1Dept. of EE & CS University of Kansas Lawrence, KS 66045, USA
2Dept. of Comp. Sci. San Jose State Univ. San Jose, CA 95192, USA
3Dept. of Comp. Sci.San Jose State Univ.San Jose, CA 95192, USA
4Dept. of Math. Sci.SUNY at Fredonia Fredonia, NY 14063, USA