• Title/Summary/Keyword: Boundary Matching

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Contour Shape Matching based Motion Vector Estimation for Subfield Gray-scale Display Devices (서브필드계조방식 디스플레이 장치를 위한 컨투어 쉐이프 매칭 기반의 모션벡터 추정)

  • Choi, Im-Su;Kim, Jae-Hee
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.327-328
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    • 2007
  • A contour shape matching based pixel motion estimation is proposed. The pixel motion information is very useful to compensate the motion artifact generated at the specific gray level contours in the moving image for subfield gray-scale display devices. In this motion estimation method, the gray level boundary contours are extracted from the input image. Then using contour shape matching, the most similar contour in next frame is found, and the contour is divided into segment unit. The pixel motion vector is estimated from the displacement of the each segment in the contour by segment matching. From this method, more precise motion vector can be estimated and this method is more robust to image motion with rotation or from illumination variations.

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Pattern Recognition Method Using Fuzzy Clustering and String Matching (퍼지 클러스터링과 스트링 매칭을 통합한 형상 인식법)

  • 남원우;이상조
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.11
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    • pp.2711-2722
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    • 1993
  • Most of the current 2-D object recognition systems are model-based. In such systems, the representation of each of a known set of objects are precompiled and stored in a database of models. Later, they are used to recognize the image of an object in each instance. In this thesis, the approach method for the 2-D object recognition is treating an object boundary as a string of structral units and utilizing string matching to analyze the scenes. To reduce string matching time, models are rebuilt by means of fuzzy c-means clustering algorithm. In this experiments, the image of objects were taken at initial position of a robot from the CCD camera, and the models are consturcted by the proposed algorithm. After that the image of an unknown object is taken by the camera at a random position, and then the unknown object is identified by a comparison between the unknown object and models. Finally, the amount of translation and rotation of object from the initial position is computed.

Stereo Matching Using the Adaptive Patch Based on the Watershed (워터쉐드 기반의 적응 패치를 이용한 스테레오 정합 알고리즘에 관한 연구)

  • Woo-Sung Kil;Jong-Whang Jang
    • The Journal of Engineering Research
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    • v.6 no.2
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    • pp.99-107
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    • 2004
  • In stereo matching system, it is efficient using segment patch, which divides the image into homogeneous region in color or similar intensity, because it preserves the disparity boundary and disparity continuity in low textured region. But many miss matching occur in the highly textured region because of the over segmentation that makes patch small and ambiguous. In this paper, in order to solve problems, we propose adaptive patch matching based on the watershed image segmentation. Performance was verified in experimental results.

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Mode Matching Technique in a Cylindrical Cavity with Center Wire

  • Han, Dae Hyun
    • Journal of Multimedia Information System
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    • v.5 no.2
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    • pp.143-146
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    • 2018
  • The eigen value problem of a coaxial cavity and a modified pill box cavity is investigated using the mode matching technique. The coaxial cavity has a cylindrical cavity with beam ports and center conductor. The pill box cavity is the same as a coaxial cavity without center conductor. The electric field and magnetic field are formulated in propagation region and resonance region. The boundary and orthogonal conditions are applied to the electric and magnetic fields. We derived the eigen value equation by the proposed procedure in a coaxial cavity and a modified pill box cavity. The electromagnetic field of the real structure is disturbed by the coaxial wire. The effect of the coaxial wire in pill box cavity with beam ports increase the dominant resonant frequency. The coaxial line method of the coupling impedance is not adequate for a cylindrical cavity. The results of the mode matching technique and simulation agree well. The results confirm the proposed formulation is valid.

UNIVERSAL DISPERSION EQUATION FOR MAGNETOSTATIC WAVES(MSW)

  • Wenzhong, Hu
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.383-386
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    • 1995
  • A universal dispersion equation for magnetostatic waves(MSW) propagating in the film with arbitrary-multiple magnetic layers magnetized in an arbitrary direction was derived with a matching boundary condition method. The computing result curves of delay time were shown.

