الفهرس 
Chapter One: Introduction and Problem DefinitionOnly 14 pages are availabe for public view
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Abstract
This thesis is interesting in the optimization of resources of make-to-order manufacturing systems. The main importance of this system is reducing total production costs by reducing the total inventory to get nearly zero inventory and then reducing the material handling. In this work, a kind of manufacturing system is studied, called a hybrid flow shop (HFS). The HFS is a flow shop with unrelated parallel machines in each stage. This type of shop can be found in many industries like steel manufacturing, nails and nuts, electronic industries … etc.
This work focuses on studying two different HFS systems. The first system is an HFS with unrelated parallel eligible machines with independent setup times and variable sublot sizes. The size of the sublots varies according to the machines’ speed among different stages. The second is a special case of the first one. It consists of one machine at stages proceeds the final stage while the final stage has unrelated parallel machines.
The main contribution of this thesis is to study the effect of machines’ speed on the sizes of the sublots as the sublot sizes vary according to the machine speed throughout the stages. The researchers also study the effect of machine configuration, that is to say, the different machine distributions in each stage- the machine setup time effect, and the problem size effect on the HFS system.
Mixed-integer nonlinear programming is used to model the two problems of two systems to get an optimum make-span as an objective of the study.
A comparative study is developed between the proposed models and benchmarking case studies to verify the models’ results. The outcomes show that the proposed models are superior to the benchmarking contextual analyses.
Also, four factors are chosen to study their effect on the system by using the ANOVA test. The factors are machines` configuration, which shows the arrangement of machines in each stage, setup times, number of jobs, and the maximum number of sublots.
Finally, the mathematical model is used to solve the optimization problems in the nail company to minimize the makespan of the shop.