• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.17-19
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• 1994

고분자 분리막의 구조가 투과율에 미치는 영향에 대해서는 지금까지 많은 연구가 행하여져 왔지만, 분자구조가 투과경로에 미치는 영향에 대한 연구는 아직 미미하며, black box approach만으로는 투과경로를 기술하기 어렵다. Impedance spectrowcopy는 막에 alternating electric field를 가해줌으로써 얻어지는 전류와 전압의 상관관계를 이용하여, 막내의 전해질의 투과에 대한 정보를 얻어내는 기기로써, dielectric loss spectra를 분석하면 투과물의 투과경로에 대한 정보도 얻을 수 있다. 전해질을 포함한 막의 dielectric loss ($\varepsilon"$) spectra는 다음의 식과 같이 두 부분으로 나뉘어 진다. $\varepsilon" = \varepsilon_{ac}" + \varepsilon_{dc}"$ (1) $\varepsilon_{dc}"$는 막을 통한 이온의 투과에 관계된 항이며, $\varepsilon_{ac}"$는 강한 dipole의 relaxation에 의해 나타나는 항이다. $\varepsilon_{dc}"$는 다음의 실험식에 의해 잘 기술되어진다. $\varepsilon_{dc}" = A\omega^{-n}$ 0

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04a
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• pp.121-124
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• 2002

문서의 고정된 스키마 없이 사용될 수 있는 XML문서를 관계형 데이터베이스에 문서 자체의 구조 정보와 함께 효율적으로 저장하려는 연구가 계속되고 있다. 계층적인 형태의 XML 문서들을 구조 검색하기 위한 정규 경로식 질의들을 평면 구조의 관계형 데이터베이스에서 처리하기 위해서 많은 비용이 필요하게 된다. 따라서 본 논문에서는 다양한 정규 경로식 질의들을 질의의 특성에 알맞은 방법으로 처리하는 저장 모델과 질의 처리 모델을 제안한다. 제안된 모델은 정규 경로식 질의에 포함된 경로 연산자를 분석하여 부모-자식 관계가 아닌 조상-자손 관계 조사에는 $\theta$-조인을 이용하고, 부모-자식 관계 조사에는 동등(equi)-조인을 이용하는 SQL문으로 변환 처리하여 질의 처리 효율성을 높였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10A
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• pp.775-779
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• 2003

A spatio-temporal searcher structure for 3rd generation W-CDMA systems is proposed to enhance the detection capability of the multi-path searcher for the desired signal. This searcher employs the spatio-temporal signal structure to search for newly emerging multipath signals. The proposed multi-path searcher provides better detection capability andthus reduces the mean acquisition time. The detection and false alarm probabilities of new and conventional schemes are calculated and numerical examples of mean acquisition time are given thereafter.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.2
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• pp.72-83
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• 2003

The main purpose of this study was to analyze the causal relationship, in the perspective of Total Quality Management, among the education quality factors, which were suggested in the previous researches, including education leadership, process improvement, educational environment, regional commitment, student performance and satisfaction of education quality. In this study, education quality factors were measured by several measures, and were processed with the most efficient statistical package in the SEM area, AMOS. In order to analyze the causal relationship among the education quality, this study designed the structural equation model with suggested factors and established several the research hypotheses. Also this study found that there was a prominent causality among the education quality factors, such as education leadership, education environment, student performance and satisfaction of education quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.71-80
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• 2021

The purpose of this study is to explore the structural relationships among parents' educational involvement and parental efficacy on students' school life satisfaction and school achievement and to determine whether there are any differences depending on family type and school level. Using data from 2,497 families that participated in the 2018 National Survey on Children's Life, t-tests and structural equation modeling were conducted. The results of this study demonstrated that two-parent families reported higher levels of educational involvement than single-parent families and custodial grandparent families. Also, two-parent families raising children in elementary schools showed higher educational involvement than two-parent families raising children attending middle schools. Second, parental efficacy was found to mediate the effects of parents' educational involvement on students' school life satisfaction and school achievement. Third, the path coefficients between parents' educational involvement, students' school life satisfaction, and school achievement showed statistically significant differences depending on family type, with two-parent families having greater involvement than single-parent families and custodial grandparent families. Fourth, multiple group analysis reported a statistically significant difference in the relationship between parents' educational involvement and school achievement as well as parental efficacy and school achievement depending on the school level.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.2
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• pp.4-10
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• 1993

