Send mail to: mgnet@cs.yale.edu for the digests or bakeoff mgnet-requests@cs.yale.edu for comments or help Current editor: Craig Douglas douglas-craig@cs.yale.edu Anonymous ftp repository: casper.cs.yale.edu (128.36.12.1) ftp.cerfacs.fr (138.63.200.33) World Wide Web: http://na.cs.yale.edu/mgnet/www/mgnet.html or http://www.cerfacs.fr/~douglas/mgnet.html Today's editor: Craig Douglas (douglas-craig@cs.yale.edu) Volume 6, Number 6 (approximately June 30, 1996) Today's topics: Web pages are getting a new look Papers by Doug Arnold et al Bibliography search engine for web browsing through mgnet.bib? MGNet Database Bibliography Corrections and Additions Some of the new entries in the bibliography Workshop on Scientific Computing 97 Job Postings ------------------------------------------------------- Date: Sun, 30 Jun 1996 14:17:32 -0500 From: Craig DouglasSubject: Web pages are getting a new look When MGNet started there was anonymous ftp and e-mail. Now I am sure that virtually all of you who access MGNet directly use a web browser. I am updating the information in MGNet to be more web friendly. The main page, the papers' page, and the old digests' pages have been updated. Having a browser that can handle netscape extensions to html is useful (e.g., tables). Getting a search device into the bibliography page would be a help (see a related request later in this issue). There are now a number of hyperlinks on the main page to other, related web pages. If you think that an addition is needed or have a suggestion of how to better organize this, please send me e-mail. One of the standard ways people contribute a large object is by ftp to a (formerly) world writable directory on casper.cs.yale.edu. Due to a large volume of zip files containing commercial products that has been coming through this directory recently, I have changed the file protections. If you need to ftp files to casper, please contact me by e-mail first. When the people quit trying to put files on the machine, the protections may change back. I have found it fairly painless lately to get a URL from someone and fetch the files myself. ------------------------------------------------------- Date: Fri, 31 May 1996 12:12:49 -0500 From: Douglas Arnold Subject: Papers by Doug Arnold et al Preconditioning in H(div) and Applications by Douglas N. Arnold, Richard S. Falk, and Ragnar Winther To appear in Math. Comp. 66 (1997) ABSTRACT: We consider the solution of the system of linear algebraic equations which arises from the finite element discretization of boundary value problems associated to the differential operator I - grad div. The natural setting for such problems is in the Hilbert space H(div) and the variational formulation is based on the inner product in H(div). We show how to construct preconditioners for these equations using both domain decomposition and multigrid techniques. These preconditioners are shown to be spectrally equivalent to the inverse of the operator. As a consequence, they may be used to precondition iterative methods so that any given error reduction may be achieved in a finite number of iterations, with the number independent of the mesh discretization. We describe applications of these results to the efficient solution of mixed and least squares finite element approximations of elliptic boundary value problems. * * * * * * * * * * * * * * * * * * * * Preconditioning discrete approximations of the Reissner-Mindlin plate model by Douglas N. Arnold, Richard S. Falk, and Ragnar Winther To appear in Mathematical Modelling and Numerical Analysis 31 (1997) ABSTRACT: We consider iterative methods for the solution of the linear system of equations arising from the mixed finite element discretization of the Reissner-Mindlin plate model. We show how to construct a symmetric positive definite block diagonal preconditioner such that the resulting linear system has spectral condition number independent of both the mesh size h$ and the plate thickness h. We further discuss how this