• Title/Summary/Keyword: the 2000s

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Photopolymerization of Methyl Methacrylate with 1,4-$C_6H_4(SiH_{3-x}Me_x)_2$

  • U, Hui Gwon;O, Eun Mi;Park, Jong Hak;Kim, Bo Hye;Kim, Yong Nam;Yun, Chan Ho;Ham, Hui Suk
    • Bulletin of the Korean Chemical Society
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    • v.21 no.3
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    • pp.291-294
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    • 2000
  • The bulk photopolymerization of methyl methacrylate(MMA) with bis(silane)s such as 1,4-$C_6H_4(SiH_3)_2$ (1) and 1,4-$C_6H_4(SiH_2Me)_2$ (2) was performed to produce poly(MMA)s possessing the corresponding bis(silyl) moiety as an end group. For the bis(silane)s, while the polymerizaiton yields and the polymer molecular weights decreased, the TGA residue yields and the relative intensities of Si-H IR stretching bands increased as the relative bis(silane) concentration over MMA increased. The polymerizaion yield, polymer molecular weight, and TGA residue yield of MMA with 1 were found to be higher than those with 2. The bis(silane)s appears to influence significantly upon the photopolymerization of MMA as both chain initiation and chain transfer agents.

The Study on the Historical Development of Japanese Social Security System in view of the Elderly - From the Concept-Formation Period for Social Secuiry of 1946 to the Implementation of Nursing Care Insurance of 2000 - (고령자 관점에서 본 일본 사회보장제도의 역사적 전개에 관한 연구 - 1945년 사회보장 개념성립부터 2000년 개호보험의 시행까지 -)

  • Lee, Jeong-Nam;Yoon, Cheol-Jae
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.16 no.3
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    • pp.7-18
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    • 2010
  • The purpose of this study is to derive periodical characteristics of the policy for the elderly in Japan by investigating the changes of social security system. The target period of 1946~2000 in Japan was divided into 3 periods for the understanding of periodical characteristics in the focuses of medical, welfare and pension system for the elderly; establishment of concept for the social security and welfare of Japan(1946,1950), appearance of social security system and the elderly problem(to late 1960's), infra construction for aging society(to late 1980's), development and reappraisal of practical policy for the elderly(to late 1990's). It is expected that this paper could provide basic data for the elderly-related policy making in our country.

Effects of the Musical Characteristic Change of 'Hip-hop' Culture on Popular Fashion (힙합문화의 음악적 특성 변화가 대중 패션에 미친 영향)

  • Park, Han-Him
    • The Research Journal of the Costume Culture
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    • v.19 no.2
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    • pp.416-429
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    • 2011
  • Most of precedent studies related to hip hop culture and fashion, which have been conducted till now were progressed under only theoretical background of hiphop, not the changed status of hiphop currently. Practical studies explaining the status of hip hop in popular culture, especially, the area of popular fashion are insufficient. Therefore, this study was conducted by focusing on cultural characteristics and musical characteristics by the stream of period, for which concept hip hop is accepted to people currently and which effect it makes on the area of fashion. Especially, the study was progressed by dividing periodical background into before and after the 2000s because there was the most noticeable change for the genre of hip hop in that period. Because of the appearance of 'Alternative hip hop' which is a sub-genre of hip hop music, hip hop music was changed to be more popular. Also, hip hop fashion also showed big changes. Hip hop fashion before 2000s had showed poor conditions, resistance, complex and alienation of them by their fashion. On the other hand, hip hop fashion after 2000s also showed popular characteristics because of high-level environment and social status. This study intended to understand and grasp hip hop as a kind of cultural situation coexisted by many-sided characteristics as well as redefine the changed concept and contents of new hip hop currently.

Exploring the Trend of Korean Creative Dance by Analyzing Research Topics : Application of Text Mining (연구주제 분석을 통한 한국창작무용 경향 탐색 : 텍스트 마이닝의 적용)

  • Yoo, Ji-Young;Kim, Woo-Kyung
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.6
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    • pp.53-60
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    • 2020
  • The study is based on the assumption that the trend of phenomena and trends in research are contextually consistent. Therefore the purpose of this study is to explore the trend of dance through the subject analysis of the Korean creative dance study by utilizing text mining. Thus, 1,291 words were analyzed in the 616 journal title, which were established on the paper search website. The collection, refining and analysis of the data were all R 3.6.0 SW. According to the study, keywords representing the times were frequently used before the 2000s, but Korean creative dance research types were also found in terms of education and physical training. Second, the frequency of keywords related to the dance troupe's performance was high after the 2000s, but it was confirmed that Choi Seung-hee was still in an important position in the study of Korean creative dance. Third, an analysis of the overall research subjects of the Korean creative dance study showed that the research on 'Art of Choi Seung-hee in the modern era' was the highest proportion. Fourth, the Hot Topics, which are rising as of 2000, appeared as 'the performance activities of the National Dance Company' and 'the choreography expression and utilization of traditional dance'. However, since the recent trend of the National Dance Company's performance is advocating 'modernization based on tradition', it has been confirmed that the trend of Korean creative dance since the 2000s has been focused on the use of traditional dance motifs. Fifth, the Cold Topic, which has been falling as of 2000, has been shown to be a study of 'dancing expressions by age'. It was judged that interest in research also decreased due to the tendency to mix various dance styles after the establishment of the genre of Korean creative dance.

