• Title/Summary/Keyword: Image Edge

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View Variations and Recognition of 2-D Objects (화상에서의 각도 변화를 이용한 3차원 물체 인식)

  • Whangbo, Taeg-Keun
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.11
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    • pp.2840-2848
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    • 1997
  • Recognition of 3D objects using computer vision is complicated by the fact that geometric features vary with view orientation. An important factor in designing recognition algorithms in such situations is understanding the variation of certain critical features. The features selected in this paper are the angles between landmarks in a scene. In a class of polyhedral objects the angles at certain vertices may form a distinct and characteristic alignment of faces. For many other classes of objects it may be possible to identify distinctive spacial arrangements of some readily identifiable landmarks. In this paper given an isotropic view orientation and an orthographic projection the two dimensional joint density function of two angles in a scene is derived. Also the joint density of all defining angles of a polygon in an image is derived. The analytic expressions for the densities are useful in determining statistical decision rules to recognize surfaces and objects. Experiments to evaluate the usefulness of the proposed methods are reported. Results indicate that the method is useful and powerful.

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A Study on the Application and Formation of the Rural Village Model for the Rural Village (Re)development (농촌마을 계획.정비를 위한 농촌마을모델 형성에 관한 연구)

  • Im, Seung-Bin;Jo, Sun-Jae;Park, Chang-Seok
    • Journal of Korean Society of Rural Planning
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    • v.2 no.2
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    • pp.57-66
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    • 1996
  • The purpose of this study is to suggest the rural village model which is able to be applied to the rural village (re)development. The rural village model consists of five sector models land use model, residential unit model, public facilities allocation model, productive space arrangement model, road & green system model. The village model as a spatial structure needs modification/revision through the its application to various sites. The following are suggestions developed in the process of preparing a model for the Korean rural village. First, some indices presented in the land use model need to be further studied as the planning indices before implementing the rural village projects. Second, it is recomended that the image of a rural village needs to be created by developing the residential unit(6 households) as a planning development unit, And various residential unit models need to be suggested. Third, it is desirable to develop the double circulation system and green edge(1 m), and to introduce pedestrian road as much as possible for the amenity of the residential environment, Fourth, being located within walking distance from the existing village, new-introduced site should be developed as a interlinked and opened structure. The rural village model is useful in preparing the spatial structure for the village (re)development, and in finding the best design solution responsive to the conditions of a project site.

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Surface Rendering in Abdominal Aortic Aneurysm by Deformable Model (복부대동맥의 3차원 표면모델링을 위한 가변형 능동모델의 적용)

  • Choi, Seok-Yoon;Kim, Chang-Soo
    • The Journal of the Korea Contents Association
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    • v.9 no.6
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    • pp.266-274
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    • 2009
  • An abdominal aortic aneurysm occurs most commonly in older individuals (between 65 and 75), and more in men and smokers. The most important complication of an abdominal aortic aneurysm is rupture, which is most often a fatal event. An abdominal aortic aneurysm weakens the walls of the blood vessel, leaving it vulnerable to bursting open, or rupturing, and spilling large amounts of blood into the abdominal cavity. surface modeling is very useful to surgery for quantitative analysis of abdominal aortic aneurysm. the 3D representation and surface modeling an abdominal aortic aneurysm structure taken from Multi Detector Computed Tomography. The construction of the 3D model is generally carried out by staking the contours obtained from 2D segmentation of each CT slice, so the quality of the 3D model strongly defends on the precision of segmentation process. In this work we present deformable model algorithm. deformable model is an energy-minimizing spline guided by external constraint force. External force which we call Gradient Vector Flow, is computed as a diffusion of a gradient vectors of gray level or binary edge map derived from the image. Finally, we have used snakes successfully for abdominal aortic aneurysm segmentation the performance of snake was visually and quantitatively validated by experts.

Height Estimation of the Flat-Rooftop Structures using Line-Based Stereo Matching (직선 기반 스테레오 정합을 이용한 평면 지붕 인공지물의 고도 정보 추출)

  • 최성한;엄기문;이쾌희
    • Korean Journal of Remote Sensing
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    • v.11 no.3
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    • pp.61-70
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    • 1995
  • In this paper, the algorithm to extract the height of flat-rooftop structures in stereo aerial image is suggested with an assumption that location, orientation, focal length, and field of view of a camera are known. It can be adapted to stereo aerial or satellite images. For performing feature-based stereo matching, the line segments suitable to describe the shape of general buildings are chosen as the feature. This paper is composed of three categories;the first step is to extract edges of structures with the polygon extraction algorithm which utilizes the edge following method, the second step is to perform the line segment matching with the camera information, and the last step is to calculate the location of each matched line and to estimate heights. The stereo images used in experiments are not real but synthetic ones. The experiment shows good results.