preconditioner may be implemented and then apply it to efficiently solve this indefinite linear system. Although the mixed formulation of the Reissner-Mindlin problem has a saddle-point structure common to other mixed variational problems, the presence of the small parameter t and the fact that the matrix in the upper left corner of the partition is only positive semidefinite introduces new complications. * * * * * * * * * * * * * * * * * * * * Analysis of a linear-linear finite element for the Reissner-Mindlin plate model by Douglas N. Arnold and Richard S. Falk To appear in Math. Models and Methods in Appl. Sci. 7 (1997) ABSTRACT: An analysis is presented for a recently proposed finite element method for the Reissner-Mindlin plate problem. The method is based on the standard variational principle, uses nonconforming linear elements to approximate the rotations and conforming linear elements to approximate the transverse displacements, and avoids the usual "locking problem" by interpolating the shear stress into a rotated space of lowest order Raviart-Thomas elements. When the plate thickness t=O(h), it is proved that the method gives optimal order error estimates uniform in t. However, the analysis suggests and numerical calculations confirm that the method can produce poor approximations for moderate sized values of the plate thickness. Indeed, for t fixed, the method does not converge as the mesh size h tends to zero. * * * * * * * * * * * * * * * * * * * * Interior estimates for a low order finite element method for the Reissner-Mindlin plate by Douglas N. Arnold and Xiaobo Liu ABSTRACT: Interior error estimates are obtained for a low order finite element introduced by Arnold and Falk for the Reissner-Mindlin plates. It is proved that the approximation error of the finite element solution in the interior domain is bounded above by two parts: one measures the local approximability of the exact solution by the finite element space and the other the global approximability of the finite element method. As an application, we show that for the soft simply supported plate, the Arnold-Falk element still achieves an almost optimal convergence rate in the energy norm away from the boundary layer, even though optimal order convergence cannot hold globally due to the boundary layer. Numerical results are given which support our conclusion. Editor's Note: All four papers are available directly from the math dept. ------------- web server at Penn State: http://www.math.psu.edu/dna/publications.html or through the MGNet papers web page. ------------------------------------------------------- Date: Fri, 28 Jun 1996 09:33:03 PDT From: Feng Zhao Subject: Bibliography search engine for web browsing through mgnet.bib? I'd like to know if there is an online version of the Multigrid bibliography. Editor's Note: In a sense there is an online version. The world ------------- bibliography in Germany keeps an up to date version that can be searched through the web. I have been promised several times a perl script that would search my list from the web, but nobody has ever sent me such a script. Scripts to do this clearly already exist. Pointers to one or a donation of one would be highly appreciated. ------------------------------------------------------- Date: Sun, 16 Jun 96 21:23:20 METDST From: david dureisseix Subject: MGNet Database As I was verifying my own bibliographic bibtex files, I looked at mgnet.bib which efficiently helped me. Nevertheless, it seems to me that I have found some little bugs in this file... If fixing them can help, here is a little compilation of what I have found ... Editor's Note: A lot of corrections were made as a result of this message ------------- and another one later. If you are using the bibliography, you should definitely download a new copy. I have eventually also additions to submit to the database, all of them are related to domain decomposition. Here they are: Editor's Note: I put these into a later