• Title/Summary/Keyword: Visual

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Stereo Visual Odometry without Relying on RANSAC for the Measurement of Vehicle Motion (차량의 모션계측을 위한 RANSAC 의존 없는 스테레오 영상 거리계)

  • Song, Gwang-Yul;Lee, Joon-Woong
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.321-329
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    • 2015
  • This paper addresses a new algorithm for a stereo visual odometry to measure the ego-motion of a vehicle. The new algorithm introduces an inlier grouping method based on Delaunay triangulation and vanishing point computation. Most visual odometry algorithms rely on RANSAC in choosing inliers. Those algorithms fluctuate largely in processing time between images and have different accuracy depending on the iteration number and the level of outliers. On the other hand, the new approach reduces the fluctuation in the processing time while providing accuracy corresponding to the RANSAC-based approaches.

The Study of Visual Tool for Automated Ultrasonic Examination of the Piping Welds in NPP (자동 초음파 신호평가를 위한 비쥬얼도구에 관한 연구)

  • Yoo, Hyun Joo;Choi, Sung Nam;Kim, Hyung Nam;Lee, Hee Jong
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.6 no.1
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    • pp.9-15
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    • 2010
  • This paper describes the Visual Tool for automatic ultrasonic examination that is under developing as a part of the project for development of automatic ultrasonic wave acquisition and analysis program. This tool that is supported by various image processing techniques will be adopted to detect the flaws in the component and piping welds in NPP. Visual Tool will enhance the integrity of nuclear power plant. The object of this paper is to address the Visual Tool which is developing for automatic ultrasonic inspection of welds in NPP.

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Estimation of Visual Evoked Potentials Using Time-Frequency Analysis (시-주파수 분석법을 이용한 시각자극 유발전위에 관한 연구)

  • 홍석균;성홍모;윤영로;윤형로
    • Journal of Biomedical Engineering Research
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    • v.22 no.3
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    • pp.259-267
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    • 2001
  • The visual evoked potentials(VEPs) is used to assist in the diagnosis of specific disorders associated with involvement of the sensory visual pathways. The P100 latency is an important parameter which is diagnosis of optic nerve disorders. There are characteristics of latency delay, wave distortion, amplitude deduction in abnormal subjects. It is difficult to diagnose in the case of producing peak at the P100 latency. In this paper, difference of pattern between normal VEPs and abnormal VEPs using the Choi-Williams distribution method is studied. We observed the relationship about time and spectrum. The result shown that normal VEPs had maximum spectral value at 20Hz~26.7Hz and abnormal VEPs had maximum spectral value at 16.7Hz~20Hz. Also normal VEPs spectrum is higher than abnormal VEPs spectrum.

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A Study on the Visual Elevation Image of Apartment Buildings (아파트 입면계획에서 시각적 디자인 이미지에 관한 연구)

  • 손세욱;구시온
    • Journal of the Korean housing association
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    • v.10 no.2
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    • pp.247-257
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    • 1999
  • This study is aimed to propose the evaluation model of forecasting visual quality of apartment buildings, which would be a useful tool to make the architectural concepts corresponding to user needs. This study was carried out through the four-step experiments as follows. The first step is to take the user's visual evaluation construct. To do this, the 22 adjective phrases were extracted, which were applicable to all apartment buildings. The second step is to analyze the user's visual preference, which is measured by the user's psychological quantity on the apartment buildings by S. D.(Semantic Differential) Method. The third step is to analyzethe five psychological-factors obtained from the Factor Analysis. The perceptual images on the 41 experimental subjects were checked up through evaluating and analyzing the factor scores of each subjects for each psychological-factor. The fourth step is to analyze, the similarity of various characters in a building, which is mirrored on the user's psychological quantity and how buildings are grouped by it.

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STUDY ON THE VISUAL COGNITIVE CHARACTERISTICS BY THE FIXATION POINT ANALYSIS USING THE EYE MARK RECORDER

  • Yamanoto, Satoshi;Yamaoka, Toshiki;Matsunobe, Takuo
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2001.05a
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    • pp.20-25
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    • 2001
  • In recent years, the concern about a user center design in increasing, and it's needed to task a user's visual cognitive characteristics for information presentation. Then this study aims to grasp user's cognitive characteristics about the information presentation by analyzing the fixation points. In the experiment, actually subject operated a copy machine. Recorded the fixation point movement of the operation panel by the eye mark recorder. Analysis examined the screen interface of the operation panel from the field of a fixation point trace. The top down type fixation oder by experience or the context became clear as a result. Furthermore, the difference of the fixation order by skill level was also examined. In this study, it was assumed that to grasp the visual cognitive characteristics becomes the key of efficient information.

