organization


2017

  • (with K. Ren and J. Zou) Minisymposium on Inverse Problems in Scattering and Imaging, Applied Inverse Problems Conference, Zhejiang University, Hangzhou, May 29-June 2, 2017
  • (with H. Ammari, G. Bao, S. Moskow, and J. Schotland) IMA Annual Program Year Workshop: Optical Imaging and Inverse Problems, The Institute for Mathematics and its Applications, University of Minnesota, Minneapolis, MN, February 13-17, 2017.

2016

  • (with J. Shen and P. Stefanov) Workshop on Inverse Problems in Scattering and Imaging, Purdue University, West Lafayette, IN April 22-23, 2016.
  • (with H. Zhou) Minisymposium on Inverse Problems and Imaging, The 40th SIAM Southeastern Atlantic Section Conference, University of Georgia, Athens, GA, March 12-13, 2016.

2015

  • Special Session on Inverse Scattering Problems, International Conference on Inverse Problems, Imaging, and Applications, Zhejiang University, Hangzhou, China, August 6-9, 2015.
  • (with G. Bao and F. Triki) Minisymposium on Inverse Problems in Wave Propagation, The 8th International Congress on Industrial and Applied Mathematics, Beijing, China, August 10-14, 2015.
  • (with G. Bao and J. Zou) Minisymposium on Inverse Problems in Optics, Applied Inverse Problems Conference, University of Helsinki, Finland, May 25-29, 2015.

2014

  • (with Y. Lu) Special Session on Wave Propagation, International Conference on Applied Mathematics, City University of Hong Kong, Hong Kong, December 1-5, 2014.
  • (with G. Bao, J. Lin, and X. Xu) The Third International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 7-10, 2014.

2013

  • (with G. Bao) Workshop on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, December 19-21, 2013.
  • (with W. Zheng) Workshop on Numerical Methods for Wave Propagation, The Second International Conference on Engineering and Computational Mathematics, Hong Kong Polytechnic University, Hong Kong, December 16-18, 2013.
  • (with J. Sun and Y. Xu) Special Session on Applied Analysis and Inverse Problems, AMS Sectional Meeting, University of Louisville, Louisville, KY , October 5-6, 2013.
  • (with G. Bao) Minisymposium on Inverse Scattering Problems, Applied Inverse Problems Conference, Korea Advanced Institute for Sciences and Technology, Daejeon, Korea, July 1-5, 2013.
  • (with K. Ren) Minisymposium on Inverse Problems for Wave Propagation in Complex and Random Environments, Applied Inverse Problems Conference, Korea Advanced Institute for Sciences and Technology, Daejeon, Korea, July 1-5, 2013.
  • (with G. Bao, J. Cheng, D. Dobson), The Second International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 19-23, 2013.
  • (with J. Shen) Workshop on Inverse Problems in Scattering and Imaging, Department of Mathematics, Purdue University, West Lafayette, IN, April 12-13, 2013.
  • (with A. Wood) Special Session on Mathematical Aspects on CEM, the 29th International Review of Progress in Applied Computational Electromagnetics, Monterey, CA, March 24-28, 2013.
  • (with G. Bao and D. Liu) Minisymposium on Modeling, Analysis, and Computation for Wave Propagation in Optics and Electromagnetics, Hong Kong Baptist University, Hong Kong, China, January 1-7, 2013.

2012

  • Minisymposium on Acoustic and Electromagnetic Wave Propagation, International Conference on Mathematical Modeling, Analysis and Computation, Xiamen University, Xiamen, China, July 21-25, 2012.
  • (with J. Sun) Minisymposium on Direct and Inverse Scattering for Wave Propagation, Eighth International Conference on Scientific Computing and Applications. University of Nevada, Las Vegas, Nevada, April 1-4, 2012.

