• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1031-1035
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• 2005

조력발전 건설사업에서 우선적으로 고려되어야 할 사항은 조수간만에 의해 외해부와 조지부 사이를 이동하는 해수를 적절히 소통시키는 것이다. 즉, 조력발전소에서 수문구조물의 목적은 주어진 조건 하에서 계획된 유량을 충분히 그리고 안전하게 배제시키는 것이다. 본 연구에서는 수문구조물에 대한 Apron의 길이와 경사의 변화에 의한 외해 조위와 시화호 수위차 조건에 따른 유량계수를 구해 배수능력과 유$\cdot$출입부, 외해, 시화호 및 큰가리섬 주위의 흐름 특성을 검토하고자 하였다. 이를 위해 시화호를 실험대상으로 하여 구조물을 중심으로 외해측으로 1,000m, 시화호측으로 500m, 폭 1,500m의 범위를 선정하였다. 수리모형을 1대50의 축척비로 제작하였다. 표 1은 실험별 Apron과 수문구조물의 제원을 나타내며, 수문구조물은 7기로 이루어졌다. 시화호의 흐름은 관성력과 중력이 지배력이 되며, 이때 상사법칙은 Froude 상사법칙을 적용할 수 있다. 실험III은 실험II에서 Apron의 경사를 1대10에서 1대5로 수정한 실험으로 수위조건은 외해측 -2.530 EL.m이고, 시화호측은 -1.603EL.m이다. 유량계수를 산정하기 위하여 6개 실험조건을 기본계획에서 제시된 수위-조위 조건에서 수위차 및 통수유량을 분배하여 결정하였고 유량계수 산정식에 따라 구조물의 유입부와 유출부에서 유속-면적법에 의해서 유량을 측정하였다. 그리고 국부평면 실험모형에서의 전체적인 해류의 흐름을 분석하기 위해 2차원 유속을 측정하였다. 또한, 유$\cdot$출입부 안정성을 검토하기 위해 Apron 지점과 수문구조물 지점에 3점법으로 유속을 측정하였으며, 색소를 이용하여 유황을 관찰하였다. 시화호와 외해의 수위차가 1.011 m일 때의 전체 수문구조물을 통과하는 유량을 비교한 결과, 실험II 및 실험III의 통과유량은 각각 $10,924m^3/s$ 및 $10,075m^3/s$로서 실험 I의 $2,757m^3/s$에 비해 통수능이 많이 개선되었음을 알 수 있다.

• Polymer(Korea)
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• v.38 no.3
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• pp.386-390
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• 2014

Efficient stitching methods for the synthesis of tripodal Fr$\acute{e}$chet-type dendrimers containing secondary amine as a connector were elaborated. The synthetic strategy involved Staudinger/aza-Wittig reactions (new click reaction) between tripodal tris(azides) and aldehyde-dendrons in toluene in the presence of triphenylphosphine and followed by the reduction of imine intermediates. The tripodal core (1,3,5-tris-(3-azido-propoxy)-benzene) was chosen to serve as the azide functionalities for dendrimer growth. 1,3,5-Tris-(3-azido-propoxy)-benzene was stitched with the aldehyde-functionalized Fr$\acute{e}$chet-type dendrons via Staudinger/aza-Wittig reactions leading to the formation of the corresponding Fr$\acute{e}$chet-type dendrimers in high yields.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.9
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• pp.956-963
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• 2002

A linearly polarized folded type and H-shape slit folded type microstrip patch antenna at GPS(center frequency:1.575 GHz) were designed and fabricated by folding a conventional single $\lambda_{g}/2(\lambda_{g}:wavelength)$ rectangular patch a half along the length direction at the center of patch and inserting ground plane in the middle. As a result, two types of omnidirectional radiation patterns for E-plane (for zx-plane) in the direction of the length of patch and H-plane (for xy-plane) have been acquired. The experimental results show that the average gains of folded type and slit folded type for omnidirectional E-plane and H-plane are -1.5 dBd (-2.4 dBd) and -3.27 dBd(-2.5 dBd). Slit folded type microstrip patch antenna was more miniaturized than folded type microstrip patch antenna by 27.5 %. In case of slit folded type antenna, average gains of omnidirectional radiation pattern for E & H-plane are almost same.

