• Journal of the Korea Society for Simulation
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• v.25 no.3
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• pp.117-123
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• 2016

This paper presents inference methods for inner operations of a multi-server queue when historical data are limited or system observation is restricted. In a queueing system analysis, autocorrelated arrival and service processes increase the complexity of modeling. Accordingly, numerous analysis methods have been developed. In this paper, we introduce an inference method for specific situations when external observations exhibit autocorrelated structure and and observations of internal operations are difficult. We release an assumption of the previous method and provide lemma and theorem to guarantee the correctness of our proposed inference method. Using only external observations, our proposed method deduces the internal operation of a multi-server queue via non-parametric approach even when the service times are autocorrelated. The main internal inference measures are waiting times and service times of respective customers. We provide some numerical results to verify that our method performs as intended.

• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.120-138
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• 2002

In order to carry out TQM and 6 Sigma management, it is the key elements to make clear a goal and a mission. Above all, we can succeed In achieving a dramatic change and a great outcome only when we make clear the method, incentives, organization and plans under the clear objective. In order to secure the competitiveness against the external challenge, it is essential to keep the several crucial factors such as CEO's will, the systematic process to measure and manage, monitoring to satisfy customer's needs and an aggressive development of TQM activity to encourage the endeavour of the relentless enhancement, and also a positive effort Is to be made for evaluating all quality culture like training experts internally by an outstanding training program under CEO's firm leadership. This study is carried out to understand that which features and factors of success can exist in a company culture if a company accepts a theoretical basis and concept, the general of TQM and 6 Sigma which are one of a management strategy, and carries out TQM and 6 Sigma for achieving improvement of quality and customer's satisfaction.