• 한국항공우주학회지
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• 제38권11호
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• pp.1144-1151
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• 2010

지난 50여년의 우주개발로 인해 현재 지구궤도 상에는 수많은 우주파편이 인공위성이나 우주선을 위협하고 있다. 현재 아리랑 위성 2호와 5호의 임무궤도가 포함된 LEO에 전체 우주파편의 84%가 존재함에 따라 우주파편을 고려한 우주임무설계가 요구된다. 본 논문에서는 ESA의 MASTER2005와 NASA의 DAS2.0을 이용하여 현재 활동 중인 아리랑 위성 2호와 발사예정인 아리랑 위성 5호의 임무궤도에 존재하는 우주파편의 종류, 궤도특성, 우주파편이 차지하는 공간밀도를 비교분석하였고, 임무 중에 우주파편과 충돌하거나 손상을 입을 확률을 계산하였다. 분석 결과 아리랑 위성 2호의 우주파편 충돌확률이 아리랑 위성 5호에 비해 약 5배정도 높은 것으로 나타났다.

• 한국주거학회논문집
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• 제16권4호
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• pp.91-100
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• 2005

This study aims to find the architectural concepts of Song-Sun and the spatial structure of the Myonangjong through kasa, sijo, and Chinese poems. He considered his place as a ideal place to dwell a secluded life which is surrounded by mountains, and opened to a field in front. That places is connected with geomancy or Feng Sui, and he attached great importance to placeness of the Myonangjong as a pavilion. As his place was called 'tyoro samgan', his place should be simple, and that was harmonized with nature. He regarded his place as a part of the outside space and its surrounding nature. As the pen name of Myonangjong shows that his way of life is very pure so he need not disgrace against the earth and the sky, he considered his building as a place of embodying the Confucian great law of heaven and earth. Myonangjong has a concentric circle structure of the scenery which is viewed panoramically along with the visual direction.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.71-74
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• 2006

Communication Ocean Meteorological Satellite (COMS) is planned to be launched onto Geostationary Earth Orbit in 2008. The meteorological imager (MI) is one of COMS payloads and has 5 spectral channels to monitor meteorological phenomenon around the Korean peninsular intensively and of Asian-side full Earth disk periodically. The MI has on-board radiometric calibration capabilities called 'blackbody calibration' for infrared channels and 'space look' for infrared/visible channels, and radiometric response stability monitoring device called 'albedo monitor' for visible channel. Additionally the MI has on-board function called 'electrical calibration' for the check of imaging path electronics of both infrared and visible channels. The characterization of MI performance is performed to provide the pre-launch radiometric calibration data which will be used for in-orbit radiometric calibration with the on-board calibration outputs. The radiometric calibration of the COMS MI is introduced in the view point of instrument side in terms of in-orbit calibration devices and capabilities as well as the pre-launch calibration activities and expected outputs.

• 전자통신동향분석
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• 제38권2호
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• pp.1-11
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• 2023

The recent explosion in the number of low earth orbit (LEO) satellites launched to space allows to easily anticipate that the number of satellites in orbit will sustain a dramatic increase. As satellite components are integrated and unified with terrestrial cellular networks, they will play a key role in providing coverage and resilience for future cellular networks. We provide a brief overview of typical scenarios and network architectures for cellular-based LEO satellite communication systems. In addition, we outline 3GPP standardization trends in non-terrestrial networks and satellite access based on 5G/5G Advanced systems and analyze future evolution prospects of cellular-based satellite communication systems.

• 한국지구과학회지
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• 제27권4호
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• pp.374-389
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• 2006

이 연구는 예비 중등 교사들을 대상으로 Lakatos의 방법론에 따라서 "계절 변화의 설명"에 대한 대안 모형을 조사하였다. 조사대상은 사범대학 과학교육학부 74명이다. 조사 결과 계절 변화에 대한 예비 중등 교사들의 설명은 과학적 모형과 불일치하는 대안 모형들을 가지고 있었다. 이러한 명백한 불일치의 대안 개념은 어떤 일관성 있는 방향으로, 자신들이 가지고 있는 대안 모형의 핵심 신념을 사용한다고 가정함으로서 설명되어 진다고 우리는 주장한다. 따라서 이 연구에서는 예비 교사들의 대안 모형을 극복하기 위해서 먼저 그들이 가지고 있다고 가정할 수 있는 핵심 신념들과 가능한 근원들을 알아보는 것이다. 그러한 근원들 중에서 교과서가 예비 교사의 대안 모형의 근원을 제공할 가능성을 배제할 수는 없다.

