• 제목/요약/키워드: Land surveying

검색결과 555건 처리시간 0.021초

GPS-RTK를 이용한 수치지적도의 정확도 분석에 관한 연구 (A Study on the Accuracy Analysis of Numerical Cadastral Map by GPS-RTK)

  • 이대우;정영동;강상구;최한영
    • 대한공간정보학회지
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    • 제9권2호
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    • pp.47-54
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    • 2001
  • 본 연구는 토탈스테이션과 GPS측위 방법중 실시간이동측위(RTK) 방법으로 필지의 경계점 좌표를 관측하고, 두 성과를 비교, 분석하여 실시간이동측위 방법을 이용한 수치지적측량의 현지적용 가능성과 타당성 검토를 목적으로 연구를 수행하였다. 전남나주시의 경지정리지역에서 관측된 일필지 경계점 성과를 비교 분석한 결과 토탈스테이션 값을 기준으로 할 경우 X, Y축에서 평츈 변화값이 ${\Delta}X={\pm}0.02m,\;{\Delta}Y={\pm}0.02m$로 매우 미소한 차이를 나타났고, 일 필지 경계점 좌표를 수치지적도로 표시하여 비교한 결과 그 차이가 허용오차 이내에서 나타났다. 이상과 같이 실무에서 사용되는 토탈스테이션에 의한 관측 성과와 GPS실시간이동측위 방법에 의한 성과의 차가 허용오차 이내에서 미소하게 발생하여 GPS실시간이동측위 방법이 시간적으로나 경제적으로 효과적인 방법으로 판단되었다.

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Identification of the Anthropogenic Land Surface Temperature Distribution by Land Use Using Satellite Images: A Case Study for Seoul, Korea

  • Bhang, Kon Joon;Lee, Jin-Duk
    • 한국측량학회지
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    • 제35권4호
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    • pp.249-260
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    • 2017
  • UHI (Urban Heat Island) is an important environmental issue occurring in highly developed (or urbanized) area such as Seoul Metropolitan City of Korea due to modification of the land surface by man-made structures. With the advance of the remote sensing technique, land cover types and LST (Land Surface Temperature) influencing UHI were frequently investigated describing that they have a positive relationship. However, the concept of land cover considers material characteristics of the urban cover in a comprehensive way and does not provide information on how human activities influence on LST in detail. Instead, land use reflects ways of land use management and human life patterns and behaviors, and explains the relationship with human activities in more details. Using this concept, LST was segmented according to land use types from the Landsat imagery to identify the human-induced heat from the surface and interannual and seasonal variation of LST with GIS. The result showed that the LST intensity of Seoul was greatest in the industrial area and followed by the commercial and residential areas. In terms of size, the residential area could be defined as the major contributor among six urban land use types (i.e., residential, industrial, commercial, transportation, etc.) affecting UHI during daytime in Seoul. For temperature, the industrial area was highest and could be defined as a major contributor. It was found that land use type was more appropriate to understand the human-induced effect on LST rather than land cover. Also, there was no significant change in the interannual pattern of LST in Seoul but the seasonal difference provided a trigger that the human life pattern could be identified from the satellite-derived LST.

Land cover classification using LiDAR intensity data and neural network

  • Minh, Nguyen Quang;Hien, La Phu
    • 한국측량학회지
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    • 제29권4호
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    • pp.429-438
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    • 2011
  • LiDAR technology is a combination of laser ranging, satellite positioning technology and digital image technology for study and determination with high accuracy of the true earth surface features in 3 D. Laser scanning data is typically a points cloud on the ground, including coordinates, altitude and intensity of laser from the object on the ground to the sensor (Wehr & Lohr, 1999). Data from laser scanning can produce products such as digital elevation model (DEM), digital surface model (DSM) and the intensity data. In Vietnam, the LiDAR technology has been applied since 2005. However, the application of LiDAR in Vietnam is mostly for topological mapping and DEM establishment using point cloud 3D coordinate. In this study, another application of LiDAR data are present. The study use the intensity image combine with some other data sets (elevation data, Panchromatic image, RGB image) in Bacgiang City to perform land cover classification using neural network method. The results show that it is possible to obtain land cover classes from LiDAR data. However, the highest accurate classification can be obtained using LiDAR data with other data set and the neural network classification is more appropriate approach to conventional method such as maximum likelyhood classification.

지능형국토정보 테스트베드 설계에 대한 연구 - 측량장비를 중심으로 - (Research on the Design of Korea Land Spatialization Program's Test-bed - Focused on Surveying Equipments -)

  • 송기성;박재민;우희숙;김병국
    • 대한공간정보학회지
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    • 제19권3호
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    • pp.99-105
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    • 2011
  • 지능형국토정보기술혁신사업은 상용화가 가능한 공간정보기술개발을 위해 2006년부터 2012년까지 정부가 추진하고 있는 대형 국가R&D사업이다. 본 사업은 연구 성과물이 실제 현장에 바로 적용될 수 있는 검증된 연구 성과물을 도출하기 위해 세종시를 테스트베드 지역으로 선정하여, 현장실험을 준비하고 있다. 그러나 효과적인 연구 성과물 현장실험을 위해서는 국내외에서 인정받을 수 있는 기준을 만족하는 현장여건을 조성해야 한다. 본 논문에서는 지능형국토정보기술혁신사업의 연구성과물 중 최신 측량장비의 성능 검증을 위한 다양한 요구사항과 세종시 현장여건을 고려하여 테스트베드를 설계하는데 목적을 두었다.

