• Title/Summary/Keyword: reconstruction scheme

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Human error analysis in nuclear power plants based on a cognitive model (인지과정모형에 기반한 원자력발전소 인적오류 분석)

  • 윤완철;이용희;김영수
    • Journal of the Ergonomics Society of Korea
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    • v.13 no.2
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    • pp.33-41
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    • 1994
  • The paper presents a new scheme and a support system for the analysis sof hyman errors in nuclear power plants based on a cognitive model. We discusse the problems identified in current managerial analysis, and propose a new approach that frames the description of human activities according to a human decision making modle, so that it could provide a better reconstruction of a sequence of event suspected of involving human errors. This sophistcated approach becomes practical for the field application with the support of a computerized aiding system. The model-based event re-construction method is expected to enable the analysts to produce more informative reports, which in turn heop to derive appropriate counter- measures to reduce the possibility of the analyzed human errors.

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Local stereo matching using combined matching cost and adaptive cost aggregation

  • Zhu, Shiping;Li, Zheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.1
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    • pp.224-241
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    • 2015
  • Multiview plus depth (MVD) videos are widely used in free-viewpoint TV systems. The best-known technique to determine depth information is based on stereo vision. In this paper, we propose a novel local stereo matching algorithm which is radiometric invariant. The key idea is to use a combined matching cost of intensity and gradient based similarity measure. In addition, we realize an adaptive cost aggregation scheme by constructing an adaptive support window for each pixel, which can solve the boundary and low texture problems. In the disparity refinement process, we propose a four-step post-processing technique to handle outliers and occlusions. Moreover, we conduct stereo reconstruction tests to verify the performance of the algorithm more intuitively. Experimental results show that the proposed method is effective and robust against local radiometric distortion. It has an average error of 5.93% on the Middlebury benchmark and is compatible to the state-of-art local methods.

Implicit Incompressible flow solver on Unstructured Hybrid grids (비정렬 혼합 격자에서 내재적 방법을 이용한 비압축성 유동해석)

  • Kim, Jong-Tae;Kim, Yong-Mo;Maeng, Ju-Seong
    • Journal of computational fluids engineering
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    • v.3 no.2
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    • pp.17-26
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    • 1998
  • The three-dimensional incompressible Navier-Stokes equations have been solved by a node-centered finite volume method with unstructured hybrid grids. The pressure-velocity coupling is handled by the artificial compressibility algorithm and convective fluxes are obtained by Roe's flux difference splitting scheme with linear reconstruction of the solutions. Euler implicit method with Jacobi matrix solver is used for the time-integration. The viscous terms are discretised in a manner to handle any kind of grids such as tetragedra, prisms, pyramids, hexahedra, or mixed-element grid. Inviscid bump flow is solved to check the accuracy of high order convective flux discretisation. And viscous flows around a circular cylinder and a sphere are studied to show the efficiency and accuracy of the solver.

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DCT Based Image Reconstruction Scheme for Mobile Environment (무선환경을 고려한 DCT 계수 특성을 이용한 이미지 재구성 기법)

  • Yang, Seung-Jun;Park, Sung-Chan;Lee, Guee-Sang
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10a
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    • pp.759-762
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    • 2000
  • 무선 채널 네트웍은 광범위하고 높은 에러발생률의 특성이 있다. 에러발생으로 인한 패킷의 손상이나 분실의 경우 화질에 심각한 영향을 미치게 된다. 본 논문에서는 DCT(Discrete Cosine Transform)을 기반으로 하는 고 압축 이미지의 손상된 데이터를 복구하기 위해 DCT 영역내 계수들의 분포 특성과 인접한 블록간의 유사성을 이용한 간단한 이미지 재구성 기법을 제안한다. 이러한 기법은 DCT 기반의 다양한 응용에 적용이 가능하며 적은 계산량을 가짐으로써 시스템의 낮은 전력 소모를 유지하여 무선컴퓨팅환경의 응용에 적합할 것이다.

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저해상도 멀티스펙트랄 자료와 고 해상도 범색 영상 융합

  • Lee, Sang-Hun
    • Proceedings of the KSRS Conference
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    • 2008.03a
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    • pp.137-139
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    • 2008
  • This study presents an approach to reconstruct high-resolution imagery for multispectral imagery of low-resolution using panchromatic imagery of high-resolution. The proposed scheme reconstructs a high-resolution image which agrees with original spectral values. It uses a linear model of high-and low- resolution images and consists of two stages. In this study, an 1m RGB image was generated from 4m IKONOS multispectral data.

