Typically, general job shop scheduling problems assume that working times of machines are equal, for instance eight hours a day. However, in real factories, these working times are different because the machines may have different processing speeds, or they may require maintenance. That is, one machine may need to be operated only half day whereas other machines may have to be operated for the ...

    Hub covering location problem, Network design,   Single machine scheduling, Genetic algorithm,   Shuffled frog leaping algorithm   Hub location problems (HLP) are synthetic optimization problems that appears in telecommunication and transportation networks where nodes send and receive commodities (i.e., data transmissions, passengers transportation, express packages, postal deliveries, etc....

This paper proposes a methodology for real-time job-shop scheduling problems. It introduces a new classification of the scheduling methods for JSSPs with emphasis on the search methods and the significance of the search space. Subsequently, a machine-order search space is proposed as a new framework in which different single-machine scheduling algorithms and search methods can be incorporated t...

A batch machine is a machine that can process up to c jobs simultaneously as a batch, and the processing time of the batch is equal to the longest processing time of the jobs assigned to it. In this paper, we deal with the complexity of scheduling an unbounded batch machine, i.e., c = +∞. We prove that minimizing total tardiness is binary NP-hard, which has been an open problem in the literatur...

A hybrid scheduling system of machines and lots was proposed. The system was composed of machine and lot scheduling systems which alternatively operate by an interval time during production. A machine agent corrects its own machine schedule when a process is behind schedule. The agent informs the schedule correction to the previous and next machine agents through peer-to-peer communication. The...

This paper presents a mathematical model for a flow shop scheduling problem consisting of m machine and n jobs with fuzzy processing times that can be estimated as independent stochastic or fuzzy numbers. In the traditional flow shop scheduling problem, the typical objective is to minimize the makespan). However,, two significant criteria for each schedule in stochastic models are: expectable m...

In this paper, scheduling problems in Flexible Manufacturing Cells (FMC) are studied. The scheduling objective is to minimize the makespan. We used a genetic algorithm (GA) for solving the optimization scheduling problem. We have developed one FMC with industrial characteristics with the objective of studying scheduling problems in these types of manufacturing systems (single machine scheduling...