• 제목/요약/키워드: Complete network

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파장 라우팅 WDM망에서의 파장 경로 설정 방식 (A Wavelength Path Accommodation Method in Wavelength Routed WDM Network)

  • 김병재;박진식;신기수
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (3)
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    • pp.636-638
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    • 1998
  • WDM망을 구성하는데 있어서 광학적 파장은 가장 중요한 자원의 하나이다. 그러나 주어진 통신 요구를 모두 수용하면서 동시에 최소한의 파장만을 사용하는 WDM망의 설계 문제는 이미 NP-complete 계열의 문제인 것으로 밝혀졌으며 많은 휴리스틱 알고리즘들이 제안되었다. 본 논문에서는 임의의 물리적 망 위상(topology)과 완전 연결(full connection)형태의 통신 요구가 주어질 경우, 요구되는 파장 경로(Wavelength Path, lightpath)를 확립하기 위한 방법으로써 각 노드 사이의 최단 거리 경로를 기반으로 하여 탐색 공간을 만들고 구성된 탐색 공간 내에서 Branch-and-bound 탐색방식을 수행하는 파장 경로 설정 알고리즘을 제안한다. Branch-and-bound탐색방식은 초기에 좋은 bound조건을 가질 경우 주어진 시간 안에 보다 넓은 탐색 공간을 검색할 수 있으므로 최초의 탐색에서 가능한 좋은 성능의 파장 경로 설정을 발견할 수 있어야한다. 시뮬레이션 실험을 통하여 최초의 탐색에서 발견한 파장 경로 설정과 구성된 탐색 공간내의 최적해를 얻고, cut-set를이용하여 요구 파장 개수의 하위 한계값을 계산한후, 이를 상호 비교하여 제안된 알고리즘의 성능을 평가한다.

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Delay-Constrained Bottleneck Location Estimator and Its Application to Scalable Multicasting

  • Kim, Sang-Bum;Youn, Chan-Hyun
    • ETRI Journal
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    • 제22권4호
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    • pp.1-12
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    • 2000
  • Designing a reliable multicast-based network that scales to the size of a multicast group member is difficult because of the diversity of user demands. The loss inferences of internal nodes by end-to-end measurements do not require the use of complete statistics because of the use of maximum likelihood estimation. These schemes are very efficient and the inferred value converges fast to its true value. In the theoretical analysis, internal delay estimation is possible but the analysis is very complex due to the continuity property of the delay. In this paper, we propose the use of a bottleneck location estimator. This can overcome the analytical difficulty of the delay estimation using the power spectrum of the packet interarrival time as the performance metric. Both theoretical analysis and simulation results show that the proposed scheme can be used for bottleneck location inference of internal links in scalable multicasting.

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T cell costimulation by CD28, CTLA-4, and ICOS

  • Lee, Kyung-Mi
    • IMMUNE NETWORK
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    • 제1권2호
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    • pp.95-103
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    • 2001
  • T cells play a central role in the initiation and regulation of the immune response to foreign antigens. Full activation of T cells requires the engagement of T cell receptor complex (TCR) and the binding of a second costimulatory receptor to its ligand expressed on antigen presenting cells (APC). Among the molecules known to provide costimulatory function, CD28 has been the most dominant and potent costimulatory molecule. However, the function of CD28 is becoming more complex due to the recent discovery of its structural homologue, CTLA-4 and ICOS. This review summarizes the biology and physiologic function of each of these receptors, and further focuses on the biochemical mechanism underlying the function of these receptors. Complete understanding of the CD28/CTLA-4/ICOS costimulatory pathway will provide the basis for developing new therapeutic approaches for immunological dieseases.

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물류정보기술의 전략적 활용과 기업성과 (A Study on the Strategic Utilization of Logistics Information Technology and Business Performance)

  • 이충배;박희수
    • 통상정보연구
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    • 제3권1호
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    • pp.177-196
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    • 2001
  • The advancement of information technology provides a wide range of options for the corporate to cope with new business environments. As with most other businesses, the utilization of the logistics information technology can be an instrument to enhance the competitiveness of the company. Therefore it is essential to analyze how companies utilize and verify the relationship between company business performance and the level of information technology utilization, which is the objective of this paper. The questionnaire was sent to 300 companies listed on the stock market at random The author received 176 responses of which 142 were complete and valid. According to the analysis of questionnaires, the adoption level of information technologies was dependent on the perception of top managers on the importance of information technology in business competitiveness. Furthermore the level of relation between the information technology adoption and business performance was significant. Therefore businesses need to increase the utilization of information technologies, such as establishment of logistics information system, network with other business partners in order to business logistics performance.