message. ------------- ------------------------------------------------------- Date: Mon, 10 Jun 1996 15:56:59 +0200 From: Thor Gjesdal Subject: Bibliography Corrections and Additions I spotted the following two typos (SHOCK! HORROR!! :-) in mgnet.bib (version of Feb 21, 1996)... a related paper to this last one is the following which doesn't seem to be in there yet is... Editor's Note: I put the new one into the next message. ------------- ------------------------------------------------------- Date: Mon, 01 Jul 1996 14:16:40 -0500 From: Craig Douglas Subject: Some of the new entries in the bibliography Here are some recent new entries. As usual, please send additions and corrections. The most recently posted bibliography is dated July 1, 1996. REFERENCES [1] G. Agrawal, A. Sussman, and J. H. Saltz, An integrated runtime and compile time approach for parallelizing struc- tured and block structured applications, IEEE Trans. Parallel Distrib. Syst., 6 (1995), pp. 747-754. [2] M. Al-Nasra and D. T. Nguyen, An algorithm for domain decomposition in finite element analysis, Comput. Struct., 39 (1991), pp. 277-289. [3] A. A. Ameri and E. Steinthorsson, Prediction of un- shrouded rotor blade tip heat transfer, in Proceedings of the International Gas Turbine and Aeroengine Congress and Ex- position, vol. 95-GT-142, New York, 1995, American Society of Mechanical Engineers, p. 9. [4] L. Angermann, Balanced a posteriori error estimates for finite-volume type discretizations of convection-dominated elliptic problems, Computing, 55 (1995), pp. 305-323. [5] A. Arnone and R. Pacciani, Rotor-stator interaction anal- ysis using the Navier-Stokes equations and a multigrid method, in Proceedings of the International Gas Turbine and Aeroengine Congress and Exposition, vol. 95-GT-177, New York, 1995, American Society of Mechanical Engineers, p. 15. [6] A. Averbuch, M. Israeli, and L. Vozovoi, Paral- lel implementation of non linear evolution problems us- ing parabolic domain decomposition, Parallel Comput., 21 (1995), pp. 1151-1183. [7] M. Baeker, ISU - multigrid for computing propagators, Nucl. Phys. B, Proc. Suppl., 42 (1995), pp. 846-848. [8] R. E. Bank and D. J. Rose, Some error estimates for the box scheme, SIAM J. Numer. Anal., 24 (1987), pp. 777-787. [9] R. Becker, C. Johnson, and R. Rannacher, Adaptive er- ror control for multigrid finite element methods, Computing, 55 (1995), pp. 271-288. [10] J. Bey, Tetrahedral grid refinement, Computing, 55 (1995), pp. 355-378. [11] D. Braess, Towards algebraic multigrid for elliptic problems of second order, Computing, 55 (1995), pp. 379-393. [12] L. Champaney, J.-Y. Cognard, D. Dureisseix, and P. Ladev`eze, 3D structures assembly analysis with a mod- ular approach suited to parallel computations, in 28th In- ternational Symposium on Automotive Technology and Au- tomation, Stuttgart, 1995, pp. 285-292. [13] T. F. Chan and J. P. Shao, Parallel complexity of domain decomposition methods and optimal coarse grid size, Parallel Comput., 21 (1995), pp. 1033-1049. [14] J.-Y. Cognard, D. Dureisseix, P. Ladev`eze, and Ph. Lorong, Exp'erimentation d'une approche parall`ele en cal- cul de structures, Rev. Europ. 'El'ements Finis, 5 (1996), pp. 197-220. [15] W. Dahmen, A. Kunoth, and K. Urban, A wavelet Galerkin method for the Stokes equations, Computing, 56 (1996), pp. 259-302. [16] P. M. de Zeeuw, Development of semi-coarsening techniques, Appl. Numer. Math., 19 (1996), pp. 433-465. [17] T. F. Doniere and A. P. Dhawan, A transition criterion for the multigrid expectation maximization reconstruction algo- rithm for positron emission tomography, in Proceedings of the 16th Annual International Conference of the IEEE En- gineering in Medicine and Biology Society. Engineering Ad- vances: New Opportunities for Biomedical Engineers, New York, 1994, IEEE, pp. 630-631. [18] W. D"orfler, A robust adaptive strategy for the non-linear Poisson equation, Computing, 55 (1995), pp. 289-304. [19] T. Dornseifer and C. Pflaum, Discretization of elliptic differential equations on curvilinear bounded