• Title/Summary/Keyword: 가상위성

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Service Coverage Analysis on Land-based DGPS Station due to Output Power Enhancement (송신출력 증강에 따른 내륙 DGPS 기준국의 서비스 영역 분석)

  • Baek, Hwa-Jong;Kim, Young-Wan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1350-1357
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    • 2012
  • Korean NDGPS, which consists of the ocean-based reference station of 11 site and the land-based reference station of 6 sites, are operating. The land-based reference stations provide the output power of 500W, the service shadow regions are occurred due to mountains and nation topography. In this paper, the service coverages of land-based reference stations are analyzed in the viewpoint of output power enhancements of land-based reference stations within 1KW. Also, we suggest virtual land DGPS reference stations 2 sites to resolve the service shadow regions.

3D Terrain Analysis and Modeling for Double-Tract Railway Route of Forest Sites (산악지 복선 철도노선에서의 3차원지형분석 및 모델링)

  • Yeon, Sang-Ho
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.892-899
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    • 2004
  • Recently remote sensing technology is applied for construction projects planning and design areas by use of remote sensed satellite images according to engineering application technology in the various experimental tasks. In this study, It was applied for 3 dimensional terrain analysis and basic design by comparing to present railway and new expand doble-tract railway route of forest sites on the new construction site of 15km at national railway lines,. and then showed 3-D perspective images and fly simulation images to possibility for various application as terrain analysis modeling and running simulation at the course. As a results of its applied, It gained the results not only improvement of present methods but also real various application possibilities.

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Design and Implementation of OBCP Engine based on Lua VM for AT697F/VxWorks Platform (AT697F/VxWorks 플랫폼에서 Lua 가상머신 기반의 OBCP 엔진 설계 및 구현)

  • Choi, Jong-Wook;Park, Su-Hyun
    • Journal of Satellite, Information and Communications
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    • v.12 no.3
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    • pp.108-113
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    • 2017
  • The OBCP called 'operator on board' is that of a procedure to be executed on-board, which can be easily be loaded, executed, and also replaced, without modifying the remainder of the FSW. The use of OBCP enhances the on-board autonomy capabilities and increases the robustness to ground stations outages. The OBCP engine which is the core module of OBCP component in the FSW interprets and executes of the procedures based on script language written using a high-level language, possibly compiled, and it is relying on a virtual machine of the OBCP engine. FSW team in KARI has studied OBCP since 2010 as FSW team's internal projects, and made some OBCP engines such as Java KVM, RTCS/C and KKOMA on ERC32 processor target only for study. Recently we have been studying ESA's OBCP standard and implementing Lua and MicroPython on LEON2-FT/AT697F processor target as the OBCP engine. This paper presents the design and implementation of Lua for the OBCP engine on AT697F processor with VxWorks RTOS, and describes the evaluation result and performance of the OBCP engine.

Analysis of Utilization Status about National GNSS Infrastructure Linked to Precise Positioning Service (정밀 위치결정 서비스에 연계한 국가 GNSS 인프라 활용현황 분석)

  • Park, Joon-Kyu;Jung, Kap-Yong
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.2
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    • pp.401-408
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    • 2017
  • GNSS(Global Navigation Satellite System) is positioning and navigation system using satellites. Accurate positioning is possible in all regions of the world using satellite signals. In Korea, GPS was introduced in the late 1980s. GPS is used in research and work in various fields such as navigation, surveying, and GIS. Since 1995, NGII(National Geographic Information Institute) has installed and operated CORS(Continuously Operating Reference Station) for the practical use of GNSS surveying, RINEX download and VRS(Virtual Reference Station) service was provided for precise positioning. Demand for these services is explosively increasing in the field of surveying. Therefore, there is a need for research to provide good service. In this study, status of national surveying infra structure was researched focused on CORS and its services. As a results, current status of CORS and service were presented. Users of VRS service has increased greatly. In order to provide stable service and advanced surveying, it is necessary to continuously upgrade services such as providing services for various GNSS satellites and securing stability through server redundancy in the data center.

