• Title/Summary/Keyword: Disparity acquisition

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A Study on Stereo Visualization of the X-ray Scanned Image Based on Volume Reconstruction (볼륨기반 X-선 스캔영상의 3차원 형상화 연구)

  • Lee, Nam-Ho;Park, Soon-Yong;Hwang, Young-Gwan;Park, Jong-Won;Lim, Yong-Gon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.7
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    • pp.1583-1590
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    • 2011
  • As the existing radiation scanning systems use 2-dimensional radiation scanned images, the low accuracy has been pointed out as a problem of it. This research analyzes the applicability of the stereo image processing technique to X-ray scanned images. Two 2-dimensional radiation images which have different disparity values are acquired from a newly designed stereo image acquisition system which has one additional line sensor to the conventional system. Using a matching algorithm the 3D reconstruction process which find the correspondence between the images is progressed. As the radiation image is just a density information of the scanned object, the direct application of the general stereo image processing techniques to it is inefficient. To overcome this limitation of a stereo image processing in radiation area, we reconstruct 3-D shapes of the edges of the objects. Also, we proposed a new volume based 3D reconstruction algorithm. Experimental results show the proposed new volume based reconstruction technique can provide more efficient visualization for cargo inspection. The proposed technique can be used for such objects which CT or MRI cannot inspect due to restricted scan environment.

Simulation of Radiation Imaging based on the Scanning of Pin-hole Stereo Vision Sensors (핀홀 스테레오 비전 센서의 공간 스캔을 통한 방사선의 영상화 시뮬레이션)

  • Park, Soon-Yong;Baek, Seung-Hae;Choi, Chang-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1671-1680
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    • 2014
  • There are always much concern about the leakage of radiation materials in the event of dismantle or unexpected accident of nuclear power plant. In order to remove the leakage of radiation materials, appropriate dispersion detection techniques for radiation materials are necessary. However, because direct handling of radiation materials is highly restricted and risky, developing radiation-related techniques needs computer simulation in advance to evaluate the feasibility. In this paper, we propose a radiation imaging technique which can acquire 3D dispersion information of radiation materials and tested by simulation. Using two virtual 1D radiation sensors, we obtain stereo radiation images and acquire the 3D depth to virtual radiation materials using stereo disparity. For point and plane type virtual radiation materials, the possibility of the acquisition of stereo radiation image and 3D information are simulated.

The Study of automated inspection technology using a three-dimensional reconstruction of stereo X-ray image based dual-sensor Environment (Dual-Sensor 기반 스테레오 X-선 영상의 3차원 형상복원기술을 이용한 검색 자동화를 위한 연구)

  • Hwang, Young-Gwan;Lee, Nam-Ho;Kim, Jong-Ryul
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.695-698
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    • 2014
  • As most the scanning systems developed until now provide radiation scan plane images of the inspected objects, there has been a limitation in judging exactly the shape of the objects inside a logistics container exactly with only 2-D radiation image information. Two 2-dimensional radiation images which have different disparity values are acquired from a newly designed stereo image acquisition system which has one additional line sensor to the conventional system. Using a matching algorithm the 3D reconstruction process which find the correspondence between the images is progressed. In this paper, we proposed a new volume based 3D reconstruction algorithm and experimental results show the proposed new volume based reconstruction technique can provide more efficient visualization for cargo inspection. The proposed technique can be used for the development of the high speed and more efficient non-destructive auto inspection system.

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Development of an Image Processing Algorithm for Paprika Recognition and Coordinate Information Acquisition using Stereo Vision (스테레오 영상을 이용한 파프리카 인식 및 좌표 정보 획득 영상처리 알고리즘 개발)

  • Hwa, Ji-Ho;Song, Eui-Han;Lee, Min-Young;Lee, Bong-Ki;Lee, Dae-Weon
    • Journal of Bio-Environment Control
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    • v.24 no.3
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    • pp.210-216
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    • 2015
  • Purpose of this study was a development of an image processing algorithm to recognize paprika and acquire it's 3D coordinates from stereo images to precisely control an end-effector of a paprika auto harvester. First, H and S threshold was set using HSI histogram analyze for extracting ROI(region of interest) from raw paprika cultivation images. Next, fundamental matrix of a stereo camera system was calculated to process matching between extracted ROI of corresponding images. Epipolar lines were acquired using F matrix, and $11{\times}11$ mask was used to compare pixels on the line. Distance between extracted corresponding points were calibrated using 3D coordinates of a calibration board. Non linear regression analyze was used to prove relation between each pixel disparity of corresponding points and depth(Z). Finally, the program could calculate horizontal(X), vertical(Y) directional coordinates using stereo camera's geometry. Horizontal directional coordinate's average error was 5.3mm, vertical was 18.8mm, depth was 5.4mm. Most of the error was occurred at 400~450mm of depth and distorted regions of image.