In mobile radio communication, propagation paths are time or spacial varying because of the motion of mobile unit. The propagation path loss not only involves frequency and distance but also the antenna height at both the base station and the mobile unit, terrain configuration, and the man made en- vironment. Thhese additional factors make the prediction of propagation path loss of mobile radio signals more difficult. In this paper, it is measured field strenght of mobile radio signals in Daejeon and Seoul area, also calculated local median, 500m sample mean, and stadard deviation. As the result of analysis, it can be seen that propagation path loss of measured data is similiar to predicted field strength, especially local median is dependent upon base antenna height, terrain configuration and the man-made environment. The standard deviation has been noted to lie between 2 and 10 dBuV.

• Journal of KIISE:Databases
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• v.31 no.5
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• pp.553-566
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• 2004

Some of the current main research areas involving techniques related to XML consist of storing XML documents, optimizing the query, and indexing. As such we may focus on the set of documents that are composed of various structures, but that are not shared with common structure such as the same DTD or XML Schema. In the case, it is essential to analyze structural similarities and differences among many documents. For example, when the documents from the Web or EDMS (Electronic Document Management System) are required to be merged or classified, it is very important to find the common structure for the process of handling documents. In this paper, we transformed sequential pattern mining algorithms(1) to extract maximal similar paths between two XML documents. Experiments with XML documents show that our transformed sequential pattern mining algorithms can exactly find common structures and maximal similar paths between them. For analyzing experimental results, similarity metrics based on maximal similar paths can exactly classify the types of XML documents.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.382-385
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• 2003

Ad hoc 네트워크는 고정된 기반구조 없이 이동 노드들로만 구성된 네트워크를 가리킨다. 노드들의 이동으로 인해 네트워크 토폴로지는 예측할 수 없게 자주 변할 수 있다. 그 결과로 기 설정되어 있는 경로의 단절이 발생할 수 있으며, 새로운 경로가 설정될 때까지 데이터가 손실될 수 있다. 존재하는 경로의 단절로 인해 손실되는 패킷의 수를 줄이기 위해, 본 논문은 multiple-reply Ad hoc On-demand Distance Vector (mrAODV) 방식을 제안한다. 본 논문의 알고리즘은 발신지와 수신지 사이에 다중 경로를 설정한다. ns-2 시뮬레이션을 사용하여 제안된 방식에 대한 성능을 평가한다.

• The KIPS Transactions:PartC
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• v.10C no.5
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• pp.603-610
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• 2003

On the optical network, it is important to build restoration scheme capable to network survivability in preparation of potential failure on communication route. This paper analyze the existing schemes on restoration of failure on the optical network, and propose deferred commit scheme to improve resource utilization and management efficiency. Also, the transfer flow of messages needed for transferring restoration signal are presented in a concrete way and delay time required by shared mesh restoration scheme is explained in a substantial way. Simulation-based comparative analysis of various schemes is performed.

• Journal of the Korean Regional Science Association
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• v.34 no.4
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• pp.61-74
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• 2018

This study aims to analyze the convergence change of smart city industries in Korea. Industries of Smart city can be defined ICTs and Knowledge embedded construction industry. The input output model and structural path analysis have been done using the input output tables published by Bank of Korea in 1980 and 2014. GDP deflator was applied to the input output tables. 403 industries were reclassified into 27 industries and 8 industries categories: Agriculture and Mining(AM), Non-IT Manufacture(NITM), IT Manufacture(ITM), Energy Supply(EnS), Construction as smart city(C), IT Service(ITS), Knowledge Service(KS), Etc. Service(EtS). The results are as follows; First, the input output coefficient analysis showed that The information and communication service industry(ITS) and the energy supply industry(EnS) have increased input to the construction industry(C). On the other hands, knowledge service industry(KS) and etc. service industries(EtS) decreased. Second, the multiplier analysis revealed that construction industry(C) led by smart city had a great influence on ITS, EnS, ITM and NITM directly and indirectly. Furthermore, The IT industry had the biggest change from 1980 to 2014. Third, the smart city industry has created a new convergence of 117, and it has been leading to segmentation of the structure. Change of convergence has been proceeding mainly in the ITS and EnS, NITM, ITM industries.