College of Mathematics and Information Sciences, Henan University, Kaifeng 475001, China; Basic Courses Depravement, Zhengzhou Economic Management Institute, Zhengzhou 450002, China
About author:WANG Zhi-guo(1954-),male,native of Xinzheng,Henan,an associate professor of Henan University,engages in graph theory and in nonlinear programming.
