• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2010.04a
• /
• pp.423-427
• /
• 2010

현재 GPS/INS 운영 방법은 일정한 범위 내에 GPS 지상기준국을 설치하도록 되어있다. 그러나 촬영지역이 넓을 경우나 작업의 우선순위 등에 따라 지상기준국의 운영이 곤란한 상황이 발생할 수 있으며, 작업자의 실수, 수신기의 오류 등으로 지상기준국을 항상 안정적으로 운영하기 어렵다. 이에 본 연구에서는 국토지리정보원의 GPS 상시관측소를 활용하여 항공레이저측량 원시자료를 구축하고, 지상 기준국을 사용한 결과와의 비교를 통해 기준국이 항공레이저측량 결과에 미치는 영향을 분석하고자하였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.25 no.3
• /
• pp.183-190
• /
• 2007

To make use of surveying data obtained from different sensors and different techniques, it is a pre-requite step that register them in a common coordinate system. For this purpose, we developed methodologies to register IKONOS-2 Satellite Imagery using LiDAR(Light Detection And Ranging) data. To achieve this, conjugate features from these data should be extracted in advance. In this study, linear features are chosen as conjugate features. Then, to register them, observation equations are established from similarity measurements of the extracted features and the results was evaluated statistically. The results clearly demonstrate that the proposed algorithms are appropriate to register these data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.23 no.4
• /
• pp.359-366
• /
• 2005

Airborne LiDAR integrated with on-board GPS/INS and scanning technology is a state-of the-art system for direct 3D geo-spatial data acquisition. In this study, LiDAR data were calibrated using ground points in calibration site for the higher system accuracy. The accuracy results are ${\pm}15{\sim}30\;cm$ in horizontal and ${\pm}15\;cm$ in vertical. The results show that LiDAR system has capability for precise DEM and contour generation, 3D urban modeling and engineering design.

• Journal of Korean Society for Geospatial Information Science
• /
• v.14 no.4 s.38
• /
• pp.37-44
• /
• 2006

To use surveying data obtained from different sensors and different techniques, it is a pre-requite step that register them in a common coordinate system. For this purpose, we developed methodologies to register airborne photos, ALS (Airborne Laser Scanning) data and digital maps. To achieve this, conjugate features from these data should be extracted in advance. In this study, linear features are chosen as conjugate features. Based on such a selection strategy, a simple and robust algorithm is proposed for extracting such features from ALS data. Then, to register them, observation equations are established from similarity measurements of the extracted features and the results was evaluated statistically. The results clearly demonstrate that the proposed algorithms are appropriate to register these data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.28 no.3
• /
• pp.299-304
• /
• 2010

Depending on the progress of the surveying and information processing technology, the rapidly developing field of spatial information and the 3D real world spatial information for a variety of content on the computer was able to easily access. In this research, to study on the spot or to use aerial photographs to measure trees of the acquired data, calculate the trees height, forest area and capacity, determine the distribution of the density of acquired points in the forest and analyze accurate and objective information was acquired. The United States, Canada and so on through the capacity of trees biomass, forest resource analysis, time series monitoring, wildfire behavior modeling and applied research and has been declared. During worldwide is increasing interest in forest resources. In nationally, extensive research and analysis of the forest consists of the correct management and protection of forest resources to be effective.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.3D
• /
• pp.437-444
• /
• 2008

In the paper, a methodology is verified to integrate IKONOS-2 satellite imagery and ALS dataset by compensating biases of RPC models. To achieve this, conjugate features from both data should be extracted in advance. For this purpose, linear features are chosen as conjugate features because they can be accurately extracted from man-made structures in urban area and more easily extracted than point features from ALS data. Then, observation equations are established from similarity measurements of the extracted features. During the process, several kinds of transformation functions were selected and used to register them. In addition, it was also analyzed how the number of linear features used as control features affects the accuracy of registration results. Finally, the results were evaluated by using check-points obtained from DGPS surveying techniques and it was clearly demonstrated that the proposed algorithms are appropriate to integrate these data.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2009.04a
• /
• pp.291-292
• /
• 2009

