• 제목/요약/키워드: Edge area

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A Study of Edge Detection for Auto Focus of Infrared Camera

  • Park, Hee-Duk
    • 한국컴퓨터정보학회논문지
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    • 제23권1호
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    • pp.25-32
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    • 2018
  • In this paper, we propose an edge detection algorithm for auto focus of infrared camera. We designed and implemented the edge detection of infrared image by using a spatial filter on FPGA. The infrared camera should be designed to minimize the image processing time and usage of hardware resource because these days surveillance systems should have the fast response and be low size, weight and power. we applied the $3{\times}3$ mask filter which has an advantage of minimizing the usage of memory and the propagation delay to process filtering. When we applied Laplacian filter to extract contour data from an image, not only edge components but also noise components of the image were extracted by the filter. These noise components make it difficult to determine the focus state. Also a bad pixel of infrared detector causes a problem in detecting the edge components. So we propose an adaptive edge detection filter that is a method to extract only edge components except noise components of an image by analyzing a variance of pixel data in $3{\times}3$ memory area. And we can detect the bad pixel and replace it with neighboring normal pixel value when we store a pixel in $3{\times}3$ memory area for filtering calculation. The experimental result proves that the proposed method is effective to implement the edge detection for auto focus in infrared camera.

컬러와 에지정보를 결합한 조명변화에 강인한 얼굴영역 검출방법 (A New Face Detection Method using Combined Features of Color and Edge under the illumination Variance)

  • 지은미;윤호섭;이상호
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제29권11호
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    • pp.809-817
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    • 2002
  • 본 논문은 온라인 얼굴 인식에서 전처리에 해당하는 얼굴 검출방법을 다룬다. 기존의 얼굴 검출 방법에서 에지 정보만을 이용한 얼굴 검출 방법과 컬러 정보를 이용한 얼굴 검출 방법의 단점을 상호 보완하기 위해 본 연구에서는 에지 정보와 컬러 정보를 결합한 얼굴 검출 방법 및 중심 영역 컬러 샘플링을 이용한 얼굴 검출방법을 개발하였다. 즉, 사람의 얼굴 영역이 비슷한 컬러를 가진 배경 영역과 결합(Merge)되는 것을 막기 위해 먼저 적응형 에지 검출 알고리즘을 수행하여 배경과 얼굴 영역을 각각의 고립 영역으로 분할한다. 제안된 적응형 소벨(Sobel) 에지 검출기는 배경 영역과 얼굴 영역의 경계에서 항상 에지가 발생할 수 있도록 에지가 많이 검출되고 입력 영상의 밝기 변화에 강인하다. 이로 인해 얼굴 영역이 하나의 영역이 아닌 여러 영역으로 분할되어 나타날 수 있으므로, 각 영역들의 컬러 정보를 이용해 병합한 후, 최종 얼굴 영역을 MBR(minimum bounding rectangle) 형태로 검출하였다. 이때 병합된 최종 얼굴 영역 후보가 너무 크거나 혹은 너무 작으면, 중심 영역 샘플링 방법을 이용해 다시 얼굴 영역을 검출한다. 총 2100장의 얼굴 영상 데이터베이스를 통해 실험한 결과 본 연구에서 제안한 방법을 사용해 96.3%의 높은 얼굴 영역 검출 성공률을 얻을 수 있었다.

Z map을 이용한 임의의 절삭영역에서 볼엔드밀의 절삭력예측 (Cutting force prediction in the ball-end milling process of barious cutting area using Z-map)

  • 김규만;조필주;김병희;주종남
    • 한국정밀공학회지
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    • 제14권3호
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    • pp.57-65
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    • 1997
  • In this study, a cutting force in the Ball-end milling process is calculated using Z-map. Z-map can describe any type of cutting area resulting from the previous cutting geometry and cutting condition. Cutting edge of a ball-end mill is divided into infinitesimal cutting edge elements and the position of the ele- ment is projected to the cutter plane normal to the Z axis. Also the cutting area in the cutter plane is obtained by using the Z-map. Comparing this projected position with cutting area, it can be determined whether it engages in the cutting. The cutting force can be calculated by numerical integration of cutting force acting on the engaged cutting edge elements. A series of experiments such as contouring and upward/downward ramp cutting was performed to verify the calculated cutting force.

