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 paper we study the resource-constrained project scheduling problem with weighted earliness-tardiness penalty costs. Project activities are assumed to have a known deterministic due date, a unit earliness as well as a unit tardiness penalty cost and constant renewable resource requirements. The objective is to schedule the activities in order to minimize the total weighted earliness-tard...

Two single machine scheduling problems with fuzzy processing times and fuzzy due dates are considered. In both we define the fuzzy tardiness of a job in a given sequence as a fuzzy maximum of zero and the difference between the fuzzy completion time and the fuzzy due date of this job. In the first problem we minimize the maximal expected value of a fuzzy tardiness and in the second we minimize ...

The objective of this paper is to propose a scheduling problem for multiple automated guided vehicles (AGVs) in a manufacturing system. Considering the due date of AGVs requiring for material handling among shops in a job shop layout, their earliness and tardiness are significant in satisfying the expected cycle time and from an economic view point. Earliness results in AGVs waiting and tardine...

A new type of tardy cost, called stepwise tardiness, is considered in a single machine problem. The stepwise tardiness scheduling has been found in many practical situations. To the best of our knowledge, there exist few studies directly addressing the problem. In this paper, we develop a heuristic for the single machine total stepwise tardiness (SMTST) problem. In addition, a variable neighbor...

This paper considers a scheduling problem for a single burn-in oven in the semiconductor manufacturing industry where the oven is a batch processing machine with restricted capacity. The batch processing time is set by the longest processing time among those of all the jobs contained in the batch. All jobs are assumed to have the same due date. The objective is to minimize the sum of the absolu...

In this paper, we address the problem of load selection and pickup-dispatching of multiple-load AGVs. Various load-selection rules and pickup-dispatching rules are proposed and studied. The objective of this study is twofold. We want to understand not only the performance of load-selection rules and pickup-dispatching rules in two performance criteria—throughput and tardiness, but also the effe...

This paper describes a constraint programming approach to solving a scheduling problem with earliness and tardiness cost using a problem specific search procedure. The presented algorithm is tested on a set of randomly generated instances of the job shop scheduling problem with earliness and tardiness costs. The experiments are executed also for three other algorithms, and the results are then ...

The unrelated parallel machine scheduling (PMS) problem is essential for the manufacturing industry. Scheduling will save company resources, especially time management. By solving problems quickly and precisely, can get more profit. On that note, this paper focused on PMS problems, which did not consider inherent uncertainty in processing set up by minimizing makespan tardiness. This aimed to m...

Four heuristic algorithms are developed for solving the generalized version of tardiness flow shop problems. We consider the generalized tardiness flow shop model with minimization of the total tardiness as its performance measure. We modify the concept of cost over time (COVERT) for the generalized version of the flow shop tardiness model and employ this concept for developing four algorithms....