• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.240-242
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• 2007

The game theoretic analysis in wireless networks can be classified into the jamming game of the physical layer, the multiple access game of the medium access layer, the forwarder's dilemma and joint packet forwarding game of the network layer, and etc. In this paper, the game theoretic analysis about the multiple access game that selfish nodes exist in the IEEE 802.11 DCF(Distributed Coordination Function) wireless networks is addressed. In this' wireless networks, the modeling of the CSMA/CA protocol based DCF, the utility or payoff function calculation of the game, the system optimization (using optimization theory or convex optimization), and selection of Pareto-optimality and Nash Equilibrium in game strategies are the important elements for analyzing how nodes are operated in the steady state of system. Finally, the main issues about the game theory in the wireless network are introduced.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.445-447
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• 1999

이동호스트를 지원하는 이동네트웍에서의 멀티캐스팅 문제는 빈번한 그룹 멤버쉽의 변화와 함께 그룹 멤버의 위치 변화를 가져와 기존의 고정 호스트를 기본으로 설계된 멀티캐스트 프로토콜을 적용하는 것은 적합하지 못하다. 이런 점에서 특히 Mobile IP를 기본 유니캐스팅 방법으로 사용하는 환경에서 이동호스트를 위한 몇가지 멀티캐스팅 방식이 제시되었으나, 비최적 경로의 데이터 전송, 비효율적인 데이터 중복 전송 또는 빈번한 멀티캐스트 트리의 재구성으로 인한 오버헤드 등의 문제점을 내포하고 있다. 따라서 본 논문에서는 이런 문제점을 좀 더 보완하면서 Mobile IP를 사용하는 이동호스트에게 IP 멀티캐스트를 제공하는 효과적인 프로토콜을 제안한다. 호스트의 이동성을 적극 반영하여 유동적으로 멀티캐스트 포워더(Multicast Forwarder)를 선정함으로서 데이터 전송 경로의 단축, 중복되는 데이터 전송의 감소와 같은 효과를 얻을 수 있고 그 결과를 시뮬레이션을 통하여 확인해 본다.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.11-19
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• 2004

글로벌 물류 환경하에 항공화물포워더는 신속한 배송, 실시간 위치 추적 및 상태관리 등의 복잡 다양해지고 있는 고객의 물류서비스 요구에 대응하기 위해 항공화물포워더들은 '포워더정보시스템(Forwarder Information System, FIS)'을 도입하고 있으나, 기존 포워더 정보시스템들은 단순 내부업무 관리 기능만을 지원하여 화물 수출입 관련 주체들의 정보공유 및 협업 등의 상호연계가 취약한 상태이다. 본 연구에서는 실제 포워더 및 관련 주체 대상 설문조사를 통하여 공급리드타임이 짧으며, 여러 관련주체들의 신속한 정보공유가 필수적인 특성을 지닌 포워더를 중심으로 한 항공물류 공급망을 분석하고, 공급망 관점에서 포워더정보시스템의 문제점 개선을 위해 현행 항공화물포워더의 업무와 포워더정보시스템를 분석하고, 개선방안 제시하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.43-57
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• 1999

Recently, leading edge companies use the Supply Chain Management as a competitive weapon to secure and maintain customer loyalty. As a consequence, they are concentrating resources on the company's core business and employing strategic alliances with third-party providers to ensure the company provides its customers' desired logistics service levels at acceptable costs. Under this circumstances, this paper surveys the third party logistics as a loading edge logistics industry coping with the progress of the supply chain management. The status and the type of the TPL including the Forwarder are analyzed in the view point of global logistics. Also, the development strategy of third party logistics in the future is suggested.

