• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.66-68
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• 2011

정지궤도위성인 천리안위성의 이원추진시스템은 크게 궤도전이를 위한 1기의 주엔진과 궤도상 운용에 주로 사용되는 14기의 추력기들로 구성된다. 천리안위성은 프렌치 기아나의 쿠루우주센터에서 성공적으로 발사되었다. 발사체에서 분리 후 추진시스템은 자동으로 초기화되었다. 이후 3번의 주엔진 분사가 성공적으로 수행되었으며 목표궤도 진입에 성공했다. 본 논문에서는 천리안위성의 발사 및 발사후 초기운용 과정에서의 주요 정황들에 대해 상술한다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.207-210
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• 2011

천리안 이원추진시스템은 궤도전이를 위한 1기의 주엔진과 궤도상 운용에 주로 사용되는 14기의 추력기들로 구성된다. 추진계의 설계 및 해석은 국제협력을 통해 수행되었다. 시스템 조립 및 시험 후, 천리안위성은 프렌치 기아나의 쿠루우주센터로 이송되었으며, 성공적으로 발사되었다. 발사체에서 분리 후 추진시스템은 자동으로 초기화되었다. 이후 3번의 주엔진 분사가 성공적으로 수행되었으며 목표궤도 진입에 성공했다.

• 대한원격탐사학회지
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• 제27권6호
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• pp.753-760
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• 2011

The satellite Chollian was successfully launched on June 27, 2010 and is expected to perform its communication, oceanographic, and meteorological duties for seven years. The follow-up launch of the Chollian satellite is already being planned, and diverse studies are under way to enable the use of the Korean satellite data. Studies are also being actively conducted in and out of Korea to visualize the meteorological data on the open-source virtual globes. The meteorological data include ground observation, satellite, and digital-model data. In this study, an efficient three-dimensional technique was developed to visualize typhoons on the virtual globes using the Chollian satellite data. This study was conducted to provide service to the public via the scientific visualization of the satellite image data, and to create an efficient satellite image analysis environment for meteorological researchers.

• 한국항공운항학회지
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• 제19권1호
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• pp.94-100
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• 2011

This paper gives a brief overview of the COMS CPS development process from start to finish. The manufacturing techniques used for CPS were founded on established generic processes that have been developed and proven on previous satellite programs, and have used the expertise and facilities in the framework of international collaboration. Manufacture and testing of the CPS were successfully accomplished, and COMS CPS demonstrated good performance in the launch phase.

• 한국문헌정보학회지
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• 제24권
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• pp.171-204
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• 1993

The purpose of this study is to verify the hypothesis that the contents and range of library services are changed as the use of videotex systems increases. 1000 members of Chollian II were chosen as subjects for this study and the questionnaire was posted to them. The returned responses to questionnaire were analyzed with the statistical software packages 'SAS PC' and 'STATGRAPHICS'. The findings and conclusions of this study are summarised as follows: 1. Users of Chollian II make more use of videotex systems in seeking daily information than in seeking scholarly and professional information. It seems desirable to co-ordinate the services of videotex systems and libraries by redefining the traditional boundary of the two systems. Users will then conveniently get daily information through videotex servics, scholarly and professional information through the reference service of libraries. 2. Sex does not make any significant difference in the use of videotex systems. Most frequent use of videotex systems is made by those at the age of thirties. Businessmen and enterprisers make the most frequent use of videotex systems. Those of higher education are the best users. 3. As the use of videotex systems increases, use of newspapers and periodicals decreases while its increase rarely has influence on the use of library materials. 4. There is limited correlation between the use of videotex systems and that of library services. The increase of the use of videotex systems does not significantly increase or decrease the use of libraries. It changes, however, the pattern and methods of information services provided by libraries. 5. Users of special libraries make the most frequent use of videotex systems and there is not much difference in the use by users of other kinds of libraries.

• 한국태양에너지학회 논문집
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• 제39권3호
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• pp.47-57
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• 2019

Clear sky indices were estimated by various ways based on in-situ observation and satellite-derived solar irradiance. In principle, clear sky index defined by clear sky solar irradiance indicates the impacts of cloud on the incoming solar irradiance. However, clear sky index widely used in energy sciences is formulated by extraterrestrial irradiance, which implies the extinction of solar irradiance due to mainly aerosol, water vapor and clouds drops. This study examined the relative difference of clear sky indices and then major characteristics of clear sky irradiance when sky is clear are investigated. Clear sky is defined when clear sky index based on clear sky irradiance is higher than 0.9. In contrast, clear sky index defined by extraterrestrial irradiance is distributed between 0.4 and 0.8. When aerosol optical depth and air mass coefficient are relative larger, solar irradiance is lower due to enhanced extinction, which leads to the lower value of clear sky index defined by extraterrestrial irradiance.

