A two level branch and bound algorithm is developed to solve an altered form of the standard flow-shop scheduling problem modeled as a bilevel programming problem. The flow-shop scheduling problem considered here differs from the standard problem in that operators are assigned to the machines and each operator has a different time table for the jobs on each machine. The shop owner is considered...

This paper provides an application oriented analysis of local search procedures for Operation Scheduling and Shop Floor Management of a major German manufacturer of cigarette machines. The heuristics applied are the Thresholdand Simulated Annealing-Algorithm considering Job Shop as well as embedded FMS production features. In this context a new neighbourhood search technique is developed, which...

Job shop scheduling problems occurs in automobile industry, aerospace industry, printing industry, and chemical industry. Job shop scheduling problems are real world and complex. The present work assesses the effect of change in setup times levels on make span, maximum flow time and maximum tardiness measures. The model of the job shop is developed in PROMODEL simulation software. Three levels ...

Two scheduling methods based on Extreme Value Theory (SEVAT) and Genetic Algorithms (GA) are developed. The SEVAT approach is a schedule building approach that creates a statistical profile of schedules through random sampling and predicts the potential' of a schedule alternative. The GA approach, on the other hand, is a schedule permutation approach, in which a population of schedules are init...

One of the basic and significant problems, that a shop or a factory manager is encountered, is a suitable scheduling and sequencing of jobs on machines. One type of scheduling problem is job shop scheduling. There are different machines in a shop of which a job may require some or all these machines in some specific sequence. For solving this problem, the objective may be to minimize the makesp...

The flexible job shop scheduling problem (FJSP) is a generalization of the classical job shop scheduling problem that allows to process operations on one machine out of a set of alternative machines. The FJSP is an NP-hard problem consisting of two sub-problems, which are the assignment and the scheduling problems. In this paper, we propose how to solve the FJSP by hybrid metaheuristics-based c...

The use of random test problems to evaluate algorithm performance raises an important, and generally unanswered, question: Are the results generalizable to more realistic problems? Researchers generally assume that algorithms with superior performance on diÆcult, random test problems will also perform well on more realistic, structured problems. Our research explores this assumption for the per...

This paper presents a multi agent system for the job shop scheduling problems. The proposed system consists of initial scheduling agent, search agents, and schedule management agent. In initial scheduling agent, a modified Shifting Bottleneck is proposed. That is, an effective heuristic approach and can generate a good solution in a low computational effort. In search agents, a hybrid search ap...

In previous work we introduced a simple constraint model that combined generic AI strategies and techniques (weighted degree heuristic, geometric restarts, nogood learning from restarts) with naive propagation for job shop and open shop scheduling problems. Here, we extend our model to handle two variants of the job shop scheduling problem: job shop problems with setup times; and job shop probl...

Due to the complicated circumstances in workshop, most of the conventional scheduling algorithms fail to meet the requirements of instantaneity, complexity, and dynamicity in job-shop scheduling problems. Compared with the static algorithms, dynamic scheduling algorithms can better fulfill the requirements in real situations. Considering that both flexibility and fuzzy processing time are commo...