Yang Xu is Mathematical Professor in the College of Mathematics, Southwest Jiaotong University, P.R.China. He is a Mid-Youth Expert of Outstanding Contribution of P.R.China. He received the Ph.D. degree in transportation management engineering from Southwest Jiaotong University, P.R. China, in 1996. His major research interests lie in the areas of mathematics, logic, system science, intelligent information processing. He has (co)authored over 600 papers and 9 books on his research topics.