• The Plant Pathology Journal
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• 제15권6호
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• pp.340-344
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• 1999

Fungicide-resistant isolates of Monilinia fructicola grew readily on media amended with 0.1, 1.0, 10, 100 and $1,000\mu\textrm{g}$ a.i./ml of carendazim, benomyl, or thiophanate-methyl. However, sensitive isolates did not grow on media amended even with $0.1\mu\textrm{g}$ a.i./ml of carbendazim, $1.0\mu\textrm{g}$ a.i./ml of benomyl or thiophanate-methyl. The fitness compositions including mycelial growth on fungicide-free medium, sporulation on fungicide-free medium and pear, and virulence on pear were not different between resistant and sensitive isolates. The resistant isolates persisted carbendazim resistance during multiple subdulturing and long term storage. The competitive ability of resistant isolates obtained from peach orchards in Korea was similar to those of sensitive isolates.

• 시큐리티연구
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• 제6호
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• pp.195-213
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• 2003

This is a case study on the violent collective activities of spectators in professional soccer games. The purpose of this study is to examine the reasons and the processes of the activities. In order to achieve the purpose well, I analyzed two cases of violent collective activities in spectators of professional soccer games that were held on June 24 and July 28 in 2001. The data for this study was collected from 14 kinds of daily newspapers from June 10 to August 20 in 2001 to maintain the objective validity of the outline, the reasons, and the processes of the violent collective activities of spectators in two cases. The data was collected from Korea Integrated News Database System(KINDS) of Korea Press Foundation, and Chollian, on-line service of DACOM, for its efficiency, accuracy and promptness. On the basis of the above-mentioned method as well as the consequences of data analysis, I've reached to a conclusion as follows. The reasons of the violent collective activities of spectators in professional soccer games were the mass effect, the activities of players, umpires and the results of games, etc. The violent collective activities of spectators in professional soccer games need pre-requirements and have relationships with special affairs that are developed in a regular sequence. In other words, a collective activity gives an effect on another one directly or indirectly. Therefore, this study shows that we can reduce or prevent the damages by the violent collective activities of spectators in sport games when we analyze the processes of collective activities and make a previous counter-measure for that.

• 정보기술응용연구
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• 제3권4호
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• pp.93-117
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• 2001

기업 뿐 아니라 사회의 개별 구성원에게 있어서도 컴퓨터 통신 기술의 활용이 급속히 확산됨에 따라 이러한 가상 공간상에서의 활동에 대한 관심이 높아지고 있다. 특히, 가상사회에서의 상거래를 다루는 전자상거래에 대한 연구는 기업과 기업간 전자상거래에 대한 연구를 넘어 기업과 고객간의 전자상거래에 대한 연구로 확대되고 있다 그러나 전자상거래를 이용하는 소비자에 대한 연구와 이해는 아직도 여러 가치 측면에서 매우 미흡한 실정에 있다. 실물 공간에서의 소비자에 대한 마케팅 분야에서의 연구가 새로운 거래 패러다임인 전자상거래에 대한 설명으로 확대될 수 있는 범위와 논리도 아직 충분하지 않으며, 소비자이며 동시에 기술 사용자라는 특성이 어떻게 통합될 수 있는지에 대한 연구도 미흡한 실정이다. 전자상거래를 추진하고 있는 사업자에게 있어서는 가상사회의 이용자에 대한 심도 있는 분석과 이해가 필수적인 요건이 될 것이다. 본 연구에서는 가상사회에서의 기술 이용자의 개인적인 심리적 특성이 매체와 기술의 이용패턴과 어떤 관련성을 가지고 있는지를 분석함으로써 가상사회 구성원의 행태적 특성을 파악해 보고자 하였다.

• 한국지구과학회지
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• 제39권2호
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• pp.131-138
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• 2018

본 연구의 목적은 위성의 밝기온도를 기반으로 한 정량적 강우량 추정기법의 개선을 위함이다. 우리나라 여름철 강우사례를 이용하여 강우추정을 위한 비선형 관계식을 개선하였다. 분석을 위해 레이더 자료로 기상청 기상레이더 관측망의 고도 1.5 km와 CMAX 반사도 합성자료를 사용하였으며, 위성자료는 천리안 위성의 가시, 적외, 수증기 채널의 자료를 이용하였다. 새롭게 도출된 알고리즘은 A-E method, CRR v4.0 analytic function의 결과와 비교를 하였다. 검증을 위해 우리나라 ASOS에서 관측한 지상강우량 자료를 사용하였다. 공간검증을 위해 검증지수로 POD, FAR, CSI를 계산하였으며 각각 0.67, 0.76, 0.21로 나타났다. 정량적 강우검증을 위해 MAE와 RMSE를 계산하였으며 각각 2.49, 6.18 mm/h였다. A-E에 비하여 정량적인 오차가 줄어들었으며 CRR에 비하여 공간적인 정확도가 증가하였다. 개선한 관계식을 적용한 방법이 두 알고리즘의 부족한 부분을 보완할 수 있는 것으로 판단된다. 개선한 관계식을 통해 강우를 추정하는 방법은 복잡한 알고리즘을 거치지 않고 짧은 시간에 강우추정이 가능함으로써 현업용 실시간 초단기 예보에 활용될 수 있다.