• 천문학회지
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• 제36권spc1호
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• pp.151-154
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• 2003

During the past decade the world solar physics community has made significant progress in understanding the Sun and its interaction with the heliosphere and Earth's magnetosphere. NASA in coordination and cooperation with many other countries has had impressive results with the SOHO, YOHKOH, POLAR, GEOTAIL, etc spacecraft. These successes have given us a sound foundation to proceed into the new century. The two current main efforts in the U.S. are the Solar Terrestrial Probes (STP) and Living With A Star (LWS) programs. The STP program is basically science driven with new missions being selected on the basis of basic science discovery. The LWS program is focused on understanding the basic physics of solar variability and its effects on Earth systems. The current plans for these two programs are discussed.

• 한국지구과학회지
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• 제30권5호
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• pp.550-564
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• 2009

When magnetotelluric (MT) data are obtained in the vicinity of the coast, the surrounding seas make it difficult to interpret subsurface structure, especially the deep part of the subsurface. We introduce an iterative method to correct the sea effect, based on the previous topographic correction method that removes the distortion due to topographic changes in seafloor MT data. The method first corrects the sea effect in observed MT impedance, and then inverts corrected response in a model space without the sea. Due to mutual coupling between the sea and the subsurface structure, the correction and inversion steps are iterated until the changes in each result become negligible. The method is tested for 1- and 2-D structures using synthetic MT data produced by 3-D forward modeling including surrounding seas. In all cases, the method closely recovers the true structure assumed to generate synthetic responses after a few iterations.

• 기술사
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• 제39권1호
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• pp.37-42
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• 2006

The scientific technology which develops day by day is realizing thedream of the human being. As thehumanuse the artificial intelligence computer and the robot. it is to become be convenient daily life and to live long healthy. and will enjoy the space trip as like as the overseas trip in 20years. However, the life of the human being shall be extended. become the older society and the population shall increase. stronger earth-quake and the typhoon shall occur more frequently due to global warming. I think that it will be anational concern that we perceive the age-quake approaches in the close of hand which is more terrible than the earth-quake, and prepare on it.

• 한국지반환경공학회 논문집
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• 제18권11호
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• pp.19-26
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• 2017

도심지에서 굴착 시 흔히 볼 수 있는 좁게 굴착된 경우 뒤채움이 되는 공간의 벽면은 대칭뿐 아니라 비대칭의 형태가 발생한다. 이러한 경우 뒤채움으로 인해 발생하는 수평응력은 벽면의 비대칭성 및 벽면의 마찰각에 따라 달라진다. 따라서 본 연구에서는 다양한 경계조건(저부폭, 벽면마찰, 뒤채움 지반의 상대밀도, 벽면경사)에 따른 깊이별 수평응력을 토조를 이용한 실내모형 실험을 통해 살펴보았다. 전체적으로 벽면이 매끄러울수록 경사가 수평에서 적을수록 수직응력의 증가로 인해 수평응력이 증가하였다.

• 천문학회보
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• 제41권1호
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• pp.75.4-76
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• 2016

DEEP-South (Deep Ecliptic patrol of the Southern sky) is one of the secondary science projects of KMTNet (Korea Microlensing Telescope Network). The objective of this project is twofold, the physical characterization and the discovery of small Solar System bodies, focused on NEOs (Near Earth objects). In order to achieve the goals, we are implementing a software package to detect and report moving objects in the $18k{\times}18k$ mosaic CCD images of KMTNet. In this paper, we present preliminary results of the moving object detection experiments using the prototype MODP (Moving Object Detection Program). We utilize multiple images that are being taken at three KMTNet sites, towards the same target fields (TFs) obtained at different epochs. This prototype package employs existing softwares such as SExtractor (Source-Extracto) and SCAMP (Software for Calibrating Astrometry and Photometry); SExtractor generates catalogs, while SCAMP conducts precision astrometric calibration, then MODP determines if a point source is moving. We evaluated the astrometric accuracy and efficiency of the current version of MODP. The plan for upgrading MODP will also be mentioned.