domains with sparse grids, Computing, 56 (1996), pp. 197-213. [20] C. Farhat, S. Lanteri, and H. D. Simon, TOP/DOMDEC a software tool for mesh partitioning and parallel processing, Comput. Syst. Eng., 6 (1995), pp. 13-26. [21] S. Ghosal and P. Van~ek, A fast scalable algorithm for discon- tinuous optical flow estimation, IEEE Trans. Pattern Anal. Mach. Intell., 18 (1996), pp. 181-195. [22] F. Grasso and M. Marini, Solutions of hypersonic viscous flows with total variation diminishing multigrid techniques, Comput. Fluids, 24 (1995), pp. 571-592. [23] B. Heise and M. Kuhn, Parallel sovers for linear and nonlin- ear exterior magnetic field problems based on coupled FE/BE formulations, Computing, 56 (1996), pp. 237-258. [24] G. Horton and S. Vandewalle, A space time multigrid method for parabolic partial differential equations, SIAM J. Sci. Comput., 16 (1995), pp. 848-864. [25] Y.-S. Hwang, R. Das, and J. H. Saltz, Parallelizing molec- ular dynamics programs for distributed-memory machines, IEEE Comput. Sci. Eng., 2 (1995), pp. 18-29. [26] K. A. Iyer, M. P. Merrick, and T. L. Beck, Application of a distributed nucleus approximation in grid based minimiza- tion of the Kohn Sham energy functional, J. Chem. Phys., 103 (1995), pp. 227-233. [27] W. Janke and T. Sauer, Monte Carlo simulation of 1+1- dimensional OE4 quantum field theory, Nucl. Phys. B, Proc. Suppl., 42 (1995), pp. 917-919. [28] P. Johansson and L. Davidson, Modified collocated SIM- PLEC algorithm applied to buoyancy affected turbulent flow using a multigrid solution procedure, Numer. Heat Transf. B, Fundam., 28 (1995), pp. 39-57. [29] T. Kalkreuter, Spectrum of the Dirac operator and inversion algorithms with dynamical staggered fermions, Nucl. Phys. B, Proc. Suppl., 42 (1995), pp. 882-884. [30] P. Ladev`eze and Ph. Lorong, A large time increment ap- proach with domain decomposition technique for mechanical non linear problems, in Proceedings of the 10th International Conference on Computing Methods in Applied Sciences and Engineering, R. Glowinski, ed., New York, 1992, Nova Sci- ence Publishers, pp. 569-578. [31] S. Larsson, V. Thomee, and S. Z. Zhou, On multi- grid methods for parabolic problems, J. Comput. Math., 13 (1995), pp. 193-205. [32] C. O. Lee and S. V. Parter, On the rate of convergence of the k *k block, k line iterative methods: k to infinity, Numer. Math., 71 (1995), pp. 59-90. [33] P. Leinen, Data structures and concepts for adaptive finite el- ement methods, Computing, 55 (1995), pp. 325-354. [34] P. LeTallec, J. Mandel, and M. Vidrascu, Balancing do- main decomposition for plates, in Domain Decomposition Methods in Scientific and Engineering Computing: Proceed- ings of the Seventh International Conference on Domain De- composition, vol. 180 of Contemporary Mathematics, Provi- dence, Rhode Island, 1994, American Mathematical Society, pp. 515-524. [35] C. Liu and Z. Liu, Multigrid mapping and box relaxation for simulation of the whole process of flow transition in 3D boundary layers, J. Comput. Phys., 119 (1995), pp. 325-341. [36] C. A. Long, A. P. Morsecand, and P. G. Tucker, Mea- surement and computation of heat transfer in high pressure compressor drum geometries with axial throughflow, in Pro- ceedings of the International Gas Turbine and Aeroengine Congress and Exposition, vol. 95-GT-185, New York, 1995, American Society of Mechanical Engineers, p. 16. [37] D. J. Mavriplis and V. Venkatakrishnan, Agglomeration multigrid for two dimensional viscous flows, Comput. Fluids, 24 (1995), pp. 553-570. [38] M. R. Mehrabi and R. A. Brown, Parallel implementation of finite-element/Newton method for solution of steady-state and transient nonlinear partial differential equations, J. Sci. Comput., 10 (1995), pp. 93-137. [39] R. Merz, K. Joerg, J. F. Mayer, and H. Stetter, Com- putation of three-dimensional viscous transonic turbine stage flow including TIP clearance effects, in Proceedings of the International Gas Turbine and Aeroengine Congress and Ex- position, vol. 95-GT-76, New York, 