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The purpose of this paper is to design a model of the port performance metrics for improving the quality in ports by integration of six sigma and system dynamics (SD) approach.

The port performance is measured by the sigma value (SV), the process capability indices (PCIs), and the cost of poor quality (COPQ) as the performance metrics. A port is a complex system that requires SD as an appropriate tool to simulate the model dynamically. The performance metrics focus on measuring the port performance in the entire flow of material in the cargo handling process.

With this model, the changing of the SV, the PCIs, and the COPQ can be identified and analyzed the results to improve the performance in ports. These metrics are utilized to eliminate “waste” in the cargo handling process at ports. This waste consists of lost and damaged cargo, equipment and transporter breakdown, and equipment and transporter delay time. The port performance metrics model can assess the causal relationships in ports as a complex system.

Studies on integration between the six sigma model and SD in ports are few and relatively limited. The port’s performance can be measured directly using the SV, the PCIs, and the COPQ in the simulation. The port performance metrics model will give the decision makers to make some scenarios to contribute for the optimization of performance in ports.

This purpose of this paper is to investigate the location problem of supermarkets, feeding by material the mixed model assembly lines using tow trains. It determines the number and the locations of these supermarkets to minimize transportation and inventory fixed costs of the system.

This is done using integer programming model and real genetic algorithm (RGA) in which custom chromosomes representation, two custom mating and two custom mutation operators were proposed.

The performance of RGA is very good since it gives results that are very close or identical to the optimal ones in reasonable CPU time.

The study is applicable only if a group of supermarkets feed the same assembly line.

For the first time in supermarket location problem, limitation on availability of some areas for possible supermarkets ' locations and capacity of the supermarkets were taken into consideration.