• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.118-122
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• 1997

This paper presents a 3d image processing which uses neural networks to combine a 2D vision camera and a laser slit beam. A laser slit beam from laser source is slitted by a set of cylindrical lenses and the line image of the slit beam on the object is used to estimate the object parameters. The neural networks allow to get the 3D image parameters such as the size, the position and the orientation form the line image without knowing the camera intrinsic parameters.

• 공학논문집
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• 제3권1호
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• pp.117-121
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• 1998

본 논문에서는 실시간 프로그래밍 언어와 적절히 연동할 수 있는 자원관리 모델을 제시한다. 시스템의 자원을 계층적으로 관리하여 일관된 인터페이스 환경을 유지하면서 미세조정까지 가능한 자원 이용환경을 제공하고자 하는 것이다. 이와 같은 객체지향 자원관리 기법은 계산 시간 부족을 처리하는 근사값 접근방법의 효과를 더욱 상승시킬 것이며, 또한 동적 실시간 시스템을 구축함도 용이롭게 할 수 있을 것이다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1997년도 춘계학술대회 학술발표 논문집
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• pp.259-262
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• 1997

This paper presents a visual servoing of RV-M2 robot manipulators to track and grasp moving object, using pruned dynamic recurrent neural networks(DRNN). The object is stationary in the robot work space and the robot is tracking and grasping the object by using CCD camera mounted on the end-effector. In order to optimize the structure of DRNN, we decide the node whether delete or add, by mutation probability, first in case of delete node, the node which have minimum sum of input weight is actually deleted, and then in case of add node, the weight is connected according to the number of case which added node can reach the other nodes. Using evolutionary programming(EP) that search the struture and weight of the DRNN, and evolution strategies(ES) which train the weight of neuron, we pruned the net structure of DRNN. We applied the DRNN to the Visual Servoing of a robot manipulators to control position and orientation of end-effector, and the validity and effectiveness of the pro osed control scheme will be verified by computer simulations.

• International Journal of Naval Architecture and Ocean Engineering
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• 제1권2호
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• pp.89-94
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• 2009

The current focus of development in industrial Computational Fluid Dynamics (CFD) is integration of CFD into Computer-Aided product development, geometrical optimisation, robust design and similar. On the other hand, in CFD research aims to extend the boundaries of practical engineering use in "non-traditional" areas. Requirements of computational flexibility and code integration are contradictory: a change of coding paradigm, with object orientation, library components, equation mimicking is proposed as a way forward. This paper describes OpenFOAM, a C++ object oriented library for Computational Continuum Mechanics (CCM) developed by the author. Efficient and flexible implementation of complex physical models is achieved by mimicking the form of partial differential equation in software, with code functionality provided in library form. Open Source deployment and development model allows the user to achieve desired versatility in physical modeling without the sacrifice of complex geometry support and execution efficiency.

• 한국정밀공학회지
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• 제10권4호
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• pp.248-254
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• 1993

This paper proposes the labeling method for solving bin-picking problem in robot vision. It has the processing steps such as image thresholding, region labeling, and moment computation. To determine a target object from object, the modified labeling method is used to. The moment concept applied to determine the position and orientation of target object. Finally, some experiment result are illustrated and compared with the results of conventional shrinking algorithm and collision fronts algorithm. The proposed labeling method has reduced processing time.

• 한국생산제조학회지
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• 제8권6호
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• pp.26-34
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• 1999

This study shows an alternative method for the determination of object's position, based on a computer vision method. This approach develops the vision system model to define the reciprocal relationship between the 3-D real space and 2-D image plane. The developed model involves the bilinear six-view parameters, which is estimated using the relationship between the camera space location and real coordinates of known position. Based on estimated parameters in independent cameras, the position of unknown object is accomplished using a sequential estimation scheme that permits data of unknown points in each of the 2-D image plane of cameras. This vision control methods the robust and reliable, which overcomes the difficulties of the conventional research such as precise calibration of the vision sensor, exact kinematic modeling of the robot, and correct knowledge of the relative positions and orientation of the robot and CCD camera. Finally, the developed vision control method is tested experimentally by performing determination of object position in the space using computer vision system. These results show the presented method is precise and compatible.

