The workflow satisfiability problem (WSP) is a planning problem. Certain sub-classes of this problem have been shown to be fixed-parameter tractable. In this paper we develop an implementation of an algorithm for WSP that has been shown, in our previous paper, to be fixed-parameter for user-independent constraints. In a set of computational experiments, we compare our algorithm to an encoding o...

In the facility location problem usually reducing total transferring cost and time are common objectives. Designing of a network with hub facilities can improve network efficiency. In this study a new model is presented for P-hub covering location problem. In the p-hub covering problem it is attempted to locate hubs and allocate customers to established hubs while allocated nodes to hubs are in...

In this paper, teaching–learning-based optimization (TLBO) is proposed to solve flexible job shop scheduling problem (FJSP) based on the integrated approach with an objective to minimize makespan. An FJSP is an extension of basic job-shop scheduling problem. There are two sub problems in FJSP. They are routing problem and sequencing problem. If both the sub problems are solved simultaneously, t...

This paper presents a new mathematical model for a production system through a scheduling problem considering a material handling system as an intelligent transportation system by automated guided vehicles (AGVs). The traditional systems cannot respond to the changes and customer’s demands and for this reason, a flexible production system is used. Therefore, for this purpose, automated transpor...

The problem of determining the sequence of a set of jobs with the objective function of minimizing the maximum earliness and tardiness in one machine is studied. &#10 Production systems like JIT are one of the many applications of the problem. This problem is studied in special cases and their optimal solutions are introduced with simple orders. In general, some effective conditions for ne...

the problem of several finite moving cracks in a functionally graded material is solved by dislocation technique under the condition of anti-plane deformation. by using the fourier transform the stress fields are obtained for a functionallygraded strip containing a screw dislocation. the stress components reveal the familiar cauchy singularity at thelocation of dislocation. the solution is empl...

In this paper we study the problem of solving hard propositional satisfiability problem (SAT) instances in a computing grid or cloud, where run times and communication between parallel running computations are limited. We study analytically an approach where the instance is partitioned iteratively into a tree of subproblems and each node in the tree is solved in parallel. We present new methods...