Fuzzy Analysis Of Time-limit And Its Application In Production Scheduling System

The enterprise is in a dynamic system. To ensure the system run excellently, the enterprise has to consider the diversified conditions which affect the system, for instance, the machine maintenance, the machine malfunction, the urgent unit insertion, outside postponement etc. There are some other uncertain factors in the system, for example, the dynamic state and randomness of environment, the sudden change of processing program, the nonrigorous processing time of each task, and sometimes the machine will run in fault. In the actual production dispatch uncertain factors generally make the dispatch not be able to execute under the scheduled plan. All these concrete instances in practice make the problem of schedule complex, and make the problem- solving more difficult. Therefore, for the sake of reflecting the actual production better, improving the enterprise's production benefit; a more effective method to adjust the schedule of enterprise has to be employed. It can make the enterprise adapt to the change of inside and out side environment, and re-schedule rapidly.This program is the sub-program of "The multi-category and small-batch scheduling model and its optimizing algorithm" which is sponsored by the scientific research fund of Department of Education of Jiangsu Province; and also is a sub-program of Nanjing Yangtze Petrochemical Maintenance and Installation Co., LTD's "Producing Schedule Decision Support System's development and its application". This thesis is to solve the under-advanced production and management mode of Nanjing Yangtze Petrochemical Maintenance and Installation Co., LTD, to improve the work efficiency of the shop production; and to make a more feasible method in theory to solve the sorting problem of Job-Shop.The problem of Job-Shop process scheduling is impossible to find optimum solution in theory, so the problem can only be solved with satisfaction answer or near optimum solution. And in the Job-Shop process schedule problem, because of the existing uncertain factors, usually can not be accurately predicted the time that the work needs, but the range of time by experience can be forecasted in general. Therefore, this thesis discusses how to integrate the fuzzy analysis of the time-limit with the heuristic algorithms to find the Job-Shop schedule under existence of the uncertain factors. To help the decision-maker adjust the resource and find satisfactory schedule, the corresponding parameters have been submitted.Using method of fuzzy analysis of the time-limit, this thesis discusses how to develop "Fuzzy Production Schedule Decision Support System" with the Windows 2000 Advanced Server and PowerBuilder9.0. The system design, function composing and the simulating processing have been analyzed in detail. Then with the programming tools the transform from manual work to computer-aided scheduling is realized. Applying different optimization methods for different optimization goals( Fmax, Tmax, Cmax ), and incorporating with flexible controlling technology, and reengineering technology to improve system workability ,the manufacture process can be reorganized. In this thesis application of the SMS in the system improves the instantaneity and work efficiency of the system.Finally, practical examples from Nanjing Yangtze Petrochemical Maintenance and Installation Co., LTD production process 'Technique Regulations' with such system are given and operated in simulation. The result of Algorithm proves the feasibility and reasonableness of adopting the Algorithm in such system.