• Title/Summary/Keyword: restoration method

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A FAST LAGRANGE METHOD FOR LARGE-SCALE IMAGE RESTORATION PROBLEMS WITH REFLECTIVE BOUNDARY CONDITION

  • Oh, SeYoung;Kwon, SunJoo
    • Journal of the Chungcheong Mathematical Society
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    • v.25 no.2
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    • pp.367-377
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    • 2012
  • The goal of the image restoration is to find a good approximation of the original image for the degraded image, the blurring matrix, and the statistics of the noise vector given. Fast truncated Lagrange (FTL) method has been proposed by G. Landi as a image restoration method for large-scale ill-conditioned BTTB linear systems([3]). We implemented FTL method for the image restoration problem with reflective boundary condition which gives better reconstructions of the unknown, the true image.

A Restoration Method Using Duplication Paths in MPLS Networks (MPLS 망에서 이중화 경로를 이용한 복구 방법)

  • Kim, Eung-Ha;Cho, Young-Jong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.11
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    • pp.1-11
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    • 2002
  • To increase network survivability and to guarantee reliable services in MPLS networks, when failures occur either at any link or node of a working path, traffics on the failed path should be switched to other restoration paths. In this paper, we propose a path restoration method using duplication of working paths for link failure and its associated failure detection method, which utilizes OAM cells when all the duplicated links or nodes of the path failed. We analyze the performance of the proposed restoration method and show that especially the method is very efficient to restore high priority traffics. Also, through simulation we prove that the proposed restoration method is superior in performance to several existing methods suggested so far.

A New Algorithm of The Line to Ground Fault Section Isolation & Restoration in Ungrounded Distribution Power System (비접지 배전 계통에서 지락사고 시 고장구간 분리 및 복구를 위한 새로운 알고리즘)

  • Choi In. S.;Choi Myeon. S.;Lim Seong. I.;Lee Seung. J.
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.10
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    • pp.550-555
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    • 2004
  • Fault section isolation and service restoration are very important for function of DAS. In Japan, a progressive protection method is used for the line to ground fault section isolation and service restoration. But the progressive protection method has a drawback that the customer will experience outage time and that the rate in use of the feeder is not over 50%. This paper presents a new Service Restoration Algorithm which is for the line to ground fault section isolation and service restoration method for a ungrounded distribution system. If the proposed algorithm is used, the rate in use of the feeder can improve than before because a distribution system can change multi connection of feeder and the customer's outage time can be reduced. The proposed algorithm has been successfully tested in a distribution system.

The Development of Multi-Fault Restoration Algorithm for Distribution Network (배전계통 광역 정전복구 알고리즘 개발)

  • Jung, Jin-Soo;Lee, Seung-Jae;Jung, Jong-Wook;Lim, Young-Bae;Bae, Seok-Myung;Yi, Geon-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.3
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    • pp.69-77
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    • 2006
  • This paper presents the service restoration in electric power distribution systems. The aim of the service restoration is to control an emergency taken place in distribution systems and to restore out-of service areas as soon as possible when a fault occurs in distribution systems. For this reason, new service restoration strategies in multi-outage area are suggested in this paper. The suggested algorithm consist of two schemes. One is an individual restoration scheme, the other is an integrated restoration scheme. The former determines a restoration order of outage areas based on a restoration index. Unless the former scheme can generate a feasible restoration plan, the latter one will try to find out a new configuration without an overloaded section through tie exchange method.

Image Restoration Algorithms by using Fisher Information (피셔 인포메이션을 이용한 영상 복원 알고리즘)

  • 오춘석;이현민;신승중;유영기
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.6
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    • pp.89-97
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    • 2004
  • An object to reflect or emit light is captured by imaging system as distorted image due to various distortion. It is called image restoration that estimates original object by removing distortion. There are two categories in image restoration method. One is a deterministic method and the other is a stochastic method. In this paper, image restoration using Minimum Fisher Information(MFI), derived from B. Roy Frieden is proposed. In MFI restoration, experimental results to be made according to noise control parameter were investigated. And cross entropy(Kullback-Leibler entropy) was used as a standard measure of restoration accuracy, It is confirmed that restoration results using MFI have various roughness according to noise control parameter.