• The Korean Journal of Air & Space Law and Policy
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• v.21 no.2
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• pp.71-96
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• 2006

This paper intends to describe the carrier's duty for the delivery of international air cargo and the carrier's liability for the illegal delivery of cargo under the Montreal Convention, lATA Conditions of Carriage for Cargo and judicial precedents. Under the Article 13 of Montreal Convention, the consignee is entitled, on arrival of the cargo at the place of destination, to require the carrier to deliver the cargo to it, on payment of the charge due and on complying with the conditions of carriage. And unless it is otherwise agreed, it is the duty of the carrier to give notice to the consignee as soon as the cargo arrives. Under the Article 18 of Montreal Convention, the carrier is liable for damage sustained in the event of the destruction or less of or damage to, cargo upon condition only that the event which caused the damage so sustained took place during the carriage by air. And the carriage by air comprises by the period during which the cargo is in the carriage of the carrier. Under the Article 11 of lATA Conditions of Carriage for Cargo, carrier is liable to shipper, consignee of any other person for damage sustained in the event of destruction of loss of, or damage to, or delay in the carriage of cargo only if the occurrence which caused to the damage so sustained took place during the carriage as defined under Article 1. According to the precedent of Korean Supreme Court sentenced on 22 July 2004, the freight forwarder as carrier was not liable for the illegal delivery of cargo to the notify party (actual importer) on the airway bill by the bonded warehouse operator because the freight forwarder did not designate the bonded warehouse and did not hold the position of employer to the bonded warehouse operator. In conclusion, the carrier or freight forwarder should pay always attention the movement and condition of the cargo not to be liable for the illegal delivery of cargo.

• Journal of Distribution Science
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• v.18 no.5
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• pp.99-109
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• 2020

Purpose: This study aims to develop and empirically analyze a research model in order to comprehend the relationship among the service quality of market-wholesaler system, re-transaction intention, and recommendation intention of forwarder. Further, we suggest new six factors reflecting the service quality of market-wholesaler system and highlight market expansion of forwarder as a mechanism in the relationship. Research design, data and methodology: The authors developed the new scales measuring the service quality of market-wholesaler system (i.e. trade price, price fluctuation, payment receipt, settlement period, trade information, and customer service) and conducted a cross-sectional survey for 439 forwarders in a wholesale market. And then we performed a series of path analyses to test hypotheses. The hypotheses are as follows. [H1] The service quality of market-wholesaler system will positively affect forwarders' market expansion, [H2] Forwarders' market expansion will positively affect their re-transaction intention, [H3] Forwarders' market expansion will positively affect their recommendation intention, [H4] Forwarders' re-transaction intention will positively affect their recommendation intention. Results: The results showed that all the six factors for the service quality of market-wholesaler system were positively related to market expansion of forwarders. There was a differential effectiveness in the six factors of the service quality. More specifically, the positive effect of customer service factor was the strongest on market expansion of forwarders. And the respective effects of trade price, price fluctuation, settlement period, trade information factors were followed in order. The positive effect of payment receipt factor was the weakest on market expansion of forwarders. Also, market expansion of forwarders was positively related to their re-transaction intention and recommendation intention. Furthermore, market expansion of forwarders was indirectly related to recommendation intention through re-transaction intention as well. Conclusions: The research findings provide important theoretical and practical implications. This study is the first to attempt to test the perception of forwarders for the service quality of market-wholesaler system by developing and using the new scales. Also, there has been a sharp controversy about the effectiveness of market-wholesaler system. The findings support that market-wholesaler system would be activated by empirically verifying the effectiveness of the service quality on the various outcomes.

• Journal of KIISE:Information Networking
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• v.33 no.4
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• pp.289-298
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• 2006

Algorithms for application-level multicast often use trees to deliver data from the source to the multiple receivers. With the tree structure, the throughput experienced by the descendant nodes will be determined by the performance of the slowest ancestor node. Furthermore, the failure of an ancestor node results in the suspension of the session of all the descendant nodes. This paper focuses on the transmission of data using multiple virtual forwarders, and suggests a scheme to overcome the drawbacks of the plain tree-based application layer multicast schemes. The proposed scheme elects multiple forwarders other than the parent node of the delivery tree. A receiver receives data from the multiple forwarders as well as the parent node and it can increase the amount of receiving data per time unit. The multiple forwarder helps a receiver to reduce the impact of the failure of an ancestor node. The proposed scheme suggests the forwarder selection algorithm to avoid the receipt of duplicate packets. We implemented the proposed scheme using MACEDON which provides a development environment for application layer multicast. We compared the proposed scheme with Bullet by applying the implementation in PlanetLab which is a global overlay network. The evaluation results show that the proposed scheme enhanced the throughput by 20 % and reduced the control overhead over 90 % compared with Bullet.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.229-238
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• 2013

