• 제목/요약/키워드: transformation region

검색결과 542건 처리시간 0.019초

THE METHOD OF ASYMPTOTIC INNER BOUNDARY CONDITION FOR SINGULAR PERTURBATION PROBLEMS

  • Andargie, Awoke;Reddy, Y.N.
    • Journal of applied mathematics & informatics
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    • 제29권3_4호
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    • pp.937-948
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    • 2011
  • The method of Asymptotic Inner Boundary Condition for Singularly Perturbed Two-Point Boundary value Problems is presented. By using a terminal point, the original second order problem is divided in to two problems namely inner region and outer region problems. The original problem is replaced by an asymptotically equivalent first order problem and using the stretching transformation, the asymptotic inner condition in implicit form at the terminal point is determined from the reduced equation of the original second order problem. The modified inner region problem, using the transformation with implicit boundary conditions is solved and produces a condition for the outer region problem. We used Chawla's fourth order method to solve both the inner and outer region problems. The proposed method is iterative on the terminal point. Some numerical examples are solved to demonstrate the applicability of the method.

컴퓨터 화상처리를 이용한 차량번호판 추출방법 (An Extraction Medthod of Car Number Plates by Computer Picture Processing)

  • 崔亨振;吳永煥;Takeshi Agui;Masayuki Nakajima
    • 대한전자공학회논문지
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    • 제24권2호
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    • pp.309-314
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    • 1987
  • Using computer picture processing, a method of extracting the region of a car number plate is described. A modified Hough transformation, in which parameter plane is restricted, is proposed. The demerits of Hough transformation, i.e., it requires much computation time and storage capacity, are reduced by this method. Further, taking the features of a car number plate into consideration, the region of a car number plate is extracted.

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고등식물 형질전환용 유전자 운반체 pKCHI의 개발 (Development of a Plant Transformation Vector, pKCHI)

  • 정상호
    • Journal of Plant Biology
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    • 제32권1호
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    • pp.23-32
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    • 1989
  • We have developed a plasmid vector, pKCH1, for the purpose of higher plant transformation. It contains the promoter region of cauliflower mosaic virus 35S transcript (P35s) and the terminator region of nopaline synthase gene (Tnos) with unique cloning sites, Bam HI and Xba I, between them. After inserting a foreing gene at the cloning sites, P35s-foreign gene-Tnos cassette can be recovered by using a restriction enzyme Hind III.

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탄소강 담금질시의 상변태열과 이를 포함한 냉각곡선의 계산 (The Latent Heat of Phase Transformation of the Carbon Steel and the Calculation of Cooling Curves Including the Latent Heat in Quenching)

  • 윤석훈;김경근
    • Journal of Advanced Marine Engineering and Technology
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    • 제18권3호
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    • pp.10-16
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    • 1994
  • This study aimed at measuring the latent heat of phase transformation of S45C carbon steel in quenching and at conducting the analytical researches into the calculation of cooling curves including the latent heat. The temperature of phase transformation of steel and its latent heat are dependant upon the cooling rates at the temperature of A1 phase transformation point. The effect of the latent heat of phase transformation is especially manifest at the cooling curve of center of specimens. The higher the cooling rates became, the lower fell the temperature region of phase transformation. In the figures of cooling rates, the phenomena of cooling rate dropping into zero was caused by the latent heat of phase transformation.

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Performance of Human Skin Detection in Images According to Color Spaces

  • Kim, Jun-Yup;Do, Yong-Tae
    • 한국정보기술응용학회:학술대회논문집
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    • 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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    • pp.153-156
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    • 2005
  • Skin region detection in images is an important process in many computer vision applications targeting humans such as hand gesture recognition and face identification. It usually starts at a pixel-level, and involves a pre-process of color spae transformation followed by a classification process. A color space transformation is assumed to increase separability between skin classes and other classes, to increase similarity among different skin tones, and to bring a robust performance under varying imaging conditions, without any complicated analysis. In this paper, we examine if the color space transformation actually brings those benefits to the problem of skin region detection on a set of human hand images with different postures, backgrounds, people, and illuminations. Our experimental results indicate that color space transfomation affects the skin detection performance. Although the performance depends on camera and surround conditions, normalized [R, G, B] color space may be a good choice in general.