Application of Multi-Antenna GPS Technology in Monitoring Stability of Slopes

  • Ding, X.L.;Dai, W.J.;Yang, W.T.
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.651-659
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    • 2009
  • There are a great number of man-made and natural slopes in many parts of the world including Hong Kong and Mainland China. For example, there are over 40,000 slopes in Hong Kong registered by the Hong Kong Government. Landslides due to slope failures can often cause catastrophes that involve the loss of both lives and important facilities. GPS has been demonstrated to have great potentials for use in monitoring slope stability and landslides. However, the high hardware cost of GPS has limited the wide spread use of GPS for such applications. The multi-antenna GPS technology initiated by the research group and our collaborators has significantly reduced the cost of GPS and provided a solution to a number of associated problems such as data management and power supply. This paper discusses practical applications of multi-antenna GPS technology in slope monitoring, including system design, setting up, data transmission and management, and data quality analysis and control. Some slope monitoring examples are given to illustrate the points discussed.

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Filtered-based GPS structural vibration monitoring methods and comparison of their performances

  • Zhong, P.;Ding, X.L.;Zheng, D.W.;Chen, W.
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.137-141
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    • 2006
  • The purpose of GPS structural vibration monitoring is to obtain information on the frequency and amplitude of vibrations based on GPS observations that are often affected by various errors. Filters are frequently used to improve GPS accuracy and to retrieve vibration signals from GPS observational series. This paper studies the performances of four commonly used filters, i.e., Vondrak, wavelet, adaptive FIR and Kalman filters, for such applications. Controlled experiments are carried out and the results show that the capability of GPS in tracking structural dynamics and complex signals can be improved with any of the filters. The performances of Vondrak and wavelet filters are almost the same and superior to the adaptive FIR and Kalman filters. Recommendations are given for the selection of filters and filter parameters for different situations based on an analysis of the advantages and disadvantages of each of the filters.

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RTK-GPS와 CAD 결합에 의한 현지측량의 구현 (Realization of Field Surveying on AutoCAD Using RTK-GPS)

  • 강준묵;김홍진;조성호
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 춘계학술발표회논문집
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    • pp.145-150
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    • 2004
  • In this paper, development of automation system for real time cadastral surveying and mapping is studied. This system is composed of interface between pc and GPS receiver, input-output-store of positioning information by RTK-GPS surveying. Also coordinates of surveying is displayed on CAD. As a results of this application on the field, transformed coordinates of points are displayed on the map at the real time as surveying. This system is applied to construct coordinate information for a parcel of land, and this could be specially used to realize the information of boundary points in the field.

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Impacts of Urban Land Cover Change on Land Surface Temperature Distribution in Ho Chi Minh City, Vietnam

  • Le, Thi Thu Ha;Nguyen, Van Trung;Pham, Thi Lan;Tong, Thi Huyen Ai;La, Phu Hien
    • 한국측량학회지
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    • 제39권2호
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    • pp.113-122
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    • 2021
  • Urban expansion, particularly converting sub-urban areas to residential and commercial land use in metropolitan areas, has been considered as a significant signal of regional economic development. However, this results in urban climate change. One of the key impacts of rapid urbanization on the environment is the effect of UHI (Urban Heat Island). Understanding the effects of urban land cover change on UHI is crucial for improving the ecology and sustainability of cities. This research reports an application of remote sensing data, GIS (Geographic Information Systems) for assessing effects of urban land cover change on the LST (Land Surface Temperature) and heat budget components in Ho Chi Minh City, where is one of the fastest urbanizing region of Vietnam. The change of urban land cover component and LST in the city was derived by using multi-temporal Landsat data for the period of 1998 - 2020. The analysis showed that, from 1998 to 2020 the city had been drastically urbanized into multiple directions, with the urban areas increasing from approximately 125.281 km2 in 1998 to 162.6 km2 in 2007, and 267.2 km2 in 2020, respectively. The results of retrieved LST revealed the radiant temperature for 1998 ranging from 20.2℃ to 31.2℃, while that for 2020 remarkably higher ranging from 22.1℃ to 42.3℃. The results also revealed that given the same percentage of urban land cover components, vegetation area is more effective to reduce the value of LST, meanwhile the impervious surface is the most effective factor to increase the value of the LST.

드론항공사진측량을 활용한 지적측량 성과결정에 관한 연구 (A Study on Decision Making of Cadastral Surveying Results using Drone Photogrammetry)

  • 임성하;김호종;이돈선
    • 지적과 국토정보
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    • 제51권1호
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    • pp.79-95
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    • 2021
  • 본 연구는 지적측량 단계 중 가장 중요하지만, 객관적이지 못하고 주관에 의해 측량자의 오판이나 실수가 발생할 수 있는 개연성이 큰 지적측량 성과결정 단계에서 드론사진측량을 기반으로 지적측량성과 결정의 적용성을 평가하였다. 드론사진측량 결과물에서 경계점 추출의 정확도를 판단하기 위한 실험에서는 2D와 3D영상에서 추출한 22개 필지의 자표면적과 지상측량 좌표면적을 비교하여 그 차이가 2D영상은 RMSE가 1.44m2, 3D영상은 0.32m2로 정량화할 수 있었다. 또한, 정사영상을 기반으로 지적측량 성과결정을 평가하기 위한 실험에서는 자료조사를 통한 기존 측량성과 결정량과 비교하여 RMSE가 N방향으로 0.346m, E방향으로 0.296m로 나타났다. 이러한 실험결과로 미루어 볼 때 도해지역에서 정사영상기반의 성과 결정시 약 0.3m 내외의 정확도로 현지 측량없이 성과결정이 이루질 수 있으며, 이는 자료조사 및 지상측량과 더불어 정사영상이 활용된다면, 지적측량성과 결정 과정을 더 객관화하여 개인오차를 줄일 수 있다고 판단된다.