The present paper, titled “optimizing the time of preparation, taking into account the timing of   repair and maintenance using non-linear modeling”, has been implemented with the aim of designing and presenting a mathematical model to get the best sequence of operations leading to minimum the total time of production. The main research question is related to the reduction of time and productio...

This paper addresses an unrelated multi-machine scheduling problem with sequence-dependent setup time, release date and processing set restriction to minimize the sum of weighted earliness/tardiness penalties and the sum of completion times, which is known to be NP-hard. A Mixed Integer Programming (MIP) model is proposed to formulate the considered multi-criteria problem. Also, to solve the mo...

Different manufacturing enterprises use regularly scheduling algorithms in order to help meeting demands over time and reducing operational costs. Nowadays, for a better useofresources and manufacturingin accordance withcustomer needs and given the level ofcompetitionbetweencompanies, employing asuitablescheduling programhasa double importance. Conventional productionmethods are constantly subs...

In this paper, we consider the M/G/k queueing system with setup times. This particular queueing model is common in manufacturing systems, where idle machines are turned off to save on operating costs, as well as in server farms, where idle servers are turned off to conserve power. While recent literature has analyzed the M/M/k system with exponential setup times, no closedform solutions were ob...

this paper deals with the single machine multi-product lot scheduling problem in which defective items are produced in any production run of each product. we have adopted the common cycle scheduling policy and assumed that the setup times for production of each product can be non-zero. further, we have assumed that defective items will be reworked and the inspection costs during the normal prod...

In this paper we consider the problem of scheduling jobs on parallel machines with setup times. The setup has to be performed by a single server. The objective is to minimize the schedule length (makespan) as well as the forced idle time. The makespan problem is known to be NP -hard even for the case of two identical parallel machines. This paper presents a pseudopolynomial algorithm for the ca...

Setup operations are significant in some production environments. It is mandatory that their production plans consider some features, as setup state conservation across periods through setup carryover and crossover. The modelling of setup crossover allows more flexible decisions and is essential for problems with long setup times. This paper proposes two models for the capacitated lot-sizing pr...

This paper addresses the two-machine flowshop scheduling problemwith separate setup times to minimize makespan or total completion time (TCT). Setup times are relaxed to be random variables rather than deterministic as commonly used in the OR literature. Moreover, distribution-free setup times are used where only the lower and upper bounds are given. Global and local dominance relations are dev...

This paper presents a novel, integer-linear programming (ILP) model for an identical parallel-machine scheduling problem with family setup times that minimizes the total weighted flow time (TWFT). Some researchers have addressed parallel-machine scheduling problems in the literature over the last three decades. However, the existing studies have been limited to the research of independent jobs,...

In production planning, sequence dependent setup times and costs are often incurred for switchovers from one product to another. When setup times and costs do not respect the triangular inequality, a situation may occur where the optimal solution includes more than one batch of the same product in a single period — in other words, at least one sub tour exists in the production sequence of that ...