• 한국정보통신학회논문지
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• 제17권5호
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• pp.1101-1105
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• 2013

정적 스펙트럼 관리 방식 아래에서 스펙트럼의 낮은 이용 효율을 개선하기 위하여 다양한 종류의 동적 스펙트럼 접속 방식이 제안되어 왔다. 동적 스펙트럼 접속 방식 중 하나인 myopic 방식은 즉각적인 처리율을 최대로 하는 방식으로 복잡하지 않고 단순하면서도 효율적인 것이 장점이다. 본 논문에서는 myopic 방식의 매체 접속 지연 시간의 분포를 포화 트래픽 환경에서 분석하고, 이를 이용하여 포화 상태가 아닌 정상 상태에서의 시스템 지연 시간을 구한다. 이러한 분석 방법과 결과는 이차 사용자의 실시간 트래픽에 대한 지연 성능 보장을 위한 자료로 사용될 수 있다.

• 산업공학
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• 제17권4호
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• pp.450-458
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• 2004

S-Distribution Center supplies parts to three plants of K-automobile manufacturing company. Since the three plants employ the JIT production system, it is important for S-Distribution Center to deliver small quantities of parts frequently and quickly on time. This paper presents a case study on the improvement of order-picking operation in S-Distribution Center. The study is focused on the reductions of move time and waiting time by redesigning the parts storage location, picking-order terminal location, retrieval policy, and equipment operation policy. The proposed operation system for S-Distribution Center is evaluated through a simple computation analysis and computer simulation. Furthermore, the reducible numbers of equipment and order pickers are investigated by performing a sensitivity analysis.

• 무역학회지
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• 제47권3호
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• pp.191-209
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• 2022

Whether or not insurance policies are securities has been debated for nearly a century. The position of claiming that an insurance policy has securities properties is premised on the concomitant nature of the maritime cargo insurance policy to the bill of lading. However, in reality today, marine cargo insurance policies are transferred between parties involved in international trade as an integral part of the bill of lading, and the two securities go through the same distribution process. The issue of recognizing the securities properties of an insurance policy is particularly debated when the insurance policy is issued in a order or bearer form. In a normal insurance policy, the name of the right holder, such as the claimant, is written on the insurance policy, and it is not usually transferred by endorsement. In principle, insurance policies are interpreted as neither securities nor negotiable securities. Sometimes, research is being done on legal reform to respond to digitalization of securities, and bills of lading are the subject of research. If marine cargo insurance policies, which are sometimes premised on distribution, have securities properties, the status of the regulations on digitization of bills of lading currently being studied may be helpful for digitization of marine cargo insurance policies. Under these circumstances, the securities of marine cargo insurance policies are reviewed based on recent practices.

• 유통과학연구
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• 제20권2호
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• pp.11-18
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• 2022

Purpose: The purpose of this paper is to investigate the influence of brand equity on customer purchase decision (CPD) of products for retailers distribution (RB) in Ho Chi Minh city, Vietnam. There are five elements in the brand equity model such as brand awareness, brand association, brand loyalty, perceived quality, and pricing policy. Research design, data and methodology: Qualitative methodology was used for exploring the research model and variables. The survey was conducted to collect data from 251 respondents who bought products at RB in Ho Chi Minh city, which is based on a Likert scale. The collected data were analyzed with the reliability of the scale, exploratory factor analysis, and research hypothesis testing by SPSS 22. Results: The results obtained revealed that brand awareness, brand association, perceived quality, and pricing policy have a significant impact on CPD for RB. Furthermore, the results showed that perceived quality is the most significant component in influencing CPD at retailers. Conclusions: From the research results, some management implications that RB should focus on are perceived quality, choice of pricing policies and strategies, brand building and development to attract more customers as well as enhance its image to improve customers' purchasing decisions of products at retail distributors chain.

