• Title/Summary/Keyword: Edge method

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Edge Profile Correction for Modulation Transfer Function on Digital X-ray Imaging System (디지털 의료영상에서 Edge method에 의한 Modulation Transfer Function 보정방법과 특이성)

  • Kim, Jung-Min
    • Journal of radiological science and technology
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    • v.30 no.3
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    • pp.251-257
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    • 2007
  • Medical imaging zero-phase-sequence component in estimation for picture that is gotten that importance weight of digital device is increased day by day at the same time also so much important. Special quality about resolution uses Modulation Transfer Function by representative method to evaluate sharpness on important element in image quality. Get MTF converting slit, differentiating this making composition ESF edge method uses Excel by edge method in this study to be composition LSF get in fourier to informed measuring mean universally. Such method is considered that can help in principle grasping of step before make Program using C language as many as Matlab.

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Efficient Use of MPEG-7 Edge Histogram Descriptor

  • Won, Chee-Sun;Park, Dong-Kwon;Park, Soo-Jun
    • ETRI Journal
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    • v.24 no.1
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    • pp.23-30
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    • 2002
  • MPEG-7 Visual Standard specifies a set of descriptors that can be used to measure similarity in images or video. Among them, the Edge Histogram Descriptor describes edge distribution with a histogram based on local edge distribution in an image. Since the Edge Histogram Descriptor recommended for the MPEG-7 standard represents only local edge distribution in the image, the matching performance for image retrieval may not be satisfactory. This paper proposes the use of global and semi-local edge histograms generated directly from the local histogram bins to increase the matching performance. Then, the global, semi-global, and local histograms of images are combined to measure the image similarity and are compared with the MPEG-7 descriptor of the local-only histogram. Since we exploit the absolute location of the edge in the image as well as its global composition, the proposed matching method can retrieve semantically similar images. Experiments on MPEG-7 test images show that the proposed method yields better retrieval performance by an amount of 0.04 in ANMRR, which shows a significant difference in visual inspection.

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Influence of the inclined edge notches on the shear-fracture behavior in edge-notched beam specimens

  • Haeri, Hadi
    • Computers and Concrete
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    • v.16 no.4
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    • pp.605-623
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    • 2015
  • A coupled experimental and numerical study of shear fracture in the edge-notched beam specimens of quasi-brittle materials (concrete-like materials) are carried out using four point bending flexural tests. The crack initiation, propagation and breaking process of beam specimens are experimentally studied by producing the double inclined edge notches with different ligament angles in beams under four point bending. The effects of ligament angles on the shear fracturing path in the bridge areas of the double edge-notched beam specimens are studied. Moreover, the influence of the inclined edge notches on the shear-fracture behavior of double edge-notched beam specimens which represents a practical crack orientation is investigated. The same specimens are numerically simulated by an indirect boundary element method known as displacement discontinuity method. These numerical results are compared with the performed experimental results proving the accuracy and validity of the proposed study.

Moving Object Contour Detection Using Spatio-Temporal Edge with a Fixed Camera (고정 카메라에서의 시공간적 경계 정보를 이용한 이동 객체 윤곽선 검출 방법)

  • Kwak, Jae-Ho;Kim, Whoi-Yul
    • Journal of Broadcast Engineering
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    • v.15 no.4
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    • pp.474-486
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    • 2010
  • In this paper, we propose a new method for detection moving object contour using spatial and temporal edge. In general, contour pixels of the moving object are likely present around pixels with high gradient value along the time axis and the spatial axis. Therefore, we can detect the contour of the moving objects by finding pixels which have high gradient value in the time axis and spatial axis. In this paper, we introduce a new computation method, termed as temporal edge, to compute an gradient value along the time axis for any pixel on an image. The temporal edge can be computed using two input gray images at time t and t-2 using the Sobel operator. Temporal edge is utilized to detect a candidate region of the moving object contour and then the detected candidate region is used to extract spatial edge information. The final contour of the moving object is detected using the combination of these two edge information, which are temporal edge and spatial edge, and then the post processing such as a morphological operation and a background edge removing procedure are applied to remove noise regions. The complexity of the proposed method is very low because it dose not use any background scene and high complex operation, therefore it can be applied to real-time applications. Experimental results show that the proposed method outperforms the conventional contour extraction methods in term of processing effort and a ghost effect which is occurred in the case of entropy method.

A method for underwater image analysis using bi-dimensional empirical mode decomposition technique

  • Liu, Bo;Lin, Yan
    • Ocean Systems Engineering
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    • v.2 no.2
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    • pp.137-145
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    • 2012
  • Recent developments in underwater image recognition methods have received large attention by the ocean engineering researchers. In this paper, an improved bi-dimensional empirical mode decomposition (BEMD) approach is employed to decompose the given underwater image into intrinsic mode functions (IMFs) and residual. We developed a joint algorithm based on BEMD and Canny operator to extract multi-pixel edge features at multiple scales in IMFs sub-images. So the multiple pixel edge extraction is an advantage of our approach; the other contribution of this method is the realization of the bi-dimensional sifting process, which is realized utilizing regional-based operators to detect local extreme points and constructing radial basis function for curve surface interpolation. The performance of the multi-pixel edge extraction algorithm for processing underwater image is demonstrated in the contrast experiment with both the proposed method and the phase congruency edge detection.

