• Journal of Information Science Theory and Practice
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• 제3권4호
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• pp.19-34
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• 2015

Evaluation of retrieval systems is mostly limited to laboratory settings and rarely considers changes of performance over time. This article presents an evaluation of retrieval systems for internal Web site search systems between the years 2006 and 2011. A holistic evaluation methodology for real Web sites was developed which includes tests for functionality, search quality, and user interaction. Among other sites, one set of 20 Web site search systems was evaluated three times in different years and no substantial improvement could be shown. It is surprising that the communication between site and user still leads to very poor results in many cases. Overall, the quality of these search systems could be improved, and several areas for improvement are apparent from our evaluation. For a comparison, Google’s site search function was also tested with the same tasks.

• Asia pacific journal of information systems
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• 제1권1호
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• pp.87-101
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• 1991

The primary purpose of this study was to investigate a robust search methodology that could be used in full-text information retrieval systems. A robust search methodology is one that can be easily used by a variety of users (particularly naive users) and it will give them comparable search performance regardless of their different expertise or interests In order to develop a possibly robust search methodology, a fully functional prototype of a fuzzy knowledge based information retrieval system was developed. Also, an experiment that used this prototype information retreival system was designed to investigate the performance of that search methodology over a small exploratory sample of user queries To probe the relatonships between the possibly robust search performance and the query organization using fuzzy inference logic, the search performance of a shallow query structure was analyzes. Consequently the following several noteworthy findings were obtained: 1) the hierachical(tree type) query structure might be a better query organization than the linear type query structure 2) comparing with the complex tree query structure, the simple tree query structure that has at most three levels of query might provide better search performance 3) the fuzzy search methodology that employs a proper levels of cut-off value might provide more efficient search performance than the boolean search methodology. Even though findings could not be statistically verified because the experiments were done using a single replication, it is worth noting however, that the research findings provided valuable information for developing a possibly robust search methodology in full-text information retrieval.

• 한국정보관리학회:학술대회논문집
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• 한국정보관리학회 1997년도 제4회 학술대회 논문집
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• pp.37-53
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• 1997

The huge size of Internet does not allow ordinary information seekers to search information with ease. Now, it is almost impossible to navigate the ocean of information without effective search tools. Web search engine has been the most effective technology for information retrieval on WWW. But recently, the need for new search tools on WWW or Internet has increased drastically. Currently, there are many on-going researches on the related topics. In this survey, we categorize the new search tools into four types: monitoring systems, filtering systems, browsing assistant systems, recommending systems. These example systems are examined. We are especially interested in WWW information filtering. It is studied how to apply the information filtering techniques to WWW, The application is not so straightforward like Email, Newswire filtering systems. As a result of this study, a simple WWW information filtering system is proposed.

• 조명전기설비학회논문지
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• 제17권5호
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• pp.80-87
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• 2003

본 논문은 경험적인 탐색방법인 Reactive Tabu Search를 배전계통의 최적 재구성에 적용하였다. 일반적으로 Tabu search는 기울기가 감소하는 방향으로 탐색을 하기 때문에 적은 계산 시간으로 좋은 해를 얻을 수 있지만 초기의 계통 구성에 따라 수렴의 특성이 좌우되어 전역적인 최소해를 찾기가 어려운 단점이 있다 반면 RTS(Reactive Tabu search)는 reaction과 escape 메커니즘을 제공함으로써 파라미터 선정을 자동적으로 적응시키는 것이 가능하여 계통의 초기 구성에 관계 없이 전역적인 해를 적은 계산량으로도 찾을 수 있다. 렬 연구에서는 RTS의 reaction과 escape메커니즘 구현을 위하여 해싱 함수를 이용하였고 또한 제시된 방식을 32모선에 적용, 기존의 참고문헌과 비교함으로써 그 유용성을 입증하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제38권2호
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• pp.225-232
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• 2014

The traditional RAP (Redundancy Allocation Problem) of complex systems has considered only the redundancy of subsystem with homogeneous components. In this paper we extend it as a RAP of complex systems with heterogeneous components which is more flexible than the case of homogeneous components. We model this problem as a nonlinear integer programming problem, find its optimal solution by tabu search, and suggest an example of the efficient reliability design with heterogeneous components. In order to improve the quality of the solution of the tabu search, we suggest a modified tabu search to employ an adaptive procedure (1-opt or 2-opt exchange) to generate the efficient neighborhood solutions. Computational results show that our modified procedure obtains better solutions as the size of problem increases from 30 to 50, even though it requires rather more computing time. With some adjustment of the parameters of the proposed method, it can be applied to the optimal reliability designs of complex systems of ships.

