Linear logic for deductive databases

This paper deals with deductive databases in linear logic. The semantics of queries, views, constraints, and (view) updates are defineddeclaratively in linear logic. In constrast to classical logic, we can formalise non-shared view, transition constraints, and (view) updates easily. Various proof search strategies are presented along with an algorithm for query evaluation from a bottom-up direction. An additional advantage is that the associated meaning of a given relation can be defined in terms of the validity of a legal update in a given relation. We also defined formally the update principles and showed the correctness of the update translation algorithms. In this approach, we provide virtual view updates along with real view updates, and view DELETIONs are special cases of view REPLACEMENTs. This permits three transactional view update operations (INSERTION, DELETION, REPLACEMENT) in comparison to only (INSERTION, DELETION) in most existing systems. Dong-Tsan Lee, Ph.D.: He is a computer scientist in the Department of Computer Science at University of Western Australia, Perth, Western Australia, Australia. He received the B.S. and M.S. degrees from the Department of Computer Science at National Chiao-Tung University, Taiwan, in 1983 and 1985, respectively, and earned the Ph.D. degree from the Department of Computer Science at University of Western Australia. His research interests include database and artificial intelligence, linear logic, and real-time software engineering. Chin-Ping Tsang, Ph.D.: He is currently an associate professor in the Department of Computer Science at University of Western Australia, Perth, Western Australia, Australia. He received the Ph.D. degree from the University of Western Australia. He was the head of the Department of Computer Science at the University of Western Australia from 1994 to 1997. His research interests include artificial intelligence, non-classicial logic and neural nets.     

Re-examining the security issues of ATM systems

The automated teller machine (ATM) system is the well-known system in E-society that provides us with easy access to banking activities, e.g. money transfers between a user's accounts. This article focuses on the security issues of ATM systems. We examine a criminal case concerning large-scale fraudulent cash withdrawals at ATMs around Taiwan. The common tricks used by criminals are copies of cards as well as the use of tiny cameras to record the personal identification numbers of card users. With continued advances in technology, the criminal case can be handled easily. We also discuss security policies to prevent fraudulent cash withdrawals.     

Evaluating real-time software specification languages

In recent years, many notations and methods in real-time software engineering have been proposed. However, thorough experimentation to evaluate these notations and methods has not been carried out. This paper focuses on real-time software engineering specification languages: Unified Modeling Language (UML), Real-Time Object-Oriented Modeling Language (ROOM), Modecharts, statecharts, Mealy and Moore machines, finite state machines, classical logic, Z, ASTRAL, temporal logic, FNLOG, linear logic, Timed Communicating Sequential Processes (TCSP), Temporal Calculus of Communicating Systems (TCCS), ρ1, and Multilevel Specification. The basis for evaluating these software engineering specification languages is by using the Turing machines and Interaction machines. We classify them based on their computational capabilities.