A Study on Machine Learning Algorithm Suitable for Automatic Crack Detection in Wall-Climbing Robot (벽면 이동로봇의 자동 균열검출에 적합한 기계학습 알고리즘에 관한 연구)

  • Park, Jae-Min;Kim, Hyun-Seop;Shin, Dong-Ho;Park, Myeong-Suk;Kim, Sang-Hoon
    • KIPS Transactions on Software and Data Engineering
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    • v.8 no.11
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    • pp.449-456
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    • 2019
  • This paper is a study on the construction of a wall-climbing mobile robot using vacuum suction and wheel-type movement, and a comparison of the performance of an automatic wall crack detection algorithm based on machine learning that is suitable for such an embedded environment. In the embedded system environment, we compared performance by applying recently developed learning methods such as YOLO for object learning, and compared performance with existing edge detection algorithms. Finally, in this study, we selected the optimal machine learning method suitable for the embedded environment and good for extracting the crack features, and compared performance with the existing methods and presented its superiority. In addition, intelligent problem - solving function that transmits the image and location information of the detected crack to the manager device is constructed.

The improved facial expression recognition algorithm for detecting abnormal symptoms in infants and young children (영유아 이상징후 감지를 위한 표정 인식 알고리즘 개선)

  • Kim, Yun-Su;Lee, Su-In;Seok, Jong-Won
    • Journal of IKEEE
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    • v.25 no.3
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    • pp.430-436
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    • 2021
  • The non-contact body temperature measurement system is one of the key factors, which is manage febrile diseases in mass facilities using optical and thermal imaging cameras. Conventional systems can only be used for simple body temperature measurement in the face area, because it is used only a deep learning-based face detection algorithm. So, there is a limit to detecting abnormal symptoms of the infants and young children, who have difficulty expressing their opinions. This paper proposes an improved facial expression recognition algorithm for detecting abnormal symptoms in infants and young children. The proposed method uses an object detection model to detect infants and young children in an image, then It acquires the coordinates of the eyes, nose, and mouth, which are key elements of facial expression recognition. Finally, facial expression recognition is performed by applying a selective sharpening filter based on the obtained coordinates. According to the experimental results, the proposed algorithm improved by 2.52%, 1.12%, and 2.29%, respectively, for the three expressions of neutral, happy, and sad in the UTK dataset.

Quantifications of Intensity-Modulated Radiation Therapy Plan Complexities in Magnetic Resonance Image Guided Radiotherapy Systems

  • Chun, Minsoo;Kwon, Ohyun;Park, Jong Min;Kim, Jung-in
    • Journal of Radiation Protection and Research
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    • v.46 no.2
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    • pp.48-57
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    • 2021
  • Background: In this study, the complexities of step-and-shoot intensity-modulated radiation therapy (IMRT) plans in magnetic resonance-guided radiation therapy systems were evaluated. Materials and Methods: Overall, 194 verification plans from the abdomen, prostate, and breast sites were collected using a 60Co-based ViewRay radiotherapy system (ViewRay Inc., Cleveland, OH, USA). Various plan complexity metrics (PCMs) were calculated for each verification plan, including the modulation complexity score (MCS), plan-averaged beam area (PA), plan-averaged beam irregularity, plan-averaged edge (PE), plan-averaged beam modulation, number of segments, average area among all segments (AA/Seg), and total beam-on time (TBT). The plan deliverability was quantified in terms of gamma passing rates (GPRs) with a 1 mm/2% criterion, and the Pearson correlation coefficients between GPRs and various PCMs were analyzed. Results and Discussion: For the abdomen, prostate, and breast groups, the average GPRs with the 1 mm/2% criterion were 77.8 ± 6.0%, 79.8 ± 4.9%, and 84.7 ± 7.3%; PCMs were 0.263, 0.271, and 0.386; PAs were 15.001, 18.779, and 35.683; PEs were 1.575, 1.444, and 1.028; AA/Segs were 15.37, 19.89, and 36.64; and TBTs were 18.86, 19.33, and 5.91 minutes, respectively. The various PCMs, i.e., MCS, PA, PE, AA/Seg, and TBT, showed statistically significant Pearson correlation coefficients of 0.416, 0.627, -0.541, 0.635, and -0.397, respectively, with GPRs. Conclusion: The area-related metrics exhibited strong correlations with GPRs. Moreover, the AA/Seg metric can be used to estimate the IMRT plan accuracy without beam delivery in the 60Co-based ViewRay radiotherapy system.

