• 제목/요약/키워드: vision-based techniques

검색결과 293건 처리시간 0.024초

지배주파수도를 이용한 미소 표면 결함 추출을 위한 영상 처리 알고리듬 (A visual inspection algorithm for detecting infinitesimal surface defects by using dominant frequency map)

  • 김상원;권인소
    • 제어로봇시스템학회논문지
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    • 제2권1호
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    • pp.26-34
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    • 1996
  • One of the challenging tasks in visual inspection using CCD camera is to identify surface defects in an image with complex textured backgeound. In microscopic view, the surface of real objects shows regular or random textured patterns. In this paper, we present a visual inspection algorithm to extract abnormal surface defects in an image with textured background. The algorithm uses the space and frequency information at the same time by introducing the Dominant Frequency Map(DFM) which can describe the frequency characteristics of every small local region of an input image. We demonstrate the feasibility and effectiveness of the method through a series of real experiments for a 14" TV CRT mold. The method successfully identifies a variety of infinitesimal defects, whose size is larger than $50\mu\textrm{m}$, of the mold. The experimental results show that the DFM based method is less sensitive to the environmental changes, such as illumination and defocusing, than conventional vision techniques.ques.

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MLESAC 움직임 추정 기반의 파티클 필터를 이용한 3D 얼굴 추적 (3D Face Tracking using Particle Filter based on MLESAC Motion Estimation)

  • 성하천;변혜란
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제16권8호
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    • pp.883-887
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    • 2010
  • 3D 얼굴 추적(Face tracking)은 보안감시, HCI(Human-Computer Interface), 엔터테인먼트(Entertainment)등 컴퓨터 비전과 관련된 여러 분야의 핵심 기술로서 많은 연구가 진행되고 있다. 하지만, 광범위한 응용분야에도 불구하고 3D 얼굴 추적의 기본적인 높은 연산 비용으로 인하여 그 응용 분야가 모바일 단말기 등의 저 사양 플랫폼에는 많은 한계가 있어왔다. 본 논문에서는 이러한 3D얼굴 추적의 연산 비용을 효과적으로 해결하고 폭 넓게 응용 분야를 확대하기 위하여 MLESAC(Maximum Likelihood Estimation by Sampling Consensus)을 이용한 움직임 추정(Motion Estimation) 기법과 기존의 파티클 필터(Particle Filter)를 결합하여 실행 속도 면에서 빠르면서도 성능 면에서도 우수한 3D 얼굴 추적 알고리즘을 제안한다.

불량애자 검출을 위한 비젼 기반 전파 신경망 (Propagation Neural Networks based on vision techniques for detecting of Faulty Insulator)

  • 김종만;김영민;황종선;박현철;임성호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.1097-1102
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    • 2002
  • For detecting of Faulty Insulator, a new Lateral Information Propagation Networks (LIPN) has been proposed. Energized insulator is reduced the rate of insulation extremely, and taken the results dirty and injured. It is necessary to be actions that detect the faulty insulator and exchange the new one. And thus, we have designed the LIPN to be detected that insulators by the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. Information propagates among neighbor nodes laterally and inter-node interpolation is achieved. Through several simulation experiments,real time reconstruction of the nonlinear image information is processed.

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Visual Sensing of the Light Spot of a Laser Pointer for Robotic Applications

  • Park, Sung-Ho;Kim, Dong Uk;Do, Yongtae
    • 센서학회지
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    • 제27권4호
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    • pp.216-220
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    • 2018
  • In this paper, we present visual sensing techniques that can be used to teach a robot using a laser pointer. The light spot of an off-the-shelf laser pointer is detected and its movement is tracked on consecutive images of a camera. The three-dimensional position of the spot is calculated using stereo cameras. The light spot on the image is detected based on its color, brightness, and shape. The detection results in a binary image, and morphological processing steps are performed on the image to refine the detection. The movement of the laser spot is measured using two methods. The first is a simple method of specifying the region of interest (ROI) centered at the current location of the light spot and finding the spot within the ROI on the next image. It is assumed that the movement of the spot is not large on two consecutive images. The second method is using a Kalman filter, which has been widely employed in trajectory estimation problems. In our simulation study of various cases, Kalman filtering shows better results mostly. However, there is a problem of fitting the system model of the filter to the pattern of the spot movement.

