• Title/Summary/Keyword: 고밀도 DSM

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High Quality Ortho-image Production Using the High Resolution DMCII Aerial Image (고해상도 DMCII 항공영상을 이용한 고품질 정사영상 제작)

  • Kim, Jong Nam;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.1
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    • pp.11-21
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    • 2015
  • An Ortho-image is the production of removed geometrical displacement, which is generated the aerial image distortion and the relief displacement, etc., using the DSM (Digital Surface Model). Accordingly, the resolution of raw image and the accuracy of DSM will has significant impacts on the ortho-image accuracy. Since the latest DMCII250 aerial camera delivers the high resolution images with five centimeters Ground Sampling Distance(GSD), it expects to generate the high density point clouds and the high quality ortho-images. Therefore, this research has planned for reviewing the potentiality and accuracy of high quality ortho-image production. Following to proceed the research, DSM has been produced through the high density point cloud extracted from DMCII250 aerial image to supply of high density DSM by creation of ortho-image. The research results has been identified that images with the DSM brought out higher degrees in positional accuracy and quality of ortho-image, compared with the ortho-image, produced from the existing digital terrain map or DSM data.

SGM Performance Improvement of Stereo Satellite Image with Classified Image and Edge Image (분류영상과 에지영상을 이용한 입체 위성영상의 SGM 성능개선)

  • Lee, Hyoseong;Park, Byungwook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.38 no.6
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    • pp.655-661
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    • 2020
  • SGM (Semi Global Matching) can be used to find all the conjugate points between stereo images. Therefore, it enables high-density DSM (Digital Surface Model) production from high-resolution satellite images. However, water, shadows, and occlusion areas cause mismatching of the surrounding points in this method. Particularly, in buildings with large-parallax and elongated-shapes such as a Korean style apartment, it is difficult to reconstruct the 3D building even if the SGM method is applied to a high-resolution 50cm satellite image. This study proposed and performed the SGM technique with a classified image and an edge image from the IKONOS-2 satellite stereo-image with a 1m resolution to produce DSM. It was compared with the DSMs from the general SGM and the high-density ABM (Area Based Matching) matching of ERDAS software. The results of the apartment DSM by the proposed method were the best in the test area. As a result, despite the image having a resolution of 1m, the outline of the building DSM could be expressed more clearly than the existing method.

Study on Applicability of Unmanned Aerial Vehicle for Water Disaster Management (수재해 관리를 위한 무인항공기 적용성 검토)

  • Lee, Hyun Seok;Jung, Kwan Sue;Yu, Wan SiK;Kim, Young Kyu
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.249-249
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    • 2016
  • 무인항공기(UAV)는 군사적 목적으로 개발되었지만, 최근 다양한 분야에서 활용되고 있다. 수자원 관리를 위해서도 시대적 흐름에 따라 드론과 관련된 많은 연구가 진행되고 있다. 이수임 등(2015)은 UAV영상을 활용한 수변구조물의 DSM 생성 및 정확도 연구를 통해 지상 LIDAR와 같은 수준의 DSM 및 더욱 정확한 GCP 취득의 필요성을 제시했다. 이용창(2015)은 회전익 UAS 영상기반 고밀도 측점자료의 위치 정확도를 평가하였다. 이인수 등(2013)은 초경량 고정익무인항공기 사진측량기법의 정사영상 정확도 평가를 수행하였다. 또한 김민규 등(2010)은 풍수해 모니터링을 위한 UAV 적용성 분석을 실시하였고, 김홍래 등(2014)은 UAV를 활용한 감시정보정찰 임무분석 및 설계도구 개발을 위한 연구를 수행하였다. 상기와 같이 수자원 분야 활용을 위한 많은 연구가 보고 되고 있으나, 아직까지 드론 활용의 대부분은 항공영상 취득 및 분석기술 개발에 집중되어 있다. 본 연구에서는 무인항공기를 수재해 감시 및 관리 기술에 적용하기 위해 수행되었다. 수재해 감시 및 관리를 위한 방법으로 NIR(Near Infrared) 센서를 부착한 '재해관리용 드론'을 개발하고 현장실험을 수행하였다. 실험결과 NIR센서를 탑재한 드론은 수재해 관리에 매우 유용하게 활용될 수 있을 것으로 판단되었다.

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Serum Lipid Profiles after Abstinence in Korean Male Patients With Alcohol Dependence (남성 알코올 의존 환자들에서 금주 치료 후의 혈청 지질 농도 변화)

  • Lee, Seoung-Ho;Park, Woong-Sub
    • Korean Journal of Biological Psychiatry
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    • v.15 no.1
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    • pp.23-28
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    • 2008
  • Objectives : The treatment of alcohol dependence requires maintaining abstinence. However, some previous studies have suggested that the abstinence may increase the cardiovascular risk in patients with alcohol dependence. The aim of the present study was to examine the effect of alcohol abstinence on lipid profile in Korean male patients with alcohol dependence. Methods : Twenty-eight male patients with alcohol dependence were recruited from a psychiatric unit located at Gangneung Dongin Hospital. Lipid profiles of the patients were compared before and after a month of alcohol abstinence. Results : After abstinence of 1 month, high-density lipoprotein(HDL) cholesterol and triglyceride(TG) level was significantly decreased(p=0.000; p=0.0086, respectively). Low-density lipoprotein(LDL) cholesterol level showed a tendency to increase(p=0.066). Total cholesterol level also showed a tendency to decrease(p=0.074). Conclusions : These results show that acute abstinence of alcohol might paradoxically aggravate dyslipidemia in patients with alcohol dependence. Thus, this study shows that more concern associated with cardiovascular risk is needed during short-term abstinence period.

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