Effect of Inverse Filter in Image Restoration Using Hunt's Method (Hunt 방법을 이용한 Image Restoration에 있어서의 인버스 필터 효과)

  • Lee, Seong-Chun;Gang, Cheol-Ho;Lee, Jeong-Han
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.21 no.2
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    • pp.54-60
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    • 1984
  • In this paper, the modified Hunt's constrained least squares estimation method for image restoration is studied with the parameter ${\alpha}$ which represents the effect of inverse filter, And it is akown that high frequency components in the restored image obtained by the proposed method are emphasized by optimizing the constraining factor ${\gamma}$, depending upon ${\alpha}$.

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Cloud Detection and Restoration of Landsat-8 using STARFM (재난 모니터링을 위한 Landsat 8호 영상의 구름 탐지 및 복원 연구)

  • Lee, Mi Hee;Cheon, Eun Ji;Eo, Yang Dam
    • Korean Journal of Remote Sensing
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    • v.35 no.5_2
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    • pp.861-871
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    • 2019
  • Landsat satellite images have been increasingly used for disaster damage analysis and disaster monitoring because they can be used for periodic and broad observation of disaster damage area. However, periodic disaster monitoring has limitation because of areas having missing data due to clouds as a characteristic of optical satellite images. Therefore, a study needs to be conducted for restoration of missing areas. This study detected and removed clouds and cloud shadows by using the quality assessment (QA) band provided when acquiring Landsat-8 images, and performed image restoration of removed areas through a spatial and temporal adaptive reflectance fusion (STARFM) algorithm. The restored image by the proposed method is compared with the restored image by conventional image restoration method throught MLC method. As a results, the restoration method by STARFM showed an overall accuracy of 89.40%, and it is confirmed that the restoration method is more efficient than the conventional image restoration method. Therefore, the results of this study are expected to increase the utilization of disaster analysis using Landsat satellite images.

Finite Step Method for the Constrained Optimization Problem in Phase Contrast Microscopic Image Restoration

  • Adiya, Enkhbolor;Yadam, Bazarsad;Choi, Heung-Kook
    • Journal of Multimedia Information System
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    • v.1 no.1
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    • pp.87-93
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    • 2014
  • The aim of microscopic image restoration is to recover the image by applying the inverse process of degradation, and the results facilitate automated and improved analysis of the image. In this work, we consider the problem of image restoration as a minimization problem of convex cost function, which consists of a least-squares fitting term and regularization terms with non-negative constraints. The finite step method is proposed to solve this constrained convex optimization problem. We demonstrate the convergence of this method. Efficiency and restoration capability of the proposed method were tested and illustrated through numerical experiments.

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Ecological Restoration Planting Design Awareness Survey (생태복원 사업에서의 식재 설계에 관한 인식 조사)

  • Cho, Dong-gil
    • Journal of Environmental Science International
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    • v.31 no.7
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    • pp.579-592
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    • 2022
  • Much controversy has been generated over whether the ecological restoration project in Korea is faithful to the basic approach of ecological restoration compared to projects aimed at creating parks or green spaces. This study was aimed at understanding the level of awareness of practitioners in the planting design method, which is recognized as relatively important in landscape architecture and ecological restoration. The proficiency of practitioners in planting design techniques for ecological restoration projects was investigated and analyzed in seven areas: overall planting design awareness, plant species selection method, planting tree sizes, planting density, use of native species, vegetation climatic zone, soil environment, and weed control. There was no statistically significant difference between the group who thought they were experts in the field of ecological restoration and the group who thought they were experts in the field of parks and green spaces. Moreover, there was no statistically significant difference between the degree of work performance, that is, the group whose main industry was ecological restoration, the group that performed relatively more ecological restoration work, and the group that rarely performed it. Therefore, to apply desirable ecological restoration techniques in the future and to clearly differentiate between the approach in the field of parks and green spaces, the appropriate tree size or planting density selected in the ecological restoration planting design stage must be chosen. To this end, the awareness of expert groups must be improved and related laws, systems, and guidelines must be revised.

FIXED-POINT-LIKE METHOD FOR A NEW TOTAL VARIATION-BASED IMAGE RESTORATION MODEL

  • WON, YU JIN;YUN, JAE HEON
    • Journal of applied mathematics & informatics
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    • v.38 no.5_6
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    • pp.519-532
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    • 2020
  • In this paper, we first propose a new total variation-based regularization model for image restoration. We next propose a fixed-point-like method for solving the new image restoration model, and then we provide convergence analysis for the fixed-point-like method. To evaluate the feasibility and efficiency of the fixed-point-like method for the new proposed total variation-based regularization model, we provide numerical experiments for several test problems.