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패치크기, 연결성, 가장자리를 고려한 보전가치평가 (Conservation Value Assessment by Considering Patch Size, Connectivity and Edge)

  • 이동근;김은영;오규식
    • 한국환경복원기술학회지
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    • 제8권5호
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    • pp.56-67
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    • 2005
  • Rapid and reckless economical development is causing nationwide deforestation; more and more forest is being developed to be used as a base for economic advancement. While benefiting the national economy, this destruction of forest is creating a serious problem in the National Land Plan. To solve this problem, it is imperative to understand the current condition of damaged forest and make an environment-friendly plan. This paper explains the principles of spatial plan and sets the criteria for the plan, such as patch size, connectivity, and edge of the Landscape Ecology. The paper assesses the conservational value of area that are currently being developed or planned to be developed to figure out the current environmental situation. This conservational value was verified by the field survey. The result of assessment appears that the patch size of the major mountains in site is over 1,000ha and edge is located widely beside roads. The area of the high connectivity is located agriculture area in valley or narrow roads. The research shows that the patch size is related to biodiversity the larger the patch size, the more populated the species are. The research also reveals the conservational value indicated by degree of connection to forest, difference in the structure of vegetation between core area and edge area, and effects of surrounding environment. In further study, we will assess other criteria of conservation value, such as patch shape and fragmentation to the Landscape Ecology, and apply those criteria in biological aspects of the spatial plan.

경계선 및 영역 정보를 이용한 스테레오 정합 (Stereo Matching Based on Edge and Area Information)

  • 한규필;김용석;하경훈;하영호
    • 전자공학회논문지B
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    • 제32B권12호
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    • pp.1591-1602
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    • 1995
  • A hybrid approach which includes edge- and region-based methods is considered. The modified non-linear Laplacian(MNL) filter is used for feature extraction. The matching algorithm has three steps which are edge, signed region, and residual region matching. At first, the edge points are matched using the sign and direction of edges. Then, the disparity is propagated from edge to inside region. A variable window is used to consider the local method which give accurate matched points and area-based method which can obtain full-resolution disparity map. In addition, a new relaxation algorithm for considering matching possibility derived from normalized error and regional continuity constraint is proposed to reduce the mismatched points. By the result of simulation for various images, this algorithm is insensitive to noise and gives full- resolution disparity map.

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Model Cut-edge Formed on Zinc Coated Steels by Laser Machining and Its Corrosion Behavior

  • Sakairi, Masatoshi;Kageyama, Akihiro;Kikuhchi, Tatsuya
    • Corrosion Science and Technology
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    • 제9권1호
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    • pp.29-33
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    • 2010
  • Laser machining technique, which is used focusing pulse YAG laser beam irradiation was applied to form area ratio controlled model cut-edge on pre painted Zn coated steels. A corrosion behavior of formed model cut-edge was investigated by rest potential measurement in 1 mol $m^{-3}$ NaCl with and without 0.5 kmol $m^{-3}$ $H_3BO_4$/0.05kmol$m^{-3}$ $Na_2B_4O_7$. The rest potential showed almost constant value with fluctuations. The amplitude of fluctuations increased with exposed area of steel surface. White corrosion products of zinc oxide and simonkollite was formed after the experiments at the formed model cut-edge.

Error Concealment Using Intra-Mode Information Included in H.264/AVC-Coded Bitstream

  • Kim, Dong-Hyung;Jeong, Se-Yoon;Choi, Jin-Soo;Jeon, Gwang-Gil;Kim, Seung-Jong;Jeong, Je-Chang
    • ETRI Journal
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    • 제30권4호
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    • pp.506-515
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    • 2008
  • The H.264/AVC standard has adopted new coding tools such as intra-prediction, variable block size, motion estimation with quarter-pixel-accuracy, loop filter, and so on. The adoption of these tools enables an H.264/AVC-coded bitstream to have more information than was possible with previous standards. In this paper, we propose an effective spatial error concealment method with low complexity in H.264/AVC intra-frame. From information included in an H.264/AVC-coded bitstream, we use prediction modes of intra-blocks to recover a damaged block. This is because the prediction direction in each prediction mode is highly correlated to the edge direction. We first estimate the edge direction of a damaged block using the prediction modes of the intra-blocks adjacent to a damaged block and classify the area inside the damaged block into edge and flat areas. Our method then recovers pixel values in the edge area using edge-directed interpolation, and recovers pixel values in the flat area using weighted interpolation. Simulation results show that the proposed method yields better video quality than conventional approaches.