1995, American Society of Mechanical Engineers, p. 8. [40] J. Molenaar, Multigrid for semiconductor device simulation: cell-centered or vertex-centered multigrid?, Math. Eng. In- dustry, 5 (1995), pp. 1-22. [41] R. P. Nance, R. G. Wilmoth, B. Moon, H. A. Has- san, and J. H. Saltz, Parallel Monte Carlo simulation of three-dimensional flow over a flat plate, J. Thermophys. Heat Trans., 9 (1995), pp. 471-477. [42] T. Oshima, S. Nagata, and H. Ishikawa, Acceleration of computational fluid dynamics by parallel asynchronized iter- ative algorithms (an evaluation of speed-up for point SOR method), Trans. Japan Soc. Mech. Eng., Part B, 61 (1995), pp. 1368-1373. [43] P. D. Panagiotopoulos and M. A. Tzaferopoulos, On the numerical treatment of nonconvex energy problems: Mul- tilevel decomposition methods for hemivariational inequali- ties, Comput. Meth. Appl. Mech. Eng., 123 (1995), pp. 81- 94. [44] P. Ramanathan and S. Chalasani, Parallel multigrid al- gorithms on CM-5, in Computers and Digital Techniques, vol. 142 of IEEE Proceedings, New York, 1995, IEEE, pp. 177-184. [45] A. Reusken, On a robust multigrid solver, Computing, 56 (1996), pp. 303-322. [46] P. J. Roache, The SECOsuite of codes for site performance as- sessment, in Proceedings of the Fourth Annual International Conference on High Level Radioactive Waste Management, vol. 2, New York, 1993, American Society of Civil Engineers, pp. 1586-1594. [47] Y.-H. de Roeck, P. LeTallec, and M. Vidrascu, A domain decomposed solver for nonlinear elasticity, Comp. Meth. Appl. Mech. Engng., (1992), pp. 187-207. [48] I. G. Rosen and W. Chunming, A multilevel technique for the approximate solution of operator Lyapunov and alge- braic Riccati equations, SIAM J. Numer. Anal., 32 (1995), pp. 514-541. [49] G. J. Shaw and S. Sivaloganathan, On the smoothing prop- erties of the SIMPLE pressure-correction algorithm, Int. J. Numer. Meth. Fluids, 8 (1988), pp. 441-461. [50] D. Sidilkover and U. M. Ascher, A multigrid solver for the steady state Navier Stokes equations using the pressure Pois- son formulation, Comput. Appl. Math., 14 (1995), pp. 21-35. [51] A. S. da Silva, T'ecnica de multi-grid aplicada ao m'etodo dos elementos finitos, Master's thesis, Campo Montenegro, S"ao Jos'e dos Campos, SP, Brazil, 1990. [52] C. Su, Domain decomposition method for determining the diffu- sion coefficient of a two-dimensional linear diffusion equa- tion in the time domain, Appl. Numer. Math., 15 (1994), pp. 481-493. [53] M. D. Tidriri, Domain decomposition for compressible Navier Stokes equations with different discretizations and formula- tions, J. Comput. Phys., 119 (1995), pp. 271-282. [54] M. Tummala and D. A. Richter, Iterative system modeling using multigrid techniques, in 1993 IEEE International Sym- posium on Circuits and Systems, vol. 4 of IEEE Proceedings, New York, 1993, IEEE, pp. 2525-2528. [55] P. Van~ek and S. Ghosal, A new technique for construction of image pyramids, Asian Conference on Computer Vision, 1 (1996), pp. 479-483. [56] P. Van~ek, J. Mandel, and M. Brezina, Algebraic multigrid based on smoothed aggregation for second and fourth order problems, Computing, 56 (1996), pp. 179-196. [57] J. S. Volk, Analysis of multigrid techniques for system model- ing with toeplitz approximation, Master's thesis, Naval Post- graduate School, Monterey, CA, 1994. [58] J. Xu, The auxiliary space method and optimal multigrid pre- conditioning techniques for unstructured meshes, Comput- ing, 56 (1996), pp. 215-235. [59] L. Y. Zaslavsky, An adaptive algebraic multigrid for reactor criticality calculations, SIAM J. Sci. Comput., 16 (1995), pp. 840-847. ------------------------------------------------------- Date: Mon, 1 Jul 1996 12:03:46 +0800 (EAT) From: "Dr. Raymond Chan" Subject: Workshop on Scientific Computing 97 Workshop on Scientific Computing 97 Hong Kong March 10-12, 1997 First Announcement and Call for Paper OBJECTIVE: This three-day workshop is the sequel to the series of workshops on Scientific Computing that were held in Hong Kong in