• 제목/요약/키워드: Point correspondence

검색결과 138건 처리시간 0.019초

어안렌즈와 천장의 위치인식 마크를 활용한 청소로봇의 자기 위치 인식 기술 (Location Identification Using an Fisheye Lens and Landmarks Placed on Ceiling in a Cleaning Robot)

  • 강태구;이재현;정광오;조덕연;임충혁;김동환
    • 제어로봇시스템학회논문지
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    • 제15권10호
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    • pp.1021-1028
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    • 2009
  • In this paper, a location identification for a cleaning robot using a camera shooting forward a room ceiling which kas three point landmarks is introduced. These three points are made from a laser source which is placed on an auto charger. A fisheye lens covering almost 150 degrees is utilized and the image is transformed to a camera image grabber. The widly shot image has an inevitable distortion even if wide range is coverd. This distortion is flatten using an image warping scheme. Several vision processing techniques such as an intersection extraction erosion, and curve fitting are employed. Next, three point marks are identified and their correspondence is investigated. Through this image processing and image distortion adjustment, a robot location in a wide geometrical coverage is identified.

Range 데이터를 이용한 3-D 물체의 면 인식 방법에 관한 연구 (Identification of Surfaces of a 3-Dimensional Object from Range Data)

  • 박두영
    • 공학논문집
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    • 제2권1호
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    • pp.63-71
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    • 1997
  • 본 논문에서는 range 데이터로부터 평면, 또는 곡면을 갖는 물체의 표면을 인식하여 matching시키는 단순하고 효율적인 방법을 제안한다. 물체의 해당 면을 인식하기 위해 단순히 물체의 면을 나타내는 고유 값만을 비교하기 때문에 인식에 따르는 불필요한 절차를 줄일 수 있다. 여기서, 사용되는 물체의 면을 나타내는 고유값(SRV)은 그 물체의 view-point에 독립적인 특징들에 대하여 가중치를 부여한 값들의 합으로 얻어진다. 따라서, 이 방법은 단순하고 효율적이며 센서에 얻어진 데이터의 잡음과 occlusion에 덜 민감하다.

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상악 중절치간 중심선과 해부학적 부위와의 관계에 대한 조사연구 (A Study on the Various Anatomical Landmarks Associated with Determining the Dental Midline)

  • 김웅철
    • 대한치과기공학회지
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    • 제12권1호
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    • pp.95-102
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    • 1990
  • The distances from the center line between maxillary right and left central incisors(the dental midline) to the various anatomical landmarks were measured. Fifty five students(thirth four males and twenty one females) who have at least natural teeth including maxillary and mandibular incisors and bicuspids were examined. 1. There was statistically significant difference between the dental midline and the center line of maxillary labial frenum(p<0.05). 2. There was no statistically significant difference between the dental midline and the point of incisive papilla, philtrum line, the center line between two mandibular central incisors, and the median palatine suture line(p>0.05). 3. There was no statistically significant sexual difference among data. 4. The philtrum line showed the highest value of correspondence to the center line between two maxillary central incisors followed by the center point of incisive papilla, the center line of two mandibular central incisors, median plaltine suture line and the center line of maxillary labial frenum at the decreasing rate.

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SPECTRAL ANALYSIS FOR THE CLASS OF INTEGRAL OPERATORS ARISING FROM WELL-POSED BOUNDARY VALUE PROBLEMS OF FINITE BEAM DEFLECTION ON ELASTIC FOUNDATION: CHARACTERISTIC EQUATION

  • Choi, Sung Woo
    • 대한수학회보
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    • 제58권1호
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    • pp.71-111
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    • 2021
  • We consider the boundary value problem for the deflection of a finite beam on an elastic foundation subject to vertical loading. We construct a one-to-one correspondence �� from the set of equivalent well-posed two-point boundary conditions to gl(4, ℂ). Using ��, we derive eigenconditions for the integral operator ��M for each well-posed two-point boundary condition represented by M ∈ gl(4, 8, ℂ). Special features of our eigenconditions include; (1) they isolate the effect of the boundary condition M on Spec ��M, (2) they connect Spec ��M to Spec ����,α,k whose structure has been well understood. Using our eigenconditions, we show that, for each nonzero real λ ∉ Spec ����,α,k, there exists a real well-posed boundary condition M such that λ ∈ Spec ��M. This in particular shows that the integral operators ��M, arising from well-posed boundary conditions, may not be positive nor contractive in general, as opposed to ����,α,k.

불완전한 궤적을 고려한 강건한 특징점 추적 알고리즘 (A Robust Algorithm for Tracking Feature Points with Incomplete Trajectories)

