Abstract: This paper considers a bi-criteria scheduling on parallel machines in fuzzy environment which optimizes the weighted flow time and maximum tardiness. The fuzziness, vagueness or uncertainty in processing time of jobs is represented by triangular fuzzy membership function. The bi-criteria problem with weighted flow time and maximum tardiness as primary and secondary criteria, respectiv...

This paper gives the positive answer to the question posed in the title for a wide class of minimization criteria including the maximum completion time, maximum lateness , total completion time, total weighted completion time, total tardiness, total weighted tardiness, number of late jobs and the weighted number of late jobs. That is any scheduling problem for m identical parallel machines to m...

In this paper we consider the bicriteria problem of scheduling n jobs on two parallel machines to minimize the primary criterion of maximum tardiness (1 .!9 ) and the secondary criterion of number of tardy jobs (NT). Algorithms are developed to optimize each of these criteria. Some properties on which the 1 .!9 algorithm is based are developed. Computational experience with the algorithms is al...

A fully polynomial time approximation scheme (FPTAS) with run time O( n m εm−1 ) is developed for a problem which combines common due window assignment and scheduling n jobs on m identical parallel machines. The problem criterion is bottleneck (min-max) such that the maximum cost, which includes job earliness, job tardiness and due window size costs, is minimized.

In this article, we consider the minimization of the total tardiness in a flexible job-shop. In our knowledge, this criterion is not previously studied for this type of shop configuration. The total tardiness criterion was mainly considered in the single machine problem (Chu [Chu92] and Souissi et al. [SKC04]). Few references studied this criterion in a job-shop configuration. The priority rule...

Quality control lead times are one of most significant causes of loss of time in the pharmaceutical and cosmetics industries. This is partly due to the organization of laboratories that feature parallel multipurpose machines for chromatographic analyses. The testing process requires long setup times and operators are needed to launch the process. The various controls are non-preemptive and are ...

In this note we provide new complexity and algorithmic results for scheduling inventory releasing jobs, a new class of single machine scheduling problems proposed recently by Boysen et al. We focus on tardiness related criteria, while known results are concerned with inventory levels between fixed delivery points. Our interest is motivated by the fact that deciding whether a feasible schedule e...

This paper considers sequencing situations with due date criteria. Three di erent types of criteria are considered: the weighted penalty criterion, the weighted tardiness criterion and the completion time criterion. The main focus is on convexity of the associated cooperative games.