1. Assistant Research Scientist, Hydrological Sciences Branch, NASA Goddard Space Flight Center, Greenbelt, MD 20771.
2. Federal Postdoctoral Civil Engineer, U.S. EPA-NRMRL, Sustainable Technology Div., Systems Analysis Branch, Cincinnati, OH 45268.
3. Professor, Civil, Construction, and Environmental Engineering, North Carolina State Univ., Raleigh, NC 27695.
4. Associate Professor, Civil, Construction, and Environmental Engineering, North Carolina State Univ., Raleigh, NC 27695.