• 한국조경학회지
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• 제27권4호
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• pp.59-64
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• 1999

This study is about gaining orientation through anchorage act of a group of ferryman. In addition, a point acquisition and character of landmark that is closely realated to a point acquisition would be clarified by studying the form of configuration of the earth and object which is used landmark for anchorage. There are 13 anchorage points in the north part of Pusan harbor. 12 anchorage points are used to anchor. A ferryman let a ship which is temporarily anchoring move safely and speedily at the anchorage point. At that time, he uses landmarks by a technique of Overlay View. Between landmarks and viewer would be formed exquisite location combination. A mountain peak, a peak of island, nature configuration of land such as intermitent rock and location, size and form of buildings or structures of a city were variously appeared as landscape elements which were used landmarks. Looking at conditions to be easily captured as a target object, 1. A particular point of a mountain ridge line which was not shield by buildings. 2. In case objects have similar form, the building which was located in the front or the highest. 3. In case of a singular object, whatever there is physical elements, that would be a target object. Through this study a configuration of the ground such as a mountain peak which is become the background of harbor landscape is very important element to find anchorage point in configuration of the ground and object. So, the continuous preservation of the contour line of mountain is needed to do safe and effective anchorage act.

• Journal of Mechanical Science and Technology
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• 제17권10호
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• pp.1431-1442
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• 2003

A new method of estimating the pose of a mobile-task robot is developed based upon an active calibration scheme. The utility of a mobile-task robot is widely recognized, which is formed by the serial connection of a mobile robot and a task robot. To be an efficient and precise mobile-task robot, the control uncertainties in the mobile robot should be resolved. Unless the mobile robot provides an accurate and stable base, the task robot cannot perform various tasks. For the control of the mobile robot, an absolute position sensor is necessary. However, on account of rolling and slippage of wheels on the ground, there does not exist any reliable position sensor for the mobile robot. This paper proposes an active calibration scheme to estimate the pose of a mobile robot that carries a task robot on the top. The active calibration scheme is to estimate a pose of the mobile robot using the relative position/orientation to a known object whose location, size, and shape are known a priori. For this calibration, a camera is attached on the top of the task robot to capture the images of the objects. These images are used to estimate the pose of the camera itself with respect to the known objects. Through the homogeneous transformation, the absolute position/orientation of the camera is calculated and propagated to get the pose of a mobile robot. Two types of objects are used here as samples of work-pieces: a polygonal and a cylindrical object. With these two samples, the proposed active calibration scheme is verified experimentally.

• Spatial Information Research
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• 제13권2호
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• pp.129-138
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• 2005

본 논문에서는 스테레오 CCD 카메라를 이용하여 이동체의 3차원 위치좌표를 추출하는 알고리즘을 제안하였다. 이 알고리즘을 통해 효율적으로 이동체의 3차원 위치좌표를 추출하는 방법을 도출하고자 하였다 스테레오 CCD 카메라의 상호표정을 수행하고, 획득된 영상에서 이동체를 배경과 분리한 뒤, 좌$\cdot$우 영상에서 이동체의 영상좌표를 추출한다. 추출된 좌$\cdot$우 영상에서의 영상좌표를 이용하여 이동체의 3차원 위치를 결정하게 된다. 스테레오 CCD 카메라간의 상호 위치 및 자세를 결정하기 위한 표정 모듈은 독립적 상호표정(independent relative orientation)을 사용하였고, 획득된 영상에서 이동체 추출 알고리즘은 칼라영상의 RGB(Red, Green, Blue) 화소값을 이용하여 구현하였다. 좌$\cdot$우 CCD 카메라로부터 들어오는 영상좌표를 이용하여 공간전방교회 법을 통해 이동체의 위치를 계산하였다. 그리고 전체 시스템의 실험을 수행하였고, 그 결과의 정확도를 비교하였다.

• 한국안전학회지
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• 제17권3호
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• pp.7-12
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• 2002

The object of this paper is to investigate collapse characteristics of CF/Epoxy(Carbon Fiber/Epoxy resin) composite tubes on the change of interlaminar number and fiber orientation angle of outer and to evaluate reappearance of collapse characteristics on the change of tension strength of fibers under static and impact axial compression loads. When a CF/Epoxy composite tube is mushed, static/impact energy is consumed by friction between the loading plate and the splayed fiends of the tube, by fracture of the fibers, matrix and their interface. In general, CF/Epoxy tube with 6 interlaminar number(C-type) absorbed more energy than other tubes(A, B, D-types). The maximum collapse load seemed to increase as the interlaminar number of such tubes increases. The collapse mode depended upon orientation angle of outer of CF/Epoxy tubes and loading status(static/impact). Typical collapse modes of CF/Epoxy tubes are wedge collapse mode, splaying collapse mode and fragmentation collapse mode. The wedge collapse mode was shorn in case of CF/Epoxy tubes with 0$^{\circ}$ orientation angle of outer under static and impact loadings. The splaying collapse mode was shown in only case of CF/Epoxy tubes with 90$^{\circ}$ orientation angie or outer under static loadings, however in impact tests those were collapsed in fragmentation mode. So that CF/Epoxy tube with 6 interlaminar number and 90$^{\circ}$ outer orientation angle presented to the optimal collapse characteristics.