• 대한전기학회논문지
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• 제40권2호
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• pp.135-143
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• 1991

The setting problem of protective devices in power distribution systems is a combinatorial search problem involving a lot of trial & errors to search for a proper solution which has a great impact for the system reliability. This paper discusses the nature of the problem and proposes a scheme to prune the decision tree achieving the efficient search for a setting solution by applying heuristic rules which utilize pattern informations of backup and primary devices. Its effectiveness is demonstrated through many tests on real systems.

• 한국정보통신학회논문지
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• 제9권8호
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• pp.1649-1655
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• 2005

동위상(I) 파일럿 채널에 할당된 셀룰러 셀 CCSSC와 직교위상(Q) 파일럿 채널에 할당된 핫 스팟 셀 HSCSSC가 공존하는 광대역 OFCDM 시스템에 환경하에서 분리된 I/Q채널 CCSC를 이용한 탐색 알고리즘을 제안하였다. 제안된 알고리즘은 이동 기지국에서 무선 인터넷을 사용하고자 할 때 셀룰러 셀 CCSSC의 영향으로 감소하는 최상의 핫 스팟 셀 HSCSSC을 빠르게 추적하는데 적합하다. 시뮬레이션 결과 제안된 셀 추적 알고리즘이 기존의 셀 추적 알고리즘과 비교하여 훨씬 빠른 결과를 수행할 수 있음을 보였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제12권4호
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• pp.300-307
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• 2012

When the volume of data grows big, some simple tasks could become a significant concern. Nearest neighbor search is such a task which finds from a data set the k nearest data points to queries. Locality-sensitive hashing techniques have been developed for approximate but fast nearest neighbor search. This paper introduces the notion of locality-sensitive hashing and surveys the locality-sensitive hashing techniques. It categories them based on several criteria, presents their characteristics, and compares their performance.

• 한국콘텐츠학회논문지
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• 제21권2호
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• pp.301-314
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• 2021

청년실업은 인적자원의 낭비와 국가 경제력 약화 등을 야기하는 전세계적인 경제 이슈이다. 구직효능감을 통해 적극적인 구직활동과 구직성과를 예측할 수 있다. 이에 본 연구에서는 Neuman의 systems model을 근거로 청년실업자의 구직효능감에 영향을 미치는 요인을 확인하였다. 연구 결과, 청년구직자의 구직효능감에는 구직기간, 취업스트레스, 문제중심대처능력 등이 영향을 주고 있었으며, 특히 신체적으로 건강하다고 인지할수록 구직에 대한 효능감이 높게 나타났다. 따라서 청년구직자의 구직효능감을 증진하기 위해서는 청년들을 위한 사회적 제도 마련 뿐만 아니라, systems model에 기반하여 개인 체계 내에서의 정상방어선인 문제중심 대처능력을 최적화하고 저항선인 신체적 건강상태를 최상으로 유지할 수 있는 중재방안을 모색하는 것이 필요하리라 본다.

• 한국컴퓨터정보학회논문지
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• 제19권1호
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• pp.203-213
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• 2014

본 논문에서는 곤충 종의 외관구조인 머리, 몸통, 날개, 다리에 대한 관찰자의 일반적이고 수평적인 관찰특성에 따라 자유롭게 곤충 종을 관찰함으로써 관찰 곤충 검색엔진에서의 사용자 만족도 제고와 보다 효율적인 관찰학습의 방법을 제안한다. 자연생태 환경에서 초보 학습자의 효율적인 관찰검색과 효과적 학습을 위해서는 생물학적 분류체계가 아닌 곤충 종의 외관구조 즉, 외부 신체구조의 모양과 특성 중심의 곤충관찰 기반의 검색(Insect Search by Observation based on Insect Appearance: ISOIA)이 필요하다. 그러므로 본 연구에서는 곤충의 외관구조인 머리, 몸통, 날개, 다리에 대한 관찰자의 일반적인 관찰방법에 따른ISOIA 검색방식을 제안하고, 기존의 ISBC와 ISOBC 검색체계에 대한 사용 만족도를 비교 분석하여 본 논문에서 제안하는 ISOIA 검색 방안이 우수함을 보이고자 한다.