Teow-Hin Ngair

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We demonstrate how order-theoretic abstractions can be useful in identifying , formalizing, and exploiting relationships between seemingly dissimilar AI algorithms that perform computations on partially-ordered sets. In particular, we show how the order-theoretic concept of an anti-chain can be used to provide an eecient representation for such sets when(More)
In this paper we present a method of attacking public-key cryptosystems (PKCs) on tamper resistant devices. The attack makes use of transient faults and seems applicable to many types of PKCs. In particular, we show how to attack the RSA, the ElGamal signature scheme, the Schnorr signature scheme, and the DSA. We also present some possible methods to(More)
This paper presents a new on-line cash check scheme which guarantees payor anonymity and improves upon existing similar schemes in efficiency and security. Electronic commerce, which combines the efficiency of computerization and networking, is going to dramatically change the way in which business is conducted today. One of the key issues for the(More)
The Assumption-based Truth Maintenance System (ATMS) is a general and powerful problem-solving tool in AI. Unfortunately, its generality usually entails a high computational cost. In this paper, we study how a general notion of cost function can be incorporated into the design of an algorithm for focusing the ATMS, called BF-ATMS. The BF-ATMS algorithm(More)
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