• Title/Summary/Keyword: reconstruction method

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150 Consecutive Cases of Delayed Post Mastectomy Reconstruction with TRAM Flap and Results (유경횡복직근피판을 이용한 유방절제술 후 지연재건 150례 및 결과)

  • Jung, In-Uk;Lee, Taik-Jong
    • Archives of Plastic Surgery
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    • v.38 no.1
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    • pp.19-26
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    • 2011
  • Purpose: This is the report on the results of 150 consecutive cases of delayed postmastectomy reconstruction with TRAM flap performed by single surgeon. The purpose of this study is to review the merits, demerits and other considerations of this method by analyzing the results. Methods: 150 patients were reviewed retrospectively who had breast reconstruction by a single surgeon from July 2001 to July 2008. Reviewed factors include demographic factors, mastectomy method, adjuvant therapies (such as radiation, chemotherapy) complication rate, simultaneous contralateral breast procedure rate, secondary touch-up procedure rate, and patients' satisfaction. Results: Ovarall TRAM flap complication rate was 22.6%. Among them, donor site complication rate was 36%, simultaneous contralateral breast procedure rate was 44.6%, secondary touch-up procedure rate was 40%. All rates were higher compared to immediate reconstruction with TRAM flap. But the patients' satisfaction was about the same as immediate reconstruction. Conclusion: Delayed postmastectomy reconstruction with TRAM flap can yield satisfactory results despite of relatively high complication rate and concomitant procedure rate when it is performed by a experienced surgeon.

Current Concepts in Reconstruction of Anterior Cruciate Ligament (전방십자인대 재건술의 경향)

  • Yoon, Kyoung Ho
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.12 no.1
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    • pp.1-7
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    • 2013
  • This article provides an overview of the current concepts regarding anterior cruciate ligament reconstruction, including anatomy, biomechanics, operative techniques and clinical results. Many techniques have been introduced for ACL reconstruction: single bundle reconstruction, remnant preserving augmentation, and double bundle reconstruction. Each technique has its strong and weak points, and it is not sure which technique is superior than others. It is considered to suggest that rather than to select the same method of surgery in all patients, select the method of reconstruction depending on the characteristics of the individual patient, the state of the residual ligaments and extent of the damage.

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Modified Directional Algebraic Reconstruction Technique Using Adjacent Current Pattern (인접전류패턴을 사용한 변형된 방향 대수적 영상복원법)

  • Kim, Ji Hoon;Kim, Chan Yong;Kim, Kyung Youn;Choi, Bong Yeol
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.12
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    • pp.256-264
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    • 2012
  • The directional algebraic reconstruction technique (DART) using the trigonometric current pattern is one of the image reconstruction algorithms in electrical impedance tomography (EIT). This method needs to compute resistances between electrode pairs as using relation between the injected currents and measured voltages for the reconstruction of the inner image. The delay time is incurred in this process. Therefore this paper proposes modified directional algebraic reconstruction technique (mDART) using the adjacent current pattern instead of the trigonometric current pattern to solve the delay time for initial resistance values. The proposed method uses measured voltages instead of computed resistances in the reconstruction algorithm. Hence this method can eliminate the delay time because it does not use the resistances. In conclusion, the proposed method improves image quality and image reconstruction time by using the adjacent current pattern. To prove performance of the proposed method, we carried on computer simulation of various cases.

Super Resolution Image Reconstruction using the Maximum A-Posteriori Method

  • Kwon Hyuk-Jong;Kim Byung-Guk
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.115-118
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    • 2004
  • Images with high resolution are desired and often required in many visual applications. When resolution can not be improved by replacing sensors, either because of cost or hardware physical limits, super resolution image reconstruction method is what can be resorted to. Super resolution image reconstruction method refers to image processing algorithms that produce high quality and high resolution images from a set of low quality and low resolution images. The method is proved to be useful in many practical cases where multiple frames of the same scene can be obtained, including satellite imaging, video surveillance, video enhancement and restoration, digital mosaicking, and medical imaging. The method can be either the frequency domain approach or the spatial domain approach. Much of the earlier works concentrated on the frequency domain formulation, but as more general degradation models were considered, later researches had been almost exclusively on spatial domain formulations. The method in spatial domains has three stages: i) motion estimate or image registration, ii) interpolation onto high resolution grid and iii) deblurring process. The super resolution grid construction in the second stage was discussed in this paper. We applied the Maximum A­Posteriori(MAP) reconstruction method that is one of the major methods in the super resolution grid construction. Based on this method, we reconstructed high resolution images from a set of low resolution images and compared the results with those from other known interpolation methods.