2011

  • (with D. Dobson) Special Session on Electromagnetic Wave Propagation in Complex and Random Environments, AMS Sectional Meeting, University of Utah, Salt Lake City, Utah, October 22-23, 2011.
  • Special Session on Electromagnetic Wave Propagation in Complex Media, International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 17-21, 2011.
  • (with J. Zou) Minisymposium on Identification of Distributed Parameters: Stability \& Numerics, Applied Inverse Problems Conference, Texas A\&M University, College Station, Texas, May 23-27, 2011.
  • (with J. Shen and J. Xia), Midwest Numerical Analysis Day 2011, Department of Mathematics, Purdue University, Indiana, May 7-8, 2011.



presentation


2018

  • Special Session on Recent Advances in Inverse Problems, The 12th bi-annual Conference on Dynamical Systems, Differential Equations and Applications, Taipei, Taiwan, July 2018.
  • Special Session on Waves and Computation, International Conference on Applied Mathematics, City University of Hong Kong, Hong Kong, China, June 2018.
  • Conference on Applied Mathematics, Florida International University, Miami, FL, January 2018.

2017


  • The International Conference on Recent Advances in Computational and Applied Mathematics, Wuhan University, Wuhan, China, December 2017.
  • Colloquium, Department of Applied Mathematics, Illinois Institute of Technology, Chicago, IL, September 2017.
  • Seminar, Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing, China, August 2017.
  • Seminar, Institute of Computational Mathematics, Chinese Academy of Sciences, Beijing, China, August 2017.
  • Seminar, School of Mathematics and Statistics, Northeast Normal University, Changchun, China, July 2017.
  • Inverse Problems and Image Analysis Seminar, The Fields Institute for Research in the Mathematical Sciences, Toronto, Canada, July 2017.
  • Inverse Problems and Image Analysis Colloquium, The Fields Institute for Research in the Mathematical Sciences, Toronto, Canada, July 2017.
  • International Workshop on Optimization in Scientific Computing, Chinese University of Hong Kong, Hong Kong, June 2017.
  • Minisymposium on Super-resolution in Imaging and Inverse Problems, Applied Inverse Problems Conference, Zhejiang University, Hangzhou, China, May 2017.
  • Minisymposium on Mathematical Methods for Inverse Medium Scattering, Applied Inverse Problems Conference, Zhejiang University, Hangzhou, China, May 2017.
  • Math/ICES Center of Numerical Analysis Seminar, University of Texas at Austin, Austin, TX, April 2017.
  • Minisymposium on Recent Developments on Inverse Scattering Problems, 100 Years of the Radon Transform, The Radon Institute of Computational and Applied Mathematics, Linz, Austria, March 2017. 
  • IMA Annual Program Year Workshop: Optical Imaging and Inverse Problems, The Institute for Mathematics and its Applications, University of Minnesota, Minneapolis, MN, February 2017.
  • Minisymposium on Numerical Simulation of Optical and Plasmonic Phenomena, SIAM Conference on Computational Science and Engineering, Atlanta, GA, February 2017. 
  • Annual Program Seminar Series, The Institute for Mathematics and its Applications, University of Minnesota, Minneapolis, MN, February 2017.

2016


  • Workshop on Mathematical Analysis of Metamaterials and Applications, Tsinghua Sanya International Mathematics Forum, Sanya, China, December 2016.
  • The LIASFMA (Sino-French International Associated Laboratory for Applied Mathematics) Workshop on Control and Inverse Problems of Partial Differential Equations, Zhejiang University, Hangzhou, China, October, 2016. 
  • Analysis and Applied Mathematics  Seminar, Department of Mathematics, Statistics, and Computer Science, University of Illinois at Chicago, Chicago, IL, September 2016.
  • The International Conference on Numerical Analysis and Inverse Problems, Michigan Technological University, Houghton, MI, August 2016.
  • Minisymposium on Direct and Inverse  Scattering in Electromagnetics and Optics, SIAM  Annual Meeting, Boston,  MA, July 2016.
  • The Fourth International Workshop on Computational Inverse Problems and Applications, Shangdong University of Technology, Zibo, China, July 2016. 
  • Minisymposium on Qualitative and Quantitative Inverse Scattering Algorithms, International Conference on Inverse Problems and Related Topics, Ewha Womans University, Seoul, Korea, June 2016.
  • Eighth International Workshop on Theoretical and Computational Analyses for Inverse Problems, Academy of Mathematics and Systems Science, Beijing, China, June 2016.
  • Minisymposium on Numerical Methods for Optics and Photonics, The Mathematics of Finite Elements and Applications, Brunel University, London, UK, June 2016.