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A Study on the Visual Sensibility of Clothing Texture (의복재질의 시각적 감성연구)

  • 오해순;이경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.10
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    • pp.1412-1423
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    • 2002
  • The purpose of this study is to objectively explain the visual sensibility of clothing torture that satisfies the consumer's sensibility. The photo stimuli on clothing texture are divided into hard, soft transparent and brilliant. For the study of image 38 kinds of costume samples is used. The Study was measured by using Semantic Differential method. The subjects were 410 females in twenties. The data were analyzed by factor analysis, ANOVA, MDS and regression analysis. Data were analyzed by SPSS. The major findings of this research were as follows: 1. As a result of the factor analysis,5 factors of visual sensibility were consist of high qualities, touches, looks, lightness, and warmness or coolness.2. There were significant difference in visual sensibility based on classification of clothing texture.3. The clothing texture was classified as thin-full, flat-lumpy. 4. As a result of the regression analysis, preferences of consumers can be connected directly with buying behavior and satisfaction can be closely related with preferences and positive buying behavior.

A study on Precise Trajectory Tracking control of Robot system (로봇시스템의 정밀 궤적 추적제어에 관한 연구)

  • Lee, Woo-Song;Kim, Won-Il;Yang, Jun-Seok
    • Journal of the Korean Society of Industry Convergence
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    • v.18 no.2
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    • pp.82-89
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    • 2015
  • This study proposes a new approach to design and control for autonomous mobile robots. In this paper, we describes a fuzzy logic based visual servoing system for an autonomous mobile robot. An existing system always needs to keep a moving object in overall image. This mes difficult to move the autonomous mobile robot spontaneously. In this paper we first explain an autonomous mobile robot and fuzzy logic system. And then we design a fuzzy logic based visual servoing system. We extract some features of the object from an overall image and then design a fuzzy logic system for controlling the visual servoing system to an exact position. We here introduce a shooting robot that can track an object and hit it. It is illustrated that the proposed system presents a desirable performance by a computer simulation and some experiments.

An Analysis of Applicability of Visual Urban Model in Korea (Visual Urban 모형의 적용성 분석)

  • Lee Joon Ho;Kwon In Sub;Yoon Sei Eui;Lee Jong Tae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.340-344
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    • 2005
  • 본 연구에서는 도로 빗물받이의 차집효율을 분석하기 위하여 측구 부분을 대상으로 수리모형을 제작하여 실험을 실시하고, 실측된 결과를 FHWA의 범용프로그램인 Visual Urban 모형의 해석결과와 비교하여 이 모형의 국내 적용성을 분석하였다. 실험에는 국내 표준규격인 40x50cm의 쇠살대 유입구(grater inlet)를 사용하였으며, 측구의 유량은 도로의 차선 및 빗물받이의 간격을 고려하여 $4\~13{\ell}/sec$를 선택하였다. 도로의 종경사는 $2,\;4,\;6\%$를 선택하고, 측구의 횡경사는 $4,\;6,\;8\%$를 선택하여, 총 36회의 실험을 실시하였다. Visual Urban 모형을 적용하여 모의한 결과와 실측값을 비교한 결과 종$\cdot$횡경사가 작은 경우에는 오차의 범위가 $6\%$정도였으며 종경사 $4\%$, 횡경사 $8\%$이상이면 비교적 일치하였다.

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Visual Servo Control of Slender Manipulators Using an Approximate Jacobian Operator (근사 자코비안 연산자를 이용한 경량 매니퓰레이터의 시각 서보 제어)

  • Lee, Ho-Gil;Kim, Jin-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.12
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    • pp.1086-1092
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    • 2000
  • To realize a visual servo control of slender manipulators, two problems to be solved are analysed. The stability problem on so-called noncolocation control and the infinite order problem of the real Jacobian matrix caused by the elastic deformation are discussed. By considering the dynamic relations between rigid and elastic modes, a Jacobian operator is derived and the physical meaning is also explained. Then, for practical control, a simple control scheme using an approximate Jacobian is proposed and its stable conditions are proven by means of the $L_$2$ stability theory. The scheme is structurally similar to the conventional PD control laws, but external sensors(e. g. visual sensor) are used for positioning and internal sensors for damping. A good performance is obtained via control experiments of a slender two link manipulator.

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Fingerprint identific ation based on optical visual cryptography (광 비쥬얼 크립토그래피 를 이용한 지문인식)

  • Lee, Seng-Hyun
    • Journal of the Korea Computer Industry Society
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    • v.5 no.9
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    • pp.1069-1078
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    • 2004
  • We propose an individual authentication method based on optical visual cryptography in thata fingerprint data is processed by secret sharing method taking into account the optical visual cryptograph and a part of shared data transmitted through an open network. Whenever it is necessary, submitting his fingerprint with the other shared information can authenticate the owner of the fingerprint. The system efficiently identifies fingerprints through optical correlation, regardless of difficulties of acquisition of exact fingerprint imagein the various environments.

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