• Journal of Korea Water Resources Association
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• v.39 no.11 s.172
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• pp.969-976
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• 2006

The purpose of this study is to trace the flood inundation area around rural small stream by using RADARSAT image because it has the ability of acquiring data during storm period irrespective of rain and cloud. For the storm August 9, 1998 in the Anseong-cheon watershed, three RADARSAT images before, just after and after the storm were used. After ortho-rectification using 5 m DEM, two methods of RGB composition and ratio were tried and found the inundated area in the tributary stream, the Seonghwan-cheon and the Hakjeong-cheon. The inundated area had occurred at the joint area of two streams, thus the floodwater overflowed bounding discharge capacity of the stream. The progression of damage areas were stopped by the local road and farm road along the paddy. The result can be used to acquire the flood inundation data scattered as a small scale in rural area.

• Journal of KIISE
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• v.44 no.9
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• pp.932-945
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• 2017

In this paper, a new hardware and software architecture for a stereo vision processing system including rectification, disparity estimation, and visualization was developed. The developed method, named LArge scale stereo matching method using Support Point Interpolation (LASPI), shows excellence in real-time processing for obtaining dense disparity maps from high quality image regions that contain high density support points. In the real-time processing of high definition (HD) images, LASPI does not degrade the quality level of disparity maps compared to existing stereo-matching methods such as Efficient LArge-scale Stereo matching (ELAS). LASPI has been designed to meet a high frame-rate, accurate distance resolution performance, and a low resource usage even in a limited resource environment. These characteristics enable LASPI to be deployed to safety-critical applications such as an obstacle recognition system and distance detection system for autonomous vehicles. A Field Programmable Gate Array (FPGA) for the LASPI algorithm has been implemented in order to support parallel processing and 4-stage pipelining. From various experiments, it was verified that the developed FPGA system (Xilinx Virtex-7 FPGA, 148.5MHz Clock) is capable of processing 30 HD ($1280{\times}720pixels$) frames per second in real-time while it generates disparity maps that are applicable to real vehicles.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.2
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• pp.99-109
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• 2013

In this paper, we propose a new system which captures real depth and color information from natural scene and implemented it. Based on it, we produced stereo and multiview images for 3-dimensional stereoscopic contents and introduced the production of a digital hologram which is considered to the next-generation image. The system consists of both a camera system for capturing images which correspond to RGB and depth images and softwares (SWs) for various image processings which consist of pre-processing such as rectification and calibration, 3D warping, and computer generated hologram (CGH). The camera system use a vertical rig with two paris of depth and RGB camera and a specially manufactured cold mirror which has the different transmittance according to wavelength for obtaining images with the same view point. The wavelength of our mirror is about 850nm. Each algorithm was implemented using C and C++ and the implemented system can be operated in real-time.

• Journal of radiological science and technology
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• v.23 no.1
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• pp.55-61
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• 2000

This report was the results of an investigation based on the status of the mammography in the 45 medical facilities in the areas of Seoul and Kyong-Gi Do. In regard to mammography we were able to understand the rectification method of the generator, the functions, the radiographic techniques, the patient exposure dose, etc. Recently, the occurrence of breast cancer has rapidly increased and has lead to increased interest in the early discovery of breast cancer. However, mammography has not kept up with the publics interests and its demand. The main problem is thought to be a wide great difference in the quality of the facilities, especially in the techniques of radiograpic and the capabilities of the generator, which would have a major effect on the grade management of the image quality. In order to be ready and keep up with the high rate of increase of breast cancer, the standardization of mammography and the grade management is urgently required as a solution to the problems in the increase of image qualify and the decrease of dose. It is regarded that the basic guide of the techniques of photography in the mammography, which is being used in all developed countries due to the influence of the USA, should be presented, especially in Korea, and for this, more active and enthusiastic education and enlightenment should be needed.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.417-422
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• 2003

The KOMPSAT-2 MSC(Multi-Spectral Camera), with high spatial resolution, is currently under development and will be launched in the end of 2004. A sensor model relates a 3-D ground position to the corresponding 2-D image position and describes the imaging geometry that is necessary to reconstruct the physical imaging process. The Rational Function Model (RFM) has been considered as a generic sensor model. form. The RFM is technically applicable to all types of sensors such as frame, pushbroom, whiskbroom and SAR etc. With the increasing availability of the new generation imaging sensors, accurate and fast rectification of digital imagery using a generic sensor model becomes of great interest to the user community. This paper describes the procedure to generation of the RPC (Rational Polynomial Coefficients) for KOMPSAT-2 MSC.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.2
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• pp.127-138
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• 2012

