• 제목/요약/키워드: Terrain data

검색결과 945건 처리시간 0.025초

Landsat 영상을 이용한 서해안 지형 변화 추이 분석 (An Analysis on the change in Topography in the West Coast Using Landsat Image)

  • 강준묵;윤희천;강영미
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.275-279
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    • 2004
  • This study was done to detect the topographic and terrain change of the vicinity of the west coast. To make the basic map of the change in topology and terrain, the mosaic images were made using the images from the satellite, which were given the geometric correction based on the GCP (Ground Control Point) and DEM (Digital Elenation Model) data. The accuracy of the images was examined by .empaling them with CCP through 1:25,000's digital map. After that, among the resultant images of the 1970s and 2000s, those of Sihwa, Hwaong and Ansan, the lands reclaimed by drainage were compared to observe the change in the area. From this study, the accuracy of the images of the west coast from satellite could be acquired and the change of the topology and terrain was detected effectively. From the results, it was known that, in case of the land the topological change was not so big due to the development in the reclaimed land or the bare land. In Sihwa, the size of the land was increased 180 $\textrm{km}^2$ and that of the seashore was decreased 110 km. in Hwaong the size was increased 50 $\textrm{km}^2$ and in Ansan the city space was increased 71 $\textrm{km}^2$ due to the formation of the industrial complex.

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오프로드 환경에서 효율적인 6족 로봇 보행 시스템 개발 (Development of an Effective Walking System for a Hexapod Robot on Uneven Terrain)

  • 김준우;이기원;이석규
    • 제어로봇시스템학회논문지
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    • 제19권12호
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    • pp.1152-1159
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    • 2013
  • This paper proposes an effective walking system for a hexapod robot on uneven terrain. To overcome the deficiencies of two-pair walking systems, which are effective on even terrain, the use of only three legs changes the steps required for movement. The proposed system receives feedback data from switches attached to the bottom of the legs and gyro sensor to carry out stable walking using the Bezier curve algorithm. From the coordinates of the Bezier curve, which guarantees the circular motion of legs, the motor's angle value can be obtained using inverse kinematics. The angle values are sent to each motor though RS-485 communication. If a switch is pushed by the surface during navigation in the Bezier curve pattern, the robot is designed to change its circular course. Through the changed course, each leg can be located on an optimal surface and the wobble phenomenon is reduced by using a normal vector algorithm. The simulation and experiment results show the efficiency of the proposed algorithm.

육.해도 통합수치도 제작 기술 개발과 응용 방안 (A Study on the Technology Development and Application Plan for Making an Integrated Digital Map of an Electronical Navigational Chart and a Digital Terrain Map)

  • 이기철;박창호;서상현;김정희;정희균
    • 한국항만학회지
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    • 제14권2호
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    • pp.209-217
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    • 2000
  • This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coastal area.

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육.해도 통합수치도 제작 기술 개발과 응용 방안+ (A Study on the Technology Development and Application Plan for making an Integrated Digital Map of an Electronical Navigational Chart and a Digital Terrain Map)

  • 이기철;정희균;박창호;서상현;김정희
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 1999년도 추계학술대회논문집
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    • pp.347-356
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    • 1999
  • This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coast area.

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Geospatial analysis of wind velocity to determine wind loading on transmission tower

  • Hamzah, Nur H.;Usman, Fathoni
    • Wind and Structures
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    • 제28권6호
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    • pp.381-388
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    • 2019
  • This paper described the application of Geospatial Analysis in determining mean wind speed, $V_h$ for wind load calculation imposed to electrical transmission tower structural design. The basic wind speed data on available station obtained from Malaysian Meteorology Department is adjusted by considering terrain and ground roughness factor. The correlation between basic wind speed, terrain factor and ground roughness stated in EN-50341-1 is used to obtain the $V_h$ for overhead transmission line elements 50 m above ground. Terrain factor, $k_r$ and ground roughness, $z_0$ in this study are presented by land use types of study area. Wind load is then calculated by using equation stated in design code EN-50341-1 by using the adjusted mean wind speed. Scatter plots of $V_h$ for different $k_r$and $z_0$ are presented in this paper to see the effect of these parameters to the value of $V_h$. Geospatial analysis is used to represent the model of $V_h$. This model can be used to determine possible area that will subject to wind load which severe to the stability of transmission tower and transmission line.

