• Title/Summary/Keyword: Principal axes

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Tracking of Moving Objects Using Morphological Segmentation, Statistical Moments and Hough Transform

  • Ahmad, Muhammad Bilal;Chang, Min-Hyuk;Park, Jong-An
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1377-1381
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    • 2003
  • This paper describes real time object tracking of 3D objects in 2D image sequences. The moving objects are segmented from the image sequence using morphological operations. The moving objects are segmented by the method of differential image followed by the process of morphological dilation. The moving objects are recognized and tracked using statistical moments. The direction of moving objects are determined by the Hough transform. The straight lines in the moving objects are found with the help of Hough transform. The direction of the moving object is calculated from the orientation of the straight lines in the direction of the principal axes of the moving objects. The direction of the moving object and the displacement of the object in the image sequence is used to calculate the velocity of the moving objects. The simulation results of the proposed method are promising on the test images.

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1 개의 TLD 를 이용한 건물의 양방향 진동제어 (Bi-directional response control of a building using one TLD)

  • 민경원;이성경;박은천
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2009년도 정기 학술대회
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    • pp.119-124
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    • 2009
  • This paper proposes a tuned liquid column sloshing damper(TLCSD) and presents experimental results to evaluate its control performance. The proposed damper acts as a tuned liquid column damper(TLCD) and a tuned liquid damper(TLD), respectively, in both principal axes of building structures. Shaking table test was performed to grasp its dynamic characteristics. Testing results showed that under inclined incident excitations, a TLCSD used in this study have dynamic characteristics coupled by both TLCD and TLD.

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유전자 알고리즘과 퍼지규칙을 기반으로한 지능형 자동감시 시스템의 개발 (A Fuzzy Logic System for Detection and Recognition of Human in the Automatic Surveillance System)

  • 장석윤;박민식;이영주;박민용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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    • pp.237-240
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    • 2001
  • An image processing and decision making method for the Automatic Surveillance System is proposed. The aim of our Automatic Surveillance System is to detect a moving object and make a decision on whether it is human or not. Various object features such as the ratio of the width and the length of the moving object, the distance dispersion between the principal axis and the object contour, the eigenvectors, the symmetric axes, and the areas if the segmented region are used in this paper. These features are not the unique and decisive characteristics for representing human Also, due to the outdoor image property, the object feature information is unavoidably vague and inaccurate. In order to make an efficient decision from the information, we use a fuzzy rules base system ai an approximate reasoning method. The fuzzy rules, combining various object features, are able to describe the conditions for making an intelligent decision. The fuzzy rule base system is initially constructed by heuristic approach and then, trained and tasted with input/output data Experimental result are shown, demonstrating the validity of our system.

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철근콘크리트 구조물의 유한요소 해석을 위한 균열모델 (Cracking Models in Finite Element Analysis of Reinforced Concrete Structure)

  • 최창근;정성훈
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1991년도 가을 학술발표회 논문집
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    • pp.23-28
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    • 1991
  • A simple, yet effective, material model of concrete is presented in this paper. Based on the orthotropic model in which the assumption of orthogonal principal strain axes is used, the incremental stress-strain relation of concrete is defined in the biaxial stress condition and the rotating crack model is adopted to represent realistically the change of the crack direction according to the different loading pad after cracking. Numerical results obtained from the finite element analysis are compared favourably with the available experimental data. By the parametric study, moreover, it was found that He most important factor in the structural behavior when the reinforced concrete structure is subjected to the dominent shear forces is the tension stiffening effect. The influences of the tension stiffening effect remarkably appears as the steel ratio decreases.

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복수의 거리영상 간의 변환계수의 추출 (Registration multiple range views)

  • 정도현;윤일동;이상욱
    • 전자공학회논문지S
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    • 제34S권2호
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    • pp.52-62
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    • 1997
  • To reconstruct the complete 3-D shape of an object, seveal range images form different viewpoints should be merged into a single model. The process of extraction of the transformation parameters between multiple range views is calle dregistration. In this paper, we propose a new algorithm to find the transformation parameters between multiple range views. Th eproposed algorithm consists of two step: initial estimation and iteratively update the transformation. To guess the initial transformation, we modify the principal axes by considering the projection effect, due to the difference fo viewpoints. Then, the following process is iterated: in order to extract the exact transformation parameters between the range views: For every point of the common region, find the nearest point among the neighborhood of the current corresponding point whose correspondency is defined by the reverse calibration of the range finder. Then, update the transformation to satisfy the new correspondencies. In order to evaluate the performance the proposed registration algorithm, some experiments are performed on real range data, acquired by space encoding range finder. The experimental results show that the proposed initial estimation accelerate the following iterative registration step.

