1. Illinois Institute of Technology,Dept. of Elec. and Comp. Engr.,Chicago,IL,U.S.A.
2. Illinois Institute of Technology,Chicago,IL,U.S.A.
3. East Tennessee State University,Dept. of Biomedical Sciences,Johnson City,TN,U.S.A.
4. Loyola Univ. Med. Ctr. and Hines VA Hosp.,Department of Medicine,Maywood,IL,U.S.A.