• 한국컴퓨터정보학회논문지
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• 제11권2호
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• pp.285-294
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• 2006

분산 환경에서 다중 사용자간의 협력 작업을 효과적으로 지원하는 협력 작업에 대한 요구가 급격하게 증가하고 있다. 이러한 협력 작업은 그룹 통신 기술, 분산 처리 기술 등의 다양한 기술적 사항들이 해결되어야 하며, 협력 작업 응용이 갖는 공통적인 요구 사항들이 많이 존재하므로 응용을 개발할 때마다 이러한 요구 사항들을 중복하여 개발하는 것은 많은 개발 비용이 소요되며 중복 투자되는 부분이 많게 된다. 따라서, 협력 작업 응용이 공통적인 요구 사항들과 응용을 보다 경제적으로 개발할 수 있는 체계적인 개발 환경이 필요하다. 이 연구에서는 기존의 이동 에이전트의 조정 모델을 협력 작업응용에 적합하도록 개선한 계층형 역할 기반 조정 모델을 제안하고, 이를 이용해서 이동 에이전트 기반 협력 작업 응용을 위한 개발환경을 설계한다. 계층형 역할 기반 조정 모델은 이동 에이전트들의 다층형 그룹 개념을 제공하고, 각각의 그룹별로 효과적인 조정 정책 구현을 가능하게 하며, 그룹 단위 별로 역할을 부여해서 효과적인 협력 작업 응용 개발을 지원할 수 있다.

• 한국통신학회논문지
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• 제29권9A호
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• pp.1075-1082
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• 2004

무선랜은 우선으로 근거리 디바이스들을 연결하는 통신기술로 IEEE 의 802.11 이 대표적인 프로투콜로 사용되 고 있다 IEEE 802.11 에서 정의된 DCF (Distributed Coordination Fun 이 ion) 는 사용 4 가 증가하고 부하가 커질수록 전송률 ,throughput) 과 데이터 손실률 -(drop rate) 이 커지는 단점을 가지고 있다. 본 논문에서는 무선랜 환경에서 효율적인 최소 동적윈도우 (CWmin) 의 적용을 통한 성능향상방법을 제안하고 분석과 시율레이션을 통해 제안하는 방법이 기존 DCF 보다 성능이 향상됨을 입증한다. 제안하는 동적최소윈도우 방법은 우선 스테이션의 개수가 증가 할수록 , 무선네트워크에 걸리는 부하가 커질수록 성능향상정도가 더욱 커지게 된다. 따라서 향후 고밀도 무선랜 환경에서 효과적일 것이라 기대된다.

• 전자공학회논문지B
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• 제29B권11호
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• pp.36-45
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• 1992

A numerical trajectory planning method for path-constrained trajectory planning is proposed which ensures collision-free and time-optimal motions for two robotic manipulators with limited actuator torques and velocities. For each robot, physical constraints of the robots such as limited torques or limited rotational velocities of the actuators are converted to the constraints on velocity and acceleration along the path, which is described by a scalar variable denoting the traveled distance from starting point. Collision region is determined on the coordination space according to the kinematic structures and the geometry of the paths of the robots. An Extended Coordination Space is then constructed` an element of the space determines the postures and the velocities of the robots, and all the constraints described before are transformed to some constraints on the behaviour of the coordination-velocity curves in the space. A dynamic programming technique is them provided with on the discretized Extended Coordination Space to derive a collision-free and time-optimal trajectory pair. Numerical example is included.

• Industrial Engineering and Management Systems
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• 제8권4호
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• pp.213-220
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• 2009

A revenue sharing contract is one of the mechanisms that coordinate decision makers in a decentralized supply chain toward the consensual goal. The transfer prices between different echelons in the supply chain influence the total supply chain profits. The study aims to explore various transfer pricing heuristics on the supply chain coordination in terms of the supply chain profits and their interactions with the revenue sharing rate. A model is proposed for formulating the collaborative production and distribution planning in a decentralized supply chain with the revenue sharing mechanism. Experiment results indicate that the transfer price and the revenue sharing rate affect significantly the coordination. Among the studied pricing heuristics, the variable-cost pricing method led to the best SC profits. Raising the revenue sharing rate reduced the SC profits no matter what heuristics were employed. Furthermore, the experiments provide us clues for finding the optimal transfer price for the supply chain.