2015

  • Workshop on Inverse Problems and Related Topics, Zhejiang University, Hangzhou, China, December 2015.
  • Minisymposium on Mathematics of Optics and Photonics, SIAM Conference on Analysis of Partial Differential Equations, Scottsdale, AZ, December 2015.
  • International Conference on Numerical Mathematics and Scientific Computing, Nanjing University, Nanjing, China,  August 2015. 
  • Seminar, Department of Mathematics, Southeast University, Nanjing, China, August 2015.
  • The 2nd Chongqing Workshop on  Computational and Applied Mathematics, Chongqing University, Chongqing, China, August 2015.
  • Minisymposium on Mathematics and Optics, The 8th International Congress on Industrial and Applied Mathematics, Beijing, China, August 2015.
  • Minisymposium on Optimization Methods for Inverse Problems, The 8th International Congress on Industrial and Applied Mathematics, Beijing, China, August 2015.
  • Minisymposium on Computational Electromagnetism and Its Engineering Applications, The 8th International Congress on Industrial and Applied Mathematics, Beijing, China, August 2015.
  • International Conference on Inverse Problems, Imaging, and Applications, Zhejiang University, Hangzhou, China, August 2015.
  • Seminar, School of Mathematics, Jilin University, Changchun, China, August, 2015.
  • Mini-course, School of Mathematics and Statistics, Northeast Normal University, Changchun, China, July 2015.
  • Workshop on Scientific Computation with Applications, Michigan State University, East Lansing, MI, July 2015.
  • Applied Inverse Problems Conference, University of Helsinki, Finland, May 2015.
  • Inverse Problems Seminar, Department of Mathematics, Colorado State University, Fort Collins, CO, March 2015.
  • Minisymposium on Inverse Problems and Imaging, The 39th SIAM Southeastern Atlantic Section Conference, University of Alabama, Birmingham, AL, March 2015.

2014

  • Workshop on Scattering and Inverse Scattering Problems, Zhejiang University, Hangzhou, China, December 2014.
  • Minisymposium on Analysis and Computation for PDE-based Inverse Problems, The Fifth International Conference on Scientific Computing and Partial Differential Equations, Hong Kong Baptist University, Hong Kong, December 2014.
  • International Conference on Inverse Problems and Optimal Control, Chinese University of Hong Kong, Hong Kong, December 2014.
  • Special Session on Wave Propagation, International Conference on Applied Mathematics, City University of Hong Kong, Hong Kong, December 2014.
  • Seminar, Department of Mathematics, University of Macau, Macau, China, November 2014.
  • Colloquium, Department of Mathematics, Chinese University of Hong Kong, Hong Kong, November 2014.
  • Mathematical Analysis and its Applications Colloquium, the Liu Bie Ju Center for Mathematical Sciences, City University of Hong Kong, Hong Kong, October 2014. 
  • Colloquium, Department of Mathematics, Hong Kong Baptist University, Hong Kong, October 2014.
  • Seminar, Institute of Applied Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing, August 2014.
  • Seminar, College of Mathematics and Statistics, Chongqing University, Chongqing, China, July 2014.
  • Mini-course, School of Mathematics and Statistics, Northeast Normal University, Changchun, China, July 2014. 
  • Workshop on Numerical Methods for Partial Differential Equations, School of Mathematics, Jilin University, Changchun, July 2014.
  • Seminar of Team EDP-MOISE, Laboratoire Jean Kuntzmann, University of Joseph Fourier, Grenoble, France, June 2014.
  • The Third International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 2014.
  • Seminar, Department of Mathematics, Zhejiang University, Hangzhou, China, May 2014.
  • Computational Mathematics Seminar, Department of Mathematics, University of Macau, Macau, China, May 2014.
  • Seminar, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, May 2014. 
  • Minisymposium on Inverse Scattering Problems in Imaging Science, SIAM Conference on Imaging Science, Hong Kong Baptist University, Hong Kong, China, May 2014.
  • Mathematical Sciences Colloquium, Department of Mathematical Sciences, Rensselaer Polytechnic Institute, Troy, NY, March 2014.
  • Applied Mathematics Seminar, Department of Mathematics and Statistics, Auburn University, Auburn, AL, January 2014.

