Sharif Digital Repository

EOQ and EPQ models have been among the most important and commonly used techniques for about 100 and 60 years respectively .But, they are involved in some assumptions that sometimes prevent them from being implemented in real situation of industry and production. One of these unrealistic assumptions is that all of items received or produced are of perfect quality. In order to overcome this constraint and make the mentioned models closer to the real environmentsome researches have been done. To this end,following the previous attemptsin this project we assumed to have destructive inspections and existence of imperfect and rejected items after rework. In our models, considering 3 circumstances... 

In real production systems, the process is always bound with the production of faulty items which different approaches may be taken toward handling these low quality items according to the nature of the industry and product. Repairing, discarding or selling items in a secondary market are some of the possible actions. We investigated the essentiality of coordinated decision making between a supplier and a buyer in this environment hence developing a model to minimize total costs of two parties with an attitude towards improving quality of production system. In common two layered supply chains, the buyer defines the economic order quantity (EOQ) according to its own decision criteria. These... 

In this research we will develop an algorithm to find the optimal robust solution via simulation optimization by using an artificial neural network metamodel. Following Taghuchi, in design phase of the algorithm, we will discriminate between decision or control variables and environmental or noise variables. To arrive of the best new solution in every iteration, the algorithm will use a symmetrical probabilistic distribution about the optimum point of the previous iteration. In comparison with the existing methods, our algorithm displays an improvement in results when applied to such problems as single channel queueing system problem and economic order quantity problem