Malgorzata Sterna

Metaheuristic approaches for the two-machine flow-shop problem with weighted late work criterion and common due date

In this paper, metaheuristic approaches for the two-machine flow-shop problem with a common due date and the weighted late work performance measure (F2|dj=d|Yw) are presented. The late work criterion estimates the quality of a solution with regard to the duration of the late parts of jobs, not taking into account the quantity of the delay for the fully late activities. Since the problem mentioned is known to be NP-hard, three trajectory methods, namely simulated annealing, tabu search and variable neighborhood search are proposed based on the special features of the case under consideration. Then, the results of computational experiments are reported, in which the metaheuristics were compared one to each other, as well to an exact approach and a list scheduling algorithm.

Open shop scheduling problems with late work criteria

The paper concerns the application of a non-classical performance measure, a late work criterion (Y, Yw), to scheduling problems. It estimates the quality of the obtained solution with regard to the duration of the late parts of tasks not taking into account the quantity of this delay. The paper provides the formal definition of the late work parameter, especially in the shop environment, together with its practical motivation. It contains general complexity studies and the results of investigating open-shop scheduling cases, i.e. two polynomial time algorithms for problems O | pmtn, ri | Yw and O2 | di = d | Y, as well as the binary NP-hardness proof for O2 | di = d | Yw.

The disjunctive graph machine representation of the job shop scheduling problem

Abstract The disjunctive graph is one of the most popular models used for describing instances of the job shop scheduling problem, which has been very intensively explored. In this paper, a new time and memory efficient representation of the disjunctive graph is proposed. It has the form of a graph matrix and combines advantages of a few classical graph representations, enabling easy operating on the problem data. Computational experiments have proved higher efficiency of the proposed approach over the classical ones.

The two-machine flow-shop problem with weighted late work criterion and common due date

Abstract The paper is on the two-machine non-preemptive flow-shop scheduling problem with a total weighted late work criterion and a common due date ( F 2| d i = d | Y w ). The late work performance measure estimates the quality of the obtained solution with regard to the duration of late parts of tasks not taking into account the quantity of this delay. We prove the binary NP-hardness of the problem mentioned by showing a transformation from the partition problem to its decision counterpart. Then, a dynamic programming approach of pseudo-polynomial time complexity is formulated.

A comparison of solution procedures for two-machine flow shop scheduling with late work criterion

In this paper we analyze different solution procedures for the two-machine flow shop scheduling problem with a common due date and weighted late work criterion, i.e. for problem F2|dj = d|Yw, which is known to be binary NP-hard. In computational experiments we compare the practical efficiency of a dynamic programming approach, an enumerative method and a heuristic list scheduling procedure. Test results show that each solution method has its advantages and none of them can be rejected from consideration a priori.

Late work minimization in a small flexible manufacturing system

The paper concerns a small flexible manufacturing system consisting of three CNC machines: a lathe machine, milling machine and measurement center and a single robot, located at the Poznan University of Technology. A short description of the production environment, which can be modeled as the extended job shop system with open shop sections within particular jobs, is followed by the proposition of a branch and bound method. It optimizes production plans within a single shift in order to minimize the late work, i.e. the amount of work executed after a given due date. Based on results of computational experiments, conclusions are formulated on the efficiency of the B&B algorithm and on the behavior of FMS under consideration.

A note on the two machine job shop with the weighted late work criterion

The paper presents a dynamic programming approach for the two-machine nonpreemptive job-shop scheduling problem with the total weighted late work criterion and a common due date

Late work minimization in flow shops by a genetic algorithm

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