Analysis of Elementary School Teachers' Attitude Toward School Food Service Management and Effect (학교급식의 관리와 효과에 대한 초등교사들의 태도 분석)

  • Kim, Hak-Hyun
    • The Journal of Korean Society for School & Community Health Education
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    • v.1 no.1
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    • pp.61-82
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    • 2000
  • The purpose of this study was to find out the general problems of school food service and to explore a way to improve it, by examining elementary school teacher's consciousness and attitude toward it that gave a big impact on children's development of food habit. For attaining the purpose, the following research questions were posed : 1) What's elementary school teacher attitude toward school food service management? 2) What's elementary school teacher attitude toward school food service effect on children? 3) What's elementary school teacher opinion about how to develop school food service? The subjects of study were 328 male or female teachers who served at elementary school in urban and rural area, including eup, myon, or farming and fishing villages, Kyonggi province. A questionnaire survey was conducted over them. The conclusions were as follows: 1) Teacher Attitude Toward School Food Service Management Concerning food service place, the subjects were more satisfied at food service room(73.3%) than at classroom(23.0%). They responded that food service room was more effective, than classroom, for food transportation, distribution and post-arrangement. Their satisfaction at food service place was significantly different. The older teachers considered personnel management and cooking room's sanitary management to be more efficient, and their age made a significant difference to their consciousness of these things. Many teachers(63.1%) thought the measures to prevent and manage group food poisoning were relatively efficient. The male teachers expressed more affirmative view on the efficiency of school food expense management and menu preparation than female teachers, and there was a significant disparity between male and female teachers. 2) Elementary School Food Service Effect School food service was thought to be very effective for physical growth(74.1%) and physical strength improvement(70.1%). Teachers at smaller school revealed more affirmative response toward school food service effect on correcting an unbalanced diet, and older teachers considered its effect on nutrition knowledge acquisition and learning outcome to be more great. Teachers at larger school put less value on its effect on table manners, and school size produced a significant difference. The number of teachers who thought school food service generally raised parent concern and support for school(36.6%) was a little more than that of teachers who didn't think so(15.2%). And the number of teachers who didn't consider its effect on improving parent food life to be good(29.3%) was slightly more than that of teachers who did. 3) School Food Service Reform Measure What's most urgently needed for better school food service management appeared to be an expansion of facilities concerned, followed by more effective food distribution and transport, cooking room's better sanitary management, more successful food poisoning prevention and management, more effective food expense management, and an increase of food service personnel in the order named. The most effective means of school food service education was found to be a creation of link system to family, followed by a development of school food service education program, a development of teaching materials, an insertion of school food service in curriculum, and teacher education in the order named.

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Stereo Image-based 3D Modelling Algorithm through Efficient Extraction of Depth Feature (효율적인 깊이 특징 추출을 이용한 스테레오 영상 기반의 3차원 모델링 기법)

  • Ha, Young-Su;Lee, Heng-Suk;Han, Kyu-Phil
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.10
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    • pp.520-529
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    • 2005
  • A feature-based 3D modeling algorithm is presented in this paper. Since conventional methods use depth-based techniques, they need much time for the image matching to extract depth information. Even feature-based methods have less computation load than that of depth-based ones, the calculation of modeling error about whole pixels within a triangle is needed in feature-based algorithms. It also increase the computation time. Therefore, the proposed algorithm consists of three phases, which are an initial 3D model generation, model evaluation, and model refinement phases, in order to acquire an efficient 3D model. Intensity gradients and incremental Delaunay triangulation are used in the Initial model generation. In this phase, a morphological edge operator is adopted for a fast edge filtering, and the incremental Delaunay triangulation is modified to decrease the computation time by avoiding the calculation errors of whole pixels and selecting a vertex at the near of the centroid within the previous triangle. After the model generation, sparse vertices are matched, then the faces are evaluated with the size, approximation error, and disparity fluctuation of the face in evaluation stage. Thereafter, the faces which have a large error are selectively refined into smaller faces. Experimental results showed that the proposed algorithm could acquire an adaptive model with less modeling errors for both smooth and abrupt areas and could remarkably reduce the model acquisition time.

