• Journal of Institute of Control, Robotics and Systems
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• v.9 no.12
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• pp.1033-1041
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• 2003

A new visual tracking scheme is proposed for a mobile robot that tracks a moving object in 3D space in real time. Visual tracking is to control a mobile robot to keep a moving target at the center of input image at all time. We made it possible by simplifying the relationship between the 2D image frame captured by a single camera and the 3D workspace frame. To precisely calculate the input vector (orientation and distance) of the mobile robot, the speed vector of the target is determined by eliminating the speed component caused by the camera motion from the speed vector appeared in the input image. The problem of temporary disappearance of the target form the input image is solved by selecting the searching area based on the linear prediction of target motion. The experimental results have shown that the proposed scheme can make a mobile robot successfully follow a moving target in real time.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.5
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• pp.483-488
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• 2008

An active omni-directional raging system using an omni-directional vision with structured light has many advantages compared to the conventional ranging systems: robustness against external illumination noise because of the laser structured light and computational efficiency because of one shot image containing $360^{\circ}$ environment information from the omni-directional vision. The omni-directional range data represents a local distance map at a certain position in the workspace. In this paper, we propose a matching algorithm for the local distance map with the given global map database, thereby to localize a mobile robot in the global workspace. Since the global map database consists of line segments representing edges of environment object in general, the matching algorithm is based on relative position and orientation of line segments in the local map and the global map. The effectiveness of the proposed omni-directional ranging system and the matching are verified through experiments.

• The Journal of Information Systems
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• v.8 no.2
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• pp.49-67
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• 1999

본 연구는 객체지향 기술채택에 영향을 미치는 요인을 조사했다. 한가지의 중요한 연구 의문을 제시했다: 무엇이 객체지향 기술의 채택에 중요하게 영향을 미치는가? 본 연구는 객체지향 기술의 실제 사용정도에 영향을 주는 독립변수를 연구했다. 그 독립변수는 다음과 같은 세 가지 범주로 분류된다: (1) 개인적 요인: 구조지향 방법론을 사용한 경험, 새로운 기술에 대한 개방 정도: (2) 관리적 요인: 경영층의 지원 정도, 훈련, (3) 조직적/환경 요인: 부서와 조직에 있는 정보시스템 전문가의 수, 기술 챔피언에 대한 접근 용이성, 객체지향 기술을 지원하는 소프트웨어 및 하드웨어 환경. 설문지를 이용하여 위에서 언급된 독립변수들이 하나의 독립변수, 즉 객체지향 기술의 실제 사용정도에 미치는 영향을 조사하였다. 그 구조화된 설문지가 미국에 있는 DPMA(Data Processing Management Association)에 소속된 정보시스템 전문가에게 돌려졌다. 본 연구는 기존의 연구 결과와 일치하는 중요한 내용을 보여 주었다. 새로운 기술에 대한 개인의 개방성, 경영층의 지원정도, 훈련, 그리고 하드웨어 및 소프트웨어 환경은 객체지향 기술의 사용과 밀접한 관련이 있었다. 본 연구는 또 조직에서의 객체지향기술의 초기 채택을 이해하는 실증적인 근거를 제시하였다.

• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.159-169
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• 2007

The complex 2-dimensional movements of fish during an annual migration circuit were generated and simulated by a chaotic model of fish movement, which was expanded from a small-scale movement model. Fish migration was modeled as a neural network including stimuli, central decision-making, and output responses as variables. The input stimuli included physical stimuli (temperature, salinity, turbidity, flow), biotic factors (prey, predators, life cycle) and landmarks or navigational aids (sun, moon, weather), values of which were all normalized as ratios. By varying the amplitude and period coefficients of the klinokinesis index using chaotic equations, model results (i.e., spatial orientation patterns of migration through time) were represented as fish feeding, spawning, overwintering, and sheltering. Simulations using this model generated 2-dimesional annual movements of sea bream migration in the southern and western seas of the Korean Peninsula. This model of object-oriented and large-scale fish migration produced complicated and sensitive migratory movements by varying both the klinokinesis coefficients (e.g., the amplitude and period of the physiological month) and the angular variables within chaotic equations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4C
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• pp.400-406
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• 2006

Knowledge of camera parameters, such as position, orientation and focal length, is essential to 3D information recovery or virtual object insertion. This paper analyzes the error sensitivity of focal length due to position error of feature points which are employed for self-calibration. We verify the dependency of the focal length on the distance from the principal point to feature points with simulations, and propose a criterion for feature selection to reduce the error sensitivity.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.675-678
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• 1988

This paper describes the method of syntactic-semantic pattern recognition and description for two dimensional object which is adjusted or changed in size and its orientation. To avoid the complexity and ambiguity which is arised in the case of syntactic or decision-theoretic method is used individually, an attributed grammar is introduced which applies computative attributes to pattern primitives, and then uses decision-theoretic method for attributes and syntactic method for pattern structure. A primitive extraction embedding parsing and grobal rule for classification is also applied for more effective pattern recognition and description.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.604-606
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• 2003

본 논문은 향상된 Scale Invariant Feature Transform (SIFT) 기법과 이로부터 얻어진 로컬 특징 영역에서 다중특징을 이용한 물체인식 방법에 대하여 논하였다. SIFT 기법 [1]은 물체의 크기. 회전. 3차원 좌표변환에 강인한 특성을 갖는다. 이 기법에서는 크기가 다른 가우시안 (Gaussian) 함수를 적용한 영상들의 차이에서의 최대 및 최소값이 특징점으로 결정된다. 하지만 SIFT 알고리듬의 특성상, 인식되어야 될 물체의 비교적 큰 크기 변화, 중요도가 낮은 특징점들의 추출, 그리고 서로 다른 물체에서 추출된 유사한 특징벡터등이 인식 시스템의 신뢰도를 저하 시킬 수 있다. 이에 대응방안으로, 본 논문에서는 상대적으로 낮은 인식정보를 갖는 추출된 특징점을 제거하기 위한 기법과 서로 다른 물체에서 생성된 유사 특징벡터의 구분을 위한 특징점에서의 방위 (orientation) 비교법 및 색차 (chrominance) 정보를 사용에 대하여 기술하였다.

• Journal of the Korean Society for information Management
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• v.9 no.1
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• pp.165-181
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• 1992

The purpose of this study is to review the c-oncept and background of intelligent information system whlch will be fixed on the next generation's information system and to describe the object orientation system. expert system, and hypermedia which are thc core technolclgies in the design of intelligent information system. Furthtmnort., intelligent information systems which are developed using these technologies in the fields of library anti information science, and the future prospect on the intc~lligent information system are described In detail.

• Journal of the Korean Society for information Management
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• v.9 no.1
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• pp.105-105
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• 1992

The purpose of this study is to review the concept and background of intelligent information system which will be fixed on the next generation's information system and to describe the object orientation system. expert system, and hypermedia which are the core technologies in the design of intelligent information system. Furthermore, intelligent information systems information systems which are developed using these technologies system are described in detail.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.743-746
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• 2003

The service robot, with stereo vision system and dual manipulator of four degree of freedom, has been designed. A fuzzy controller has been implemented for effectively actuating the manipulator of the robot. The fuzzy controller determines operation mode(single or dual manipulators) and orientation from the information of object position and distance. Through actual experimentation, we have confirmed that the robot system with human-like movement of grabber has been executed a rapid and effective motion.