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Geophysical Surveys for Investigating the Groundwater Environment of the Chojeong, Chungbuk (충북 초정지역의 지하수환경 조사를 위한 지표지구물리탐사)

  • 김지수;한수형;김경호;신재우
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.11a
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    • pp.103-106
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    • 2000
  • Geophysical data sets from the Chojeong area in the Chungbuk-Do are compositely studied in terms of multi-attribute interpretation for the subsurface mapping of shallow fracture zones, associated with groundwater reservoir. Utilizing a GIS software, the attribute data are implemented to a database; a lineament from the satellite image, electrical resistivities and its standard deviation, radioactivity, seismic velocity, bedrock depth from exploration data. In an attempt to interpret 1-D electrical sounding data in 2-D and 3-D views, 2-D resistivities structures are firstly made by interpolating 1-D plots. Reconstruction of a resistivity volume is found to be an effective scheme for subsurface mapping of shallow fracture zones. Shallow fracture zones in the southeastern part of the study area are commonly correlated in the various exploration data.

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Optical Encryption System using a Computer Generated Hologram

  • Kim, Jong-Yun;Park, Se-Joon;Kim, Soo-Joong;Doh, Yang-Hoi;Kim, Cheol-Su
    • Journal of the Optical Society of Korea
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    • v.4 no.1
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    • pp.19-22
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    • 2000
  • A new image encoding and identification scheme is proposed for security verification by us-ing a CGH(computer generated hologram), random phase mask, and a correlation technique. The encrypted image, which is attached to the security product, is made by multiplying a QP- CGH(quadratic phase CGI) with a random phase function. The random phase function plays a key role when the encrypted image is decrypted. The encrypted image can be optically recovered by a 2-f imaging system and automatically verified for personal identification by a 4-f correlation system. Simulation results show the proposed method can be used for both the reconstruction of an original image and the recognition of an encrypted image.

MODELLING THE DYNAMICS OF THE LEAD BISMUTH EUTECTIC EXPERIMENTAL ACCELERATOR DRIVEN SYSTEM BY AN INFINITE IMPULSE RESPONSE LOCALLY RECURRENT NEURAL NETWORK

  • Zio, Enrico;Pedroni, Nicola;Broggi, Matteo;Golea, Lucia Roxana
    • Nuclear Engineering and Technology
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    • v.41 no.10
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    • pp.1293-1306
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    • 2009
  • In this paper, an infinite impulse response locally recurrent neural network (IIR-LRNN) is employed for modelling the dynamics of the Lead Bismuth Eutectic eXperimental Accelerator Driven System (LBE-XADS). The network is trained by recursive back-propagation (RBP) and its ability in estimating transients is tested under various conditions. The results demonstrate the robustness of the locally recurrent scheme in the reconstruction of complex nonlinear dynamic relationships.

Numerical simulation of gas-liquid two phase flow in micro tubes

  • Sunakawa, Hideo;Teramoto, Susumu;Nagashima, Toshio
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.341-346
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    • 2004
  • Motion of a bubble inside narrow tube is numerically studied. The numerical code assumes axi-symmetric incompressible flow field. The surface of the bubble is captured by VOF (Volume Of Fluid) method, and it is advected by MARS (Multiphase Advection and Reconstruction Scheme). Air bubble inside water is first studied, and it was found that a strong vortex, which is induced by the pressure difference caused by the surface tension, is formed at the rear part of the bubble. Then flow parameters are parametrically varied to understand the correlation between the bubble shape, the bubble velocity, and the flow parameters. The parametric study revealed that the aspect ratio of the bubble mainly depends on We number, and the oscillation of the bubble speeds is dependent on Re number.

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A Study on the Theoretical Schema for the Subsystem of Institutional Household Management - Focused on the Marketing Management (공공가정경영 하위체계의 이론적 틀 고찰과 재구성 - 마케팅관리 영역을 중심으로)

  • Song Hyerim;Kim Sunwoo
    • Journal of Family Resource Management and Policy Review
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    • v.9 no.2
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    • pp.93-110
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    • 2005
  • Improving the quality and level of the research of institutional household management is one of major issues in the field of study on family resource management and human ecology In this context the purposes of this study were to develop the scheme for the theoretical reconstruction of the subsystem in the institutional household management and to present the applicational contents focused on the marketing management. This study reached a conclusion that the marketing management has to include more practical contents such as PR(public relations), the development and management of supporters and volunteers in order to enhance the useful community resources.

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