• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.909-910
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• 2012

Shipbuilding is an order made assembly production basically. To build a single vessel, it costs hundreds of thousands small and big parts and million tons of structural steel. From contract to delivery, It takes 2 years of time in general. Shipbuilding parts are supplied order made based in and out of the country. For the cost and efficiency issue, on-time supply of ship parts is critical. Thus, this study suggests the optimum material management system plan of ship components for the best result.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06d
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• pp.311-314
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• 2011

Wi-Fi 메쉬 네트워크는 IEEE 802.11 표준을 기반으로 노트북, 스마트폰 등의 무선 단말에 인터넷 연결을 제공하기 위한 무선 다중 홉 네트워크이다. Wi-Fi 메쉬 네트워크에서는 무선 채널의 방송 특징으로 인해 발생하는 간섭(Interference) 때문에 프레임 충돌 문제가 발생한다. 본 논문에서는 이러한 프레임 간섭을 미연에 방지하는 스케줄링 MAC 프로토콜을 제안한다. 제안하는 방법은 각각의 무선 채널에서 간섭 조건을 만족하는 링크 조합을 결정하고, 이를 통하여 Wi-Fi 메쉬 네트워크의 프레임 전달 수율(Throughput)을 극대화함을 목표로 한다. 시뮬레이션 결과를 통해 본 논문에서 제시하는 스케줄링 MAC 프로토콜이 기존에 알려진 CSMA/CA 기반의 MAC 프로토콜에 비해 수율을 50 % 이상 향상함을 보인다.

• IE interfaces
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• v.25 no.2
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• pp.153-162
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• 2012

The reliability is defined as a probability that a system will operate properly for a specified period of time under the design operating conditions without failure and it has been considered as one of the major design parameters in the field of industries. Reliability-Redundancy Optimization Problem(RROP) involves selec tion of components with multiple choices and redundancy levels for maximizing system reliability with constraints such as cost, weight, etc. However, in practice both active and cold standby redundancies may be used within a particular system design. Therefore, a redundancy strategy(active, cold standby) for each subsystem in order to maximize system reliability is considered in this study. Due to the nature of RROP, i.e. NP-hard problem, A Parallel Particle Swarm Optimization(PPSO) algorithm is proposed to solve the mathematical programming model and it gives consistently better quality solutions than existing studies for benchmark problems.

• Journal of Navigation and Port Research
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• v.31 no.9
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• pp.771-778
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• 2007

A container terminal gate is not only an entrance of containers, but also the first input point of containers' information. Therefore, to achieve the accuracy of container information, there are various containers' numbers recognition methods used. Gate productivity can significantly vary depending upon those recognition methods. Recently, RFID which is one of the u-IT businesses run by the Korean government is under consideration for application to the gate as an automatic system. If RFID is used, it is expected to have both the qualitative benefits through avoiding defects of other systems and the quantitative benefits by improving productivity. Hence, this study aims to provide some insight on the benefits of RFID, and to compare productivity of the existing gate system with the RFID gate system based on computer simulation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.10a
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• pp.5-6
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• 2009

전 세계적으로 온실가스에 대한 관심이 높아지는 가운데 UN 기후변화 협약 발리로드맵에 따르면 2013부터 한국도 온실가스 의무감축대상국에 포함될 예정이다. 최근 녹색성장 위원회의 국가 온실가스 중기 (2020) 감축목표 설정에 대한 3가지 시나리오에 따르면 물류분야에서도 2020년 은실가스 배출전망치 대비 20~30% 감축이 예상된다. 이에 따라 물류효율화에 기반한 온실가스 배출량 및 에너지 사용량 저감과제를 적극적으로 추진해야 한다. 본 논문은 물류부문에서도 항만에 적용가능한 온실가스 감축 기술을 IT 관점에서 접근하여 대안을 제시한 후 이를 종합적으로 관리할 수 있는 탄소배출관리시스템을 개발한다.