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에너지 감쇠영역으로 인한 파랑변형 (Wave Transformation Due to Energy Dissipation Region)

  • 윤종태
    • 한국해안해양공학회지
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    • 제11권3호
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    • pp.135-140
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    • 1999
  • 에너지 감쇠역으로 인한 파의 변형을 모의하기 위하여 타원형 수치모형을 구성하였다. 해석방정식은 에너지 감쇠항이 추가된 타원형 완경사 방정식을 사용하였다. 개방경계조건에는 포물형 가정을 도입하였고 이를 위해 수치기법으로는 GCGM을 사용하였다. 원형감쇠역에 대한 수치실험을 통하여 감쇠역 전부에서의 반사파의 생성, 감쇠효과에 의한 파고감소 등을 확인할 수 있었고 해석해와 잘 일치하였다. 사각형 감쇠역에 대한 실험을 통하여 감쇠계수의 크기에 따른 파고분포의 변화를 살펴보았고 감쇠역 주변에서는 회절효과에 의한 파고의 증가가 매우 완만히 진행됨을 확인하였다. 이러한 수치실험을 통하여 에너지 감쇠구조 또한 반복기법을 사용한 타원형 수치모형으로 잘 모의할 수 있음을 확인하였다.

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관통 시험된 성형장약탄 라이너와 타겟 재료에 있어서의 미세조직 변화 (MICROSTRUCTURAL EVOLUTION OF SHAPEO-CHARGE LINER AND TARGET MATEREALS DURING BALLISTIC TEST)

  • 홍문희;이성;노준웅;백운형
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2001년도 추계학술강연 및 발표대회
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    • pp.46-46
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    • 2001
  • The microstructure of the 1020 mild steel target in the region ahead of craters, made by colliding against Cu and W-Cu shaped-charge jets. has been investigated in the present work. The region ahead of the crater impacted by the Cu shaped-charge jet reveals grain refinement implying the formation of sub-grains, while that of W-Cu one leads to martensitic transformation indicating that the region was heated up to an austenitic region which was followed by rapid cooling. The pressure of W-Cu shaped-charge jet impacting against the target when calculated is higher than that of Cu one. The microhardness of the region ahead of the crater impacted by the W-Cu shaped-charge jet is also higher than that of the Cu one. The microstructure of W-Cu slug that remains inside of the crater depicts the occurrence of the remarkable elongation of W particles during the liner collapse. The microstructural evolution of the region ahead of the crater is discussed on the basis of the pressure dependency of the ferrite/austenite transformation in the steel.

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복수의 거리영상 간의 변환계수의 추출 (Registration multiple range views)

  • 정도현;윤일동;이상욱
    • 전자공학회논문지S
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    • 제34S권2호
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    • pp.52-62
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    • 1997
  • To reconstruct the complete 3-D shape of an object, seveal range images form different viewpoints should be merged into a single model. The process of extraction of the transformation parameters between multiple range views is calle dregistration. In this paper, we propose a new algorithm to find the transformation parameters between multiple range views. Th eproposed algorithm consists of two step: initial estimation and iteratively update the transformation. To guess the initial transformation, we modify the principal axes by considering the projection effect, due to the difference fo viewpoints. Then, the following process is iterated: in order to extract the exact transformation parameters between the range views: For every point of the common region, find the nearest point among the neighborhood of the current corresponding point whose correspondency is defined by the reverse calibration of the range finder. Then, update the transformation to satisfy the new correspondencies. In order to evaluate the performance the proposed registration algorithm, some experiments are performed on real range data, acquired by space encoding range finder. The experimental results show that the proposed initial estimation accelerate the following iterative registration step.

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연속압출공정의 동력계산에 대한 연구 (A study on the total power calculation in the CONFORM process)

  • 김강수;박근배;김영호;곽인섭
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.105-109
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    • 1996
  • The calculation of the total power required at the Continuous Extrusion Forming(CONFORM) has been performed by the theoretical analysis of three transformation regions(primary grip length and extrusion grip length, flashing). In this study, that was performed by five transformation regions(biting, upsetting, filling, extruding, flashing)and four transformation regions(biting, upsetting and filling, extruding, flashing) and then results of theoretical analyses were compared with experimental results. Results of analysis by four and five transformation regions than that of three transformation regions in the CONFORM showed in a good agreement with experimental results.

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고온강재의 담금질 전열에 관한 연구 (A Study on the Heat Transfer of the High Temperature Metals in Quenching - The Latent Heat of Phase Transformation and Cooling Curves -)

  • 윤석훈
    • 수산해양기술연구
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    • 제27권4호
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    • pp.321-327
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    • 1991
  • Experiments of quenching were made with cylindrical specimens of carbon steel S45C of diameters from 12 to 30mm were performed. The specimens were heated by electric furnace and quenched by immersion method. In order to analyze the temperature profile(cooling curves) of carbon steel including the latent heat of phase transformation, nonlinear heat conduction problem was calculated by the numerical method of inverse heat conduction problem using the apparent heat capacity method. The difference between the calculated and the experimented cooling curves was caused by the latent heat of phase transformation, and the effects of the latent heat were especially manifest at the cooling curves of center of specimens. The temperature and the quantity of the latent heat of phase transformation depend on the cooling speed at A sub(1) transformation point, and the region for cooling speed to become zero was caused by the latent heat of phase transformation.

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