Wen-Ching Yang is Advisory Engineer, Siemens Westinghouse Power Corporation, Pittsburgh, Pennsylvania. The author, coauthor, editor or coeditor of numerous journal articles, book chapters and books, he holds 11 patents and is a Fellow of the American Institute of Chemical Engineers and a member of the American Chemical Society. The recipient of the Fluor Daniel Lectureship Award in Fluidization (2000) and the Dow Chemical Fluidized Processes Recognition Award (1993), Dr. Yang received the B.S. degree (1962) in chemical engineering from the National Taiwan University, Taipei, Taiwan, the M.S. degree (1965) in chemical engineering from the University of California, Berkeley, and the Ph.D. degree (1968) from Carnegie Mellon University, Pittsburgh, Pennsylvania.