الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
One of the basic and significant NP-hard problems, that a shop or a factory manager encounters, 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 makespan. After optimizing the makespan, the jobs sequencing must be carried out for each machine.
A case study extracted from practical scheduling is given to show the feasibility of the modeling method. Comparison with some previous work shows that our model is more compact and effective in finding the best solution.
The above problem can be solved by a number of different methods such as heuristic methods, genetic algorithms, simulated annealing, and machine learning methods for solving such problems. In this work, a new model is presented to work out job shop scheduling problems with the objective of minimizing makespan. The model has been built by using Petri Net technique coded and solved by a special programming language. The structure of this language is based on the network modeling. After modeling the scheduling problem, the model is verified and validated. Then the computational results are presented and compared with other results obtained by other methods. Finally, the model output is analyzed.
The thesis covers all these subjects in five chapters.
Chapter one introduces a brief literature review on most of researchers efforts in the field of job shop scheduling .
Chapter two introduces a short review and fundamental concepts of Petri Net for the required background. Including its descriptions, properties, and analysis methods.
Chapter three focuses on job shop scheduling, identifying its types, objectives, and different techniques.
Chapter four introduces a case study for a job shop problem. In the first part of this chapter the problem was solved and scheduled by means of all the dispatching rule as one of heuristic methods, and in the second part Petri Net technique was applied. Then a comparison between the two methods is presented.