Van Emden Henson

Center for Applied Scientific Computing, L-560

Lawrence Livermore National Laboratory

Livermore, CA 94551

Phone: (925) 423-4283
Fax: (925) 422-6287
E-mail: vhenson@llnl.gov

Research Interests

Algebraic Multigrid
Multigrid methods
Iterative Solvers
Numerical PDEs
Geophysics

Education

Ph.D. Applied Mathematics, University of Colorado at Denver, 1990

M.S. Applied Mathematics, University of Colorado at Denver, 1988

B.S. Geophysics, University of Utah, 1979

B.S. Geology, University of Utah, 1979

Professional Experience

1999- Numerical Methods Group Leader, Center for Applied Scientific Computing, LLNL

1997-1999 Applied Mathematician, Center for Applied Scientific Computing, LLNL

1991-1997 Assistant Professor of Mathematics, Naval Postgraduate School, Monterey, CA

1987-1990 Research Assistant & Teaching Assistant, Department of Mathematics, University of Colorado at Denver

1984-1987 Exploration Geophysicist, Occidental Petroleum, Denver, CO

1979-1984 Exploration Geophysicist, Cities Service Oil and Gas Corporation, Denver, CO

Honors and Organizations

Outstanding Research Achievement, Naval Postgraduate School, 1994
Outstanding Instructional Performance, Naval Postgraduate School, 1993
Outstanding Graduate Student, College of Liberal Arts and Sciences, University of Colorado, 1991
Winner of Student Paper Competition, Second International Conference on Vector and Supercomputing, Tromsø, Norway, June 1988, for the paper, "Parallel Compact Symmetric FFTs."
Magna Cum Laude, University of Utah, 1979
Phi Beta Kappa and Phi Kappa Phi, University of Utah, 1979
SIAM, MAA

Selected Publications and Presentations

Books

Briggs, W.L., Henson, V.E., and McCormick, S.F., A Multigrid Tutorial, 2^nd Edition, Society of Industrial and Applied Mathematics, Philadelphia, PA, 200 pages, to appear, Spring, 2000.

Briggs,W.L., and Henson, V.E., The DFT: an owner's manual for the discrete Fourier transform, Society of Industrial and Applied Mathematics, Philadelphia, PA, 434 pages, 1995.

Book Chapters

Cleary, A., R. Falgout, V. Henson, and J. Jones, "Coarse-Grid Selection for Parallel Algebraic Multigrid," Proceedings of the Fifth International Symposium on Solving Irregularly Structured Problems in Parallel, Springer-Verlag Lecture Notes in Computer Science, New York, August 1998. Held at Lawrence Berkeley National Laboratory, Berkeley, CA, August 9û11, 1998. Also available as Lawrence Livermore National Laboratory technical report UCRL-JC-130893.

Refereed Publications

Cleary, A., R.D. Falgout, V.E. Henson, J.E. Jones, T.A. Manteuffel, S.F. McCormick, G.N. Miranda, and J. Ruge, "Robustness and Scalability of Algebraic Multigrid," to appear in SIAM Journal of Scientific Computation . Also available as Lawrence Livermore National Laboratory technical report UCRL-JC-130718.

Brezina, M., A. Cleary, R.D. Falgout, V.E. Henson, J.E. Jones, T.A. Manteuffel, S.F. McCormick, and J. Ruge, "Algebraic Multigrid Based on Element Interpolation (AMGe)," to appear in SIAM Journal of Scientific Computation. Also available as Lawrence Livermore National Laboratory technical report UCRL-JC-131752.

Henson, V.E., and A.W. Shaker, "Theory and Numerics for a Semilinear Elliptic PDE, with an Application in the Theory of Pseudoplastic Fluids," Applicable Analysis, 63, pp. 271û285, 1996.

Briggs, W.L., and Henson, V.E., "A Table of Analytical Discrete Fourier Transforms, Applied Numerical Mathematics, 20, pp. 1û10, 1996.

Henson, V.E., M.A. Limber, S.F. McCormick, and B.T. Robinson, "Multilevel image reconstruction with natural pixels," SIAM J. Sci. Comp, 17, No. 1, pp. 193û216, 1996.

Briggs, W.L., and V.E. Henson, "Wavelets and Multigrid," SIAM J. Stat. & Sci. Comp., 14 No. 2, pp. 506û10, March 1993.

Swarztrauber, R.A. Sweet, W.L. Briggs, V.E. Henson and J. Otto, "Bluestein's FFT for Arbitrary N on the Hypercube," Parallel Computing, 17, pp. 607û17, 1991.

Briggs, W.L., and V.E. Henson, "The FFT as a Multigrid Algorithm," SIAM Review, 32, No. 2, pp. 252û61, June 1990.

Henson, V.E., "Parallel Compact Symmetric FFTs," in Vector and Parallel Computing Issues in Applied Research and Development, Dongarra, Duff, Gaffney, and McKee, eds., John Wiley and Sons, New York, N.Y., pp. 153û64, 1989.