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휨과 비틀림이 연계된 채널보의 진동 (Coupled flexural and torsional vibration of channel beam)

  • 김상환
    • 소음진동
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    • 제5권3호
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    • pp.327-335
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    • 1995
  • The study deals with the vibration of a beam whose flexural and centroidal axes are not coincident. The elementary bending-twisting theory is employed to derive the equation of motion, in which the effects of rotary inertia are added to the bending displacements and the effects of warping are added to the twist. Bending translation is restricted to one direction so that one bending equation is used instead of two. The equations of motion are solved by using the boundary value problem. The exact natural frequencies are fund from the frequency equation, which is obtained from the condition that the homogeneous system of algebraic equations representing the spatial solution shall not yield a trivial solution. The orthogonal conditions are established, and the principal mode equations of forced vibration are derived. As an example, the cantilevered beam is chosen and the first some natural frequencies and their modal shapes are found.

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A Force/Moment Direction Sensor and Its Application in Intuitive Robot Teaching Task

  • Park, Myoung-Hwan;Kim, Sung-Joo
    • Transactions on Control, Automation and Systems Engineering
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    • 제3권4호
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    • pp.236-241
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    • 2001
  • Teach pendant is the most widely used means of robot teaching at present. Despite the difficulties of using the motion command buttons on the teach pendant, it is an economical, robust, and effective device for robot teaching task. This paper presents the development of a force/moment direction sensor named COSMO that can improve the teach pendant based robot teaching. Robot teaching experiment of a six axis commercial robot using the sensor is described where operator holds the sensor with a hand, and move the robot by pushing, pulling, and twisting the sensor in the direction of the desired motion. No prior knowledge of the coordinate system is required. The function of the COSMO sensor is to detect the presence f force and moment along the principal axes of the sensor coordinate system. The transducer used in the sensor is micro-switch, and this intuitive robot teaching can be implemented at a very low cost.

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InP의 습식식각특성과 InP/lnGaAs HBT의 제작 (Wet etching charicteristics of InP in InP/InGaAs HBTs and their fabrication)

  • 김강대;박재홍;김용규;황성범;송정근
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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    • pp.77-80
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    • 2002
  • In this paper, InP-based HBTs have been optimally designed by numerical simulation and fabricated by the self-aligned process. The structure of HBT was designed in terms of the current gain*f$_{max}$ for the base and f$_{T}$*f$_{max}$ for the collector. The designed structure produced the current gain of about 50 and the cutoff frequency and the maximum oscillation frequency of 87GHz and 2940Hz respectively. In addition, we present a study of the vertical and lateral etching of InP with the mask sides parallel to the principal crystallographic axes, [0101 and (001). This etching characteristics arc used to fabricate self-aligned HBT structures with reduced parasitic effects.s.s.s.

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계층적 데이터 구조를 이용한 3차원 물체인식에 관한 연구 (A Study on 3-D Object Recognition using Hierarchical Data Structure)

  • 우광방;김영일
    • 대한전자공학회논문지
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    • 제27권6호
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    • pp.851-860
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    • 1990
  • This paper presents a recognition method which interprets 3-D object in terms of several silhouettes of quadtree and octree. Object representation used in object matching should be invariant with respect to locatin and orientation of the object. Generalized octree is projected on to image plane along the principal axes. Regular octree is made from orthogonal directions, but generalized octree is independent to viewing directions. Recognition process is achieved in two-stage matching. The quadtrees and octrees of unknown object with minimum dissimilarities are matched with the quadtrees and octrees of the models. So as to verify efficiency of 3-D object representation and accuracy of object recognition, experiments are performed for 14 different type of geometrical models and its results have been shown.

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Study on rectangular concrete-filled steel tubes with unequal wall thickness

  • Zhang, Yang;Yu, Chen-Jiang;Fu, Guang-Yuan;Chen, Bing;Zhao, She-Xu;Li, Si-Ping
    • Steel and Composite Structures
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    • 제22권5호
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    • pp.1073-1084
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    • 2016
  • Rectangular concrete-filled steel tubular columns with unequal wall thickness were investigated in the paper. The physical centroid, the centroidal principal axes of inertia, and the section core were given. The generalized bending formula and the generalized eccentric compression formula were deduced, and the equation of the neutral axis was also provided. The two rectangular concrete-filled steel tubular stub specimens subjected to the compression load on the physical centroid and the geometric centroid respectively were tested to verify the theoretical formulas.