Estimation of Moving Information for Tracking of Moving Objects

  • Park, Jong-An;Kang, Sung-Kwan;Jeong, Sang-Hwa
    • Journal of Mechanical Science and Technology
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    • 제15권3호
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    • pp.300-308
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    • 2001
  • Tracking of moving objects within video streams is a complex and time-consuming process. Large number of moving objects increases the time for computation of tracking the moving objects. Because of large computations, there are real-time processing problems in tracking of moving objects. Also, the change of environment causes errors in estimation of tracking information. In this paper, we present a new method for tracking of moving objects using optical flow motion analysis. Optical flow represents an important family of visual information processing techniques in computer vision. Segmenting an optical flow field into coherent motion groups and estimating each underlying motion are very challenging tasks when the optical flow field is projected from a scene of several moving objects independently. The problem is further complicated if the optical flow data are noisy and partially incorrect. Optical flow estimation based on regulation method is an iterative method, which is very sensitive to the noisy data. So we used the Combinatorial Hough Transform (CHT) and Voting Accumulation for finding the optimal constraint lines. To decrease the operation time, we used logical operations. Optical flow vectors of moving objects are extracted, and the moving information of objects is computed from the extracted optical flow vectors. The simulation results on the noisy test images show that the proposed method finds better flow vectors and more correctly estimates the moving information of objects in the real time video streams.

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Ron Arad의 디자인에 관한 연구 (A Study on the Designs of Ron Arad)

  • 서병기
    • 디자인학연구
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    • 제16권1호
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    • pp.199-208
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    • 2003
  • The Israel-born Ron Arad is one of Britain's "superstar" designers, an it has been said that he is Britain's answer to Philippe Starck. Arad is a highly individualistic designer whose ideas stem from a mental process that has more in common with that of the fine artist than of the jobbing designer for industry. His imagination expresses itself in the form of things. By the early 1990s he had become internationally recognized for his "ready-made" work. His furniture and lighting designs required extremely costly labour-intensive techniques to produce. As his work was highly evocative, suggesting a post-industrial world in which the urban landscape was characterized by materials in a state of decay. More recently, through collaborations with Italian and German manufactures, his work has reached a new level of sophistication and finish, which differentiates it from the earlier designs. As Arad reputation as a designer of workshop-based furniture came to an end and the era of "democratic" Arad furniture came into being. By middle of the decade he had become one of the most-discussed designers of the day. The spirituality that emanates from all his work is a product of his particular vision of the creative process, far removed from the typical, stereotyped trends in the sphere of modern industrialization. He goes one step further in his work by attempting to restore aesthetic dignity to the objects of daily life, in a search for beauty within the immediate environment.hin the immediate environment.

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현대 패션 윈도우 디스플레이에 나타난 키네티시즘 움직임 특성 (Characteristics of Kineticism in contemporary fashion window display)

  • 정예랑;이연희;윤정아
    • 복식문화연구
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    • 제26권3호
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    • pp.327-345
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    • 2018
  • This study analyzes characteristics related to Kineticism found in different kinds of displays and arts in order to contemplate modern window displays. The standard of analysis is based on kinetic arts pioneer George Rickey's six display factors. Projection features and movements were categorized into "Direct movements," "Indirect movements," and "Relative movements." Results were obtained through analysis of different examples of each category. First, the most observed form of Kineticism was direct movements on the window display. Along with the development of science and techniques, a variety of divergent motional methods has arisen. After that followed indirect movement, which uses visual media and lights for presentation. The third was relative movements, which provides communication in practical experience; users' motion is used to provide modification in vision. Fourth, we observed that direct movements and indirect movements can express fluidity depending on materials, inducing a sense of tension within the window display through visual stimuli together with dynamism from mechanical exposure. Fifth, when direct movements pair with relative movements, it triggers customer participation; though it does not deliberately induce participation, the effects are beyond expectation. Sixth, if indirect movements meet relative movements, the motion of lights offers a major stimulation to the customers along with various expressions, thus achieving an interactive domain.