2013

  • Workshop on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, December 2013.
  • Workshop on Numerical Methods for Wave Propagation, The Second International Conference on Engineering and Computational Mathematics, Hong Kong Polytechnic University, Hong Kong, December 2013.
  • Special Session on Applied Analysis and Inverse Problems, AMS Sectional Meeting, University of Louisville, Louisville, KY , October 2013.
  • Colloquium, Department of Mathematical Sciences, Indiana University-Purdue University Indianapolis, Indianapolis, IN, August 2013.
  • The Copper Country Summer Workshop on Numerical Analysis and Inverse Problems, Michigan Technological University, Houghton, MI, August 2013.
  • The Third International Workshop on Computational Inverse Problems and Applications, Nanchang, China, July 2013.
  • Colloquium, School of Mathematics and Statistics, Central China Normal University, Wuhan, China, July 2013.
  • Minisymposium on Inverse Scattering Problems, The Applied Inverse Problem Conference, Korea Advanced Institute for Sciences and Technology, Daejeon, Korea, July 2013.
  • Inverse Problems Seminar, Department of Mathematics, School of Information, Renmin University of China, Beijing, China, June 2013.
  • Computational Mathematics Seminar, Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, China, June 2013.
  • The Second International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 2013.
  • The Tenth Annual Conference on Frontiers in Applied and Computational Mathematics, New Jersey Institute of Technology, Newark, NJ, May 2013.
  • Special Session on Numerical Methods for Geometric Partial Differential Equations, AMS Sectional Meeting, Iowa State University, Ames, IA, April 2013.
  • Special Session on Numerical Analysis and Scientific Computing, AMS Sectional Meeting, Iowa State University, Ames, IA, April 2013.
  • Partial Differential Equations Seminar, Department of Mathematics, University of Houston, Houston, TX, March 2013.
  • Special Session on Mathematical Aspects on CEM, the 29th International Review of Progress in Applied Computational Electromagnetics, Monterey, CA, March 2013.
  • Seminar on Inverse Problems and Analysis, Department of Mathematics, University of Delaware, Newark, DE, March 2013.
  • Minisymposium on Numerical Methods for Electromagnetic Problems, The 8th International Conference on Computational Physics, Hong Kong Baptist University, Hong Kong, China, January 2013.
  • Minisyposium on Modeling, Analysis, and Computation for Wave Propagation in Optics and Electromagnetics, The 8th International Conference on Computational Physics, Hong Kong Baptist University, Hong Kong, China, January 2013.

2012

  • International Workshop on Recent Advances in Scientific and Engineering Computing, Department of Mathematics, Shanghai Jiao Tong University, Shanghai, China, October 2012.
  • International Conference on Inverse Problems and Applications, Zhejiang University, Hangzhou, China, September 2012.
  • Bridge to Research Seminar, Department of Mathematics, Purdue University, West Lafayette, IN, September 2012.
  • Workshop on Scattering and Inverse Scattering Problems and Applications, Michigan State University, East Lansing, MI, August 2012.
  • International Conference on Mathematical Modeling, Analysis and Computation, Xiamen University, Xiamen, China, July 2012.
  • Seminar, Department of Mathematical Sciences, Tsinghua University, Beijing, China, July 2012.
  • Computational Mathematics Seminar, Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, China, July 2012.
  • Minisymposium on Propagation, Scattering and Inverse Scattering of Optical Waves, SIAM Annual Meeting, Minneapolis, MN, July 2012.
  • Inverse Problems and Imaging Seminar, University of California at Irvine, Irvine, CA, June 2012.
  • International Conference on Applied Mathematics 2012, City University of Hong Kong, Hong Kong, China, May 2012.
  • Special Session on Mathematical Aspects of CEM, The 28th International Review of Progress in Applied Computational Electromagnetics, Columbus, OH, April 2012.
  • Colloquium, Department of Mathematics and Statistics, Air Force Institute of Technology, WPAFB, OH, April 2012.
  • Minisymposium on Advances in Analytical and Computational Techniques for Nonlinear Waves, 8th International Conference on Scientific Computing and Applications, University of Nevada at Las Vegas, NV, April 2012.
  • 8th International Conference on Scientific Computing and Applications, University of Nevada at Las Vegas, NV, April 2012.
  • Special Session on Inverse Problems in PDEs, AMS Sectional Meeting, University of South Florida, Tampa, FL, March 2012.