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X-ray Absorption Near-edge Studies of Au1-xPtx alloys

  • Y.D. Chung;Lim, K.Y.;Lee, Y.S.;C.N.Whang;Park, B.S.;Y.Jeon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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    • pp.164-164
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    • 2000
  • Since Au-Pt alloys have various atomic structures depending upon composition and annealing temperature, it is very interesting to investigate the electronic structures of alloys. We studied the changes of the electronic structure I the Au-Pt alloys by x-ray absorption near edge spectroscopy (XANES). Two kinds of Au-Pt alloy samples were prepared by arc melting methods and ion-beam-mixing technique. The Pt L2, 3-edge and Au L2, 3-edge X-ray absorption spectra (XPS) were measured with the electron yield mode detector at the 3C1 beam line of the Pohang Light Source (PLS). It was found that there was a substantial decrease in the area of the Pt L2, 3 white lines compared with that of pure Pt. The observed decrease in white line area was attributed to an increase in the number of pure Pt. The observed decrease in white line area was attributed to an increase in the number of 5d-electrons at the Pt site upon alloy formation. However, the Au L2, 3 edge spectra for Au-Pt alloys are all similar to that of pure Au. This implies that the 5d hole count of Au is not changed by alloy formation with Pt.

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Z-map을 이용한 임의의 절삭영역에서의 볼 엔드밀의 절삭력 예측에 관한 연구 (The Study on the Cutting Force Prediction in the Ball-End Milling Process at the Random Cutting Area using Z-map)

  • 김규만
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.125-129
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    • 1996
  • In this study, a method is proposed for the cutting force prediction of Ball-end milling process using Z-map is proposed. Any types of cutting area generated from previous cutting process can be expressed in z-map data. Cutting edge of a ball-end mill is divided into a set of finite cutting edges and the position of this edge is projected to the cross-section plane normal to the Z-axis. Comparing this projected position with Z-map data of cutting area and determining whether it is in the cutting region, total cutting force can be calculated by means of numerical integration. A series of experiments such as side cutting and upward/downard cutting was performet to verify the simulated cutting force.

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한국산 무당벌레(harmonia axyridis)의 유전학적 연구 3. 남부집단의 초혈반문 및 초혈벽의 변이에 관하여 (Genetic Studies on the Lady-Beetle , Harmonia axyridis Pallace, Population in Korea 3. Variation of elytral pattern and elytral edge in southern population)

  • 강영선;김창효
    • 한국동물학회지
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    • 제8권1호
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    • pp.8-10
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    • 1965
  • 1. We have observed the frequency , geographi variation and microgeographic variation of the elytral pattern types and the elytral edge of the population of Lady-beetle, Harmonia axyridis PALLACE, collected in Jinju and other 6 localitites in South Korea. 2. the number of specimen collected were 6,625 in which Succinea was 90.32% : Axyridis ; 0.74% : Spectabilis , 3.82% ; and Conspicua 5.07%. 3. We have found that 92.26% of all specimens have elytral edge. 4. There were some differences in the compositional of the elytral pattern types and elytral edge to the population among the Western seaside , inland and southern seaside of South Korea , whereas as great difference was in the compositional proportion tot he population of Spectabilis between the western and southern seaside . There was also a gret difference of the elytral edge between the inland and southern seaside. 5. A micro-geographic variation was observed in Jinju , located on southern area of South Korea. In the samples collected from the pine trees at Jinju area the Succinea occupied 73.25%, and 69.61 % were found to be provided with elytral edge, while in the general population 92.46% of specimen were Succinea and 98.35% were found to have elytral edge.

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