In this paper, we propose a real-time virtual re-convergence hardware platform especially to reduce the visual fatigue caused by stereoscopy. Our unique idea to reduce visual fatigue is to utilize the virtual re-convergence based on the optimized disparity-map that contains more depth information in the negative disparity area than in the positive area. Our virtual re-convergence hardware platform, which consists of image rectification, disparity estimation, depth post-processing, and virtual view control, is realized in real time with 60 fps on a single Xilinx Virtex-5 FPGA chip.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.114-115
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• 2012

In this paper, we improve pre-processing method using markers and propose accurate lattice extraction of elemental image array using minimal markers to correct distortion. We propose a method that almost equal performance of existing method and be more simple calculation. For our method, we did computational experiments and compared with reconstructed images.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.300-305
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• 2005

To trace the flood inundation area around rural small stream, RADARSAT image was applied because it has the ability of acquiring data during storm period irrespective of rain and cloud. For the storm of 9 August, 1998 in Anseong-cheon watershed, three temporal RADARSAT images before, just after and after the storm were used. After ortho-rectification using 5 m DEM, two methods of RGB composition and ratio were tried and found the inundated area in the tributary stream, Seonghwan-cheon and Hakseong-cheon. The inundated area had occurred at the joint area of two streams, thus the floodwater overflowed bounding discharge capacity of the stream. The progression of damage areas were stopped by the local road and farm road along the paddy.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.1424-1427
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• 2015

본 논문에서는 일반적인 동일 기종의 카메라를 사용한 스테레오 카메라 시스템이 아닌, 서로 다른 화각 및 해상도를 가진 이기종 카메라를 이용하여 스테레오 카메라를 설계한다. 본 논문에서 설계하는 스테레오 카메라는 카메라의 수평오차 및 화각, 해상도가 다르다. 따라서 해당 스테레오 카메라를 통해 송출되는 1:1 매칭 되지 않는 영상을 본 논문에서 제시한 코너점 좌표와 기하학변환 방법으로 교정하고 매칭되는 영역을 잘라내는 조정의 과정을 제안한다. 해당 교정 및 조정에는 컴퓨터 비전 라이브러리인 OpenCV를 이용하고 사용자에게 볼 수 있는 프로그램을 MFC를 이용하여 제작한다. 해당 시스템을 통해 교정 및 조정된 영상은 최소한의 픽셀 오차율을 보여 동일한 영역의 감시활동에 효과적임을 보여준다.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.2
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• pp.35-45
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• 2010

The objective of this study is to verify the positional accuracy by performing the orthometric corrections on the high resolution satellite images and to analyze the band correlation between the high resolution images corrected with orthometric correction. The objectives also included an analysis on the correlation of NDVI. For the orthometric correction of images from KOMPSAT2 and IKONOS, systematic errors were removed in use of RPC data, and non-planar distortions were corrected with GPS surveying data. Also, by preempting the image points at the same positions within ortho images, a comparison was performed on positional accuracies between image points of each image and GPS surveying points. The comparison was also made on the positional accuracies of image points. between the images. For correlation of band and correlation of NDVI, the descriptive statistics of DN values were acquired for respective bands by adding the Quickbird images and Aerial Photographs undergone through orthometric correction at the time of purchase. As result, from a comparison on positional accuracies of Orthoimages from KOMPSAT2 and Ortho Images of IKONOS was made. From the comparison the distance between the image points within each image and GPS surveying points was identified as 3.41m for KOMPSAT2 and as 1.45m for IKONOS, presenting a difference of 1.96m. Whereas, RMSE between image points was identified as 1.88m. The level of correlation was measured by using Quickbird, KOMPSAT2, IKONOS and Aerial Photographs between inter-image bands and NDVI, showing that there were high levels of correlation between Quickbird and IKONOS identified from all bands as well as from NDVI, except a high level of correlation that was identified between the Aerial Photographs and KOMPSAT2 from Band 2. Low levels of correlation were also identified between Quickbird and Aerial Photographs from Band 1. and between KOMPSAT2 and IKONOS from Band 2 and Band 4, whereas, KOMPSAT2 showed low correlations with Aerial Photographs from Band 3. For NDVI, KOMPSAT2 showed low level of correlations with both of QuickBird and IKONOS.