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A Comparative Study of Interface Reconstruction Algorithms in The Molten Metal Flow (주조유동 시뮬레이션에서 자유경계면 추적 기법 비교 연구)

  • Choi, Young-Sim;Hong, Jun-Ho;Hwang, Ho-Young
    • Journal of Korea Foundry Society
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    • v.31 no.3
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    • pp.124-129
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    • 2011
  • We applied two numerical schemes to improve accuracy of the solution in the flow simulation of molten metal. One method is Piecewise Linear Interface Calculation (PLIC) method and the other is Donor-Acceptor (D-A) method. In the present work, we have tested simple problems to verify the module of the interface reconstruction algorithms. After validations, accuracy and efficiency of these two methods have compared by simulating various real products. On the numerical simulation of free surface flow, it is possible for PLIC method to track very accurately the interface between phases. PLIC method, however, has the weak point where a lot of computational time hangs, though it shows the more accurate interface reconstruction. Donor-Acceptor method has enough effectiveness in the macro observation of mold filling sequence though it shows the inferior accuracy.

Image Reconstruction Method for Photonic Integrated Interferometric Imaging Based on Deep Learning

  • Qianchen Xu;Weijie Chang;Feng Huang;Wang Zhang
    • Current Optics and Photonics
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    • v.8 no.4
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    • pp.391-398
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    • 2024
  • An image reconstruction algorithm is vital for the image quality of a photonic integrated interferometric imaging (PIII) system. However, image reconstruction algorithms have limitations that always lead to degraded image reconstruction. In this paper, a novel image reconstruction algorithm based on deep learning is proposed. Firstly, the principle of optical signal transmission through the PIII system is investigated. A dataset suitable for image reconstruction of the PIII system is constructed. Key aspects such as model and loss functions are compared and constructed to solve the problem of image blurring and noise influence. By comparing it with other algorithms, the proposed algorithm is verified to have good reconstruction results not only qualitatively but also quantitatively.

3-D Inverse Radon Transform by Use of Tree-Structured Filter Bank

  • Morikawa, Yoshitaka;Murakami, Junichi
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.184-187
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    • 2002
  • Two-dimensional (2-D) X-ray computerized tomography (CT) equipments are widely used in industrial and medical fields, and nowadays studies on reconstruction algorithm for 3-D cone-beam acquisition systems are active for better utilization. The authors recent-By have proposed a fast reconstruction aigorithm using tree-structured filter bank for 2-D C1, and shown the algorithm is applicable to an approximate reconstruction of 3-D CT. For exact 3-D CT reconstruction, however, we have to backproject 1-D signal into 3-D space. This paper proposes a fast implementation method for this back-projection by use of tree-structured filter bank. and shows the proposed method works approximately 700 times faster than the direct one with almost same reconstruction image quality.

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Deformable Surface 3D Reconstruction from a Single Image by Linear Programming

  • Ma, Wenjuan;Sun, Shusen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.6
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    • pp.3121-3142
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    • 2017
  • We present a method for 3D shape reconstruction of inextensible deformable surfaces from a single image. The key of our approach is to represent the surface as a 3D triangulated mesh and formulate the reconstruction problem as a sequence of Linear Programming (LP) problems. The LP problem consists of data constraints which are 3D-to-2D keypoint correspondences and shape constraints which are designed to retain original lengths of mesh edges. We use a closed-form method to generate an initial structure, then refine this structure by solving the LP problem iteratively. Compared with previous methods, ours neither involves smoothness constraints nor temporal consistency, which enables us to recover shapes of surfaces with various deformations from a single image. The robustness and accuracy of our approach are evaluated quantitatively on synthetic data and qualitatively on real data.

Complete 3D Surface Reconstruction from Unstructured Point Cloud

  • Kim, Seok-Il;Li, Rixie
    • Journal of Mechanical Science and Technology
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    • v.20 no.12
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    • pp.2034-2042
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    • 2006
  • In this study, a complete 3D surface reconstruction method is proposed based on the concept that the vertices, of surface model can be completely matched to the unstructured point cloud. In order to generate the initial mesh model from the point cloud, the mesh subdivision of bounding box and shrink-wrapping algorithm are introduced. The control mesh model for well representing the topology of point cloud is derived from the initial mesh model by using the mesh simplification technique based on the original QEM algorithm, and the parametric surface model for approximately representing the geometry of point cloud is derived by applying the local subdivision surface fitting scheme on the control mesh model. And, to reconstruct the complete matching surface model, the insertion of isolated points on the parametric surface model and the mesh optimization are carried out. Especially, the fast 3D surface reconstruction is realized by introducing the voxel-based nearest-point search algorithm, and the simulation results reveal the availability of the proposed surface reconstruction method.

NURBS Surface Reconstruction from an Unstructured Point Cloud (비조직화된 점군으로부터 NURBS 곡면 모델의 생성)

  • Li, Ri-Xie;Kim, Seok-Il
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1564-1569
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    • 2007
  • This study concerns an advanced NURBS surface reconstruction method, which is based on the NURBS surface model fitting to the unstructured point cloud measured from an arbitrary complex shape. The concept of generating a simple triangular mesh model was introduced to generate a quadrilateral mesh model well-representing the topological characteristics of point cloud. The NURBS surface reconstruction processes required the use of the various methodologies such as QEM algorithm, merging scheme of pair-wise triangular mesh, creation algorithm of $G^1$ continuous tensor product NURBS surface patch, and so on. The effectiveness and reliability of the proposed NURBS surface reconstruction method were validated through the simulation results for the geometrically and topologically complex shapes.

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