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Analysis of the Coplanar Waveguide Shielded by Rectangular Waveguide (구형 도파관으로 차폐된 코플래너 도파관 해석)

  • 황정섭;이상설
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.7
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    • pp.19-25
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    • 1993
  • By using the point matching method, the coplanar waveguide shielded by the rectangular waveguide has been analyzed. The particular potential solution of C.P.W has been obtained from the boundary condition by using the point matching method. The line capacitance has been obtained from the total charge of the center conductor per length. The effective dielectric constant and the line impedance have been obtained from the line capacitance of C.P.W.

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Measurement of relative geomatric errors between mating parts by using an omnidirectional image sensing system (OISSA) (전방향센서(OISSA)를 이용한 조립물체사이의 상대오차의 측정)

  • 김완수;조형석;김성권
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.820-823
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    • 1996
  • In contrast to parts of relatively simple shapes, it is important to match their cross-sectional shapes during mating parts of complicated shapes. It requires the 2.pi. information along their matching boundary to figure out their relative geometrical shapes. In this paper, we propose a method measuring a misalignment at the interface during mating parts with the complicated shapes by using the omnidirectional image sensing system(OLSSA). Also we carried out experiments in order to prove the method, and the results show the feasibility.

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Generation of a Turbulent Boundary Layer Using LES (LES를 이용한 난류경계층의 생성에 관한 연구)

  • Lim, Hee-Chang
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.8
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    • pp.680-687
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    • 2007
  • The paper presents a numerical simulation of flow of a turbulent boundary layer, representing a typical wind environment and matching a series of wind tunnel observations. The simulations are carried out at a Reynolds number of 20,000, based on the velocity U at a pseudo-height h, and large enough that the flow be effectively Reynolds number independent. Some wall models are proposed for the LES(Large Eddy Simulation) of the turbulent boundary layer over a rough surface. The Jenson number, $J=h/z_0$, based on the roughness length $z_0$, is 600 to match the wind tunnel data. The computational mesh is uniform with a spacing of h/32, as this aids rapid convergence of the multigrid solver, and the governing equations are discretised using second order finite differences within a parallel multiblock environment. The results presented include the comparison between wind tunnel measurements and LES computations of the turbulent boundary layer over rough surface.

A Boundary Curve Extraction Method using Triangular Elements of a Lightweight Model (경량 모델의 삼각 요소망으로부터 경계 곡선 추출 방법)

  • Kwon, Ki-Youn
    • Korean Journal of Computational Design and Engineering
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    • v.22 no.1
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    • pp.28-36
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    • 2017
  • Sharing of CAD data plays a key role in the PLM and a lightweight model is widely used for visualizing and sharing a large data. The lightweight model is mainly composed of triangular elements to minimize file size. There is no problem at all to visually confirm the shape based on these triangular elements but there is a limit to numerically calculate the exact position on the curve or surface. In this paper, a boundary curve generation method using triangular elements is proposed to increase the utilization of lightweight models. After matching connectivity of triangular elements, boundary element edges are extracted. Boundary curves are generated by connecting of these boundary element edges. This proposed method has been tested on several models to demonstrate the feasibility.

Rectangle Region Based Stereo Matching for Building Reconstruction

  • Wang, Jing;Miyazaki, Toru;Koizumi, Hirokazu;Iwata, Makoto;Chong, Jong-Wha;Yagyu, Hiroyuki;Shimazu, Hideo;Ikenaga, Takeshi;Goto, Satoshi
    • Journal of Ubiquitous Convergence Technology
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    • v.1 no.1
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    • pp.9-17
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    • 2007
  • Feature based stereo matching is an effective way to perform 3D building reconstruction. However, in urban scene, the cluttered background and various building structures may interfere with the performance of building reconstruction. In this paper, we propose a novel method to robustly reconstruct buildings on the basis of rectangle regions. Firstly, we propose a multi-scale linear feature detector to obtain the salient line segments on the object contours. Secondly, candidate rectangle regions are extracted from the salient line segments based on their local information. Thirdly, stereo matching is performed with the list of matching line segments, which are boundary edges of the corresponding rectangles from the left and right image. Experimental results demonstrate that the proposed method can achieve better accuracy on the reconstructed result than pixel-level stereo matching.

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