• IE interfaces
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• v.24 no.1
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• pp.51-57
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• 2011

The traveling purchaser problem (TPP) is a generalization of the well-known traveling salesman problem (TSP), which has many real-world applications such as purchasing the required raw materials for the manufacturing factories and the scheduling of a set of jobs over some machines, and many others. In the last decade, TPP has received some attention of the researchers in the operational research area. However, all of the past researches for TPP are restricted on a single purchaser (vehicle). It could be the limitation to solve the real world problem. The purpose of this paper is to suggest the capacitated multiple TPP (CMTPP). It could be used in inbound logistics optimization in supply chain management area and many others. Since TPP is known as NP-hard, we also developed the heuristic algorithm to solve the CMTPP.

• Journal of Navigation and Port Research
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• v.32 no.2
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• pp.141-148
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• 2008

This paper is structured into three main parts and a conclusion. The main section provide definitions of efficiency, effectiveness and performance in terms of the distribution channel, followed by a review of related performance measurement, before discussing difficulties of measurement. According to the theoretical approach, it appears that key theroretical issues are centered around customer service, logistics excellence, time compression, the use of IT, and a move towards integrated logistics. The empirical approach shows that in the past, various financial performance indicators were regarded as relevant management information. However, today, management needs additional performance indicators. Therefore, external assessments of effectiveness must be performed to measure customers' satisfaction with the physical flow of product through the distribution channel network. So, what is needed is to take previous normative and explorative research and progress through a framework by developing valid measures of distribution channel's effectiveness and efficiency, and identifying research methodologies suited to the data collection requirements.

• The Journal of Economics, Marketing and Management
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• v.6 no.2
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• pp.29-33
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• 2018

Purpose - This study aims to offer the suggestions for the researches and policies that could be used as important data to effectuate future FTA. The objective of this study is to suggest a direction of Korea that can form a new logistics hub in Northeast Asia. Research design, data, and methodology - This study was conducted in parallel with literature review and empirical studies for the analysis. 180 valid samples were collected from Korean consumers', and qualitative analysis was employed on the satisfaction level of imported goods welfare of Korean consumers. Results - It is expected that Korea and China would experience increased opportunity factors in this area with the growth of economic sphere in Northeast Asian. If existing problems are solved by utilizing regional environment efficiently together, the hub function of Northeast Asia logistics will be advanced. Conclusions - Korea is introducing and operating special economic zones that provide the exception and support for foreign investment. Therefore, it is necessary to monitor the prices of imported goods, so that the exporters can adjust the prices and obtain the unjust profit equivalent to the tariff reduction by grasping the overseas market trends of the imported product prices.

• Korea Trade Review
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• v.45 no.5
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• pp.55-74
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• 2020

This study examines the policy direction and specific countermeasures for addressing possible port labour issues from the perspective of Just Transition which may be raised by closing coal fired power plants in Korea. Current energy transition policy and port labour policy in Korea are reviewed and case studies in the countries which has experienced closure of coal fired power plants are undertaken. Although it varies from country to country, a similar approach was found that the employment problem of coal fired power plant closures and measures based on Just Transition regime to mitigate the negative impacts that occur in the region are the key to successful transition. It is suggested that countermeasures for port labour should be institutionalized for providing stakeholders with legal stability covering labours not only directly employed by the plants but also employed in entities in the whole supply chains.

• Journal of the Korea Safety Management & Science
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• v.26 no.1
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• pp.91-97
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• 2024

When a fire breaks out in a distribution center, it causes a lot of damage. And the most casualties are caused by Fire accidents. Therefore, training for fire prevention should be mandatory at the distribution center. Also, the contents of education should be different in room temperature warehouses and low temperature warehouses. Fire education in low-temperature warehouses should be more emphasized. This is because many fires occur in low-temperature warehouses. In this study, a study was conducted to determine the important order of training hours and contents for fire prevention education according to the type of distribution center. The importance of time and content for safety education in all types of warehouses did not differ significantly. It was first decided that safety prevention training should be conducted periodically in all types of warehouses