• Title/Summary/Keyword: Correspondence Problem

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Multi-Range Approach of Stereo Vision for Mobile Robot Navigation in Uncertain Environments

  • Park, Kwang-Ho;Kim, Hyung-O;Baek, Moon-Yeol;Kee, Chang-Doo
    • Journal of Mechanical Science and Technology
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    • v.17 no.10
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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.

COMPOUNDED METHOD FOR LAND COVERING CLASSIFICATION BASED ON MULTI-RESOLUTION SATELLITE DATA

  • HE WENJU;QIN HUA;SUN WEIDONG
    • Proceedings of the KSRS Conference
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    • 2005.10a
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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.

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Development of DSI(Delivery Sequence Information) Database Prototype (순로정보 데이터베이스 프로토타입 개발)

  • Kim, Yong-Sik;Lee, Hong-Chul;Kang, Jung-Yun;Nam, Yoon-Seok
    • IE interfaces
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    • v.14 no.3
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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.

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A Hydrodynamic Solution for the Lateral Spreading of a River Plume (하천수 플룸 횡방향 퍼짐의 해석해)

  • Yu, Hong-Sun;Lee, Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.5 no.4
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    • pp.302-306
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    • 1993
  • Assuming Gaussian distribution of the density difference between a turbulent jet river plume and its ambient saline water, a hydrodynamic solution for the lateral spreading of a river plume is developed. Two advantages can be expected from the assumption we made. Firstly, we need not consider mixing processes in the plume in dealing with this Problem. Secondly, by Putting pressure gradients which can be obtained from the density distribution, into the equation of motion, we can solve them easily. We compared the analytic solution with the fold data of the Nakdong river plume and found reasonably good correspondence.

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A Study on 3d Reconstruction and Simulated Implantation of Human Femur Using Consecutive CT-Images (연속된 CT-Image를 이용한 고관절 3d 형상의 재구성 및 Simulated Implantation System 구축에 관한 연구)

  • 민경준;김중규;최재봉;최귀원
    • Journal of Biomedical Engineering Research
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    • v.20 no.2
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    • pp.155-164
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    • 1999
  • In this paper, the prototype of SIS(Simulated Implantation System) for human femoral head is introduced. SIS is a software which carries on a virtual femoral head replacement surgery including 3d visualization as well as various numeric analyses between a patient's femur and artificial femur through certain stages of the image processing and of the computer graphics. Also, processes required after acquiring consecutive CT-images and projected image of an artificial femur are discussed, and the corresponding results including prototype of SIS are given.

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Stereo Matching using Belief Propagation with Line Grouping (신뢰확산 알고리듬을 이용한 선 그룹화 기반 스테레오 정합)

  • Kim Bong-Gyum;Eem Jae-Kwon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.3 s.303
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    • pp.1-6
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    • 2005
  • In the Markov network which models disparity map with the Markov Random Fields(MRF), the belief propagation algorithm is operated by message passing between nodes corresponding to each pixel. The initial message value is converged by iterations of the algorithm and the algorithm requires many iterations to get converged messages. In this paper, we simplify the algorithm by regarding the objects in the disparity map as combinations of lines with same message valued nodes to reduce iterations of the algorithm.

A Study on The Foundation Corse of Design Schools in USA (미국 디자인대학의 Foundation과정에 관한 연구)

  • Min, Chan-Hong
    • Journal of the Korea Furniture Society
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    • v.20 no.2
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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.

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Improvement of COF Bending-induced Lead Broken Failure in LCD Module (LCD Module내 COF Bending에 따른 Lead Broken Failure의 개선)

  • Shim, Boum-Joo;Choi, Yeol;Yi, Jun-Sin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.3
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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.

Data Structure Extraction of Boundary Segments by Region Labeling (영역 라벨링에 의한 경계선 세그먼트의 데이터 구조 추출)

  • 최환언;정광웅;김두영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.1
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    • pp.80-89
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    • 1992
  • This paper presents algorithms which are region labeling and data structure of a boundary segmentation as image intermediate description process. In the method, the algorithms are region labeling, boundary segmentation, line and curve fitting and extracting data structure of each segment. As a result, a data structure of image is described by a set of region number, segment number, line or curve, starting point and end point of each segment and coefficient of line or curve. These data structures would serve for higher level processing as object recognition. For example we will use this data structure to solve the correspondence problem of stereoscopic image information. And we verified these algorithms through the image reconstruction of data structure.

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Estimation of Camera Calibration Parameters using Line Corresponding Method (선 대응 기법을 이용한 카메라 교정파라미터 추정)

  • 최성구;고현민;노도환
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.10
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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.