• Title/Summary/Keyword: Cross-Points

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Extracting 2D-Mesh from Structured Light Image for Reconstructing 3D Faces (3차원 얼굴 복원을 위한 구조 광 영상에서의 2차원 메쉬 추출)

  • Lee, Duk-Ryong;Oh, Il-Seok
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.248-251
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    • 2007
  • In this paper, we are propose a method to estimate the 2-D mesh from structured light image for reconstruction of 3-D face image. To acquire the structured light image, we are project structured light on the face using the projector. we are extract the projected cross points from the acquire image. The 2-D mesh image is extracted from the position and angle of cross points. In the extraction processing, the error was fixed to extract the correct 2-D mesh.

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Tool interference check in machining of large screws defined by cross-section view (축 수직단면 형상정의에 대한 대형 스크류의 가공시 공구간섭검사)

  • 안중환
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.3
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    • pp.169-177
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    • 2000
  • In machining screws which are important members in mono pumps or progressive cavity pumps CNC turning center with 3 axes is usually used. This sort of screw machining requires large amount of CL data points and rotational tools are used in machining. When working out the CL data points consideration of possible tool interference is important in order to avoid undercut. This paper describes the checking methods of tool interference in the screw machining on the CNC turning center. First of all a specific shape of a screw cross-section that could commonly be applied to all screws was chosen and then possible tool interference associated with that shape was identified. Checking method was mathematically developed and verified. This checking method will be utilized in the CAM system developed by the authors for screw machining on the 3-axis CNC turning center.

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Implementation of a Touch Panel System using Accelerometers (가속도센서를 이용한 터치패널시스템 구현)

  • Lee, Young-Sup;Kim, Dong-Il;Kang, Min-Su
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.12
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    • pp.1194-1202
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    • 2011
  • A touch panel system has been one of the most widely used input devices. In this study, a touch panel embedded system using accelerometers is considered in order to make commercial white-boards or plates into touch panels. Three accelerometers are located at different positions on such a white board, so that touch points on the board can be identified using the sensors. For the identification of touch points, a TDOA (Time Difference of Arrivals) technique is applied in the algorithm which was implemented in a DSP board (TI 6713 DSK), which can provide a precise touch location by using the cross-correlation function of measured signals from the three accelerometers. Experiment results show that the touch panel system with accelerometers could provide the exact touch location. Thus a novel approach using such accelerometers could be applied to a new touch panel system.

An Algorithm for 3-Dimensional Reconstruction of Clinical Ultrasonic Image (임상적 초음파 신호의 3차원 영상처리를 위한 알고리즘)

  • 진영민;우광방;유형식
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.8
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    • pp.658-666
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    • 1989
  • In this paper, an efficient algorithm for estimation volume and surface area and a reconstruction algorithm for 3-dimensional graphics are presented.In order to improve computing efficiency, the graph theory is utilized and the algorithm to obtain proper contour points is developed by considering several tolerances. Search for the contour points is limited by the change of curvature of cross sectional contour to provide efficiency in searching the minimum cost path. In computer simulation of these algorithms, the results show that, for the tolerance values of 1.001 and 1.002, the execution time reduced to 66%-80% and the error for the measured value is less than 3%. The reconstructed 3-dimensional images from the cross sections can be analyzed in many directions using the graphic scheme.

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A Study on the Stifness of Coil Spring in the Three Dimensional Space (3차원 공간에서 코일스프링의 강성에 관한 연구)

  • 이수종
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.5
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    • pp.1130-1139
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    • 2001
  • Springs are widely utilized in machine element. To find out stiffness of coil spring, the space beam theory using the finite element method is adopted in this paper. In three dimensional space, a space frame element is a straight bar of uniform cross section which is capable of resisting axial forces, bending moments about two principal axes in the plane of its cross section and twisting moment about its centroidal axis. The corresponding displacement degrees of freedom are twelve. The displacements of nodal points due to small increment of force are calculated by the finite element method and the calculated nodal displacements are added to coordinates of nodal points. The new stiffness matrix of the system using the new coordinates of nodal points is adopted to calculated the another increments of nodal displacements, that is, the step by step method is used in this paper. The results of the finite element method are fairly well agreed with those of various experiments. Using MATLAB program developed in this paper, spring constants can be predicted by input of few factors.

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A Study on the Stiffness of Frustum-shaped Coil Spring (원추형 코일스프링의 강성에 대한 연구)

  • 김진훈;이수종;이경호
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.11a
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    • pp.21-27
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    • 2001
  • Springs are widely utilized in machine element. To find out stiffness of frustum-shaped coil spring, the space beam theory using the finite element method is adopted in this paper In three dimensional space, a space frame element is a straight bar of uniform cross section which is capable of resisting axial forces, bending moments about two principal axes in the plane of its cross section and twisting moment about its centroidal axis. The corresponding displacement degrees of freedom are twelve. To find out load vector of coil spring subjected to distributed compression, principle of virtual work is adapted The displacements of nodal points due to small increment of force are calculated by the finite element method and the calculated nodal displacements are added to coordinates of nodal points. The new stiffness matrix of the system using the new coordinates of nodal points is adopted to calculate the another increments of nodal displacements, that is, the step by step method is used in this paper. The results of the finite element method are fairly well agreed with those of various experiments. Using MATLAB program developed in this paper, spring constants and stresses can be predicted by input of few factors.