Extraction of 3D Building Information using Shadow Analysis from Single High Resolution Satellite Images (단일 고해상도 위성영상으로부터 그림자를 이용한 3차원 건물정보 추출)

  • Lee, Tae-Yoon;Lim, Young-Jae;Kim, Tae-Jung
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.2 s.36
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    • pp.3-13
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    • 2006
  • Extraction of man-made objects from high resolution satellite images has been studied by many researchers. In order to reconstruct accurate 3D building structures most of previous approaches assumed 3D information obtained by stereo analysis. For this, they need the process of sensor modeling, etc. We argue that a single image itself contains many clues of 3D information. The algorithm we propose projects virtual shadow on the image. When the shadow matches against the actual shadow, the height of a building can be determined. If the height of a building is determined, the algorithm draws vertical lines of sides of the building onto the building in the image. Then the roof boundary moves along vertical lines and the footprint of the building is extracted. The algorithm proposed can use the shadow cast onto the ground surface and onto facades of another building. This study compared the building heights determined by the algorithm proposed and those calculated by stereo analysis. As the results of verification, root mean square errors of building heights were about 1.5m.

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Urban Vitality Assessment Using Spatial Big Data and Nighttime Light Satellite Image: A Case Study of Daegu (공간 빅데이터와 야간 위성영상을 활용한 도시 활력 평가: 대구시를 사례로)

  • JEONG, Si-Yun;JUN, Byong-Woon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.4
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    • pp.217-233
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    • 2020
  • This study evaluated the urban vitality of Daegu metropolitan city in 2018 using emerging geographic data such as spatial big data, Wi-Fi AP(access points) and nighttime light satellite image. The emerging geographic data were used in this research to quantify human activities in the city more directly at various spatial and temporal scales. Three spatial big data such as mobile phone data, credit card data and public transport smart card data were employed to reflect social, economic and mobility aspects of urban vitality while public Wi-Fi AP and nighttime light satellite image were included to consider virtual and physical aspects of the urban vitality. With PCA (Principal Component Analysis), five indicators were integrated and transformed to the urban vitality index at census output area by temporal slots. Results show that five clusters with high urban vitality were identified around downtown Daegu, Daegu bank intersection and Beomeo intersection, Seongseo, Dongdaegu station and Chilgok 3 district. Further, the results unveil that the urban vitality index was varied over the same urban space by temporal slots. This study provides the possibility for the integrated use of spatial big data, Wi-Fi AP and nighttime light satellite image as proxy for measuring urban vitality.

The Effect of Auditory Cue on Searching Task of Songs (소리의 청각적 정보가 곡 탐색에 미치는 영향)

  • Ryu, Hyung-Su;Kim, Jong-Wan;Han, Kwang-Hee
    • 한국HCI학회:학술대회논문집
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    • 2007.02b
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    • pp.535-540
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    • 2007
  • 최근 음악을 재생할 수 있는 다양한 소형기기들의 발전이 이루어지고 있다. 휴대용 음향기기에서 곡을 탐색할 경우, 곡 탐색 습관의 특성상 눈으로 확인하지 않고 손을 사용한 촉각적 피드백만을 이용하는 것이 대부분이다. 또한 곡 탐색 과제는 청각적인 표적을 찾는 것임에 반하여, 지금까지 청각적인 단서에 대한 연구의 대부분은 시각적인 표적을 찾는 것에 집중되어 있었다. 본 연구에서는 청각적인 표적을 탐색하는데 있어 청각적 위치 단서가 미치는 영향을 알아보고자 하였다. 주어진 곡 리스트를 암기한 후, 화면에 제시되는 표적 곡을 탐색하는데 있어 청각적인 위치 단서가 있는 좌우 조건, 가운데 조건, 그리고 무음 조건의 경우에 따른 곡 탐색의 정확률과 반응 시간을 측정하였다. 과제는 정상과 오류 두 가지 유형으로 구성되었다. 결과는 청각적인 위치 정보가 포함된 좌우 조건이 정상 과제와 오류 과제에 있어서 가운데 조건과 무음 조건에 비하여 모두 유의미하게 짧은 반응 시간을 보였다. 본 실험 결과는 휴대용 음향기기뿐만 아니라 위성항법장치(GPS), 가상환경(Virtual Environment) 등과 같이 청각적인 표적을 찾아야 하는 과제를 포함하는 환경에도 적용될 수 있을 것이다.