Published Conference Proceedings

Canright, D., and V.E. Henson, "An FVE-FAC approach to determining thermocapillary effects on weldpool shape," in Proc. 7th Copper Mountain Conference on Multigrid Methods, NASA Conference Publications CP-3339, pp. 147û66, 1996.

Henson, V.E., and A. Shaker, "Multigrid Solution of a Singular Nonlinear BVP in Fluid Theory," in Proc. First Asian CFD Conference, 2, pp. 791û96, Hong Kong University of Science and Technology, 1995.

Henson, V.E., M.A. Limber, S.F. McCormick, B.T. Robinson, "Spotlight Computed Tomography with Natural Pixels," in Proc. Fifth SIAM Conference on Applied Linear Algebra, pp. 97û101, 1994.

Henson, V.E., and A. Shaker, "Multigrid Methods for a Semilinear PDE in the Theory of Pseudoplastic Fluids", Proc. Copper Mountain Conference on Multigrid Methods, NASA Conference Publications, CP-3224, pp. 231û42, 1993.

Henson, V.E., and K.J. Cavanaugh, "A Multilevel Cost-Space Approach to Solving the Long Balanced Transportation Problem," Proc. Copper Mountain Conference on Multigrid Methods, NASA Conference Publications, CP-3224, pp 61û76, 1993.

Briggs, W.L., and V.E. Henson, "Wavelets and Multigrid," Proc. IMACS First International Conference on Computational Physics," Boulder, CO, June 1990.

Briggs, W.L., and V.E. Henson, "A Shared Memory Parallel FFT for Real and Even Sequences," Transactions of the 6th Army Conference on Applied Mathematics and Computing, ARO Report 89û1, pp. 733û48, 1989.

Technical Reports

Henson, V.E., "DFTs on Irregular Grids: the Anterpolated DFT," NPS Research Report Number NPS-MA-92-006, March 1992.

W.L. Briggs, and V.E. Henson, "A Table of Analytical Discrete Fourier Transforms," Center for Computational Mathematics Report Number 30, University of Colorado at Denver, 1995

Invited Conference Presentations

Henson, V.E., "BoomerAMG: Advances in parallelizing algebraic multigrid," 4^th International Congress for Industrial and Applied Mathematics, Edinburgh, Scotland, July, 1999.

Henson, V.E., "An Algebraic Multigrid Tutorial," 9^th Copper Mountain Conference on Multigrid Methods, Copper Mountain, Colorado, April, 1999.

Henson, V.E., R.D. Falgout, J.E. Jones, U.M. Yang, "BoomerAMG: A Parallel Implementation of Algebraic Multigrid", 9^th SIAM Conference on Parallel Computing, San Antonio, Texas, March 1999.

Henson, V.E., "Multigrid Methods for Solving PDEs Numerically: an Overview," Joint Annual Meetings of the American Physics Society and the American Association of Physics Teachers, Columbus, Ohio, April, 1998

Conference Presentations

Henson, V.E., R.D. Falgout, J.E. Jones, U.M. Yang, "Some Recent Advances in Algebraic Multigrid," 10^th International GAMM Workshop on Multigrid Methods, Bonn, Germany, October, 1998.

Henson, V.E., A. Cleary, R.D. Falgout, J.E. Jones, "Parallel Algebraic Multigrid: A Prototype," 5^th Copper Mountain Conference on Multigrid Methods, Copper Mountain, Colorado, April, 1998.

Henson, V.E., "Algebraic Multigrid! What, How, and Why," 5^th Copper Mountain Conference on Iterative Methods, Copper Mountain, Colorado, April, 1998.

Henson, V.E., "CASC Linear Solvers: Multigrid Methods for ASCI Applicatiions," ASCI Principal Investigators Meeting, Snowbird, Utah, October 1997.

Henson, V.E., and R.D. Falgout, "Towards a Fully Parallelizable Algebraic Multigrid," 8th Copper Mountain Conference on Multigrid Methods, April 1997.

Henson, V.E., "Image Reconstruction from Projections using Adjoint Interpolation," 4^th Copper Mountain Conference on Iterative Methods, April 1996.

Henson, V.E., M. Limber, S. McCormick, B.T. Robinson, "Spotlight Computed Tomography with Natural Pixels," Fifth SIAM Conference on Linear Algebra, Snowbird, Utah, June 1994.

Henson, V.E., M. Limber, S. McCormick, B.T. Robinson, "Multilevel image reconstruction with natural pixels," Colorado Conference on Iterative Methods, Breckenridge, Colorado, April 1994.

Henson, V.E., and A. Shaker, "Multigrid and Multilevel Projection Methods for a Semilinear PDE in the Theory of Pseudoplastic Fluids," Copper Mountain Conference on Multigrid Methods, Copper Mountain, Colorado, April 1993.

Production Software Packages Developed

Developed BoomerAMG, a parallel algebraic multigrid (AMG) code, written in C, for the Center for Applied Scientific Computation, Lawrence Livermore National Laboratory (with U.M. Yang, LLNL).