2011

  • The Fourth International Conference on Scientific Computing and Partial Differential Equations, Hong Kong Baptist University, Hong Kong, China, December 2011.
  • Applied Mathematics Lunch Seminar, Purdue University, West Lafayette, IN, November 2011.
  • Special Session on Inverse Problems and Homogenization, AMS Sectional Meeting, University of Utah, Salt Lake City, UT, October 2011.
  • GMIG Pure and Applied Math Seminar, Purdue University, West Lafayette, IN, October 2011.
  • Minisymposium on Numerical Methods for Electromagnetic and Acoustic Wave Problems, the 7th International Congress on Industrial and Applied Mathematics, Vancouver, BC, Canada, July 2011.
  • Applied Mathematics Seminar, Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing, China, June 2011.
  • Computational Mathematics Seminar, Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, China, June 2011.
  • International Conference on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 2011.
  • 2011 Applied Mathematics and Image Processing Summer Workshop, University of Texas at Pan American, Edinburg, TX, May 2011.
  • 2011 DTRA/NSF Algorithm Workshop, Boston, MA, June 2011.
  • Minisymposium on  Recent Developments of Reconstruction Methods for Inverse Scattering Problems, Applied Inverse Problems Conference, Texas A&M University, College Station, TX, May 2011.
  • Minisymposium on Identification of Distributed Parameters: Stability &  Numerics,
    Applied Inverse Problems Conference, Texas A&M University, College Station, TX, May 2011.
  • Applied Mathematics Seminar, Wayne State University, Detroit, MI, April 2011.
  • MCIAM Workshop on Computational Wave Propagation, Michigan State University, East Lansing, MI, April 2011.
  • Special Session on Numerical Analysis and Scientific Computing, AMS Sectional Meeting, University of Iowa, Iowa City, IA, March 2011.
  • pre-AMS VIGRE Workshop, University of Iowa, Iowa City, IA, March 2011.

2010

  • Applied and Computational Mathematics Seminar, University of California at Irvine, Irvine, CA, November 2010.
  • The 10th International Workshop on Finite Elements for Microwave Engineering, Meredith, NH, October 2010.
  • International Symposium on Maxwell's Equations: Theoretical and Numerical Issues with Applications, Fudan University, Shanghai, China, July 2010.
  • Computational Mathematics Seminar, Institute of Computational Mathematics and Scientific/Engineering Computing, Chinese Academy of Sciences, Beijing, China, July 2010.
  • The Second International Workshop on Computational Inverse Problems and Applications, Beijing, China, July 2010.
  • IMA Graduate Student Summer Program: Computational Wave Propagation, Michigan State University, East Lansing, MI, June 2010.
  • International Conference on Applied Mathematics, City University of Hong Kong, Hong Kong, China, June 2010.
  • Workshop on Interdisciplinary Applied and Computational Mathematics, Zhejiang University, Hangzhou, China, June 2010.
  • Minisymposium on Numerical Inversion, Optimization and Large Scale Scientific Computing, the 5th International Conference "Inverse Problems: Modeling and Simulation", Antalya, Turkey, May 2010.
  • Midwest Numerical Analysis Day, Iowa State University, Ames, IA, April 2010.
  • Workshop on Inverse Problems: Theory, Computation, and Applications, Michigan Center for Industrial and Applied Mathematics, Michigan State University, East Lansing, MI, April 2010.
  • Special Session on Differential Equations and Applications, AMS Sectional Meeting, St. Paul, MN, April 2010.
  • Bridge to Research Seminar, Department of Mathematics, Purdue University, West Lafayette, IN, March 2010.
  • Colloquium, Department of Mathematics, University of Louisville, Louisville, KY, Februray 2010.