Edge Preserving using HOG Guide Filter for Image Segmentation (영상 분할을 위한 HOG 가이드 필터를 적용한 엣지 보존 기술)

  • OH, Young-Jin;Kang, Hang-Bong
    • Journal of Korea Multimedia Society
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    • v.18 no.10
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    • pp.1164-1171
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    • 2015
  • The edge preserving method is important for image storage and geometric transformation. In this paper, we propose a new edge preserving method using HOG-Guide filter for image segmentation. In our approach, we extract edge information using gradient histogram to set HOG guide line. Then, we use HOG guide line to smooth image. With two to four iterations of smoothing operations, we finally obtain desirable edge preserved image. Our experimental results showed good performances showing that our proposed method is better than other methods.

A Study on the Edge Construction of CMM Data Using a Method of Mean Curvature Block (평균곡률 구간법을 이용한 CMM 데이터의 경계 형성 연구)

  • Chang, Byoung-Chun;Kim, Dae-Il;Oh, Seok-Hyung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.1
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    • pp.74-80
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    • 2010
  • The purpose of reverse engineering design using 3D measurement data is an accurate reconstruction of real body. In oder to accomplish this object, it is important that creating exact extracting edges should be studying out first of all. This study used edge-based method to find out edge point from the measuring point data. The characteristics are analysed using the mean curvature block method on the fitting NURBS curve and defined edges through block removal condition. The results showed that only using the NURBS curve of maximum curvature analysis to define correct edge of real geometry is limited, but this segmentation approach provides simplified necessary condition for edge classification, and an effectiveness to classify a straight line, curves and fillets etc.

Analysis of Effect of an Additional Edge on Eigenvector Centrality of Graph

  • Han, Chi-Geun;Lee, Sang-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.1
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    • pp.25-31
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    • 2016
  • There are many methods to describe the importance of a node, centrality, in a graph. In this paper, we focus on the eigenvector centrality. In this paper, an analytical method to estimate the difference of centrality with an additional edge in a graph is proposed. In order to validate the analytical method to estimate the centrality, two problems, to decide an additional edge that maximizes the difference of all centralities of all nodes in the graph and to decide an additional edge that maximizes the centrality of a specific node, are solved using three kinds of random graphs and the results of the estimated edge and observed edge are compared. Though the estimated centrality difference is slightly different from the observed real centrality in some cases, it is shown that the proposed method is effective to estimate the centrality difference with a short running time.

Canard-Leading Edge Flap Scheduling for the Maneuverability Enhancement of a Fighter Class Aircraft (전투기급 항공기 기동성 증대를 위한 카나드-앞전플랩 스케줄링)

  • Chung, In-Jae;Kim, Sang-Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.35 no.2
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    • pp.165-170
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    • 2007
  • During the conceptual design phase of a wing-body-canard type fighter class aircraft, as a method of maneuverability enhancement for an aircraft, effects of canard-leading edge flap scheduling have been studied. In this study, corrected supersonic panel method has been used to predict the drag polar characteristics due to canard-leading edge flap deflections in the high speed regime. Utilizing the predicted drag polar curves, the canard-leading edge flap scheduling laws have been established. These scheduling laws are the relation of canard-leading edge flap deflections and the flight conditions to maximize the lift-drag ratio. Based on the results obtained from the canard-leading edge flap scheduling, the present method has shown to be useful to enhance the maneuverability of wing-body-canard type fighter class aircraft.

A Sufferage offloading tasks method for multiple edge servers

  • Zhang, Tao;Cao, Mingfeng;Hao, Yongsheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.11
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    • pp.3603-3618
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    • 2022
  • The offloading method is important when there are multiple mobile nodes and multiple edge servers. In the environment, those mobile nodes connect with edge servers with different bandwidths, thus taking different time and energy for offloading tasks. Considering the system load of edge servers and the attributes (the number of instructions, the size of files, deadlines, and so on) of tasks, the energy-aware offloading problem becomes difficult under our mobile edge environment (MCE). Most of the past work mainly offloads tasks by judging where the job consumes less energy. But sometimes, one task needs more energy because the preferred edge servers have been overloaded. Those methods always do not pay attention to the influence of the scheduling on the future tasks. In this paper, first, we try to execute the job locally when the job costs a lower energy consumption executed on the MD. We suppose that every task is submitted to the mobile server which has the highest bandwidth efficiency. Bandwidth efficiency is defined by the sending ratio, the receiving ratio, and their related power consumption. We sort the task in the descending order of the ratio between the energy consumption executed on the mobile server node and on the MD. Then, we give a "suffrage" definition for the energy consumption executed on different mobile servers for offloading tasks. The task selects the mobile server with the largest suffrage. Simulations show that our method reduces the execution time and the related energy consumption, while keeping a lower value in the number of uncompleted tasks.