Chen Qing-xin

Resource model and service match algorithm for mould manufacturing grid

This paper integrates characteristics of the mould manufacturing industry with grid computing technologies and proposes the concept of mould manufacturing grid. In order to realise sharing and collaboration of manufacturing resources, a commonly unified resource model is needed to support expandability. Manufacturing service demands are classified into three different levels from a business point of view. Manufacturing services and grid nodes can then be divided correspondingly. Part and process features are used in describing service demands from the viewpoints of customers and production plans of manufacturers. The resulting unified meta-data model is based on the object-oriented concept. A standard and expandable resource model is established and a service match algorithm is developed based on service features. A simulation prototype of a mould manufacturing grid is demonstrated.

Simulation Optimization of Manufacturing System Including Assemble Lines and Material Handling Systems

Customized equipment manufacturing enterprises use cellular manufacturing system, material handling system transfer material between the units. It is difficult to obtain this type of manufacturing system accurate solution of optimization problem by traditional mathematics methods. This paper establish simulation model about process-assemble and material handling system based on computer simulation. Because the model has much variable and coupling influence, this paper uses sensitivity analysis method based on orthogonal experiments, determines the parameters optimization direction and the influence discipline between parameters, proposes a heuristic optimization method based on the optimization goal and practical constraints. Analysis shows that the proposed optimization method, which can be effective and reasonable configuration enterprise resources.

The Prediction of Mould Project Duration Based on Recursive Network

The critical path method (CPM) is often used to make the project plan and predict the project duration in mould manufacturing projects. For generating manageable networks, the CPM networks assume that networks are directed without loops. So in CPM, recursive works are ignored. But in actual mould manufacturing, reworking of tasks are frequent and inevitable, and then they will result in project delaying. So the planned project duration is often less then the actual one. The paper added the loops in the CPM network, and created the prediction model of the duration based on reworking using the Markov chains and solved the probabilities of the mould project duration.

Knowledge Hierarchical Induction for Injection Mould Repairs Based on Fuzzy Rough Set

High accuracy of the description to injection mould repair schemes is required and excess inducted rules are obtained when the knowledge is inducted by Pawlak rough set,therefore,the feasibility of the conventional rough set in practical application is poor.By the combination of feature and concept hierarchy model and the definition of innovation about concept,the hierarchical representation of repair schemes and knowledge is put forward.The repair schemes can be reconstructed hierarchically by the calculation of innovation about concept which represents the fuzzy description of them and then feature decision tables are achieved.By the abstraction of innovation about concept from the feature decision tables,feature fuzzy similar matrix is constructed and the feature decision table is divided into some fuzzy equivalent subsets by introducing confidence level vector.The algorithm of feature reduction and knowledge induction based on fuzzy rough set is put forward by defining single or multiple fuzzy feature equivalence relations.A case study indicates that the feasibility of this method and the universality of the inducted knowledge are both prompted obviously.