• Journal of Korea Multimedia Society
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• v.10 no.10
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• pp.1356-1366
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• 2007

Many personalized Services that provide users with adaptive information according to users' requirements and preferences have been researched and developed. However, existing approaches are difficult to share a user's information among heterogeneous services because these approaches manage users' preferences in a single system. In this paper, we propose a user preference sharing model based on the Semantic Web as a solution to resolve the problem. Our model enables user preferences to be described and shared over service-specific ontologies which are affected by the feature of each service. Our model is analyzed and evaluated with an implementation of the middleware that supports our model. Our approach has the advantage of providing more efficient personalized services than existing approaches because it can describe users' preferences centering around each service and share these information among heterogeneous personalized services.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2078-2086
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• 2011

The purpose of this study is to study internal and external factors affecting entrepreneurial intention of korean professional soldiers who are supposed to retire less than one year. Another main focus of this study is to find out whether there is mediating effect of entrepreneurial support programs for entrepreneurial intentions. In this research, data were collected from 361 officers and non-commission officers who are scheduled to retire from the military within 5 months to one year after at least 10 years of military service. The collected data were analyzed by SPSS using the regression analysis method. In this study, we found that internal factors did not positively affect entrepreneurial intentions, however, external factors positively affected entrepreneurial intentions. It was also found that entrepreneurial support programs played important role as moderating variables between social perceptions toward entrepreneurs and their entrepreneurial intentions. Based on these findings, implications of research implications are discussed, and recommendations for future research were provided.

• Communications of Mathematical Education
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• v.25 no.1
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• pp.1-19
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• 2011

HPM(History and Pedagogy of Mathematics) become an important issue to us now. Study on old Korean mathematics books were made recently. We study mathematics books in Kyujanggak in this article. Horng Wann-Sheng 洪萬生, an math. historian and a member of editorial board of Historia Mathematica, visited Kyujanggak, the royal library of Joseon Dynasty. After his visit, he published a paper, "The first visit to mathematics books in Kyujanggak 奎章閣收藏算書初訪"(2008 Kyujanggak 32, p. 283-293). In his paper, he also raised several research problems on the history of Korean mathematics. In this paper, we analyze his paper "The first visit to mathematics books in Kyujanggak" and give some answers to those raised problems on Korean mathematics. Also we correct some misunderstanding of Horng on some facts. Especially, we make it clear that the author of SinJungSanSul(New Arithmetics 新訂算術) was not Lee Sang-Seol(李相卨), whom Horng considered as the author, but Lee Gyo-Seung(李敎承) through the correct translation of its preface and an article about its copyright lawsuit. And we added some pathways how Chinese mathematics books were imported by Joseon. We introduce the case of Hong Dae-Yong(洪大容) in detail.

• Journal of Korea Multimedia Society
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• v.14 no.2
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• pp.318-328
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• 2011

This paper suggests a comprehensive method to describe architectural components for supporting Korean Traditional Building design with only small components set in CAD system. Korean traditional buildings can be classified variously based on the their size, usage and structure type(whether ornament part, namely Gongpo, is in there or not). Moreover components can be varied according to the combining rule between them. If all of these components are presented, these tremendous components rather prevent the efficient design of traditional buildings. In order to solve this problem we present object-oriented approach to describe versatile components as one template if they are same in functional aspects. From the template, many similar instances can be derived according to the attribute value. The templates are designed in order to reflect the coupling scheme between components in the relative parameters of the templates. It leads effects of minimizing error which can be occurred frequently in the process of traditional building design.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.11
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• pp.84-90
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• 2010

