Application of tabu search, TS, to solve a flow shop scheduling problem with changeover times in operations: A case study

2024-01-19T13:03:34+00:00

Flow Shop Scheduling (FSS) Problems are NP-hard combinatorial optimization problems. It is quite difficult to achieve an optimal solution for FSS problems with mathematical modelling approaches because of its NP-hard structure. Tabu search (TS), a mega-heuristic algorithm, plays a major role in searching for near-optimal solutions for NP-hard optimization problems. This paper develops a TS model for solving a FSS problem with the objective to reduce total weighted tardiness time, and constraint on changeover time in operations. The performance of the TS model is compared with that of traditional EDD heuristics, being used. The result shows that the objective value has been reduced by 43%, from 215.95 to 123.07 (h). It indicates that the TS model is a good approach for FSS problems.

Applying fuzzy theory to develop linguistic control charts The pLCC model

2024-03-30T09:32:19+00:00

This paper studies an approach to use fuzzy set theory and possibility theory to construct control charts – a very important on-line process control tool used in quality control. The control chart is constructed based on linguistic data. The model aims to control the process simply and effectively. The quality characteristics are modeled by fuzzy variable. The status of quality characteristics is modeled by triangle fuzzy number. Fuzzy arithmetic is used to calculate the control chart’s center line. The control chart’s control limits are constructed according to Shewhart’s principle. The fuzzy variable’s standard deviation is calculated by a model developed by Kauffman and Gupta.

BOHR International Journal of Operations Management Research and Practices

Application of tabu search, TS, to solve a flow shop scheduling problem with changeover times in operations: A case study

Applying fuzzy theory to develop linguistic control charts The pLCC model