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Korean Mistletoe (Viscum album Coloratum) Extract Induces Eel (Anguilla japonica) Non-specific Immunity

  • Yoon, Taek-Joon;Park, Kwan-Ha;Choi, Sang-Hoon
    • IMMUNE NETWORK
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    • 제8권4호
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    • pp.124-129
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    • 2008
  • Background: The immunomodulatory effects of Korean mistletoe (Viscum album Coloratum) on the innate immune responses of eel (Anguilla japonica) were studied. Methods: Mistletoe, Freund’s complete adjuvant (FCA), or phosphate-buffered saline (PBS) as a control was injected into eel peritoneal cavities. Results: Nitroblue tetrazolium (NBT)-positive cells in the head kidney of eel were significantly augmented by the second day post-injection of mistletoe. Reactive oxygen intermediates (ROI) were more produced in mistletoe-injected fish kidney leucocytes than in FCA-injected ones. The level of lysozyme activity in the serum of fish 2 days after injection with mistletoe was also significantly higher than that in the serum of the control fish. The optimal concentration of mistletoe in inducing the highest serum lysozyme activity was revealed to 500${\mu}$g/200 g of fish. In phagocytic activity assay, mistletoe-sensitized eel kidney phagocytes captured more zymosan than did the control fish. Conclusion: Korean mistletoe appeared to be a good activator of the non-specific immune responses of eel.

발견적 해법을 이용한 분산 컴퓨터 시스템 설계 (A Heuristic for the Design of Distributed Computing Systems)

  • 손승현;김재련
    • 산업경영시스템학회지
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    • 제19권40호
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    • pp.169-178
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    • 1996
  • Geographically dispersed computing system is made of computers interconnected by a telecommunications network. To make the system operated efficiently, system designer must determine the allocation of data files to each node. In designing such distributed computing system, the most important issue is the determination of the numbers and the locations where database files are allocated. This is commonly referred to as the file allocation problem (FAP)[3]. The proposed model is a 0/l integer programming problem minimizing the sum of file storage costs and communication(query and update) costs. File allocation problem belongs to the class of NP-Complete problems. Because of the complexity, it is hard to solve. So, this paper presents an efficient heuristic algorithm to solve the file allocation problem using Tabu Search Technique. By comparing the optimal solutions with the heuristic solutions, it is believed that the proposed heuristic algorithm gives good solutions. Through the experimentation of various starting points and tabu restrictions, this paper presents fast and efficient method to solve the file allocation problem in the distributed computing system.

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Ethernet Ring Protection Using Filtering Database Flip Scheme For Minimum Capacity Requirement

  • Rhee, June-Koo Kevin;Im, Jin-Sung;Ryoo, Jeong-Dong
    • ETRI Journal
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    • 제30권6호
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    • pp.874-876
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    • 2008
  • Ethernet ring protection is a new technology introduced in ITU-T Recommendation G.8032, which utilizes the generic Ethernet MAC functions. We introduce an alternative enhanced protection switching scheme to suppress penalty in the switching transient, in which the Ethernet MAC filtering database (FDB) is actively and directly modified by information disseminated from the nodes adjacent to failure. The modified FDB at all nodes are guaranteed to be consistent to form a complete new ring network topology immediately. This scheme can reduce the capacity requirement of the G.8032 by several times. This proposed scheme can be also applied in IP protection rings.

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변전소 내 주변압기 사고 발생 시 배전계통 연계점 이동을 통한 복구 알고리즘 (A Restoration Algorithm using Moving the tie Switch in Distribution System in case of Fault Occur in Power system Substation MTR)

  • 홍준호;이승재;최면송;임일형;김태완
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.159_160
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    • 2009
  • In this paper proposes a new algorithm of efficiency outage restoration using a outage load switching to a healthy MTR a fault occurrence at a MTR. In addtion, proposed algorithm includes a outage restoration method which keeps MTR optimal capacity with reorganization of distribution network in case it can not restore outage state loads caused by shortage of healthy MTR remain capacity. In case that proposed sequence still can not complete restoration, this paper suggests a efficiency outage restoration with objective function included priority in outage loads.

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노인.어린이 문화.복지 센터 계획안 (The Planning of Culture Center for The old & The young)

  • 윤지영;신제문
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2006년도 추계학술발표대회 논문집
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    • pp.177-178
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    • 2006
  • This plan is for a different type of welfare facilities devised by analyzing problems with existing welfare centers and focusing on connection with residents and link between culture and welfare and among generations. In terms of re-development plan of Youngsun-2-dong, Youngdo-gu, Busan and the neighborhood under this plan, Youngsun-dong, Youngdo-gu is one of the densely populated districts of the aged, with lower growth rate and poor housing and welfare facilities. However, the district has a blessed natural environment and historical site of cultural relics of the Neolithic Age as well as growth potential as a logistics center with broader network of roads linking with Bukhang Bridge when Namhang Bridge construction is complete, showing the aspiration for change toward hi-tech maritime city in the 21st century of Youngdo-gu. This plan is expected to promote unity between the old and children, protection from social marginalization, and re-socialization education and set the stage for participation and solidarity of residents in the community.

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심전계(ECG)의 제작설계

  • 서병설
    • 대한의용생체공학회:의공학회지
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    • 제9권2호
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    • pp.247-250
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    • 1988
  • Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology.

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