• Title/Summary/Keyword: Local Projection method

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Registration of the 3D Range Data Using the Curvature Value (곡률 정보를 이용한 3차원 거리 데이터 정합)

  • Kim, Sang-Hoon;Kim, Tae-Eun
    • Convergence Security Journal
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    • v.8 no.4
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    • pp.161-166
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    • 2008
  • This paper proposes a new approach to align 3D data sets by using curvatures of feature surface. We use the Gaussian curvatures and the covariance matrix which imply the physical characteristics of the model to achieve registration of unaligned 3D data sets. First, the physical characteristics of local area are obtained by the Gaussian curvature. And the camera position of 3D range finder system is calculated from by using the projection matrix between 3D data set and 2D image. Then, the physical characteristics of whole area are obtained by the covariance matrix of the model. The corresponding points can be found in the overlapping region with the cross-projection method and it concentrates by removed points of self-occlusion. By the repeatedly the process discussed above, we finally find corrected points of overlapping region and get the optimized registration result.

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Adaptive nodal generation with the element-free Galerkin method

  • Chung, Heung-Jin;Lee, Gye-Hee;Choi, Chang-Koon
    • Structural Engineering and Mechanics
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    • v.10 no.6
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    • pp.635-650
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    • 2000
  • In this paper, the adaptive nodal generation procedure based on the estimated local and global error in the element-free Galerkin (EFG) method is proposed. To investigate the possibility of h-type adaptivity of EFG method, a simple nodal refinement scheme is used. By adding new node along the background cell that is used in numerical integration, both of the local and global errors can be controlled adaptively. These errors are estimated by calculating the difference between the values of the projected stresses and original EFG stresses. The ultimate goal of this study is to develop the reliable nodal generator based on the local and global errors that is estimated posteriori. To evaluate the performance of proposed adaptive procedure, the convergence behavior is investigated for several examples.

Evaluation of Histograms Local Features and Dimensionality Reduction for 3D Face Verification

  • Ammar, Chouchane;Mebarka, Belahcene;Abdelmalik, Ouamane;Salah, Bourennane
    • Journal of Information Processing Systems
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    • v.12 no.3
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    • pp.468-488
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    • 2016
  • The paper proposes a novel framework for 3D face verification using dimensionality reduction based on highly distinctive local features in the presence of illumination and expression variations. The histograms of efficient local descriptors are used to represent distinctively the facial images. For this purpose, different local descriptors are evaluated, Local Binary Patterns (LBP), Three-Patch Local Binary Patterns (TPLBP), Four-Patch Local Binary Patterns (FPLBP), Binarized Statistical Image Features (BSIF) and Local Phase Quantization (LPQ). Furthermore, experiments on the combinations of the four local descriptors at feature level using simply histograms concatenation are provided. The performance of the proposed approach is evaluated with different dimensionality reduction algorithms: Principal Component Analysis (PCA), Orthogonal Locality Preserving Projection (OLPP) and the combined PCA+EFM (Enhanced Fisher linear discriminate Model). Finally, multi-class Support Vector Machine (SVM) is used as a classifier to carry out the verification between imposters and customers. The proposed method has been tested on CASIA-3D face database and the experimental results show that our method achieves a high verification performance.

Solution Recovery Techniques for Posteriori Error Estimation (후처리 에러산정을 위한 가상해 도출방법)

  • Lee, Sang-Ho;Kim, Sang-Hyo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1996.04a
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    • pp.47-53
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    • 1996
  • An enhanced solution recovery method for recovering accurate derivatives such as moments, or shears, from finite element solutions for $C^{0}$ beam and plate is presented. In the enhanced method, the square of the residuals in the equilibrium equations is included. Results are compared with those of standard Zienkiewicz-Zhu methods. Numerical examples show that in the global projection, the enhanced technique improves the accuracy of projected solution significantly. In the local projection, the enhanced method circumvents the numerical ill-conditioning which occurs in some meshes, and usually recovers derivatives with better accuracy.y.

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A 2-D Barcode Detection Algorithm based on Local Binary Patterns (지역적 이진패턴을 이용한 2차원 바코드 검출 알고리즘)

  • Choi, Young-Kyu
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.2
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    • pp.23-29
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    • 2009
  • To increase the data capacity of one-dimensional symbology, 2D barcodes have been proposed a decade ago. In this paper, a new 2D barcode detection algorithm based on Local Binary Pattern is presented. To locate 2D barcode symbols, a texture analysis scheme based on the Local Binary Pattern is adopted, and a gray-scale projection with sub-pixel operation is utilized to separate the symbol precisely from the input image. Finally, the segmented symbol is normalized using the inverse perspective transformation for the decoding process. The proposed method ensures high performances under various lighting/printing conditions and strong perspective deformations. Experiments show that our method is very robust and efficient in detecting the symbol area for the various types of 2D barcodes.