  • 정종면;문영식
    • 대한전자공학회논문지SP
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    • 제37권6호
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    • pp.25-37
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    • 2000
  • 특징점의 궤적은 인접한 프레임에 존재하는 특정점 사이의 대응관계로 정의할 수 있다. 실제 영상열에서 존재할 수 있는 잘못된 특징점(false positive, false negative)들은 특징점의 대응관계를 결정할 때 많은 문제를 야기하기 때문에 특징점의 대응관계를 찾는 문제는 어려운 문제로 알려져 있다. 본 논문에서는 새로운 궤적의 나타남, 사라짐 등 불완전한 궤적을 갖는 특징점들을 고려하는 특징점 추적기법을 제안한다. 정합 척도로서 가중치가 부여된 유클리디언 거리를 사용하고 특징점의 운동특성을 잘 반영할 수 있도록 그 가중치를 자동으로 조정한다. 대응점 탐색과정에서 치명적인 영향을 줄 수 있는 애매한 특징점이 존재하는 경우를 고려하여 인접한 프레임 사이의 정합점 결정을 그래프에 의한 최적 대응점 탐색문제로 해결한다. 제안하는 대응점 탐색 알고리즘은 실제 영상열에서 나타날 수 있는 잘못된 특징점들이 대응관계를 결정할 때 주는 영향을 최소화하기 위하여 국부 최적(local optimal)을 찾게되며, 인접한 두 프레임에 m, n개의 특징점이 주어졌을 경우, 최선의 경우 O(mn), 최악의 경우 O($m^2n$)의 계산량을 필요로 한다. 제안하는 알고리즘은 정합과정에서 잘못된 특징점을 고려하고, 특징점의 운동특성을 잘 반영함으로써 대량의 특징점을 추적하는데도 충분히 적용할 수 있음을 실험을 통해 확인하였다.

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Taguchi-RSM 통합모델 제시 (The Development of Taguchi and Response Surface Method Combined Model)

  • 이상복;김연수;윤상운
    • 산업공학
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    • 제23권3호
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    • pp.257-263
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    • 2010
  • Taguchi defined a good quality as 'A correspondence of product characteristic's expected value to the objective value satisfying the minimum variance condition.' For his good quality, he suggested Taguchi Method which is called Robust design which is irrelevant to the effect of these noise factors. Taguchi Method which has many success examples and which is used by many manufacturing industry. But Optimal solution of Taguchi Method is one among the experiments which is not optimal area of experiment point. On the other hand, Response Surface Method (RSM) which has advantage to find optimal solution area experiments points by approximate polynomial regression. But Optimal of RSM is depended on initial point and RSM can not use many factors because of a great many experiment. In this paper, we combine the Taguchi Method and the Response Surface Method with each advantage which is called Taguchi-RSM. Taguchi-RSM has two step, first step to find first solution by Taguchi Method, second step to find optimal solution by RSM with initial point as first step solution. We give example using catapults.

Featured-Based Registration of Terrestrial Laser Scans with Minimum Overlap Using Photogrammetric Data

  • Renaudin, Erwan;Habib, Ayman;Kersting, Ana Paula
    • ETRI Journal
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    • 제33권4호
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    • pp.517-527
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    • 2011
  • Currently, there is a considerable interest in 3D object reconstruction using terrestrial laser scanner (TLS) systems due to their ability to automatically generate a considerable amount of points in a very short time. To fully map an object, multiple scans are captured. The different scans need to be registered with the help of the point cloud in the overlap regions. To guarantee reliable registration, the scans should have large overlap ratio with good geometry for the estimation of the transformation parameters among these scans. The objective of this paper is to propose a registration method that relaxes/eliminates the overlap requirement through the utilization of photogrammetrically reconstructed features. More specifically, a point-based procedure, which utilizes non-conjugate points along corresponding linear features from photogrammetric and TLS data, will be used for the registration. The non-correspondence of the selected points along the linear features is compensated for by artificially modifying their weight matrices. The paper presents experimental results from simulated and real datasets to illustrate the feasibility of the proposed procedure.

머신비젼 기반의 자율주행 차량을 위한 카메라 교정 (Camera Calibration for Machine Vision Based Autonomous Vehicles)

  • 이문규;안택진
    • 제어로봇시스템학회논문지
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    • 제8권9호
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    • pp.803-811
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    • 2002
  • Machine vision systems are usually used to identify traffic lanes and then determine the steering angle of an autonomous vehicle in real time. The steering angle is calculated using a geometric model of various parameters including the orientation, position, and hardware specification of a camera in the machine vision system. To find the accurate values of the parameters, camera calibration is required. This paper presents a new camera-calibration algorithm using known traffic lane features, line thickness and lane width. The camera parameters considered are divided into two groups: Group I (the camera orientation, the uncertainty image scale factor, and the focal length) and Group II(the camera position). First, six control points are extracted from an image of two traffic lines and then eight nonlinear equations are generated based on the points. The least square method is used to find the estimates for the Group I parameters. Finally, values of the Group II parameters are determined using point correspondences between the image and its corresponding real world. Experimental results prove the feasibility of the proposed algorithm.

간호사의 간호역량이 직무만족과 간호업무성과에 미치는 영향 (An Analysis of Nursing Competency affecting on Job Satisfaction and Nursing Performance among Clinical Nurses)

  • 하나선;최정
    • 간호행정학회지
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    • 제16권3호
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    • pp.286-294
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    • 2010
  • Purpose: The purpose of this study was to identify the effects of nursing competency of nurses on job satisfaction and nursing performance. Method: Using a structured questionnaire, data were collected from 368 nurses. Descriptive statistics, t-test, ANOVA, Scheffe test and pearson correlation coefficient with SAS package were used for data analysis. Results: The total mean score for nursing competency was 2.65, with scores for subcategories as follows: ethical competency 2.74, personal competency 2.65, esthetical competency 2.64, and scientific competency 2.61. The mean score of total job satisfaction was 3.18 on a 5 point scale, and nursing performance was 2.97 on a 4 point scale. Total nursing competency and total subcategories of nursing competency perceived by nurses were positively related to job satisfaction and nursing performance. Conclusion: In conclusion, nursing competency of nurses influence job satisfaction and nursing performance. With these result, it is necessary to concentrate on improving nursing competency of nurses to increase job satisfaction and nursing performance.

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

  • 김용식;이홍철;강정윤;남윤석
    • 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.

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