Results Achieved

The GA model presented in Section 18.6.2 was coded in Microsoft Visual Basic 6.0 using MS Excel as the program interface. The machine used to run the pro­gram was a PC with an Intel Core2 Duo Processor, with 4 GB DDR RAM at '066 MHz. The program was run for a population size of 100 chromosomes, crossover rate of 0.6, and mutation rate 0.2. To track the evolution of fitness function and the rate of convergence, the overall logistics costs (the value of objective function) and its cost components (including production costs, distribu- ^llon costs, and shortage or backordering costs) were recorded at every generation ^f°r 1500 iterations. Table 18.1 shows the achieved results (i.e., the average