항공레이저측량(LiDAR)는 대상물에 반사되어 오는 레이저를 이용하여 멀리 위치한 대상물의 정보를 측정하는 광학원격탐사기술이다. 항공기에 레이저센서를 장착, 지표면에 레이저 펄스를 주사하여 반사된 펄스의 도달시간을 측정, 반사지점의 3차원 위치좌표를 계산하여 지표면의 정보를 추출한다. 항공레이저측량(LiDAR)는 재난재해관리, 도로 및 교통, 시설물계획관리, 지역지구 계획 등에 활용할 수 있다. 또한 항공사진과 GIS를 활용함으로서 실세계의 3차원 표현이 가능하며 실세계를 인터넷, PDA 및 핸드폰 등에 3차원으로 표현하는데 필요한 데이터베이스를 제공할 수 있다. 이는 도래하는 유비쿼터스 시대에 필요한 정확하고 정교한 데이터기반을 구성한다.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.8 no.4
• /
• pp.61-70
• /
• 2005

Airborne laser scanning system needs preprocessing which removes some objects such as buildings from the raw DSM data to construct DEM in building area because the laser pulse can't penetrate into the buildings. This study applied the mean filtering method which has various size filter to the DSM data constructed by airborne laser scanning system and decided the optimal filter size as $39{\times}39$ by analyzing the standard deviation change ratio. Also, this study could get the ${\pm}0.065m$ standard error by comparing the optimal filtering DEM and DSM raw data of airborne laser scanning. Therefore, it could know that the mean filtering method, which is presented in this study, is very effective to extract DEM in the urban area which has a low relief.

• Journal of Korean Society for Geospatial Information Science
• /
• v.16 no.4
• /
• pp.101-107
• /
• 2008

Due to increased interest in environmental friendly ecological development and restoration, civil appeals concerning various environmental and landscape problems are continuously being lodged in cases where open-pit limestone mines are situated in places with eminent natural landscape. In this study, with the open-pit limestone mines located in the Baekdu mountain range as a study area, intends to contribute in recognition of various environmental problems and in the promotion of a reasonable restoration plan through high quality geo-spatial information. And it is planning to establish a method for sustained monitoring of the limestone mining by building intelligent national land information of the study area through combining Airborne Laser Scanning and Terrestrial LiDAR based surveying.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2008.10a
• /
• pp.331-332
• /
• 2008

단빔, 멀티빔, 사이드스캔소나 등을 이용하여 해저면의 위치나 형상파악을 하는 방법은 측량시간과 비용이 막대하게 소요되고 해안절벽과 도서지역은 접근이 용이하지 않은 관계로 이러한 측량환경의 단점을 보완하기 위하여 항공기에 레이저 측량장비를 탑재하여 해저면의 수심을 측량할 수 있는 기술이 확산되고 있다. 본 연구에서는 실험지역에 대하여 항공레이저 수심측량을 실시하고 취득된 데이터를 이용하여 해안선을 추출하였다. 해저면 지역에 대하여 단빔 수심측량 데이터와 비교한 결과, 실험지역 A에서는 표준편차가 ${\pm}1.795m$, 실험지역 B에서는 표준편차가 ${\pm}2.251m$로 제시되었다. 또한 SHOALS 데이터와 7개의 암초에 대하여 9개 지점의 암초 수심측량 값과 비교하였으며, 암초 수심측량 값의 측량밀도가 적어 암초의 형상을 3차원으로 재현함에 있어서 한계가 존재하지만 SHOALS 데이터를 이용하여 암초에 대한 형상을 정확하게 3차원으로 표현할 수 있었다. 육지지역에 대한 SHOALS 데이터 검증을 위하여 라이다 데이터와 비교 한 결과, $0.16m{\pm}0.16m$로 나타났으며, 1/1,000 수치지형도와 비교한 결과, $0.51m{\pm}0.26m$로 SHOALS 데이터의 정확성과 신뢰성을 확인할 수 있었다. 본 연구를 통하여 국내에서도 SHOALS 데이터를 이용하여 해안선측량 및 수심측량에 적용할 수 있는 근거를 제시하였으며, 현행 수심측량으로 어려움이 많은 수심이 낮은 천소지역과 접근이 어려운 절벽지역에 효과적으로 적용할 수 있는 기반을 제시하였다.