Analysis and Optimization of Cross-Modulation Noise in CDMA Cellular RF System (CDMA 셀룰러 RF 시스템에서 교차변조 잡음 레벨 분석 및 최적화)

  • 곽준호;김학선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.6A
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    • pp.397-404
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    • 2003
  • In this paper, we have analyzed the level of cross-modulation noise required for CDMA mobile station and proposed a guideline for optimum design. From the analysis, the level of cross-modulation noise is determined by the system's noise figure(NF) and VCO's phase noise and there is a trade-off relationships between them. In addition, we have determined the value of LNA's IIP3 and duplexer's isolation to satisfy the above level in designing the system. Therefore, this paper will give a guideline for a selection of components in designing cdma2000 mobile station.

A Study of the Best Performance Index for Estimate at Completion Forecasting Model on the Earned Value Management System(EVMS) (EVMS 최종공사비 예측 모델 최적성과지수에 대한 고찰)

  • Kim Seon-Gyoo;Kim Jae-Jun
    • Korean Journal of Construction Engineering and Management
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    • v.1 no.3 s.3
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    • pp.101-107
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    • 2000
  • On 1 July, 2000, the Ministry of Construction and Transportation announced the Earned Value Management System(EVMS) will be applied in public sector soon. However the arguments over the EVMS applied to our unique construction environment still exist and create strong concerns and worries among some experts it would be another mistakes proposed by the government. We do know the EVMS comes from C/SCSC which was first released by the United States Department of Defense in December 1967, and proved very powerful and efficient project management tool from a lot of practices. Although it is an excellent tool, we can not ignore our many experienced failures appling foreign system due to the differences of construction culture and law between the Korean and US construction industries. The purpose of the EVMS's success in Korea, therefore, this paper tests and proves the EVMS's adaptability and credibility to our construction environment by EAC model, that is one of the most important functions in the EVMS, using very scare EV data of the Korean construction projects.

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Photocatal~ic Hydrogen Evolution with Platinum Loaded Cadmium-Iron-Sulfide Mixed Crystal Powders in Aque-ous Media

  • Jo, Cheol Rae;Park, Se Jin;Kim, Ha Seok
    • Bulletin of the Korean Chemical Society
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    • v.21 no.8
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    • pp.805-808
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    • 2000
  • Mixed crystal powders based on Cd,Fe, and S have been synthesized by varying the ratio of CdS and $FeS_2in$ order to find a suitable material usefuI for the effectivc conversion of solar energy. Hydrogen gas was evolved only with CdS/Ptby photocatal ytic reaction under white light in an aqueous 1 M sodiumsulfite solution. From electrochemical studies of semiconductor electrodes. itwas shown that the onset potential shifted to the positive direction and that the bandgap energy also decreased as the molar ratio of Fe increased. A hydrogen evolution mechanism in terms of the conduction band potential and hydrogen evolution potential is proposed.

Design & Implementation of Information Retrieval & Management System KRISTAL-2000 (정보검색관리시스템 KRISTAL-2000 설계 및 구현)

  • 이민호;진두석;김광영;주원균;서정현;류범종
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04a
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    • pp.653-655
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    • 2003
  • 데이터베이스를 구축하고 서비스하기 위한 대부분의 방식은 상용 DBMS를 사용하여 문서에 대한 관리를 수행하고, 사용자 검색을 수행하기 위해 정보검색 시스템을 사용하는 DBMS와 정보검색 시스템의 연동방식을 채택하고 있다. 이러한 환경은 DBMS와 정보검색 시스템을 이중으로 운영하여야 하는 불편함이 있고, 변동된 문서에 대한 데이터 일관성을 유지하기 어렵고, 데이터를 중복 저장하므로 저장 공간의 낭비를 가져온다. DBMS를 기반으로 정보 검색 시스템을 밀결합하는 방법도 있으나 검색 속도저하문제를 야기하였다. 본 논문에서는 정보 검색 시스템을 바탕으로, DBMS의 필수 요소인 안정적인 문서 관리 부분을 접목한 정보검색 관리 시스템을 설계한다.

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