• Journal of Mechanical Science and Technology
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• 제17권10호
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• pp.1411-1422
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• 2003

The detection of free spaces between obstacles in a scene is a prerequisite for navigation of a mobile robot. Especially for stereo vision-based navigation, the problem of correspondence between two images is well known to be of crucial importance. This paper describes multi-range approach of area-based stereo matching for grid mapping and visual navigation in uncertain environment. Camera calibration parameters are optimized by evolutionary algorithm for successful stereo matching. To obtain reliable disparity information from both images, stereo images are to be decomposed into three pairs of images with different resolution based on measurement of disparities. The advantage of multi-range approach is that we can get more reliable disparity in each defined range because disparities from high resolution image are used for farther object a while disparities from low resolution images are used for close objects. The reliable disparity map is combined through post-processing for rejecting incorrect disparity information from each disparity map. The real distance from a disparity image is converted into an occupancy grid representation of a mobile robot. We have investigated the possibility of multi-range approach for the detection of obstacles and visual mapping through various experiments.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.116-119
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• 2005

As to the synthetical estimation of land covering parameters or the compounded land covering classification for multi-resolution satellite data, former researches mainly adopted linear or nonlinear regression models to describe the regression relationship of land covering parameters caused by the degradation of spatial resolution, in order to improve the retrieval accuracy of global land covering parameters based on 1;he lower resolution satellite data. However, these methods can't authentically represent the complementary characteristics of spatial resolutions among different satellite data at arithmetic level. To resolve the problem above, a new compounded land covering classification method at arithmetic level for multi-resolution satellite data is proposed in this .paper. Firstly, on the basis of unsupervised clustering analysis of the higher resolution satellite data, the likelihood distribution scatterplot of each cover type is obtained according to multiple-to-single spatial correspondence between the higher and lower resolution satellite data in some local test regions, then Parzen window approach is adopted to derive the real likelihood functions from the scatterplots, and finally the likelihood functions are extended from the local test regions to the full covering area of the lower resolution satellite data and the global covering area of the lower resolution satellite is classified under the maximum likelihood rule. Some experimental results indicate that this proposed compounded method can improve the classification accuracy of large-scale lower resolution satellite data with the support of some local-area higher resolution satellite data.

• 산업공학
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• 제14권3호
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• pp.247-254
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• 2001

As current postal automation is limited to dispatch and arrival sorting, delivery sequence sorting is performed manually by each postman. It not only acts as a bottleneck process in the overall mailing process but is expensive operation. To cope with this problem effectively, delivery sequence sorting automation is required. The important components of delivery sequence sorting automation system are sequence sorter and Hangul OCR which function is to extract the address of delivery point. DSI database will be interfaced to both Hangul OCR and sequence sorter for finding the accurate delivery sequence number and stacker number. The objectives of this research are to develop DSI(Delivery Sequence Information) database prototype and client application for managing information effectively. For database requirements collection and analysis, we draw all possible sorting plans, and apply the AHP(Analytic Hierarchy Process) method to determine the optimal one. And then, we design DSI database schema based on the optimal one and implement it using Oracle RDBMS. In addition, as address information in DIS database consist of hierarchical structure which has its correspondence sequence number, so it is important to reorganize sequence information accurately when address information is inserted, deleted or updated. To increase delivery accuracy, we reflect this point in writing application.

• 한국해안해양공학회지
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• 제5권4호
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• pp.302-306
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• 1993

하수제트플룸내에서 플룸과 주변해수와의 밀도차가 Gauss 분포를 나타내고 있다는 가정하에 하구만에 흘러 나오는 하수 플룸의 횡방향 퍼짐속도의 해석해를 구하였다. 이 가정을 도입하므로써 얻는 이점은 첫째, 혼합과정의 결과가 밀도분포에 반영되어 있으므로 이 문제를 다루는데 있어서 혼합과정에 대한 고려를 할 필요가 없다는 점이고, 둘째로는 밀도분포가 알려져 있으므로 그로부터 압력경사력을 구하여 운동방정식에 대입, 문제를 쉽게 풀 수 있다는 점이다. 이론해를 낙동강 하수플룸의 관측결과와 비교해 본 결과, 비교적 잘 일치함을 발견하였고 본 연구의 이론식이 하수플룸의 퍼짐을 다루는데 유용하게 쓰일 수 있음을 확인하였다.

• 대한의용생체공학회:의공학회지
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• 제20권2호
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• pp.155-164
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• 1999

본 논문에서는 화상 신호처리 및 컴퓨터 그래픽스 요소기술을 이용하여, 컴퓨터 상에서 인공고관절의 시술절차를 적용해 보기 위한 Simulated Implantation System (이하 SIS)을 소개한다 SIS는 일련의 자동화된 절차에 따라, 골반(pelvis)과의 접촉이 이루어지는 대퇴골의 상단부위인 고관절(femoral head)을 대체하는 과정을 3차원적으로 가상 수행할 수 있으며, 환자의 고관절과 인공고관절간의 정합정도를 수치적으로 해석할 수 있는 기능을 궁극적 목표로 하게 된다. 이를 위해 필수적으로 필요한 CT-Image를 이용한 고관절 영상의 3차원 재구성, 그리고 projection image글 이용한 인공고관절의 3차원 표현기법에 대해 논의하고, 각각에 대응되는 결과물들을 분석해봄으로써 현재 의공학 분야에서 절실히 요구되고 있는, 영상신호처리와 컴퓨터그래픽스를 이용한 SIS의 prototype에 대한 모습을 제시해 보고자 한다

