• Journal of the Korean Chemical Society
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• v.54 no.2
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• pp.234-239
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• 2010

Carbonate derivatives were synthesized for the use of diesel additives and the derived cetane numbers of the derivatives were measured. Some carbonate ester derivatives were synthesized from 1,2-glycerol carbonate and long alkyl chain fatty acids. To improve the solubility, we introduced unsaturated groups into aliphatic carbons and alkyl group into ${\alpha}$-carbon to the carbonyl group. The derived cetane numbers obtained from ASTM method were increased up to 1.0, which means some carbonate derivatives could be potential diesel additives.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.595-596
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• 2004

Based on the systems and devices which are being developed in the KNICS project, the data communication network (DCN) which is an essential element for the interfaces among the I&C systems. is designed. The traffic load for each network is calculated at the expected maximum traffic condition. The result shows that the utilizations of all networks satisfy the design requirements.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1983.04a
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• pp.9-12
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• 1983

Local Area Network is a rapidly developing area of interst and activity in the computer field. A.J. Thurber has classified the LAN with 7 categories. We choose two example system among these categories, such as Distributed Computer Network(DCN) and Labolink. In this paper, We propose the Local Area Network of Jeonbuk National University according to the choosen two example.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.149-159
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• 1997

Eleven plots(10m*10m) were established in Pinus densiflora forests and analized in with TWINSPAN and DCA techniques, to study the comparison of the structure of plant community by soil depth in Ulsan Grand Park. As a result of this analyusis, the communities were divided into two groups : Community B which have shallow one. Community A showed climatic climax which have proceeded from Pinus densiflora to Quercus variabilis, Castanea crenata, Platycarya strobilacea, and at last to Carpinus laxiflora. Community A showed climatic climax which have proceeded fro, Pimus densiflora to Quercus variabilis, Castanea crenata, Platycarya strobilacea, and at last to carpenus laxiflora. Community B showed edaphic climax in sere of Pinus desiflora. The diffrernce of the growth of tree height was showed significantly between two communities. The sample tree aged 30 in Community A was 8.50m high and the sample tree aged 35 in Community B was 3.80m high. Community A was better than Community B in soil characteristics and species diversity indicies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.6
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• pp.2964-2985
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• 2019

Global data center IP traffic is expected to reach 20.6 zettabytes (ZB) by the end of 2021. Intra-data center networks (Intra-DCN) will account for 71.5% of the data center traffic flow and will be the largest portion of the traffic. The understanding of traffic distribution in IntraDCN is still sketchy. It causes significant amount of bandwidth to go unutilized, and creates avoidable choke points. Conventional transport protocols such as Optical Packet Switching (OPS) and Optical Burst Switching (OBS) allow a one-sided view of the traffic flow in the network. This therefore causes disjointed and uncoordinated decision-making at each node. For effective resource planning, there is the need to consider joining the distributed with centralized management which anticipates the system's needs and regulates the entire network. Methods derived from Kalman filters have proved effective in planning road networks. Considering the network available bandwidth as data transport highways, we propose an intelligent enhanced SDN concept applied to OBS architecture. A management plane (MP) is added to conventional control (CP) and data planes (DP). The MP assembles the traffic spatio-temporal parameters from ingress nodes, uses Kalman filtering prediction-based algorithm to estimate traffic demand. Prior to packets arrival at edges nodes, it regularly forwards updates of resources allocation to CPs. Simulations were done on a hybrid scheme (1+1) and on the centralized OBS. The results demonstrated that the proposition decreases the packet loss ratio. It also improves network latency and throughput-up to 84 and 51%, respectively, versus the traditional scheme.

• Journal of the Korean Society for information Management
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• v.36 no.3
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• pp.203-228
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• 2019

This study developed KISTI CLCM, a curation model suitable for the content life cycle, focusing on the KISTI Content Curation Center. For developing the KISTI Curation Model, the previously developed models DCC, DCC&U, UC3 and DCN models were reviewed and the advantages of the models connected to the mission and tasks of the digital curation center were derived. Interviews with staffs of the KISTI Content Curation Center identified the characteristics of the content and identified the level of achievement of the current task. In addition, this study proposed to enhance usability by developing KISTI content curation waves based on the UC3 model to discover user-centered services and add new values to digital resources.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.457-460
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• 2009

본 논문에서는 실제 모델의 인테나 성능을 측정해 효율과 이득 면에서 더 나은 새로운 인테나 패턴을 설계하여 제작하였다. Ansoft사의 HFSS 시뮬레이션 툴을 사용하여 기존 모델의 3중대역(CDMA/DCN/PCS) IFA안테나를 4중대역(CDMA/GSM/PCS/WCDMA)으로 전류상쇄를 최소화 하여 설계하였다. 그 결과 기존 모델보다 평균 효율은 약 8.3 % 개선시켰으며, 평균 이득은 0.82dB 향상 되었다.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.445-448
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• 2003

During a time when cellular systems are being deployed in massive scale worldwide, international roaming is becoming increasingly important. This paper presents UIM (User Identification Module) for mobility support, authentication, and service portability between different mobile systems. We also introduce network model based on PASM(Portable Authentication and Mobility Service Machine) which will support signaling protocol and user information conversions with database for roaming between different mobile networks. Stored data types and elements in UIM, logical data structure and configuration, and registration procedures are described here in the case of DCN (Digital CDMA (Code Division Multiple Access) Network System) and GSM (Global System for Mobile Communications).

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.58-59
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• 2012

본 논문에서는 벡터제어 인버터의 저가격화를 위해 고가의 홀전류센서 대신에 션트저항을 사용하면서 전동기의 모든 운전 영역에서 상전류를 정확하게 검출할 수 있는 새로운 2가지의 전류측정 방법을 제안한다. 첫째는 인버터의 3상 브리지 회로에서 상위 스위치와 직류링크의 양극(DCP : DC-link Positive) 단자 사이에 션트저항을 삽입하고, 하위 스위치와 직류링크의 음극(DCN : DC-link Negative) 단자 사이에도 션트저항을 삽입하여 상전류를 측정하는 방법이다. 둘째는 인버터의 출력단에 홀전류센서 대신에 션트저항을 삽입하여 상전류를 측정하는 방법이다. 이 2가지 전류측정 방법의 유효성을 컴퓨터 시뮬레이션과 실험을 통하여 검증한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.11
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• pp.2810-2816
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• 1996

In this paper, the problem of obtaining topoloty for mesh network given the link costs and traffic requirements between all pairs of nodes is considered. The proposed DCN algorithm can be applied to the mesh network in a unified manner. Among the cost conditions, the triangle intequality of the MENTOR algorithm is removed in the proposed algorithm. The computational complexity of the algorithm is order N$^{3}$, where N is the number of nodes in the network. The performances of proposed algorithm are better than those of the MENTOR algorithm in the case of the cost and the reliability of network.