In this paper, the reduced size of broad bandpass filter with parallel coupled line structure is presented. This proposed filter can control bandwidth of narrow to broadband by adjusting the coupling coefficient. The conventional filter is operated with a narrow band. If a higher bandwidth is desired than the conventional narrow bandwidth, it is hard to realize due to the coupling coefficient between feeding line and resonator. In this paper, to overcome this limitation, a proposed bandpass filter is designed with reduced size due to SIR(Stepped Impedance Resonator) and multi-grade type structures than conventional one, and it has characteristics of adjusting bandwidth freely as per quantity of coupling coefficient. The proposed bandpass filter that, experimental results of insertion and return losses are 0.42 dB and 20.9 dB with bandwidth of 60 % at the center frequency of 5.8 GHz, respectively.

• Journal of Intelligence and Information Systems
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• v.13 no.3
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• pp.1-15
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• 2007

Recently, semantic web technology, represented by ontology building, is being combined with web services technology, creating 'Semantic Web Services' as a new promising field in information retrieval research. Accordingly, many brokering and matchmaking agents are being developed and used in the field. However, literature review revealed that most models do not take QoS(Quality of Services) into consideration. In this study, a QoS-augmented matchmaking algorithm is developed based on service availability, response time, maximum transaction amount, reliability, accessibility and price as critical QoS items. A prototype for Intelligent Semantic Web Services System is developed using publicly available data. Performance test was conducted and reported at the end.

• Journal of Global Scholars of Marketing Science
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• v.6
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• pp.185-210
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• 2000

범세계적 환경에서 시스템 전체가 대응하는 단일조직으로 국제기업의 기본 틀을 유지하면 서 해외자회사를 효율적으로 통제하는 것은 국제기업의 의사결정과점에서 고려되어야 할 중요한 과제이다. 또한 한국기업의 국제화가 성숙되고 있는 현시점에서 볼 때 진출초기단계의 의사결정문제에서 벗어나 실행된 투자에 대한 사후 관리적 측면에 대한 연구의 필요성이 증 가하고 있다. 이러한 관점에서 본 연구는 한국기업 해외자회사를 대상으로 모-자회사간의 의 사결정과정에서 발생되는 자원준거요인, 상황요인, 해외직접투자 요인에 의한 전략적 통제문제에 관해 실증 분석하였다. 연구의 분석결과, 모회사와 해외자회사 내부자원의 상호의존성이 높으면 높을수록 해외자 회사에 대한 모회사의 전략적 통제는 높을 것이라는 가설검정결과, 고통제집단의 경우, 재무 마케팅 기술 국제경영능력으로 측정된 내부능력에 있어 모두 높은 정의 상관관계가 있는 것으로 분석되었고, 저통제집단의 경우 국제경영능력을 제외한 3개 부분에서는 상관관 계를 보이지 않아, 연구가설의 이론적 예상을 부분적으로 반영하고 있다. 둘째, 해외자회사의 과업환경의 불확실성이 높을수록 해외자회사에 대한 모회사의 전략적 통제는 낮을 것이라는 가설검증결과, 환경의 불확실성이 높은 집단이 낮은 집단 보다 인사 마케팅 생산 재무 등의 4개 부문 모두에서 상대적으로 모기업의 통제가 낮게 나타났지만 생산부문은 통계적으로도 유의하지 않는 것으로 나타났다. 과업환경의 불확실성이 높을수록 모회사의 전략적 통제는 낮다는 이론적 예상을 부분적으로 반영하고 있다. 셋째, 해외자회사의 소유지분과 전략적 통제사이에는 유의 적인 상관관계가 존재할 것이라 는 가설의 검증결과는, 마케팅 분야에서만 완전소유 자회사가 다수소유 자회사보다 모회사의 통제의 정도가 상대적으로 높은 것으로 나타났지만 통계적으로 유의하지 않게 나타났다.