Papers by Author: Le Cao

Abstract: The measurement of worker differences is fundamental consideration in personnel assignment which is one key decision that influences the productivity and quality of assembly production. Due to the weakness of presented researches on worker differences measurement, the concept of station fitness, which takes the worker skill level and accumulated execution time in a given period as parameters, is proposed to better describe the worker competency and provide a way of measuring the differences among workers. A personnel assignment optimization model based on station fitness for assembly production is constructed, and the objectives are maximizing the station fitness for each assembly station and minimizing the difference of station fitness for workers assigned in the same assembly line. Then a heuristic algorithm based on the fitness matrix is presented to solve this model. The results from the example demonstrate the feasibility of the approach.

Abstract: With the characteristic analysis of manufacturing process in various manufacture enterprises, Model Driven Architecture methodology is applied to construct dynamic reconfigurable manufacturing process model, which can solve the problems of portability, information integration, and interoperability effectively. A dynamic reconfigurable modeling process framework based on model driven Architecture is introduced for manufacture enterprises in this paper. It separates the manufacturing system functionality specification from its implementation on any specific technology platform, and makes the system reconfigurate the manufacturing progress through the transformation of models and transmission of information. At last, the integrated system was applied to a discreet manufacturing process and the application result proves that the system is practical and effective.

Abstract: Cell formation is one of the key issues in cellular manufacturing research. A two-stage cell formation method is proposed. With this approach, parts are first clustered into different groups based on similarity factor; then, machines are assigned to these part groups according to the principle of maximum machine utility. Examples show that the proposed method is feasible in grouping parts and machines into cells so that machine utilization and manufacturing systems efficiency are improved.

Abstract: Cell formation which involves grouping similar parts into part families and the corresponding machines into machine cells is one of the key research issues for designing cellular manufacturing system. Functionally identical machines may vary in production performance. In the paper, processing cost is employed to differentiate the performance of machines, and a two-stage cell formation approach for manufacturing systems with multiple functionally identical machines is proposed. With this approach, parts are firstly clustered into part groups based on process similarity; secondly, machines are then assigned to part groups according to their performance to form manufacturing cells. A heuristic algorithm based on process similarity is presented for part group identification, and a mathematical model with the objective of minimizing the total processing cost is established. An example is employed to illustrate the benefit of the proposed approach and the results suggest that the proposed approach is feasible.

Abstract: Cell formation, which involves grouping similar parts into part families and the corresponding machines into machine cells, is one of the key research issues for designing cellular manufacturing system. In this paper, a mathematical model which targets at maximizing the machine utilization and similarity of the part groups is built. A heuristic algorithm based on clustering analysis is proposed. An example is employed to illustrate the benefit of the approach and the results suggest that the proposed approach is feasible.