중수형 원자로 급수 배관 검사용 자율 주행형 자벌레 로봇 (Inch-Worm Robot with Automatic Pipe Tracking Capability for the Feeder Pipe Inspection of a PHWR)

  • 최창환;박병석;정현규;정승호
    • 제어로봇시스템학회논문지
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    • 제14권2호
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    • pp.125-132
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    • 2008
  • This paper describes a mobile inspection robot with an automatic pipe tracking system for a feeder pipe inspection in a PHWR. The robot is composed of two inch worm mechanisms. One is for a longitudinal motion along a pipe, and the other is for a rotational motion in a circumferential direction to access all of the outer surfaces of a pipe. The proposed mechanism has a stable gripping capability and is easy to install. An automatic pipe tracking system is proposed based on machine vision techniques to make the mobile robot follow an exact outer circumference of a curved feeder pipe as closely as possible, which is one of the requirements of a thickness measurement system for a feeder pipe. The proposed sensing technique is analyzed to attain its feasibility and to develop a calibration method for an accurate measurement. A mobile robot and control system are developed, and the automatic pipe tracking system is tested in a mockup of a feeder pipe.

A novel hardware design for SIFT generation with reduced memory requirement

  • Kim, Eung Sup;Lee, Hyuk-Jae
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권2호
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    • pp.157-169
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    • 2013
  • Scale Invariant Feature Transform (SIFT) generates image features widely used to match objects in different images. Previous work on hardware-based SIFT implementation requires excessive internal memory and hardware logic [1]. In this paper, a new hardware organization is proposed to implement SIFT with less memory and hardware cost than the previous work. To this end, a parallel Gaussian filter bank is adopted to eliminate the buffers that store intermediate results because parallel operations allow all intermediate results available at the same time. Furthermore, the processing order is changed from the raster-scan order to the block-by-block order so that the line buffer size storing the source image is also reduced. These techniques trade the reduction of memory size with a slight increase of the execution time and external memory bandwidth. As a result, the memory size is reduced by 94.4%. The proposed hardware for SIFT implementation includes the Descriptor generation block, which is omitted in the previous work [1]. The addition of the hardwired descriptor generation improves the computation speed by about 30 times when compared with the previous work.

ASP 서비스의 전략개발방법론에 관한 연구: 기업 네트워크화 사례 (A Study on Methodology for Strategy Development of ASP Service: A Case Study of Small Company Informatization)

  • 홍종의;이윤미;서의호
    • Asia pacific journal of information systems
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    • 제16권3호
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    • pp.177-192
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    • 2006
  • Following the idea of "what you measure is what you get," this paper discusses the necessity to improve the plan and management of Application Service Provider (ASP) service based on performance evaluation. The Balanced Scorecard (BSC) has been used as a tool for suggesting the measures that can evaluate performance of a company by considering both financial and non-financial perspectives. The current BSC does not provide techniques to formally define, verify, implement and analyze the performance measures of ASP. Therefore, we developed a methodology for strategy development of ASP service by analyzing the BSC performance measures. This methodology provides a strategy for improving ASP service. The methodology proposed in this paper provide executives with core parts for achieving vision as well as the corresponding interpretation model for developing strategy. The methodology consists of the following two phases: BSC and Importance-Performance Analysis (IPA) phase. The methodology is illustrated through a case study in each phase. The case study shows practical deployment of our methodology.