Intermediate View Image and its Digital Hologram Generation for an Virtual Arbitrary View-Point Hologram Service (임의의 가상시점 홀로그램 서비스를 위한 중간시점 영상 및 디지털 홀로그램 생성)

  • Seo, Young-Ho;Lee, Yoon-Hyuk;Koo, Ja-Myung;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.1
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    • pp.15-31
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    • 2013
  • This paper proposes an intermediate image generation method for the viewer's view point by tracking the viewer's face, which is converted to a digital hologram. Its purpose is to increase the viewing angle of a digital hologram, which is gathering higher and higher interest these days. The method assumes that the image information for the leftmost and the rightmost view points within the viewing angle to be controlled are given. It uses a stereo-matching method between the leftmost and the rightmost depth images to obtain the pseudo-disparity increment per depth value. With this increment, the positional informations from both the leftmost view point and the rightmost view point are generated, which are blended to get the information at the wanted intermediate viewpoint. The occurrable dis-occlusion region in this case is defined and a inpainting method is proposed. The results from implementing and experimenting this method showed that the average image qualities of the generated depth and RGB image were 33.83[dB] and 29.5[dB], respectively, and the average execution time was 250[ms] per frame. Also, we propose a prototype system to service digital hologram interactively to the viewer by using the proposed intermediate view generation method. It includes the operations of data acquisition for the leftmost and the rightmost viewpoints, camera calibration and image rectification, intermediate view image generation, computer-generated hologram (CGH) generation, and reconstruction of the hologram image. This system is implemented in the LabView(R) environments, in which CGH generation and hologram image reconstruction are implemented with GPGPUs, while others are implemented in software. The implemented system showed the execution speed to process about 5 frames per second.

An Examination into the Illegal Trade of Cultural Properties (문화재(文化財)의 국제적 불법 거래(不法 去來)에 관한 고찰)

  • Cho, Boo-Keun
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.371-405
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    • 2004
  • International circulation of cultural assets involves numerous countries thereby making an approach based on international law essential to resolving this problem. Since the end of the $2^{nd}$ World War, as the value of cultural assets evolved from material value to moral and ethical values, with emphasis on establishing national identities, newly independent nations and former colonial states took issue with ownership of cultural assets which led to the need for international cooperation and statutory provisions for the return of cultural assets. UNESCO's 1954 "Convention for the Protection of Cultural Property in the Event of Armed Conflict" as preparatory measures for the protection of cultural assets, the 1970 "Convention on the Means of Prohibiting and Preventing the Illicit Import and Transfer of Ownership of Cultural Property" to regulate transfer of cultural assets, and the 1995 "Unidroit Convention on Stolen or Illegally Exported Cultural Objects" which required the return of illegally acquired cultural property are examples of international agreements established on illegal transfers of cultural assets. In addition, the UN agency UNESCO established the Division of Cultural Heritage to oversee cultural assets related matters, and the UN since its 1973 resolution 3187, has continued to demonstrate interest in protection of cultural assets. The resolution 3187 affirms the return of cultural assets to the country of origin, advises on preventing illegal transfers of works of art and cultural assets, advises cataloguing cultural assets within the respective countries and, conclusively, recommends becoming a member of UNESCO, composing a forum for international cooperation. Differences in defining cultural assets pose a limitation on international agreements. While the 1954 Convention states that cultural assets are not limited to movable property and includes immovable property, the 1970 Convention's objective of 'Prohibiting and preventing the illicit import, export and transfer of ownership of cultural property' effectively limits the subject to tangible movable cultural property. The 1995 Convention also has tangible movable cultural property as its subject. On this point, the two conventions demonstrate distinction from the 1954 Convention and the 1972 Convention that focuses on immovable cultural property and natural property. The disparity in defining cultural property is due to the object and purpose of the convention and does not reflect an inherent divergence. In the case of Korea, beginning with the 1866 French invasion, 36 years of Japanese colonial rule, military rule and period of economic development caused outflow of numerous cultural assets to foreign countries. Of course, it is neither possible nor necessary to have all of these cultural properties returned, but among those that have significant value in establishing cultural and historical identity or those that have been taken symbolically as a demonstration of occupational rule can cause issues in their return. In these cases, the 1954 Convention and the ratification of the first legislation must be actively considered. In the return of cultural property, if the illicit acquisition is the core issue, it is a simple matter of following the international accords, while if it rises to the level of diplomatic discussions, it will become a political issue. In that case, the country requesting the return must convince the counterpart country. Realizing a response to the earnest need for preventing illicit trading of cultural assets will require extensive national and civic societal efforts in the East Asian area to overcome its current deficiencies. The most effective way to prevent illicit trading of cultural property is rapid circulation of information between Interpol member countries, which will require development of an internet based communication system as well as more effective deployment of legislation to prevent trading of illicitly acquired cultural property, subscription to international conventions and cataloguing collections.