the past few years. It aims to promote research interest in scientific computation for local mathematicians and engineers and to foster contacts and exchanges with experts from other parts of the world. This year the workshop will feature a special session on modern methods in scientific computing relevant to digital signal and image processing. WORKSHOP THEMES: Numerical linear algebra, Signal and image processing, Optimization, Least square, CAGD, Control, and Statistical computing. KEY-NOTE SPEAKER: Gene Golub (Stanford University, USA) INVITED SPEAKERS: Richard Bartels (University of Waterloo, Canada) Ake Bjorck (Linkoping University, Sweden) Daniel Boley (University of Minnesota, USA) Richard Brent (Australian National University, Australia) Da-yong Cai (Tsinghua University, China) Tony Chan (UCLA, USA) Walter Gander (ETH Zuerich, Switerzland) Frank Luk (Rensselaer Polytechnic Institute, USA) Roy Pike (London University, UK) Robert Plemmons (Wake Forest University, USA) Michael Saunders (Stanford University, USA) Werner Stuetzle (University of Washington, USA) Ji-gunng Sun (Umea University, Sweden) Paul Vandooren (U. Catholique de Louvain, Belgium) Curtis Vogel (Montana State University, USA) LOCAL ORGANIZING COMMITTEE: Lester Liu, City University of Hong Kong Shiu-hong Lui, Hong Kong University of Science & Technology Tsi-min Shih, Hong Kong Polytechnic University Tao Tang, Chinese University of Hong Kong Chong Sze Tong, Hong Kong Baptist University Wei-min Xue (Chairman), Hong Kong Baptist University Siu-pang Yun, University of Hong Kong PROGRAM COMMITTEE: Raymond Chan (Chinese University of Hong Kong) Frank Luk (Rensselaer Polytechnic Institute, USA) Robert Plemmons (Wake Forest University, USA) Abstracts of contributed papers should be sent by Oct. 15, 1996 to: Dr. Wei-min Xue Dept. of Mathematics Hong Kong Baptist University 224 Waterloo Rd, Kowloon Tong, Hong Kong E-mail: wsc97@sci.hkbu.edu.hk WORKSHOP SCHEDULE: Oct. 15, 96 Deadline for submitting abstract, Nov. 30, 96 Deadline for submitting full paper, Dec. 31, 96 Notification of acceptance, Jan. 10, 97 Deadline for early registration, Feb. 10, 97 2nd announcement. ORGANIZED AND SPONSORED BY: Dept. of Math., Chinese University of Hong Kong Dept. of Math., City University of Hong Kong Dept. of Math., Hong Kong Baptist University Dept. of Math., Hong Kong University of Science & Technology Dept. of Appl. Math., Polytechnic University of Hong Kong Dept. of Math., University of Hong Kong SPECIAL EVENT: There will be a banquet on March 12, 1997 to celebrate the 65th birthday of Professor Gene Golub. REGISTRATION: Registration form can be obtained from Dr. W.M. Xue (address above) or via internet at http://www.math.hkbu.edu.hk/wsc/reg97.html. FURTHER INFORMATION: WSC97: http://www.math.hkbu.edu.hk/wsc/wsc97.html Hotel: http://www.ims.cuhk.edu.hk THE CITY OF HONG KONG: The territory of Hong Kong covers approximately 1,000 square kilometers and comprises of Hong Kong island, the Kowloon Peninsula, the New Territories, and around 400 outlying islands. It has a population of more than six million people, 98%of whom are Chinese. In March, the weather is mild, sunny and with average temperature ranging from 10C to 20C. The year 1997 is a historical landmark for Hong Kong, as it approaches the imminent return to China. Come and feel the excitement in this dynamic city. ------------------------------------------------------- Date: Mon, 24 Jun 1996 10:58:16 -0700 From: "Daniel L. Marcus" Subject: Job Postings Please post the following job announcements to mgnet Thank you Daniel Marcus Center for Computational Sciences and Engineering, LBNL MS 50D-117, 1 Cyclotron Road Berkeley, CA 94720 Phone: (510)486-5124, Fax: (510)486-6900 POST-DOC POSITIONS AVAILABLE Center for Computational Sciences and Engineering (CCSE) Lawrence Berkeley National Laboratory Berkeley, California The Center for Computational Sciences and Engineering has a number of positions available for post-doctoral researchers or visiting scientists. These