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A Revision Restoring Projection after Nipple Reconstruction by Burying Four Triangular Dermal Flaps

  • Kim, Ji Hun;Ahn, Hee Chang
    • Archives of Plastic Surgery
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    • v.43 no.4
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    • pp.339-343
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    • 2016
  • Background Numerous techniques have been used to achieve long-term projection of the nipple following nipple-areola reconstruction. However, the reconstructed nipple loses projection over time. We describe a technique that uses local flaps to improve the lost projection of reconstructed nipples. Methods Between November 2013 and March 2015, nine patients (11 nipples) underwent revisional nipple reconstruction for lost projection. Only C-H nipple reconstructions were included in this study. The medical history of each patient was reviewed and photographs were taken in front and lateral views. All patients attended routine follow-up visits. Deepithelialized triangular flaps were made on all four sides of the nipple and buried in the opposite corners in order to augment the volume of the nipple. Anchoring sutures were used to attach each triangular flap on the side opposite their point of origin, and the resulting defects were closed directly. Results This procedure was used successfully in nine patients (11 nipples). Adequate projection was achieved in all patients and no complications occurred. The average nipple height was 3 mm before operation, 7 mm one day after operation, 5 mm at the six-month follow-up, and 5 mm at the 12-month follow-up. The average nipple-areolar angle was $164^{\circ}$ before the operation, $111^{\circ}$ one day after the operation, $130^{\circ}$ at the six-month follow-up, and $133^{\circ}$ at the 12-month follow-up. Conclusions The method described provides a solution to the loss of projection in reconstructed nipples. We recommend this technique because it leads to better projection, greater volume, and a more natural shape.

LOCAL CONVERGENCE OF THE SECANT METHOD UPPER $H{\ddot{O}}LDER$ CONTINUOUS DIVIDED DIFFERENCES

  • Argyros, Ioannis K.
    • East Asian mathematical journal
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    • v.24 no.1
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    • pp.21-25
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    • 2008
  • The semilocal convergence of the secant method under $H{\ddot{o}}lder$ continuous divided differences in a Banach space setting for solving nonlinear equations has been examined by us in [3]. The local convergence was recently examined in [4]. Motivated by optimization considerations and using the same hypotheses but more precise estimates than in [4] we provide a local convergence analysis with the following advantages: larger radius of convergence and finer error estimates on the distances involved. The results can be used for projection methods, to develop the cheapest possible mesh refinement strategies and to solve equations involving autonomous differential equations [1], [4], [7], [8].

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Acellular Dermal Matrix as a Core Strut for Projection in Nipple Reconstruction: Approaches for Three Different Methods of Breast Reconstruction

  • Park, Gui-Yong;Yoon, Eul-Sik;Cho, Hee-Eun;Lee, Byung-Il;Park, Seung-Ha
    • Archives of Plastic Surgery
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    • v.43 no.5
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    • pp.424-429
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    • 2016
  • Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A $1{\times}2-cm$ acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was $73.0%{\pm}9.67%$ for the LD flap group using an O-strut, $72.0%{\pm}11.53%$ for the TRAM flap group using an I-strut, and $69.0%{\pm}10.82%$ for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction.

De-interlacing Algorithm Using Integral Projection-based Motion Estimation Considering Region Of Interest (관심영역 단위의 적분 프로젝션기반 움직임 추정을 사용한 순차주사화 알고리즘)

  • Kim, Young-Duk;Chang, Joon-Young;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.3
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    • pp.20-29
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    • 2008
  • In this paper, we propose a do-interlacing algorithm using integral projection-based motion estimation considering Region Of Interest(ROI). The proposed motion estimation method finds the motion of the given ROI accurately with low computational cost. In order to incorporate the motion estimation in do-interlacing, an entire image is first segmented into multiple ROIs according to the temporally predicted block-wise motion types and spatial positions. Then, motion vectors of respective ROIs are obtained by the integral projection method. In this paper, totally five ROIs, one for the global motion and four for the local motions, are made, and therefore, five motion vectors are produced for each field. By using the estimated motion vectors, motion compensation is performed for increasing the vortical resolution of the converted frames. Finally, do-interlaced frames are obtained by effectively combining the results of motion compensation and stable intra-field do-interlacing according to the reliability of motion compensation. Experimental results show that the proposed algorithm provides better image quality than existing algorithms in both subjective and objective measures.

Cluster-based Linear Projection and %ixture of Experts Model for ATR System (자동 목표물 인식 시스템을 위한 클러스터 기반 투영기법과 혼합 전문가 구조)

  • 신호철;최재철;이진성;조주현;김성대
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.3
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    • pp.203-216
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    • 2003
  • In this paper a new feature extraction and target classification method is proposed for the recognition part of FLIR(Forwar Looking Infrared)-image-based ATR system. Proposed feature extraction method is "cluster(=set of classes)-based"version of previous fisherfaces method that is known by its robustness to illumination changes in face recognition. Expecially introduced class clustering and cluster-based projection method maximizes the performance of fisherfaces method. Proposed target image classification method is based on the mixture of experts model which consists of RBF-type experts and MLP-type gating networks. Mixture of experts model is well-suited with ATR system because it should recognizee various targets in complexed feature space by variously mixed conditions. In proposed classification method, one expert takes charge of one cluster and the separated structure with experts reduces the complexity of feature space and achieves more accurate local discrimination between classes. Proposed feature extraction and classification method showed distinguished performances in recognition test with customized. FLIR-vehicle-image database. Expecially robustness to pixelwise sensor noise and un-wanted intensity variations was verified by simulation.