• 한국경영과학회지
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• 제26권4호
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• pp.23-37
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• 2001

This paper is concerned with the critical issue of allocating limited corporate resources among multiple products and between production and marketing functions of a functionally decentralized firm where the two geographically remote functions independently make decisions pertaining to their own decision-making domain. We attempt to demonstrate how IT can contribute to enhancing the quality of coordinating production and marketing functions from the perspective of resource allocation. To this end, we propose a prototype named ITBCS (IT-Based Coordination System) that works under LAN supported computing environments. We develop a comprehensive coordination scheme that can handle various cost functions for the resource constrained, multiple product case that huts been tittle discussed in literature. A preliminary version of ITBCS has been implemented for a hypothetical situation where LAN electronically wires distributed marketing and production computing nodes. Managerial implications are also discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.629-631
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• 2005

The DASPRO (Protection Coordination Program for DAS) is one of the application programs for Distribution Automation System (DAS) of the KEPCO. Application programs developed by KEPCO provide optimal operation in distribution network. The DASPRO includes diverse functions to operate network as construction of database using existing information. creation of diagram for protection coordination. calculation of fault current. evaluation network. power quality monitoring, etc. The DASPRO can examine validity of setting values for protective devices by comparing to T-C curves. Unless the protection coordination is correct, the most suitable setting value for protection devices are displayed on the screen. In this paper, I will introduce the contents of the DASPRO.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2005년도 e-Biz World Conference 2005
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• pp.261-266
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• 2005

Web services provide an effective means to carry out coordinated transactions between multiple, independent business parties. While there are several specific protocols currently being discussed to address the coordination of web services-enabled business transactions, we consider the tentative hold protocol (THP) that allows the placement of tentative holds on business resources prior to actual transactions in order to provide increased flexibility in coordination. In this paper, we present a formal coordination framework for applying THP in conjunction with 2PC to the problem in which service providers independently manage resources and clients seek to acquire the resources from multiple providers as a single atomic transaction. The proposed framework facilitates the performance optimization of THP through effective parameterization with the notion of overhold size and hold duration. The simulation results show that the proposed adaptive approach yields a significant improvement over other non-adaptive policies.

• Journal of Communications and Networks
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• 제13권4호
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• pp.339-344
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• 2011

Base station coordination has received much attention as a means to reduce the inter-cell interference in cellular networks. However, this interference reducing ability comes at the expense of increased feedback, backhaul load and computational complexity. The degree of coordination is therefore limited in practice. In this paper, we explore the trade-off between capacity and feedback load in a cellular network with coordination clusters. Our main interest lies in a scenario with multiple fading users in each cell. The results indicate that a large fraction of the total gain can be achieved by a significant reduction in feedback. We also find an approximate expression for the distribution of the instantaneous signal to interference-plus-noise ratio (SINR) and propose a new effective scheduling algorithm.

• STI Policy Review
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• 제5권2호
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• pp.96-121
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• 2014

This study identifies and evaluates inter-ministerial coordination for developing digital content technology in Korea and Japan. It is conducted through a comparative analysis between Korean and Japanese governmental organizations and their decision making process. Media content had been regulated or promoted by ministries involving culture in both countries. The digitalization of traditional media, however, blurred boundaries between the cultural, technological, and industrial spheres, so ministries involving science and technology, economy and trade, or foreign affairs started to promote digital content technology in the late 1990s. This has been the cause of conflicts among ministries and sometimes led to policy duplication, which in turn weakens policy effectiveness. The competition and coordination of ministries and agencies can be seen through establishing or amending related laws, organizations, and programs. Structural holes are founded in the networks drawn among governmental agencies in charge of digital content, particularly in the field of intellectual property in Korea and online distribution technology in Japan.

• PNF and Movement
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• 제15권1호
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• pp.13-25
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• 2017

Purpose: This study investigated the coordination and contribution of body segments during functioning. Methods: The relevant literature related to body segments and function were reviewed. Results: Efficient control of function is considered with regard to a participant's ability to perform a sequence of movements in body segments, which progresses from the head to the arm, trunk, pelvis, and leg segments. Each segment performs a specific role, which environment explorer using visual information for the head, reaching and grasping for the arms, a stabilizer for the trunk, and the distribution of COM in the pelvis and leg. Conclusion: During any of the movements, the momentum generated by the proximal segments is transferred to the adjacent distal segments in an appropriate sequence. In assessing function for clinical intervention strategies, the segment coordination, segment sequence, transfer of the center of body mass, asymmetrical ratio, muscle activity, and compensatory strategies should be considered.