Research On Shop Scheduling Of A Plastic Base On The Genetic Algorithms

On the condition that the production cost not increasing in the factory,a good shop scheduling plan is the most effective way to shorten the production cycle,to advance the delivery time,and to improve customer satisfaction.With the rapid development of commodity economy,the multi-item and small-batch production mode,and the customer-oriented buyers market has been formed.Finding a good shop scheduling is important not only for China’s medium and small-sized enterprises to seek long-term development,but also for satisfying customer needs and standing out in the global competition.Over the years many experts and scholars put forward lots of shop scheduling methods and theories,but there has not been formed a prototyping scheme to solve the problem of the shop scheduling yet So making a research on shop scheduling plan is of great significance.CY Company is a Hong Kong-funded enterprise which produces disposable plastic film.The main technology of the company include blowing film,printing,bag making,etc.The company takes the flexible flow-shop:each process contains many machines in parallel.The flexible flow-shop scheduling problem is a generalization of the flow-shop scheduling problem.At present,the PMC Department of CY Company still uses backward manual plan according to the experience.This scheduling plan can neither meet the demand of company development nor make customers satisfied with the company’ s product cycle.This paper takes production system of C Y Company as research object Through the investigation on the factory,this paper analyses the production,the technology,the planning and the scheduling to find the scheduling problem in the factory.The paper chooses the vest bag shop scheduling which is representative to establish the mathematical model that targeting with minimizing the maximum flow time.The paper compares the advantages and disadvantages of several kinds of scheduling algorithms,and choses the genetic algorithms as the optimization algorithm.The paper describes methods and theory of genetic algorithms,designs vest bag shop scheduling using genetic algorithms,and then uses MATLAB software to make necessary simulation calculation.The result shows that the simulation production scheduling of vest bag shop reduces 6.99 days than actual on the 10th batch,and the production cycle is shortened by 15%.The simulation result proves the feasibility of the method.At last,the optimization scheduling is used to trial run in the vest bag shop scheduling,proved that the scheduling is of good practical value.