Production planning and maintenance are two important problems in manufacturing systems. Despite the relationship exists between these two problems due to sudden failures and production capacity occupied by maintenance activities, each of these problems planned separately and as a result program and model efficiencies reduce in the real world. The aim of integrated production and maintena...

This paper has been worked on a RAP with multi-state components and the performance rate of each component working state may increase by spending technical and organizational activities costs. Whereas RAP belongs to Np-Hard problems, we used Genetic algorithm (GA) and simulated annealing (SA) and for solving the presented problem and calculating system reliability universal generating function ...

A CSS1†is a system with the continues-state components. When a component has the ability to obtain all the situations from completely working to completely failed, it named continues-state component. In the real world, performance rate of elements are continuous and decrease by time. Continuity of components causes infinite working states and grows up the system states. In this paper we propose...

This paper presents a mathematical model for an inventory control system in which customers’ demands and suppliers’ service time are considered as stochastic parameters. The proposed problem is solved through queuing theory for a single item. In this case, transitional probabilities are calculated in steady state. Afterward, the model is extended to the case of multi-item inventory systems. The...

The objective of the continuous time mean-variance model is to minimize variance (risk) an investment portfolio with a given mean at terminal time. However, investor can stop plan any before To solve this problem, we consider variances in multi-time state. advantage state minimization risk within period. obtain optimal strategy model, introduce sequence Riccati equations, which are connected by...