Y. Bai and Y. Zhang, On the computational aspect of logical database updates. Proceedings of IEA/AIE-2001. Lecture Notes in Artificial Intelligence, Vol 2070, 71-81. Springer, 2001.
Y. Zhang, C-M. Wu and Y. Bai, Implementing prioritized logic programming. Journal of Artificial Intelligence Communications (AICOM), Vol. 14, No. 4, 2001.
Y. Bai and V. Varadharajan, Access Control: Its Representation and Evaluation. Proceedings of IFIP/SEC2000 International Information Security Conference. pp232--235, 2000.
Y. Bai and V. Varadharajan, On Formal Languages for Sequences of Authorization Transformations. Proceedings of Safety, Reliability and Security of Computer Systems. Also in Springer-Verlag's Lecture Note in Computer Science 1999. pp375--384, Vol.1698, 1999.
Y. Bai and V. Varadharajan, Authorization in Object Oriented Databases. Proceedings of the Australasian Conference on Information Security and Privacy. Also in Springer-Verlag's Lecture Note in Computer Science 1999. pp270--280, Vol. 1587, 1999.
Y. Bai and V. Varadharajan, A Logical Formalization for Specifying Authorizations in Object Oriented Databases. Proceedings of IFIP Working Conference on Database Security, pp259--269, 1999.
Y. Bai and V. Varadharajan, A High Level Language for Conventional Access Control Models. Proceedings of the Australasian Conference on Information Security and Privacy. Also in Springer-Verlag's Lecture Note in Computer Science 1998. pp273--283, Vol. 1438, 1998.
Y. Bai and V. Varadharajan, A Model Based Semantics for Transformations of Authorization Policies. Proceedings of the 20th Australasian Computer Science Conference, pp383--391. 1997.
Y. Bai and V. Varadharajan, A Language for Specifying Sequences of Authorization Transformations and Its Applications. Proceedings of the International Conference on Information and Communication Security. Also in {\em Springer-Verlag's Lecture Note in Computer Science 1997, pp39--49, Vol. 1334, 1997.
Y. Bai and V. Varadharajan, Updating Policy Base: an Application of Knowledge Base in Authorizations. Proceedings of the IEEE First International Conference on Intelligent Processing Systems. pp1057--1067, Vol. 2, 1997.
Y. Bai and V. Varadharajan, A Formal Security Design Approach for Transformation of Authorizations in Information Systems. Proceedings of the 3rd Pacific Asia Conference on Information Systems, pp851--860, 1997.
Y. Bai and V. Varadharajan, A Logic for State Transformations in Authorization Policies. Proceedings of the 10th IEEE Computer Security Foundations Workshop, pp173--182, 1997.
Y. Bai and V. Varadharajan, Analysis and Implementation of a Formal Authorization Policy Design Approach. Proceedings of the Australasian Conference on Information Security and Privacy. Also in Springer-Verlag's Lecture Note in Computer Science 1997, pp14--25, Vol. 1270, 1997.