ChenGuang Liu

Seru Seisan‐ an innovation of the production management Mode in Japan

Summary Seru Seisan, also called “beyond lean” in many Japanese manufacturing industries, is an innovation of the production management mode in Japan. Although an increasing number of manufacturing enterprises in Japan have been adopting this strategy with great success, it is not popular among manufacturing enterprises and researchers out of Japan. This paper provides a brief introduction of Seru Seisan to promote the strategy worldwide. First, a report on the origin of Seru Seisan and an analysis on its generation background are provided. Second, the differences between Seru Seisan and the conventional cell production are shown. The characteristics, advantages, and disadvantages of Seru Seisan are also investigated. A summary of the Seru modalities that appear during its evolution is presented as well. Finally, several key problems for further research on Seru Seisan are presented.

Uncertain association rule mining algorithm for the cell formation problem in cellular manufacturing systems

Although data mining has enjoyed popularity in recent years with advances in both academia and industry, the application of data mining to cellular manufacturing, one of the most powerful management innovations in job-shop or batch-type production, is still under-utilized. Based on association rule mining, Chen initially developed a cell formation approach. One problem of such a cell formation algorithm is that various real-life production factors were ignored. In this paper we propose a new cell formation algorithm by way of uncertain association rule mining. The proposed algorithm incorporates several key production factors, such as operation sequence, production volume, batch size, alternative process routings, cell size, the number of cells, and the path coefficient of material flow. The efficacy and efficiency of the proposed algorithm were tested using several numerical problems.

Formation of independent manufacturing cells with the consideration of multiple identical machines

Cellular manufacturing is a manufacturing philosophy with the goal to produce low-medium volume products with high variety, while maintaining the high productivity of large-scale production. It is recognised as one of the most powerful management innovations in job-shop and batch production. Among the problems of designing a cellular manufacturing system, cell formation is the central and foremost issue. In the present paper, we investigate the formation of independent manufacturing cells with the consideration of multiple identical machines, in which inter-cell movements are completely eliminated by allocating identical machines in different manufacturing cells. Incorporating many real-life production factors including processing time, set-up time, alternative processing routes, machine capacity, batch size and cell size, we formulate a bi-objective mathematical model to minimise workload imbalance among manufacturing cells. Then, a genetic algorithm based on non-dominated sorting genetic algorithm II is developed to solve it. The computational results of numerical examples and the comparison analysis validated the performance of the proposed algorithm.

Product architecture, product development process, system integrator and product global performance

In this article, we characterise the impact of product global performance on the choice of product architecture during the new product development (NPD) process. We classify product architectures into three categories: modular (neither interface is geometrically nested) integral (all interfaces are geometrically nested) and hybrid (some, but not all interfaces are geometrically nested). Existing studies show that the choice of a product architecture during the NPD process is a crucially strategic decision for a manufacturing firm. However, no single architecture is optimal in all cases, thus analytical models are required to identify and discuss specific trade-offs associated with the choice of the optimal architecture under different circumstances. This article develops analytical models that obtain a products global performance through a modular/hybrid/integral architecture. Trade-offs between costs and expected benefits from different product architectures are analysed and compared. Multifunction products and small size are used as examples to formalise the models and show the impact of the global performance characteristics. We also investigate how optimal architecture changes in response to the exogenous costs of system integrators. Some empirical implications obtained from this study show that if the global performance benefit is sufficiently large, then modular architecture is an absolutely sub-optimal decision and integral architecture is an all-the-time candidate for optimal architecture.

A multi-skilled worker assignment problem in seru production systems considering the worker heterogeneity

Abstract The flexibility of production systems is becoming more and more important for manufacturers facing various changes. As an effective way to increase the flexibility in a short time with a small investment, multi-skilled workers have received more attention in recent years. In this paper, a multi-skilled worker assignment problem is solved in the context of seru production systems, in which differences in workers’ skill sets and proficiency levels are taken into consideration. Worker grouping, cell loading, and task assignment are solved concurrently in the problem. A mathematical model with objectives of improving the inter-seru and inter-worker workload balance is proposed to solve the problem. In order to verify the proposed model, a numerical example is presented and solved by a sum weighted method. Due to the NP-hard nature of the model, a meta-heuristic algorithm based on NSGA-II is developed. The algorithm is tested by several numerical examples and the impact of differences in workers’ competency on workload balance is analyzed based on the computational results.

A Cell Formation Algorithm Incorporating Multiple Practical Production Factors

Numerous cell formation methods were designed to minimize the cost of the material flows between cells. However, most of them do not simultaneously take various production factors under consideration. In this paper, multiple key real-life production factors, namely production volume, batch size, alternative process routing and perfect coefficient of each routing, cell size, unit cost of intercell/intracell movement, and path coefficient of material flows are considered. Since the considering problem is NP-complete, a three-stage heuristic algorithm is developed to obtain the approximate solutions. The proposed algorithm comprise three stages: 1) initially group the machines according to the alternative process routings of each part. 2) select the appropriate process routing of each part with respect to the over-all material movement cost, and 3) regularly form cells based on the chosen appropriate process routing. A simple numerical example and an industrial case are used to test the computational performance of the proposed algorithm. The test results imply that it is useful in generating cell configurations in both quality and speed.

The Complexity of Algorithms Computing Game Trees on Random Assignments

The complexity of algorithms for computing game trees on random assignments has been given substantial attention in the literature. In this line, we investigate the complexity of algorithms that compute a special class of game trees

Management of overlapped cross-training: with or without a supervisor?

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An Algorithm for the Design of Manufacturing Cells

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Generalization of Complexity Oscillations in Infinite Sequences

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