항공사진을 이용한 3차원 경관도 제작 (Generation of 3-Dimensional Landscape Map from Aerial Photos)

  • 유복모;정수;김원대
    • 대한공간정보학회지
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    • 제3권1호
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    • pp.105-113
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    • 1995
  • 지형을 분석하는 데 있어서 3차원 경관도는 실제의 지형을 직접 보는 것과 같은 효과를 주므로 매우 유용한 자료로 이용된다. 일반적으로 3차원 경관도가 필요한 경우에는, 높은 지역에서 대상지역을 바라보며 촬영을 하거나, 대상지역의 범위 또는 지상촬영조건 등에 따라 항공기를 이용해 관측시점을 높여 전체 대상지를 촬영하는 등의 방법으로 경관사진을 취득하여 이용하였다. 그러나 이 방법은 다방면으로부터 다양한 고도에서의 사진이 요구될 경우에는 많은 양의 촬영이 필요할 뿐만 아니라 추가적인 촬영을 시행하여야 하는 경우도 있을 수 있다. 또한 사진기의 중심투영원리에 의해 촬영된 사진 상의 위치관계가 실체의 위치관계와 다르게 나타나므로 정확한 위치관계를 파악하기 곤란하다. 이 연구는 항공측량용 사진기에 의해 수직촬영된 입체사진을 이용하여 실제의 지형형상과 유사한 3차원 경관도를 컴퓨터 상에서 수치사진측량기법을 적용하여 제작하는 방법을 제시하였다. 이는 지형공간정보체계의 다양한 기능 중에서 3차원 지형분석을 위한 유용한 자료를 제공해 줄 수 있을 것이다.

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분산계수의 전처리에 의한 대기분산모델 성능의 개선 (Improvement of Atmospheric Dispersion Model Performance by Pretreatment of Dispersion Coefficients)

  • 박옥현;김경수
    • 한국대기환경학회지
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    • 제23권4호
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    • pp.449-456
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    • 2007
  • Dispersion coefficient preprocessing schemes have been examined to improve plume dispersion model performance in complex coastal areas. The performances of various schemes for constructing the sigma correction order were evaluated through estimations of statistical measures, such as bias, gross error, R, FB, NMSE, within FAC2, MG, VG, IOA, UAPC and MRE. This was undertaken for the results of dispersion modeling, which applied each scheme. Environmental factors such as sampling time, surface roughness, plume rising, plume height and terrain rolling were considered in this study. Gaussian plume dispersion model was used to calculate 1 hr $SO_2$ concentration 4 km downwind from a power plant in Boryeung coastal area. Here, measured data for January to December of 2002 were obtained so that modelling results could be compared. To compare the performances between various schemes, integrated scores of statistical measures were obtained by giving weights for each measure and then summing each score. This was done because each statistical measure has its own function and criteria; as a result, no measure can be taken as a sole index indicative of the performance level for each modeling scheme. The best preprocessing scheme was discerned using the step-wise method. The most significant factor influencing the magnitude of real dispersion coefficients appeared to be sampling time. A second significant factor appeared to be surface roughness, with the rolling terrain being the least significant for elevated sources in a gently rolling terrain. The best sequence of correcting the sigma from P-G scheme was found to be the combination of (1) sampling time, (2) surface roughness, (3) plume rising, (4) plume height, and (5) terrain rolling.