Created FULFAN for Cities Service Oil & Gas Company, Western Region Office, Denver, CO., 1982-3. Adopted for use in all domestic Region Offices, 1984. FULFAN is a seismic forward-modeling package, which simulates reflection seismic data from hypothesized geologic structure. Includes both wave-theoretical and ray-theoretical approaches, seismic migration options, and seismic data processing options. Includes interactive user interface, seven driver routines, many computational kernels, and graphical output routines. Language: Fortran-77. Machines: Data General MV-8000, IBM Mainframe.

Created SEISMOD for Cities Service Oil & Gas Company, Western Region Office, Denver, CO., 1981-2. SEISMOD is a ray-theoretical seismic forward-modeling package. Later replaced by the more advanced FULFAN package. Language: Fortran-77. Machines: Data General MV-8000, IBM Mainframe.

Created SYNSEIS for Cities Service Oil & Gas Company, Western Region Office, Denver, CO., 1981. SYNSEIS is a package that generates synthetic seismograms from borehole acoustic logs. Includes interactive user interface, data-digitization, computational kernel, and graphical output routines. Language: Fortran-77. Machines: Data General MV-8000.

Created forward modeling routines for gravimetric exploration and magnetic exploration, for Cities Service Oil & Gas Company, Western Region Office, Denver, CO., 1984. These routines simulate gravity and magnetic signatures for given subsurface geologic structure. Later incorporated as a feature of the FULFAN package. Language: Fortran-77. Machines: Data General MV-8000.

Algorithms Developed/Research Codes

Developed parallel algebraic multigrid coarsening algorithms and implemented into parallel code BoomerAMG. Language: C. Lawrence Livermore national Laboratory, 1998-99.

Developed algorithms for natural-pixel based image reconstruction from projections (with M. A. Limber, B. T. Robinson, S. F. McCormick). Implemented as research code. Languages: C, Matlab. Naval Postgraduate School, 1993-1995.

Developed algorithms for Fourier-based image reconstruction from projections. Implemented as research code. Languages: Fortran77, IDL (Interactive Data Language). Implemented on DEC Unix workstation. University of Colorado, 1988-1990.

Developed algorithms for computing fast Fourier transforms (FFTs) for symmetric sequences on parallel computers. Algorithms developed for both shared-memory and distributed-memory architectures. Language: Parallel Fortran-77. Implemented in research codes on Sequent Balance and Intel Hypercube (University of Colorado) and Sequent Symmetry (Argonne National Laboratory). 1987-88.

Developed wave-theoretical algorithms for reflection seismic modeling. Incorporated into FULFAN modeling package. Cities Service Oil & Gas Company, Western Region Office, Denver, CO., 1982-3.

Parallel Processing

Currently developing BoomerAMG, a parallel AMG algorithm, for use in large-scale unstructured grid problems. Center for Applied Scientific Computation, Lawrence Livermore National Laboratory (with U. M. Yang, LLNL). Implementation to be in C using MPI for parallel communication.

Developed and implemented parallel FFT algorithms for shared-memory and distributed memory machines using explicit synchronized message passing. Experimented with asynchronous parallel FFT algorithms, for both symmetric and non-symmetric sequences. University of Colorado at Denver, 1987-88.

Dissertations Directed

Bruce T. Robinson, (PhD, Applied Mathematics) A multilevel approach to the algebraic image reconstruction problem, Naval Postgraduate School, June, 1994.

Theses Directed

Gerald N. Miranda, (MS, Applied Mathematics) Interpolation Weights for Algebraic Multigrid, Naval Postgraduate School, June 1997.

Thomas Rogers, (MS, Applied Mathematics) An FVE-FAC approach to the weldpool problem, Naval Postgraduate School, September, 1995.

Eric T. Litaker, (MS, Applied Mathematics) Finite Volume Element (FVE) discretization and multilevel solution of the axisymmetric heat equation, Naval Postgraduate School, December, 1994.

John Volk, (MS, Electrical Engineering) An analysis of multigrid techniques for system modeling with Toeplitz approximation, Naval Postgraduate School (jointly directed with Prof. Murali Tummala), September, 1994.

Christopher Rhoden, (MS, Applied Mathematics) Linear optimization and image reconstruction, Naval Postgraduate School, June, 1994.

Javier Nieto, (MS, Applied Mathematics; MS, Operations Analysis) Multigrid methods in network optimization: overview and appraisal, Naval Postgraduate School, (jointly directed with Prof. Gordon Bradley and Prof. Craig Rasmussen), March 1994.

Annette Cornett, (MS, Applied Mathematics) Multigrid approach to solving the long transportation problem on a regular grid in cost space, Naval Postgraduate School, (jointly directed with Prof. Craig Rasmussen), June, 1993.

Kevin J. Cavanaugh, (MS, Applied Mathematics; MS, Operations Analysis A multilevel approach to minimum cost network flows, Naval Postgraduate School, (jointly directed with Prof. Richard Rosenthal), September, 1992.

Hugh Joseph McBride, (MS, Applied Mathematics) Wave propagation in elastic solids, Naval Postgraduate School, (jointly directed with Prof. Clyde Scandrett), June, 1992.