• 대한전자공학회논문지SP
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• 제42권3호
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• pp.1-6
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• 2005

변이 영상을 마코브 랜덤필드(MRF)로 모델링한 마코브 네트워크에서 신뢰확산 알고리듬은 각 화소에 대응되는 노드들 사이에 메시지를 전달하는 방식으로 이루어진다. 최초 메시지는 알고리듬의 반복을 통해 특정한 값으로 수렴하게 되며, 수렴된 값을 얻기 위해서는 많은 알고리듬의 반복이 필요하다. 본 논문에서는 알고리듬의 반복을 줄이기 위해 영상내 물체들을 선들의 조합 구성으로 보고 각각의 선들은 같은 메시지를 갖는 노드들의 집합으로 간주하여 기존의 신뢰확산 알고리듬을 단순화하였다.

• 한국가구학회지
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• 제20권2호
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• pp.175-190
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• 2009

As essential element of designers, foundation studies program helps student deal with the individual expression of imagination and variety of correspondence for solving design problem through the understanding of 2-D, 3-D basic design elements, principals, structures. Liberal art and foundation studio courses provides embodiment and settlement of design principal through the foundation studies expand to experiences systematically and deeply. After the Industrialization, foundation studies have developed from Bauhaus in German, the courses have been progressing and systematizing with the demand of time in United States. Growth of Industrialization, expanded design areas departmentalized to various of fields, then the segmentation of foundation courses tend to important than basic design courses. The introduction of information era, the appearance of computer is placed as a tool of design development and added to applied basic courses. This study is intended to know how to change the leading foundation courses in United State due to the revitalization of industrialization and information through the research and analyse to foundation design education curriculums. As a result, most of design school in United States provide drawing, 2-D, 3-D, and 4-D courses included 3-D design element as a basic studies and provide to students introduction to fundamental principal of design concept and communication in both theoretical and applied form. Also though the history, literature, critic, research and survey courses provide students to organize fundamental of systematical logic and understanding design system.

• 한국전기전자재료학회논문지
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• 제21권3호
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• pp.265-271
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• 2008

TCP(Tape Carrier Package), COG (Chip On Glass), COF(Chip On Film) are three methods for connecting LDI(LCD Driver IC) with LCD panels. Especially COF is growing its portion of market place because of low cost and fine pitch correspondence. But COF has a problem of the lead broken failure in LCD module process and the usage of customer. During PCB (Printed Circuit Board) bonding process, the mismatch of the coefficient of thermal expansion between PCB and D-IC makes stress-concentration in COF lead, and also D-IC bending process during module assembly process makes the level of stress in COF lead higher. As an affecting factors of lead-broken failure, the effects of SR(Solder Resister) coating on the COF lead, surface roughness and grain size of COF lead, PI(Polyimide) film thickness, lead width and the ACF(Anisotropic Conductive Film) overlap were studied, The optimization of these affecting manufacturing processes and materials were suggested and verified to prevent the lead-broken failure.

• 한국통신학회논문지
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• 제17권1호
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• pp.80-89
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• 1992

화상처리는 전처리, 중간표현, 최종 인식의 3단계로 구분하여 처리할 수 있다. 본 논문에서는 전처리 단계에서 구해진 에지로 둘러싸인 예영역들로부터 라벨링 기법으로 화상을 구분된 영역의 집합으로 표현한 후 각 영역을 둘러 싸고있는 외측 경계과 내측 경계를 세그먼트화하여 각 세그먼트들에 대한 영역의 정보, 세그먼트 번호, 시작점과 끝점의 정보, 적용된 직선 곡선의 종류 및 이들의 개수 정보 리스트에 대한 데이터 구조를 만드는 중간 표현 단계에 대한 알고리즘을 제안하고, 구해진 데이타 구조를 이용 화상을 재구성한 결과 오차가 한 화소 범위내의 신뢰성이 있음을 확인하였다.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권10호
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• pp.569-574
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• 2003

Computer vision system is broadly adapted like as autonomous vehicle system, product line inspection, etc., because it has merits which can deal with environment flexibly. However, for applying it for that industry, it has to clear the problem that recognize position parameter of itself. So that computer vision system stands in need of camera calibration to solve that. Camera calibration consists of the intrinsic parameter which describe electrical and optical characteristics and the extrinsic parameter which express the pose and the position of camera. And these parameters have to be reorganized as the environment changes. In traditional methods, however, camera calibration was achieved at off-line condition so that estimation of parameters is in need again. In this paper, we propose a method to the calibration of camera using line correspondence in image sequence varied environment. This method complements the corresponding errors of the point corresponding method statistically by the extraction of line. The line corresponding method is strong by varying environment. Experimental results show that the error of parameter estimated is within 1% and those is effective.