The Truth of the Photograph and its Representation of Observer Appeared in the Painting of History (역사그림에 나타난 사진의 진실과 관찰자적 재현)

  • Lee, Kyung-Ryul
    • Cross-Cultural Studies
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    • v.29
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    • pp.25-53
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    • 2012
  • The attitude of observer in the painting of history is to exclude a prejudice and a subjective view of an artist and to introduce a photograph, which is a record of objectivity, in the process of painting. Its ultimate intent is to redescribe the fact of an event's image intactly without any prejudice and to represent the event as a proven evidence that it was. The representation of history based on fact had already been conceived in imagination of renowned artists such as Francisco Goya or $Th{\acute{e}}odore$ $G{\acute{e}}ricault$ even before cameras were invented. What they portrayed was their own truth of reality which is gained through their observation, not a history that have corresponded to political ideologies, for all reliance on a limited tool of representation, painting. Furthermore, history was necessary for 19th century impressionism artists to be represented under proven fact in a neutral perspective excluding all subjective prejudice, not based on the representation with imagination. Edouard Manet in particular reconstited an instant moment on the basis of real proof of photograph without personal prejudice or opinion as if today's photojournalism. The catastrophic series by Andy Warhol and the photographic painting by Gerhard Richter show another role of painting in the realm of art, each of them implying information distortion and abuse by current media and intentional deformation toward history as Manet's painting of history. Today, the representation of an historical event that we experience in the era of the Internet and social networks having a great deal of information already came to be the exclusive property of the cutting edge mass media. Nevertheless, the attitude of observer which is realistic and contemplative in the realm of art is the crucial point in terms of artists' act as ever.

The Effects of Muscle Energy Technique on the Shoulder Complex Range of Motion and Posture Alignment of Female College Students in their Twenties with a Round Shoulder (근에너지기법이 둥근어깨를 가진 20대 여대생의 어깨복합체 가동성과 자세정렬에 미치는 영향)

  • Im, Gyeong-eun;Jeong, Yeon-woo;Seo, Tae-hwa
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.27 no.2
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    • pp.17-25
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    • 2021
  • Background: The purpose of this study is to investigate basic data about the effects of muscle energy technique on the shoulder complex range of motion and posture alignment in the round shoulder posture. Methods: The subjects included 15 women that gave consent to participate in the study voluntarily. They performed the muscle energy technique for 30 minutes twice. The round shoulder posture was measured with a straight edge ruler. The shoulder complex range of motion was measured with the apley scratch test. The forward head posture was measured with ImageJ. The pectoralis minor muscle length was measured with a tape measure. Results: There were statistically significant differences in the round shoulder posture both right and left (p<.05). The experiment group showed statistically significant differences in the pectoralis minor muscle length (p<.05). There were significant differences in the shoulder complex range of motion including flexion, left lateral flexion, right lateral flexion, left side bending, and right side bending (p<.05), but no significant differences were found in extension (p>.05). The forward head posture showed significant differences in CVA changes (p<.05) and no significant differences in CRA changes (p>.05). Conclusion: These findings demonstrate that the muscle energy technique relaxed muscles around the shoulders and increased the shoulder complex range of motion. The technique is also expected to prevent pain in the neck and shoulders and lower injury risk. In conclusion, the muscle energy technique can be applied as an effective intervention for round shoulder posture.

Modified Weighted Filter by Standard Deviation in S&P Noise Environments (S&P 잡음 환경에서 표준편차를 이용한 변형된 가중치 필터)

  • Baek, Ji-Hyeon;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.4
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    • pp.474-480
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    • 2020
  • With the advent of the Fourth Industrial Revolution, many new technologies are being utilized. In particular, video signals are used in various fields. However, when transmitting and receiving video signals, salt and pepper noise and additive white Gaussian noise (AWGN) occur for multiple reasons. Failure to remove such noise when performing image processing can cause problems. Generally, filters such as CWMF, MF, and AMF remove noise. However, these filters perform somewhat poorly in the high-density noise domain and cause smoothing, resulting in slightly lower retention of the edge components. In this paper, we propose an algorithm by effectively eliminating salt and pepper noise using a modified weight filter using standard deviation. In order to prove the noise reduction performance of the proposed algorithm, we compared it with the existing algorithm using PSNR and magnified images.