1. Visiting assistant professor, research specialist, and professor, respectively, Department of Agricultural Engineering, University of Illinois, Urbana, IL 61801. Mention of brand or firm names does not constitute an endorsement by the U.S. Department of Agriculture or the University of Illinois above others of a similar nature not mentioned.
2. Corresponding author. Phone: 215-233-6714; Fax: 215-233-6559; E-mail: vsingh@arserrc.gov
3. Lead scientist and research leader, respectively, United States Department of Agriculture, Eastern Regional Research Center, Agricultural Research Service, Wyndmoor, PA 19038.