are full-time, one-year-term appointments with the possibility of renewal. The mission of CCSE is to develop and apply advanced computational methodologies to solve large-scale scientific and engineering problems. The methodology used by CCSE centers around the development and use of adaptive high-resolution finite-difference methods for fluid dynamics and composite grid or embedded boundary representations of engineering geometries. Application areas include atmospheric flows, low speed reacting flows, and compressible flows. The successful candidate will participate in an on-going research effort in one of the above areas. There are also positions available for developing software infrastructure to support our numerical methodology. These include an opening for someone experienced in numerical linear algebra, particularly iterative solvers, to extend existing adaptive grid multigrid libraries, and someone to implement parallel versions of our methodology for the Cray T3E at NERSC. All positions require significant programming and technical interaction with other members of CCSE. The successful applicant must be able to work with and extend existing software and develop reliable and readable code. Throughout the project, the appointee should be able to investigate issues of algorithmic design as well as validate the resulting software by comparison with available data. She or he will also be expected to prepare results for publication in scientific journals and for presentations tions at national meetings. Requirements for these positions are: * working knowledge of C++ and FORTRAN, * Ph.D. within the last four years in applied mathematics, engineering, computer science, or related field (for post-doc positions only) Familiarity with modeling low Mach number flows a plus. Experience in parallel computing a plus. If interested, please contact John Bell at jbbell@lbl.gov. * * * * * * * * * * * * * * * * * * * * PROGRAMMER POSITIONS AVAILABLE Center for Computational Sciences and Engineering (CCSE) Lawrence Berkeley National Laboratory Berkeley, California The Center for Computational Sciences and Engineering has a number of positions available for scientific programmers. These are full-time, career appointments. The mission of CCSE is to develop and apply advanced computational methodologies to solve large-scale scientific and engineering problems. The methodology used by CCSE centers around the development and use of adaptive high-resolution finite-difference methods for fluid dynamics and composite grid or embedded boundary representations of engineering geometries. We are seeking candidates to participate in the following projects: * development of an interface between CAD/CAM descriptions of engineering geometries and CCSE's fluid dynamic simulation programs. * development of interfaces between CCSE's fluid dynamics codes and complex physics packages such as chemical databases for reaction rates and thermodynamic properties for modeling reacting flows * development of data structures and C++ class libraries to support the implementation of CCSE's adaptive methodology * development of a parallel processing software layer for C++ libraries that supports adaptive computations in fluid dynamics. The successful applicant in each case will be part of a team engaged in implementing and releasing high-performance fluid dynamic simulators and visualization software. These positions require programming and technical interaction with other members of CCSE and vendors. Requirements for these positions are: * Experience with object-oriented programming and C++ * B.A., B.S., or M.S. in computer science, mathematics or engineering, or equivalent experience. Background in scientific programming and algorithm implementation would be a plus. Experience on Cray supercomputers and high- performance DEC alpha workstations is a plus. If interested, please contact John Bell at jbbell@lbl.gov. ------------------------------ End of MGNet Digest **************************