Showing papers by "Matteo Sonza Reorda published in 1993"

Hybrid Genetic Algorithms for the Travelling Salesman Problem

Abstract: A comparative analysis is performed on an experimental basis among four different cross-over operators. In order to exploit the benefits of the different operators, a new one (called Mixed Cross-over) is introduced, trading-off the CPU time requirements and the obtained results. A new operator is then proposed, whose goal is to include in the genetic mechanism some heuristic knowledge drawn from the already proposed local-optimization techniques. The performance of the new operator is discussed.

An Approach to Sequential Circuit Diagnosis Based on Formal Verification Techniques

Abstract: This article deals with the generation of exact diagnostic trees for real-size synchronous sequential circuits. Starting from existing detection-oriented test patterns, a modified fault simulator is used for assessing their diagnostic power, which, in general, is not satisfactory. A diagnostic procedure for improving it is described that successfully exploits symbolic FSM equivalence proof algorithms. In order to resort to costly techniques, such as product machine traversal, only when really needed, special checks are performed to verify combinational identity and identity on reachable states. As all faults are attributed to theirequivalence class, a complete and exact diagnostic tree can be built. Experimental results on ISCAS'89 circuits show the feasibility of the approach and support the claim that, for the first time, diagnosing real-world synchronous sequential circuits has become feasible.