Randall Bramley Associate Professor Department of Computer Science Indiana University-Bloomington

The above image from the Emily matrix visualization package shows the inverse of the Laplace matrix on a uniform grid, with bright colors corresponding to larger magnitude elements. The pattern suggests possible sparsity patterns that can be effective for approximate inverse preconditioners.

[ Research Projects | Professional Affiliations | Selected Papers | Grants | Students | FTP directory]

My travel and event schedule is infrequently maintained, but the best explanation of any absences from the office.

Research Projects

The following links give brief descriptions of projects on which I am currently working; most of these are closely interrelated. Also see the Scientific Computing group home pages for lists of collaborators on these projects. A usage page showing hits for the SciComp material is created daily by AccessWatch.

• Parallel Computing
• Methods for large scale linear systems
• Stokes problems in computational fluid dynamics
• Row projection methods
• Partial orthogonalization preconditioners
• Domain decomposition
• Visualization
• Problem Solving Environments

Courses

A few courses of mine with some Web accessible content include

• B573: Introduction to Scientific Computing
• B673: Advanced Scientific Computing
• C343: Data Structures

Another educational project is the MATC (Mathematics Across the Curriculum) Project, where I am an informal consultant on the electronic dissemination and evaluation of curricular materials. Mathematics Throughout the Curriculum (MTC), the Indiana University component of MATC, is run by Dan Maki and Bart Ng. Brief talks I've given for that project include

Professional Affiliations

• ACM
• IEEE Computer Society
• Society for Industrial and Applied Mathematics (SIAM)

Some Recent or Interesting Papers

Most of these papers are gzipped Postscript format. Most browsers will simply download them as a file to your working directory, and then it is up to you to gunzip them and use a Postscript viewer from outside the browser.

• Simulation of 3-D Mold-filling and Solidification Processes on Distributed Memory Parallel Architectures by Florin Illinca, Jean-Francois Hetu, and Randall Bramley. In Proceedings of International Mechanical Engineering Congress and Exposition.
• Component Architectures for Distributed Scientific Problem Solving by D. Gannon, R. Bramley, T. Stuckey, J. Villacis, J. Balasubramanian, E. Akman, F. Breg, S. Diwan, and M. Govindaraju. Accepted for a special issue of IEEE CS&E.
• Parallel Preconditioners with Low Rank Off-Diagonal Blocks, R. Bramley and V. Menkov, submitted to Parallel Computing, 1996. An HTML version is also available.
• MPI Performance on the SGI Power Challenge, Tom Loos and R. Bramley, MPI Developers Conference, University of Notre Dame, July 1996
• A Necessary and Sufficient Condition for the Existence of Incomplete Cholesky Factorization, Under revision for IMACS.
• Partial Row Projection Methods, presented at the Colorado Conf on Iterative Methods, April 1996. A poorly done HTML version is also available here.
• Solving linear inequalities in a least squares sense, SIAM J. Sci. Comp 17(1996), pp. 275-286.
• CIMGS: A Incomplete Orthogonalization Preconditioner, SIAM J. Sci. Comp. 18(1997), pp. 516-536.
• An Orthogonal Projection Algorithm for Linear Stokes Problems, Technical Report.
• Combined Projection Algorithms for Generalized Stokes Problems, Working paper.
• Orthogonalization Based Iterative Methods for Generalized Stokes Problems, Book Chapter in Solution Techniques for Large--Scale CFD Problems, edited by W. G. Habashi, pp. 217--238.

My vita has a more complete list of papers.

Current Research Students

• Jayashree Balasubramanian
• Vladimir Menkov
• Thomas Stuckey

Some Former Research Students

• Gladimir Baranoski
• Chun-Perng Cheah
• John Groppe
• Yanlei He
• Younghee Lee
• Tom Loos
• Etsuko Mizukama
• Deepa Viswanathan
• Geetha Ravishankar
• Nathaniel Reed
• Janet Spoonamore

Current Grants Providing Support

Other stuff

Peter Shirley created a useful Postscript map of how to get from the Indianapolis Airport to Bloomington. Visitors are strongly recommended not to fly into Bloomington, since Indianapolis is only 1.0 - 1.25 hours drive from here.

Ok, if you really want to see what I look like in my native environment a picture of me is available. And you can also see a picture of Radha Surya (my wife, among other things) shortly before we got married.