This study was conducted to analyze on the operational cost of logging operations in the whole-tree logging operation system by tower-yarder and swing-yarder, and in the cut-to-length logging operation system by excavator with grapple in order to spread efficient logging operation technique and to establish the logging operation system. In the results of the analysis of operation cost, in case of the whole-tree logging operation system, the operation cost was 2,099 won/$m^3$ in felling by chain saw, 28,286 won/$m^3$ in yarding by tower-yarder, 18,265 won/$m^3$ in yarding by swing-yarder, 18,939 won/$m^3$ in bucking by excavator with grapple and chain saw, 20,484 won/$m^3$ in forwarding and accumulation by wheel type mini-forwarder, 12,701 won/$m^3$ in forwarding and accumulation by excavator with grapple and small forwarding vehicle. In case of the cut-to-length logging operation system, the operation cost was 10,160 won/$m^3$ in felling and bucking by chain saw, 7,567 won/$m^3$ in cut-to-length extraction by excavator with grapple, 6,982 won/$m^3$ in branches and leaves extraction by excavator with grapple, 3,040 won/$m^3$ in the operation road construction by excavator with grapple, 20,484 won/$m^3$ in forwarding and accumulation by wheel type mini-forwarder, 12,701 won/$m^3$ in forwarding and accumulation by excavator with grapple and small forwarding vehicle.

• Journal of Korea Port Economic Association
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• v.31 no.2
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• pp.69-83
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• 2015

This study proposes effective overseas market entry strategies that could allow Korean logistics companies to develop international capabilities and become global firms by adapting to environmental changes in global logistics. First, it reviews the overseas networks of Korean international freight forwarders and the recent trends in the global logistics market. Then, it surveys the conditions of two groups of freight forwarders, namely partnerships and subsidiaries, which are categorized according to type of entry into foreign markets. These companies' networks are concentrated in East and Southeast Asia regardless of network type. As a result, the ability for partnerships to network is higher than that of subsidiaries. However, subsidiaries are small in number and located in various regions because of their initial stage, which is why their businesses depend on the price competitiveness of the parent company. The satisfaction and performance of subsidiaries are both generally low according to the presented findings. In addition, the successful strategies of international freight forwarders include following operations, specializing their logistics services, building collaborations among small and medium-sized companies, recruiting and training professional human resources in international logistics, and entering markets together with their customers. Overall, this study highlights the importance of measuring and evaluating objectively the level and performance of overseas networking through a survey about the internationalization of Korean freight forwarder companies. To conclude, this study is considered to contribute to raising their global competitiveness by suggesting strategies derived from the survey findings and SWOT analysis.

• International Commerce and Information Review
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• v.12 no.1
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• pp.75-95
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• 2010

This paper examined the factors affecting the implementation of information technology in Korean Global Logistics Companies. Nowadays, the spread of electronic commerce using internet demands a large changes doing business with company to company and give that company a change to recognize logistics. To support logistics activity, all kinds of companies are using the computer and are recognized that the efficient using of Cyber Logistics Information will mainly play a roll to strength the companies competition power. We gathered detailed data on our sample companies mainly from publicly available sources : Korea International Freight Forwarder Association (KIFFA), and companies' web sites. A structured questionnaire was used to collect information about: (1) the company (2) To investigate the factors of the three contexts described above on korean Global Logistics companies's electronic trade adoption and implementation. (3) Usage level of electronic logistics. Most of the approximately 70 questions enumerated in the questionnaire were open-ended, which was consistent with our primary objective of developing a conceptual framework that was informed by empirical evidence. This study suggests that top management support and influential power are main factors for the Korean Global Logistics Companies.