• 유통과학연구
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• 제20권8호
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• pp.115-121
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• 2022

Purpose: This article aims to explore the distribution of technological innovation and environmental policy challenges to respond to COVID-19. The study also attempts to tackle a paradigm shift in science and technology policies against the pandemic and a desirable direction for environmental policies. The COVID-19 pandemic has been the one that rapidly changed global people's lifestyle. For the spread of a terrible infectious disease could not be avoided, regardless of a highly industrialized society. Research design, data and methodology: This study basically employs a qualitative approach as a methodology. This study is based on the fact that environmental pollution, various natural disasters continuously occur, and there are many unforeseeable parts, despite remarkable development of scientific technology, and that the circumstances are becoming more complex. Results: This study noted that scientific technology civilization formed due to industrial revolutions can deteriorate environment and increase environmental threat factors. As an alternative to this, this study investigates alternative discussions on how the 4th Industrial Revolution can help scientific technology and human environment to harmoniously coexist and develop. Conclusions: It implies that this study focuses on the possibility of overcoming this crisis through science and technology innovation, although mankind is in crisis of COVID-19 due to excessive human development.

• Journal of the Korean Statistical Society
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• 제25권1호
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• pp.111-122
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• 1996

A model for a system whose state changes continuously with time is introduced. It is assumed that the system is modeled by a Brownian motion with negative drift and an absorbing barrier at the origin. A repairman arrives according to a Poisson process and repairs the system according to an (s,S) policy, i.e., he increases the state of the system up to S if and only if the state is below s. A partial differential equation is derived for the distribution function of X(t), the state of the system at time t, and the Laplace-Stieltjes transform of the distribution function is obtained by solving the partial differential equation. For the stationary case the explicit expression is deduced for the distribution function of the stationary state of the system.

• 통상정보연구
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• 제8권4호
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• pp.343-368
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• 2006

The rapid expansion of regionalism has resulted in the creation of blocs of the global economy, so that those countries not belonging to one or more blocs can be discriminated. The purpose of this paper is to examine the competition policy theoretically, international background with issues, and discussion trend of global enterprise. By doing them, this paper suggests the responsive plan, future prospects, and policy directions for the competition policy by distribution service. There is not a statistically significant relationship between international diversification strategy and firm performance. However, we observed some tendency that the larger the firm size, the higher the firm performance, assuming the degree of international diversification or multinationality to be constant. However, the export productivity increase after 1~2 years, and there exits a clear evidence that the innovation investment increases a firm's export competitiveness as time goes on.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권4호
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• pp.280-286
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• 2016

Purpose: Recently, Jiang defines the tradeoff B life to minimize a sum of life lost by preventive maintenance (PM) and corrective maintenance (CM) contribution parts and sets up an optimal replacement age of age replacement policy as this tradeoff life. In this paper, Jiang's model only considering the known lifetime distribution is extended by assigning different weights to two parts of PM and CM in order to reflect the practical maintenance situations in application. Methods: The new age replacement model is formulated and the meaning of a weight factor is expressed with the implied cost of failure under asymptotic expected cost model and also discussed with one-cycle expected cost criterion. Results: The proposed model is applied to Weibull and lognormal lifetime distributions and optimum PM replacement ages are derived with corresponding implied cost of failure. Conclusion: The new age replacement policy to escape the estimation of cost of failure in classical asymptotic expected cost criterion based on the renewal process is provided.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권1호
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• pp.340-367
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• 2018

Storage services integration can be done for achieving high availability, improving data access performance and scalability while preventing vendor lock-in. However, multiple services environment management and interoperability have become a critical issue as a result of service architectures and communication interfaces heterogeneity. Storage federation model provides the integration of multiple heterogeneous and self-sufficient storage systems with a single control point and automated decision making about data distribution. In order to integrate diverse heterogeneous storage services into a single storage pool, we are proposing a storage service federation framework named BoxBroker. Moreover, an automated decision model based on a policy-driven data distribution algorithm and a service evaluation method is proposed enabling BoxBroker to make optimal decisions. Finally, a demonstration of our proposal capabilities is presented and discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권5호
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• pp.2379-2397
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• 2017

Content distribution technology, which routes content to the cache servers, is considered as an effective method to reduce the response time of the user requests. However, due to the exponential increases of content traffic, traditional content routing methods suffer from high delay and consequent inefficient delivery. In this paper, a content selection policy is proposed, which combines the histories of cache hit and cache hit rate to collaboratively determine the content popularity. Specifically, the CGM policy promotes the probability of possible superior paths considering the storage cost and transmission cost of content network. Then, the content routing table is updated with the proportion of the distribution on the paths. Extensive simulation results show that our proposed scheme improves the content routing and outperforms existing routing schemes in terms of Internet traffic and access latency.