham A Ruhe T Coleman C Johnson A limited number of submitted papers will be presented. Full details of submission dates, conference fees, etc. will be available towards the end of 1988 and may be obtained by writing to either Dr D F Griffiths or Dr G A Watson: The Organizing Secretaries Biennial Conference on Numerical Analysis Department of Mathematics and Computer Science The University Dundee, DD1 4HN Scotland, UK Tel: 0382 23181 ext 4467/4474 e-mail:ma37@UK.AC.DUNDEE.PRIMEA ------------------------------ From: Gene Golub <golub@Patience.stanford.edu> Date: Fri, 23 Sep 88 15:50:43 PDT Subject: Position in OR at Stanford STANFORD UNIVERSITY Department of Operations Research The Department of Operations Research expects to have a tenure-track position, possibly joint with the Department of Computer Science, to be filled by September 1, 1989. We are soliciting applications from candidates in the areas of combinatorial optimization and numerical optimization. Candidates must have outstandinng research ability and potential. They must also be committed to excellence in teaching. The position requires the individual to teach on both the graduate and undergraduate levels, to carry out an active research program, and to provide research supervision for Ph.D. students. Candidates at both the junior and senior levels will be considered, although we have a preference for a younger scholar. Stanford is an equal opportunity/ affirmative action employer. Applications from women and minorities are especially welcome. Candidates should send a vita, the names of at least four references, and copies of selected publications (if any) to Prof. Donald L. Iglehart, Department of Operations Research, Terman Engineering Center, Stanford University, Stanford, CA 94305-4022. Further enquiries should be made to Professor Iglehart at 415/723-4094 or Iglehart@sierra.stanford.edu. ------------------------------ End of NA Digest ************************** ------- Reposted by -- Kenneth R. Jackson, krj@na.toronto.edu (on Internet, CSNet, Computer Science Dept., ARPAnet, BITNET) University of Toronto, krj@na.utoronto.ca (CDNnet and other Toronto, Canada M5S 1A4 X.400 nets (Europe)) (416) 978-7075