• Journal of the Korean Statistical Society
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• v.28 no.4
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• pp.523-533
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• 1999

We consider the M/G/1 queueing model with D-policy. The server is turned off at the end of each busy period and is activated again only when the sum of the service times of all waiting customers exceeds a fixed value D. We obtain the distribution of unfinished work and show that the unfinished work decomposes into two random variables, one of which is the unfinished work of ordinary M/G/1 queue. We also derive the distribution of queue waiting time.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.143-146
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• 2001

본 연구는 생산-운송시스템에서 수요자와 생산시설 및 운송네트워크이 주어질 경우 최소의 비용으로 고객을 지원할 수 있는 시스템의 결정을 위한 GIS(Geographic Information System) 기반의 차량 운송시스템의 연구이다. 주요 결정 변수는 생산공장의 위치, 운송네트워크, 운영할 창고 및 재고유지수준 등이 포함된다. 본 연구에서는 다-품목 생산 및 공급문제를 비 선형문제로 정식화하고 이를 선형문제로 변환하여 정수계획문제(IP)로 해를 구하였다. 이를 위한 전산 프로그램을 개발하고 예제들을 응용하고 그 결과를 보였다.

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.721-732
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• 2008

A single server infinite capacity queueing system with Poisson arrival and a general service time distribution along with repeated attempt and server vacation is considered. We made a comprehensive analysis of the system including ergodicity and limiting behaviour. Some operating characteristics are derived and numerical results are presented to test the feasibility of the queueing model.

• Proceedings of the Korean DIstribution Association Conference
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• 2003.02a
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• pp.109-120
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• 2003

As the logistics industrial environment becomes more complex and its scale becomes increase, the vehicle fleet scheduling system has become recognized the necessity as a major strategy in the logistics field. The vehicle fleet scheduling system is computerized package that find the vehicle routes and schedules to accomplish the required service to customers using vehicles. This paper introduces the state of the art of vehicle fleet scheduling system in Korea and foreign country and the future research subject are presented.

• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.181-193
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• 1992

This paper shows the model of a consecutive-k-out-of-n :G system with common-cause outages. The objective is to analytically derive the mean operating time between failures for a non-repairable component system. The average failure time of a system and the system availability are also considered. Then, the model is extended to a system with repairable components and unrestricted repair, in which service times are exponentially distributed.

• Journal of Distribution Research
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• v.4 no.1
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• pp.31-49
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• 1999

The present paper discusses the current status of outsourcing of service encounter in department stores. We attempt to find if there is any significant relationship between outsourcing motive and business performance. The 30 department stores under analysis show that they vary in the degree to which they appreciate the necessity of outsourcing and also the which they employ outsourcing. It is also found that firm size influences the portion of outsourcing. The two main motives of outsourcing seem to be (i) cost saving and (ⅱ) better customer satisfaction. We find that the latter plays a more important role. However, there seems to be no significant connection between outsourcing and performance and between motives of outsourcing and performance.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.314-321
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• 1998

This paper presents motion based design methodology for structures. Current design methodologies are primarily strength-based. Such methods are adequate when strength is expected to govern the design. But as the slenderness of structures increases, motion such as displacement and acceleration becomes the dominant criterion. In this paper, a preliminary design approach for beam-type buildings, where motion dominates the design, is discussed by effectively distributing the magnitude of structural stiffness to control the distribution of displacement under service load. This analytic development is illustrated using a cantilever beam as the structure under static loads, free vibration, and forced vibration.

• Journal of Korean Institute of Industrial Engineers
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• v.16 no.1
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• pp.107-114
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• 1990

A queueing system with compound Poisson arrival and server vacation is analyzed by including supplementary variables. We consider a vacation system in which the server leaves for a vacation as soon as the system empties. When he returns, if no customer is waiting for service, he waits until a group of customers arrive and then begins to serve. We obtain the system size distribution and the waiting time distribution. Additional performance measures will be also considered.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.487-488
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• 2007

Fault section detection and service restoration is very important in ungrounded distribution system. Techniques currently used to track down faults are time consuming and cumbersome. A new scheme is developed based on communication technology, and the simulation result shows that the method can satisfy the requirement proposed.

• Journal of Distribution Science
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• v.10 no.12
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• pp.25-34
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• 2012

Purpose - This study examines college students' perceived choice attributes in traditional markets and the relationship quality. We study the relationships between attributes that common people look for while choosing a store (e.g., product, service, advertising, and atmosphere), consumption emotion, consumer's value, and relationship quality. Research design, data, methodology - In order to verify the relationship between choice attributes and relationship quality, and moderating (i.e., consumption emotion) and mediating effects (i.e., customer value), we collected data from 202 consumers in Gyeonggi province to test the theoretical model and its hypotheses. For this purpose, this study, utilized an empirical methodology. Results - First, contrary to the previous research findings involving college students, this study observed that four factors of store choice attributes at a traditional market were important to consumers in heightening the relationship quality. Specifically, product (β = .608, p < .01), service (β = .351, p < .01), advertising (β = .237, p < .01), and atmosphere (β = .425, p < .01) are significantly related to relationship quality. Second, consumers selected product (β =. 521, p < .01) as the most important attribute. Atmosphere (β = .254, p < .01) and service division (β = .148, p < .05), in this order, are the other important factors in this regard. However, advertising (β = -.112, p = .100) is not statistically significant. To improve and develop the relationship quality with consumers, traditional markets should ensure supply of suitable products and goods, improve store atmosphere by modernizing facilities, and educate merchants to improve their services. Third, the results of the moderating effects, although marginally statistically significant, suggest that for the consumers with low consumption emotion for traditional markets, an affirmative experience of products and store atmosphere heightens their values. In addition, the consumers having low consumption emotion who could promote consumer values were found to improve and develop a marginally significant relationship quality. Finally, the study revealed that the consumer's value exhibited a complete mediation effect in the relationships between service and relationship quality, and advertising and relationship quality and a partial mediation effect in the relationships between product and relationship quality, and atmosphere and relationship quality. Conclusions - Consumer satisfaction is important to increase the competitiveness of traditional markets, and products and store atmosphere are important attributes to increase the relationship quality. Specifically, merchants should supply different products, modernize their facilities, and improve store atmosphere to compete in traditional markets. In addition, traditional markets should provide value and competitive prices to attract consumers, and should maximize the consumer's value and promote the consumption emotion. Traditional markets should evolve to accommodate changes in the consumer's value and invest in not only functional elements but also symbolic elements.