EGMs의 지형보정에 따른 국내 지역별 지오이드고 연구 (A Study on Geoid Height of Provinces in South Korea by Terrain correction of Earth Gravitational Models)

  • 이용창
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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    • pp.942-946
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    • 2007
  • 최근 새로운 지구중력장 모델의 개발로 인하여 중력관련 응용분야의 향상된 연구결과가 기대되고 있다. 본 연구는 지구중력장 모형으로부터 남한지역에 대한 고도이상(height anomalies)를 산정하고 지형보정 여부에 따른 지역별 지오이드고의 특성을 분석하여 국내 지오이드고 개발연구에 기여하고자 한다. 이를 위하여 다양한 중력 관측 자료를 조합한 5가지 지구중력장모형과 지형보정을 위한 ETOPO2모형을 선정하고 남한지역의 경 위도 $1^{\circ}{\times}1^{\circ}$ 6개 육상부 및 4개 해상부에 대한 30"격자의 지오이드고를 산정한 후, 국립해양조사원의 NORI-05모델에 의한 결과와 비교하였다. 육상부의 경우, GPS 관측이 수행된 수준점 50측점 및 삼각점 30측점을 점검점으로 선정하여 GPS/Leveling, NORI-05 및 5가지 지구중력장모형에 의한 지오이드고를 비교 분석하였다. 연구결과, EIGEN-CG03C 및 EIGEN-CG04C 중력장모형이 GPS/Leveling 결과에 근접함을 보였고 국내 정밀 지오이드고를 산정할 경우, 육상 및 해상에서 지형의 요철이 심한 지역일수록 정밀한 지형보정의 필요성을 확인할 수 있었다.

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여수지역 대기확산의 수치 모사 -I. 지형의 영향- (Simulation of Atmospheric Dispersion over the Yosu Area -I. Terrain Effects-)

  • 김영성;오현선
    • 한국대기환경학회지
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    • 제16권3호
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    • pp.211-223
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    • 2000
  • The atmospheric dispersion of a pollutant emitted from a hypothetical source located in the middle of the Yochon Industrial Estate was simulated by using the Regional Atmospheric Modeling System (RAMS). Four horizontally nested grids were employed: the coarsest one covered the southern part of the Korean Peninsula including Mt. Chiri and the finest one covered the Yochon Industrial Estate and the surrounding area. Wind fields were initially assumed horizontally homogeneous with a wind speed of 4m/s, the average for the Yosu area, and were developed without both external forces and diurnal changes in order to investigate the terrain-induced phenomena. Wind directions that could emphasize the terrain effects on the pollutant transport and that could carry pollutants to a highly-popluated area were selected for the dispersion study. A pollutant was released for 24hours from a grid-base volume source after a 24-h blank run for developing the wind field. The dispersion study showed that the pollutant from the present source location did not directly affect the Yosu City, but showed high concentrations at locations behind the hills 5 to 6 km away from the source according to wind directions. When the wind speed was low, close to calm condition, the pollutant was detected at upstream locations 6 to 7 km from the source. In comparison with the results from the RAMS simulation, the Industrial Source Complex Short-Term Model(ISCST3) predicted a narrow dispersion that was sensitive to the wind direction. When the wind velocity was affected by the local environment, the ISCST3 calculation using that data also gave a lop-sided result, which was different from the distribution of the pollutant reproduced by RAMS.

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등고선을 이용한 자행정보의 3차원 시각화 기법 (A 3-D Visualization Method for Geographical Information based on Contour Lines)

  • 한정규;백중환;황수찬
    • 한국항행학회논문지
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    • 제5권2호
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    • pp.123-133
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    • 2001
  • 기존의 위성 영상이나 지도 이미지를 이용한 지형의 3차원 시각화 방법은 전처리 과정이 복잡하고 3차원 지형의 생성에 필요한 데이타가 방대하다는 단점이 있다. 따라서 본 논문에서는 수치지도를 이용하여 등고선 정보를 획득하고 이를 바탕으로 3차원 지형을 자동으로 생성할 수 있는 지형의 3차원 시각화 방법을 제시하고자 한다. 또한 지형 데이타의 3차원 시각화를 위해 반드시 처리해야 하는 세가지 문제인 등고선 대응 문제, 타일링 문제, 지맥 문제를 효율적으로 처리할 수 있는 방법을 소개한다. 이를 위해 가상 등고선의 개념을 정의하고 왜곡된 등고선을 대응되는 등고선과 유사한 모양이 되도록 확장하여 3차원 표면을 생성할 수 있도록 한다. 이 방법은 3차원 지형을 정확하고 세밀하게 표현할 수 있는 장점이 있다.

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