2009

  • The Finite Element Circus, University of Tennessee, Knoxville, TN, October 2009.
  • Minisymposium on Mathematical and Computational Challenges on Inverse and Control Problems for Differential Equations, International Conference on Scientific Computation and Differential Equations, Beijing, China, May 2009.
  • Minisymposium on Applications to Computational Electromagnetics, International Conference on Scientific Computation and Differential Equations, Beijing, China, May 2009.
  • Joint Midwest Numerical Analysis Day & SIAM Great Lakes Numerical PDEs Spring Conference, Wayne State University, Detroit, MI, April 2009.
  • Applied Mathematics Seminar, Florida International University, Miami, FL, Februray 2009.

2008

  • Applied Mathematics Lunch Seminar, Purdue University, West Lafayette, IN, October 2008.
  • International Conference on Inverse Problems and its Applications, Fudan University, Shanghai, China, October 2008.
  • Applied and Computational Mathematics Seminar, Georgia Institute of Technology, Atlanta, GA, September 2008.
  • Applied Mathematics Seminar, Wayne State University, Detroit, MI, April 2008.
  • Special Session on Finite Element Methods and Application, AMS Sectional Meeting, Bloomington, IN, April 2008.
  • (poster) Multiscale modeling, analysis, and simulation, Michigan State University, East Lansing, MI, March 2008.
  • Colloquium, Department of Mathematics and statistics, University of Missouri, Kansas City, MO, February 2008.
  • Colloquium, Department of Mathematics, University of South Carolina, Columbia, SC, February 2008.
  • Colloquium, Department of Mathematics and & Statistics, Wichita State University, Wichita, KS, January 2008.
  • Colloquium, Department of Mathematics, Purdue University, West Lafayette, IN, January 2008.

2007

  • Minisymposium on Recent Developments in Computation and Analysis of Wave Propagation and Application in Optics, SIAM Conference on Analysis of PDEs, Mesa, AZ, December 2007.
  • Special Session on Wave Propagation from Mathematical and Numerical Viewpoints, AMS Sectional Meeting, Chicago, IL, September 2007.
  • Applied Mathematics Seminar, Fudan University, Shanghai, China, August 2007.
  • International Conference on Computational Mathematics and Geophysics, Beijing, China, July 2007.
  • Applied Mathematics Seminar, Huazhong Agricultural University, Wuhan, China, June 2007.
  • SIAM Conference on Computational Science and Engineering, Costa Mesa, CA, February 2007.

2006

  • (poster) IMA ``Hot Topics" Workshop: Negative Index Materials, Twin Cities, MN, October 2006.
  • (poster) Midwest Quantitative Biology Conference, Mackinac Island, MI, September 2006.
  • Recent Mathematical and Computational Developments of Maxwell's Equations: Challenges and Frontiers, Weihai, China, July 2006.
  • SIAM Annual Meeting, Boston, MA, July 2006.
  • Applied Mathematics Seminar, Michigan State University, East Lansing, MI, May 2006.

2005

  • 7th International Conference on Mathematical and Numerical Aspects of Wave Propagation, Boston, MA, June 2005.
  • Applied and Interdisciplinary Mathematics Seminar, University of Michigan, Ann Arbor, MI, March 2005.
  • Third Annual MSU Student Mathematics Conference, Michigan State University, East Lansing, MI, March 2005.
  • Colloquium, Applied and Computational Mathematics, California Institute of Technology, Pasadena, CA, February 2005.

2004

  • PDEs Seminar, Michigan State University, MI, September 2004.
  • Second Annual MSU Student Mathematics Conference, Michigan State University, East Lansing, MI, March 2004.

2003

  • First Annual MSU Student Mathematics Conference, Michigan State University, East Lansing, MI, March 2003.