Study On Job-Shop Scheduling System Based On MES

MES(Manufacturing Execution System) is a management information system for the workshop layer, which lies in the production manufacturing process between the upper layer of enterprise management systems and the lower layer of industrial control systems. It provides workshop managers with real-time information about product planning, product tracing resource allocation and so on. It monitors the production process and maintains the production process in operation. MES is a bridge that spans and fills up the gap between the planning systems and direct industrial controls. It is an effective tool for the management and workshop floor control.Production scheduling is an important part of MES, which directly affect efficiency, operation and management in production. Effective scheduling can reduce cost and improve competitiveness, thereby enhance the competitive advantage of the enterprise. Production scheduling is a typical combinatorial optimization problems, Studying it has both practical significance and theoretical value.This paper analyzed the characteristics of discrete manufacturing enterprises, introduced manufacturing executive system's position in an enterprise and its function. The relevant principles of production scheduling's concepts, problem categorization, characteristic and some typical scheduling algorithms were analyzed at the same time. This paper proposed a structural design of a production scheduling system based on MES, it also elaborates on the system's requirement analysis, the layered structure, the work flow and so on. A model of two layer scheme of production arrangement and production control has been presented.Because of the slowness and complexity of the classical production scheduling algorithms, this paper brought forward a new optimization scheme based on rule. This scheme divides the scheduling process into a primary process and an optimization process. According to the workshop situation, the paper determines the optimization goal, which is achieving shortest completion time. A mathematical model about production scheduling is established through correlation restraints, and a suitable first scheduling rule is selected. We could obtain the production plan after two stages. Through analysis and comparison of examples, this algorithm is proven to be effective. It can run quickly and yield satisfactory results.This paper analyzes and designs production scheduling system by means of the object-oriented method. The paper gives the system's static model and dynamic model, and designs system's functional module. And based on ASP.NET platform, a scheduling prototype system has been developed with some including scheduling functions.