الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis considered the problem of layout of facilities with special
emphasis on the implementation of re-layout projects resulted from
the optimization procedure of the pairwise exchange. A multiple
objectives function is incorporated into the solution procedure which
consists of the value of reduction in materials handling costs and an
economic variable of capital and outlay required for implementing
the re-layout projects. The function is formulated to maximize the
project return which is the economic balance of the gain in handling
cost by maximizing the reduction of cost value and the minimization
of the capital outlay required for the re-layout project. Five policies
are considered to test five different cases of the layout problem.
Policy # 1 and policy # 2 were developed before where policy # 3, #
4 and # 5 are proposed. The policies have different concepts and
methodologies to handle the layout problem:
Policy # 1:
This policy selects interchanges which minimize the total material
handling cost and then proceeds to identify interchanges which
maximize the project return. This policy implies that selection of
improved layout would only be based on the associated value of
Total Material Handling Cost TMHC. Project return is calculated for
each layout and then layouts which maximize the project return are
only been considered.
Policy # 2:
This policy identifies interchanges based on the maximization of the
project return at each iteration, i.e. the structure of the objective function includes the re-Iayout costs and therefore selection of
improved layouts is based on the optimization of the function.
Usually the function is structured to maximize the project return.
Policy # 3:
The re-Iayout project is identified based on the initial and [mal
arrangement of the layout. This policy assumes that the whole set of
exchanges required for the project re-Iayout is implemented in the
same time as one re-Iayout project. In this policy the procedure
operates the Steepest Descent Exchange Routine SDER and
identifies the pairs of exchanges based on the minimization of
material handling cost.
Policy # 4:
This policy calculates the project return in accordance to the
sequence of sub-projects which are identified by the multiple
objective function and formulated from the final layout. The subprojects
which consists of more than three facilities is to be divided
into sub-projects each has three facilities.
Policy # 5:
This policy calculates the project return at each sub-project and then
find the maximum of project return. This means that this policy
selects the sub-project which achieves the maximum value of the
project return. The new assignment obtained by carrying out the
aforementioned sub-project is considered as initial assignment.
A procedure for identifying the re-Iayout project is also proposed.
The project which consists of more than 3 facilities is divided to sub-
project each with 3 facilities. This concept is proposed to account for
the practicality of implementing the re-Iayout projects.Five different test case studies are used to evaluate the performance
of the proposed policies. Results indicate that the maximum project
return is attained at the minimum cost of handling. However, there
exist in some cases more than one maximwn.
Policy # 5 which is proposed here can be considered the most
suitable policy to be adopted in implementing the re-Iayout projects
for:
a- It accounts for multiple objectives function to develop projects.
b- It considers the concept of dividing projects to sub-projects each
with at most three facilities. Thus it takes the practical way to
carryout these projects into consideration.
c- It ensures a maximum possible values of project return at each
sub-project. Accordingly time constraints to schedule projects
or sub-projects is relaxed.
d- It gives better results than other policies especially that of
implementing re-layout projects in one go without the
consideration of practical situation.
e- It has logic concepts acceptable to industrial engineers.
Results of the cases are discussed and conclusions are drawn.