• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.11
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• pp.44-52
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• 1998

In this paper, we proposed a node architecture and cell routing strategies for ATM applications in WDM multihop networks. The proposed node architecture employs the optical delay loop for storing the cell which is failed in out-link contention. This optical delay loop allows the delay of one cell without the electro-optic conversion. Therefore, we can get the advantages of S&F(Store-and-Forward) routing in Deflection-based all-optical networks. To support the ATM applications efficiently. we considered the transmission priority of ATM cell so that high priority cell can be transmitted with lower loss and shorter delay than low priority one. Two kinds of routing strategies are designed for this architecture: Scheme-Ⅰand Scheme-Ⅱ. Scheme-Ⅰapplies S&F routing to high cell and Deflection routing to low cell, i.e., high cells are routed along the shortest path based on S&F routing, but low cells are deflected or lost. Schem-Ⅱ is similar to Scheme-Ⅰexcept that low cells can occupy the optical loop if it is available. This Scheme-Ⅱ increases the utilization of network resources without decreasing the throughput of high cell by reducing the low cell loss rate when traffic load is low. Simulation results show that our routing strategies have better performance than conventional ones under non-uniform traffic as well as uniform traffic.

• Electronics and Telecommunications Trends
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• v.25 no.1
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• pp.132-147
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• 2010

IT 인프라를 통해 변화하는 비즈니스 우선순위에 따라 재사용 또는 결합 가능한 컴포넌트로 통합하는 표준화된 프레임워크인 서비스 지향 아키텍처를 구현하기 위한 핵심기술이 가상화이다. 이 가상화 기술 가운데 네트워크 가상화가 미래인터넷에서 중요한 기술적 이슈로 부상하고 있지만, 아직은 초기 단계이기 때문에 네트워크 가상화의 개념과 세부 기술 등이 모호한 상태이다. 이에 따라, 본 고에서는 미래인터넷 관점에서 네트워크 가상화에 대해 기술 동향을 파악하고, 전반적인 개념과 세부 기술을 다루어 보고자 한다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.381-386
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• 2001

RBI(Risk-Based Inspection)는 각각의 설비별로 위험등급 또는 위험도를 산정하고 이에 따라 검사의 우선 순위, 방법, 주기 및 일정계획 등을 수립하여 기술적인 근거에 의해 종합적이고 체계적인 검사를 수행하는 것이다. 이와 같이 RBI는 위험도를 정성적/정량적으로 평가하여 위험의 대부분을 내포하고 있는 30％ 내외의 소수의 설비를 찾아내어 이에 대해 최적의 방법으로 인적, 물적 자원을 집중적으로 투입함으로써 안전성 확보와 함께 경제성을 추구하는 효율적인 기법이라 할 수 있다.(중략)

• Proceedings of the Korea Society for Simulation Conference
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• 2000.11a
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• pp.198-203
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• 2000

NRCL(NaRae Hardware Control Language)은 C++ 기반의 산업용 객체 지향 실시간 언어이다. NRCL은 멀티태스킹이 가능하며, 이벤트 위주(Event-Driven) 방식의 가벼운 언어이다. 언어를 가볍게 만들기 위해 NRCL은 태스크를 최소 단위의 객체(컴포넌트)로 정의하였으며, 스케줄러(메시지 처리기)를 통해 우선 순위 방식으로 태스크들을 활성화시킨다. 본 논문에서는 효율적인 실시간 시뮬레이터 작성을 위한 객체지향 실시간 언어 NRCL을 제안하고, NRCL을 통한 재사용성, 이식성, 확장성, 유지 보수성을 보인다.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.173-176
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• 2003

