In this paper we confront the job shop scheduling problem with total flow time minimization. We start extending the disjunctive graph model used for makespan minimization to represent the version of the problem with total flow time minimization. Using this representation, we adapt local search neighborhood structures originally defined for makespan minimization. The proposed neighborhood struct...

A heuristic algorithm that uses iteratively LPT and MF approaches on different job and machine sets constructed by using the current solution is developed to solve a classical multiprocessor scheduling problem with the objective of minimizing the makespan. Computational results indicate that the proposed algorithm is very competitive with respect to well-known constructive algorithms for a larg...

In this paper we address the problem of makespan optimal sequencing in a ow shop with parallel machines (FSPM). This kind of production facility is a generalization of the standard ow shop where at least one stage consists of two or more identical machines. We present a branch & bound algorithm and its parallel implementation which minimizes the makespan, i. e. the maximum completion time requi...

The effect of workers’ learning curve on production rate in manual assembly lines is significant when producing relatively small batches of different products. This research analyzes this effect and suggests applying work-sharing among the workers in such an environment to improve the time to complete the batch, namely, the makespan. Work-sharing refers to a situation where adjacent workers hel...

This paper presents the development of an alternative method for makespan computation algorithms of a re-entrant flow shop scheduling problem using bottleneck analysis. The computation is specifically intended for the cyber manufacturing centre (CMC) which is an Internet based collaborative design and manufacturing services at Universiti Tun Hussein Onn Malaysia. The CMC processes scheduling re...

In the sequel, we propose a new neighbourhood structure for local search for the fuzzy job shop scheduling problem, which is a variant of the well-known job shop problem, where uncertain durations are modelled as fuzzy numbers and the objective is to minimise the expected makespan of the resulting schedule. The new neighbourhood structure is based on changing the position of a task in a critica...

Lower bounds are typically used to evaluate the performance of heuristics for solving combinatorial minimization problems. In the absence of tight analytical lower bounds, optimal objective-function values may be estimated statistically. In this paper, extreme value theory is used to construct confidence-interval estimates of the minimum makespan achievable when scheduling nonsimilar groups of ...

Given a system model where machines have distinct speeds and power ratings but are otherwise compatible, we consider various problems of scheduling under resource constraints on the system which place the restriction that not all machines can be run at once. These can be power, energy, or makespan constraints on the system. Given such constraints, there are problems with divisible as well as no...

This paper addresses the problems in scheduling a precedence constrained tasks of parallel application with random tasks processing time and edges communication time on Grid computing systems so as to minimize the makespan in stochastic environment. This is a difficult problem and few efforts have been reported on its solution in the literature. The problem is first formulated in a form of stoc...