1. Environmental Services, SpecPro Inc., San Antonio, Texas, United States
2. Department of Mathematics and Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
3. School of Computing, University of Southern Mississippi, Hattiesburg, Mississippi, United States
4. Department of Mathematics, University of Southern Mississippi, Hattiesburg, Mississippi, United States
5. Environmental Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, Mississippi, United States