INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY On Two Stage Open Shop Scheduling in Which Processing Time, Set Up Time Associated with Probabilities Including Job Block Criteria Deepak Gupta, Manjeet Kaur *1,2 Department of Mathematics, Maharishi Markandeshwar University, Mullana, Ambala, India [email protected] Abstract The present paper is an attempt through heu...

The two machine routing open shop being a generalization of the metric TSP and two machine open shop scheduling problem is considered. It is known to be NP-hard even for the simplest case when the transportation network consists of two nodes only. For that simplest case it is known that the optimal makespan for any instance belongs to interval [R̄, 6 5 R̄], there R̄ is the standard lower bound. We...

In this paper, we consider the problem of scheduling n jobs on m machines in an open shop environment so that the sum of completion times or mean flow time becomes minimal. For this strongly NP-hard problem, we develop and discuss different constructive heuristic algorithms. Extensive computational results are presented for problems with up to 50 jobs and 50 machines, respectively. The quality ...

De Werra, D. and J. Blazewicz, Some preemptive open shop scheduling problems with a renewable or a nonrenewable resource, Discrete Applied Mathematics 35 (1992) 205-219. An edge coloring model is presented for a preemptive open shop problem. Constraints generated by a single resource have to be taken into account. The case of a renewable and of a nonrenewable resource as considered. Since the e...

We can reformulate a vehicle routing problem (VRP) as an open shop scheduling problem (SSP) by representing visits as activities, vehicles as resources on the factory floor, and travel as set up costs between activities. In this paper we present two reformulations: from VRP to open shop, and the inverse, from SSP to VRP. Not surprisingly, VRP technology performs poorly on reformulated SSP’s, as...

In this paper we consider a repair shop location problem with uncertainties in demand. New local repair shops have to be opened at a number of locations. At these local repair shops, customers arrive with broken, but repairable, items. Customers go to the nearest open repair shop. Since they want to leave as soon as possible, a (small) inventory of working items is kept at the repair shops. A c...

In this paper we study both the nonpreemptive and preemptive versions of the popular unit-time open shop scheduling problem. For the set of feasible schedules, we construct the linear description of the convex hull of the vectors of the job completion times. Based on the properties of the resulting scheduling polyhedron, we show that the problem of constructing an optimal schedule minimizing an...