본 논문은 컴포넌트의 재사용을 위한 퍼지 기반 컴포넌트 검색 인터페이스를 구현하였다. 컴포넌트 검색을 위해서는 클래스의 상속관계를 이용한 시소러스로 구축하였고, 이를 통하여 질의를 이용한 컴포넌트 검색이 가능하도록 하였다. 또한 검색결과는 우선순위로 보여줌으로서 질의에 대한 보다 빠른 검색이 되도록 하였다. 검색된 컴포넌트는 원시코드, 컴포넌트 정보, 클래스 다이어그램 둥을 제공함으로서 효율적인 컴포넌트 재사용이 가능하도록 하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.4
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• pp.394-401
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• 2013

Recently there have been much interest in the performance improvement of maritime communication system. In the maritime communication system, the wireless channel is likely to be time-invariant and the retransmission scheme is not proper because it does not provide time diversity. For the improvement of reliability, we consider MIMO ARQ scheme using Alamouti-type signal which can provide space and time diversity. In this paper, we also propose the criterion of optimal retransmission order and provide its performance of error probability and packet throughput. The proposed MIMO ARQ scheme with optimal retransmission order has performance gain over random ordered MIMO ARQ and conventional Chase combining method. Therefore we expect that it can be adapted to the next generation maritime communication system.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.368-371
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• 2003

This paper constructed component retrieval system for reusability of component. Constructed by thesaurus that use inheritance relation of class for component retrieval, and did so that component retrieval that use Queries may be available. Also, the retrieval result did to become faster retrieval about queries as that show by priority. Retrieved components made efficient component reusability to be possible as that support source code, component information, class diagram etc.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.493-499
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• 2014

This study aims to verify the effects of the life redesign educational program based on the baby boomer (11 members of experimental group, 12 members of control group). The program was conducted for two hours two times in a week in the area of Chungnam (Total 8weeks 16sessions). First, in the result of the Wilcoxon's pairs signed-ranks test between the pre-post tests for the analysis on the program effectiveness of the experimental group of baby boomer, the baby boomer of experimental group showed an improved perception of preparing the volunteer work in the perception of preparing their old age, and there was no pre-post significant differences in the control group. In case of the experimental group, perception of the post-retirement preparation, such as a physical preparation, emotional preparation, financial preparation, volunteer work preparation and leisure activities preparation increased in average. Second, the satisfaction for the program's educational process, educational contents, educational data, educational method, instructor and the educational environment were shown to be more than 3.5 points out of 5 points in full.

• Journal of KIISE
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• v.43 no.8
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• pp.927-932
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• 2016

With the explosive increase in the number of online medical documents, the demand for question-answering systems is increasing. Recently, question-answering models based on machine learning have shown high performances in various domains. However, many question-answering models within the medical domain are still based on information retrieval techniques because of sparseness of training data. Based on various information retrieval techniques, we propose an answer snippet retrieval model for question-answering systems of medical documents. The proposed model first searches candidate answer sentences from medical documents using a cluster-based retrieval technique. Then, it generates reliable answer snippets using a re-ranking model of the candidate answer sentences based on various sentence retrieval techniques. In the experiments with BioASQ 4b, the proposed model showed better performances (MAP of 0.0604) than the previous models.

• Journal of KIISE:Software and Applications
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• v.36 no.3
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• pp.236-243
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• 2009

With advances in topic detection and tracking(TDT), automatic trend analysis from a collection of time-stamped documents, like patents, news papers, and blog pages, is a challenging research problem. Past research in this area has mainly focused on showing a trend line over time of a given concept by measuring the strength of trend-associated term frequency information. for detection of emerging trends, either a simple criterion such as frequency change was used, or an overall comparison was made against a training data. We note that in order to show most salient trends detected among many possibilities, it is critical to devise a ranking function. To this end, we define four properties(change, persistency, stability and volume) of trend lines drawn from frequency information, to quantify various aspects of trends, and propose a method by which trend lines can be ranked. The properties are examined individually and in combination in a series of experiments for their validity using the ranking algorithm. The results show that a judicious combination of the four properties is a better indicator for salient trends than any single criterion used in the past for ranking or detecting emerging trends.