• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.27 no.6
• /
• pp.669-678
• /
• 2009

Real-time image georeferencing technologies are required to generate spatial information promptly from the image sequences acquired by a multi-sensor system. We thus derive a sequential adjustment algorithm based on the combined adjustment model. By adopting the sequential adjustment model, we develop a sequential AT(Aerial Triangulation) algorithm to georeference image sequences in real-time. The proposed algorithm enables to perform AT rapidly with the minimum computation at the current stage by using the results computed at the previous stage whenever a new image is added. Experiments with simulated data were conducted to verify the effectiveness of the proposed algorithm. The results of the experiments show that the georeferencing of each image took very short time and its accuracy was determined within ${\pm}4cm$ on the ground control points comparing to the results of the existing simultaneous AT.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2006.04a
• /
• pp.345-351
• /
• 2006

습지나 얕은 바다에 존재하는 중금속의 분포를 모델링하는 것은 그 곳의 생태계를 보존하기 위해 꼭 필요한 일이다. 본 연구에서는 GIS(Geographic Information System) 기법 및 위성영상, 실제 대상지역 측량자료를 이용하여 베트남의 동남쪽에 있는 메콩강 삼각주 지역의 중금속 분포를 예측하는 기법을 제안하였다. 이를 위해 중금속의 분포에 영향을 미치는 공간적 요소(Spatial factor)와 구조적 요소(Structural factor)를 통계적으로 처리함으로써 대상지역에 대한 As(arsenic) 오염도를 예측하였다. 또한 중금속 오염되었다고 평가된 지역을 위성영상을 이용하여 표현함으로써 본 연구의 결과를 시각적으로 제시하였다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2008.10a
• /
• pp.13-15
• /
• 2008

LiDAR(Light Detection and Ranging)는 3차원공간정보를 신속하게 구축할 수 있는 최신 측량 기술로써 최근 그 활용도와 중요성이 높아지고 있다. 그러나 LiDAR 관측성과는 시스템 특성상 높은 수직 정확도를 제공하고 있으나 항공사진과 같이 정확한 평면위치를 측정하여 조정할 수 없으므로 상대적으로 낮은 수평 정확도를 가지고 있다. 본 연구에서는 LiDAR 관측에 의한 건물의 벽면 반사파를 이용하여 건물모서리의 평면 좌표(x, y)를 추출하고, 이를 항공삼각측량에 의한 평면좌표와 비교분석하였다. 그 결과 LiDAR의 평면좌표가 항공삼각측량에 의한 평면좌표에 비해 상대적으로 이동되어 있음을 확인할 수 있었다. 따라서, 2차원 좌표변환을 수행하여 LiDAR의 평면좌표를 보정하여 정확도를 향상시킬 수 있었고, 이를 이용하여 향후 LiDAR 관측성과 품질 향상에 도움이 될 것이라 기대한다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 1999.12a
• /
• pp.52-58
• /
• 1999

본 연구에서는 국내의 항공사진측량에서 적용되지 않고 있는 광속조정 Program을 구현하였다. 또한, 구현된 프로그램을 이용하여 과천지역에 대한 측량자료를 처리하였다. GPS를 이용하여 결정한 카메라 노출중심 위치를 이용하여 광속조정에 적용한 결과는 지상기준점수가 감소하여도 정확도는 완만하게 저하되었으나, 지상기준점만을 이용하여 광속조정에 적용한 결과는 지상기준점수가 감소함에 따라 정확도는 급격하게 저하되었다. GPS를 이용하여 결정한 카메라 노출중심 위치를 광속조정에 적용한 결과 블록 가장자리에 배치한 4개의 지상기준점 만으로 공공측량에 적합한 결과를 얻을 수 있었다. 본 연구를 통하여 GPS로 결정한 카메라의 노출중심위치를 항공삼각측량에 적용할 경우 필요한 지상기준점수를 축소함으로써, 비용을 절감할 수 있을 것으로 판단된다.

