In this paper, a geometric process repair model for a k-dissimilar-component series repairable system with one repairman is proposed. For each component, the successive operating times form a decreasing geometric process whereas the consecutive repair times constitute an increasing geometric process. Under this assumption, we consider a replacement policyM = (N1,N2, . . . ,Nk) based respectivel...

Importance sampling is a potentially powerful technique for e ciently estimating the probabilities of rare events in discrete event systems. The work presented here makes three contributions to importance sampling research. First, a convenient mechanism for specifying complex importance sampling heuristics is presented. Second, a method for applying importance sampling to stochastic activity ne...

The increasing complexity of vehicle design, the use new engine types and fuels, intelligence automobiles are making it increasingly difficult to ensure trouble-free operation. Finding faulty parts quickly accurately is becoming difficult, as diagnostic process requires analyzing a great amount information. Therefore, we propose an approach based on association rules, machine learning technique...

In this thesis we study online optimization problems in routing and scheduling. An online problem is one where the problem instance is revealed incrementally. Decisions can (and sometimes must) be made before all information is available. We design and analyze (polynomial-time) online algorithms for a variety of problems. We utilize worst-case competitive ratio (and relaxations thereof), asympt...