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Trend of Multi-sensor Spatial Imagery Processing Technology (멀티센서 공간영상정보 통합처리 기술개발 동향)

  • Kim, K.O.;Shin, S.W.;Lim, Y.J.;Kim, H.G.;Oh, J.H.
    • Electronics and Telecommunications Trends
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    • v.20 no.3 s.93
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    • pp.92-103
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    • 2005
  • 멀티센서 공간영상정보 통합처리 기술은 인공 위성, 항공기 등에 탑재된 여러 가지의 센서에서 취득되는 공간영상 데이터를 통합 처리하여 고품질의 공간정보 생성을 가능케 해주는 신기술이다. 기존의 개별센서 처리 기술이 가지는 개개의 장점만을 융합하여 3차원 가상현실 공간 구성, 디지털 지도 자동 제작, 방재, 환경 등의 분야에서 사용되는 공간 데이터를 생성해낼 수 있는 장점을 지닌다. 본 고에서는 멀티센서 통합처리기술의 동향과 기술의 내용에 대하여 살펴보고, 통합처리 기술이 어떻게 활용되는지에 대한 내용을 소개한다.

A Study on the Numbering Plane for IMT-2000 (IMT-2000 번호계획)

  • 조용환;황진수;한운영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.6
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    • pp.1619-1626
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    • 1998
  • In this paper, we made researches into considerations for the numbering plan for IMT-2000 that seems to be a unit system integrating cellular, satellite, PCS. The purposes of the numbering plane for IMT-2000 ARE SIMILAR TO IMT-2000 evolution form:constructing the numbering plane centering around UPT as a PRE-FPLMTS from and futhermore, adding terminal mobility to IMT-2000. For this paper, we established three numbering plans for IMT-2000 that accepts various considerations.

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우주배경복사 온도비등방성 파워스펙트럼의 셋째 봉우리에 나타난 남북 이상

  • Go, Gyeong-Yeon
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.45.2-45.2
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    • 2011
  • WMAP이 7년 동안 관측해 얻은 우주배경복사의 온도비등방성 지도로부터 파워스펙트럼을 측정하는 프로그램을 개발하였다. WMAP의 가상관측 자료를 분석하여 파워스펙트럼이 제대로 측정되는지를 시험하였으며, 실제 WMAP 자료에서 측정한 파워스펙트럼이 WMAP팀의 결과와 통계적으로 일치함을 확인하였다. 본 연구에서는 천구를 다양한 영역으로 나누어 파워스펙트럼을 측정해 보았다. 특히, 남, 북반구의 은위 30도 이상 영역에서 측정한 파워스펙트럼을 비교한 결과, 셋째 봉우리가 남(북)반구에서 상대적으로 높(낮)게 나타났으며 봉우리 높이의 남북 차이는 표준 ${\Lambda}CDM$ 우주모형으로 분석하여 보면 $3{\sigma}$ 정도의 통계적인 유의성을 보였다. 이러한 남북 이상(anomaly)의 원인으로서 WMAP의 기기 잡음, 우리은하의 방출선, 은하 외부적인 점광원에 의한 오염 가능성을 조사하고 토의하였다. 파워스펙트럼의 셋째 봉우리는 WMAP 해상도의 한계 지점이며 기기 잡음이 우세한 지역이므로, WMAP의 자료만으로 검출된 남북 이상의 원인을 찾기에는 한계가 있다. 앞으로 Planck 위성의 관측 자료가 공개되면 그 원인이 규명이 될 수 있을 것으로 예상된다.

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