• Economic and Environmental Geology
• /
• v.48 no.3
• /
• pp.205-212
• /
• 2015

We have verified applicability of UAV(Unmanned Aerial Vehicle) photogrammetry to a mining engineering. The test mine is a smectite mine located at Gyeongju city in Gyeongnam province, Koera. 448 photos over area of $600m{\times}380m$ were taken with overlapped manner using Cannon Mark VI equipped to multicopter DJI S1000, which were processed with AgiSoft Photoscan software to generate orthophoto and DEM model of the study area. photogrammetry data with 10 cm resolution were generated using 6 ground control positions, which were exported to the 3D geological modeling software to make a topographic surface object. Monitoring of amount of ore production and landsliding could be done with less than 1 hours photographing as well as low cost. A direct link between UAV photogrammetry and 3D geological modeling technology might increase productivity of a mine due to appling the topographical surface change immediately according to the mining operation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.36 no.4
• /
• pp.235-243
• /
• 2018

The national geodetic control point is very important as a framework for drafting plans for construction and civil engineering works as well as mapping for various development and utilization plans related to the national land. Since the 1910s, Korea has established and managed the national geodetic control points, the triangulation points and the benchmarks. Currently, these point information is provided through the land information platform. The national geodetic control point has been changed through the process of loss, re-establishment, and re-location by the events and environment of the times. Therefore, it is very important to provide information by linking these past national geodetic control points in time series. In this study, we classified the triangulation points into five groups(Japanese Government General of Korea, YUCCA Project, National Construction Institute, Past Control Point Data Sheet, and Current) by age and then suggests a method to match the same control points in each time period. Finally we also applied the proposed method to Jecheon and analyzed the results.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.12
• /
• pp.2943-2948
• /
• 2015

Run 3D reconstruction using a single camera, based on the information, we are advancing research on driving assistance apparatus or can be informed how to pass the obstacle existing ahead the driver. As a result depth information falls but it is possible to provide information that can pass through an obstacle on the straight. For 3D reconstruction by measuring the internal parameters, it calculates the Fundamental matrix and matching to find the feature points obtained by executing the triangulation on the basis of this. When the through experiments try to confirm the results, the depth information is present error information in the X and Y axes which can determine whether or not to pass through an obstacle has reliability.

• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.71-82
• /
• 2006

This paper propose a realtime tracking algorithm of mobile object in indoor environment. this proposed system selects location data closer to mobile objects in real time that are results of Triangulation method and DCM(Database Correlation Method)method. Also, this system applies adjusted location data selected by using Kalman filter, and in result it improved location accuracy of transfer object. Be studied in existing the Kalman filter have unstable location data until its settlement because of it extracts current values by using the past the information. However, proposed location tracking system don't apply existent Kalman filter to this system and it permits precisional tracking location by uses more effective methods.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.8 no.2
• /
• pp.1-8
• /
• 1990

A regular grid or a triangulated irregular network is generally used as the data structure of digital terrain models. A Regular grid is simple and easy to manipulate, but it can't describe well terrain surface features and requires vast volumes of data. In the meantime, a triangulated irregular network has complex data structure, but it can describe well terrain surface features and can achieve the accuracy suitable to its application with relatively little data. This paper aims at the construction of efficient digital terrain models by the improvment of a triangulated irregular network based on Delaunay triangulation. Regular and irregular data set are sampled from existing contour maps, and the efficiency and the accuracy of the two data structures are compared.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.30 no.2
• /
• pp.173-180
• /
• 2012

The most recent, 80 mega pixels digital camera appeared through the development of digital technology, and nonmetric digital cameras have been using in various field of photogrammetry. In this study, we experimented lens calibration using aerial photographs and ground control points. The aerial photographs were taken a non-metric digital camera which is CMOS(Complementary Metal Oxide Semiconductor) 21.1 mega pixels sensor and 35mm lens at a helicopter. And the ground control points were selected on the 1:1,000 plotting origin data. As a result, we calculated focal length, PPA(Principal Point of Autocollimation) and symmetric radial distortion coefficients from the lens. Also, RMSE(root mean square error) and maximum residual of the ground control points from the aerial triangulation were compared before and after calibration. And we found that the accuracy of the after calibration was improved very significantly.