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Automatic Discrete Optimum Design of Space Trusses using Genetic Algorithms (유전자알고리즘에 의한 공간 트러스의 자동 이산화 최적설계)

  • Park, Choon-Wook;Youh, Baeg-Yuh;Kang, Moon-Myung
    • Journal of Korean Association for Spatial Structures
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    • v.1 no.1 s.1
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    • pp.125-134
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    • 2001
  • The objective of this study is the development of size discrete optimum design algorithm which is based on the GAs(genetic algorithms). The algorithm can perform size discrete optimum designs of space trusses. The developed algorithm was implemented in a computer program. For the optimum design, the objective function is the weight of space trusses and the constraints are limite state design codes(1998) and displacements. The basic search method for the optimum design is the GAs. The algorithm is known to be very efficient for the discrete optimization. This study solves the problem by introducing the GAs. The GAs consists of genetic process and evolutionary process. The genetic process selects the next design points based on the survivability of the current design points. The evolutionary process evaluates the survivability of the design points selected from the genetic process. In the genetic process of the simple GAs, there are three basic operators: reproduction, cross-over, and mutation operators. The efficiency and validity of the developed discrete optimum design algorithm was verified by applying GAs to optimum design examples.

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Development of the Evaluation Indicators of Positive Nursing Organizational Culture in a Clinical Setting (임상현장에서의 긍정적인 간호조직문화 평가지표 개발)

  • Yom, Young Hee;Noh, Sang Mi;Kim, Kyung Hee;Ji, Soon Ju;Kim, Hyun Jung
    • Journal of Korean Clinical Nursing Research
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    • v.19 no.2
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    • pp.233-244
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    • 2013
  • Purpose: The purpose of this study was to develop the evaluation indicators of positive nursing organizational culture in a clinical setting. Methods: The evaluation indicators of positive nursing organizational culture were developed from a literature review and a focus group interview. The content validity testing was done using a clinical expert panel. The content utility testing was done using a survey questionnaire. Results: The evaluation indicators of positive nursing organizational culture consists of 88 indicators representing the eight domains with the 24 categories. The average scores in evaluation indicators of positive nursing culture included the importance (3.29 points in average), the potential for further utilization (3.14 points in average) and the current state of extension agency (2.80 points in average). Conclusion: The developed evaluation indicators can be applied to measure the nursing organizational culture, which would be the basic data to manage human resources effectively in a clinical setting.

Digital Watermarking Technique for Images with Perspective Distortion

  • Chotikakamthorn, Nopporn;Yawai, Wiyada
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1090-1093
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    • 2004
  • In this paper, a problem of geometrically distorted images is considered. In particular, the paper discusses the detection of a watermark from a photographed image of the watermarked picture. The image is possibly obtained by using a digital camera. This watermark detection problem is made difficult by various geometric distortions added to the original picture through the printing and photographing processes. In particular, the paper focuses on the geometric distortion due to a projective transformation, as part of a camera 3D-to-2D imaging process. It is well-known that a cross ratio of collinear points is invariant under a perspective projection. By exploiting this fact, a projective-invariant digital watermarking technique is developed. By detecting the picture's corners, and the image center point at the intersection of two main diagonal lines, predefined cross ratios are used to compute the watermark embedded locations. From those identified embedding pixel locations, a watermark can be detected by performing a correlation between a watermark pattern and the image over those pixels. The proposed method does not require an inverse transformation on the distorted image, thus simplifying the detection process. Performance of the proposed method has been analyzed through computer experiments

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Research on Cognition of Infection Control by Dental Hygienics Student's in some Areas (일부 지역 치위생학과 학생들의 감염방지에 관한 인식 조사)

  • Moon, Seon-Jeong;Ku, In-Young
    • The Journal of the Korea Contents Association
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    • v.12 no.12
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    • pp.313-320
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    • 2012
  • A dental treatment room is always exposed to diverse kinds of pathogenic bacteria, and may be a mediating place of cross-infection given being contaminated the interior of a room through several routes in the form of patient's secretion and aerosol. The main agent of preventing cross-infection is a dental hygienist in the dental treatment and the dental treatment room where are scattered about a risk of cross-infection. A dental hygienist needs to have right recognition on infection control before being active as a clinical expert. This infection-control recognition level is influenced from the clinical practice. Accordingly, to survey recognition of infection control, a self-administered questionnaire research was conducted targeting 314 students who are fixed the clinical practice as regular subject in the junior course out of curriculum for the Department of Dental Hygiene at some of 4-year universities. Data collection was performed from December 9, 2011 to February 22, 2012. Except 11 copies of questionnaire with insincere response among the collected materials, 303 copies were finally analyzed by using SPSS WIN 20.0. The following conclusions were obtained. In the infection disease section, both on and off campus showed 4.89 points from 'the importance of recognizing the infections prevention', 4.65 points from 'recognizing the compulsory preventative injection for hepatitis type B', 4.77 points from 'recognizing the necessity of the preventative injection for hepatitis type B', 4.71 points from 'whether practice the prevention in reality or not', and 4.76 points from 'the educational helps to the prevention'. In other words, the section recorded the highest and meaningful points. It is considered to be needed the development in systematic and diverse infection-control educational programs and the differentiated education depending on school year for dental hygiene students.