• Title/Summary/Keyword: moire

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Spinal Deformity Detection Based on the Evaluation of Middle Line´s Displacement on a Moire Image of a Human Back

  • Kim, Hyoungseop;Seiji Ishikawa;Yoshinori Otsuka;Hisashi Shimizu;Takashi Shinomiya
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.105.1-105
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    • 2001
  • In this paper, a technique is described for classifying normal cases and abnormal cases in automatic spinal deformity detection by computer based on moire topographic images of human backs. Displacement is evaluated statistically between the middle line extracted from the entire moire image and the middle line obtained from a small rectangle area defined on the moire image. The middle line is calculated employing a developed potential symmetry analysis technique. The displacement is calculated in several regions and the mean and the standard deviation of the displacement values are chosen as two features. A linear discriminant function (LDF) is defined on the 2-D feature space based on the Mahalanobis distance and the features are classified into two categories, i.e., normal and ...

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Thermo-mechanical and Flexural Analysis of WB-PBGA Package Using Moire Interferometry (무아레 간섭계를 이용한 WB-PBGA 패키지의 온도변화 및 굽힘하중에 대한 거동해석)

  • Han, Bong-Tae;Joo, Jin-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.7
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    • pp.1302-1308
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    • 2002
  • Thermo-mechanical and flexural behavior of a wire-bond plastic ball grid array (WB-PBGA) package are characterized by high sensitive moire interferometry. Moire fringe patterns are recorded and analyzed for several bending loads and temperatures. At the temperature higher than $100^{\circ}C$, the inelastic deformation in solder balls become more dominant, so that the bending of the molding compound decreases while temperature increases. The deformation caused by thermally induced bending is compared with that caused by mechanical bending. The strain results show that the solder ball located at the edge of the chip has largest shear strain by the thermal load while the maximum average shear strain by the bending moment occurs in the end solder.

Evaluation of Thermal Deformation Model for BGA Packages Using Moire Interferometry

  • Joo, Jinwon;Cho, Seungmin
    • Journal of Mechanical Science and Technology
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    • v.18 no.2
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    • pp.230-239
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    • 2004
  • A compact model approach of a network of spring elements for elastic loading is presented for the thermal deformation analysis of BGA package assembly. High-sensitivity moire interferometry is applied to evaluate and calibrated the model quantitatively. Two ball grid array (BGA) package assemblies are employed for moire experiments. For a package assembly with a small global bending, the spring model can predict the boundary conditions of the critical solder ball excellently well. For a package assembly with a large global bending, however, the relative displacements determined by spring model agree well with that by experiment after accounting for the rigid-body rotation. The shear strain results of the FEM with the input from the calibrated compact spring model agree reasonably well with the experimental data. The results imply that the combined approach of the compact spring model and the local FE analysis is an effective way to predict strains and stresses and to determine solder damage of the critical solder ball.

The Characteristics of the Moire Topography in Patients of HIVD of Cx-spine (경추 추간판 탈출증 환자의 경근무늬 측정상의 특징)

  • Park, Jung-Hyuk;Yoo, Han-Gil
    • The Journal of Korea CHUNA Manual Medicine
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    • v.6 no.1
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    • pp.21-30
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    • 2005
  • Objectives : This study was designed to find The characteristics of the Moire topography in patients of HIVD of Cx-spine. Methods : The Moire topography using IBS(Intek-plus Body Scanner 2000, Seoul, Korea) were obtained in 688 people of control group and 105 patients of HIVD of Cx-spine. Each values were studied to determine the difference between controls and patients. Results : There were significantly difference between controls and patients in thoracic ratio, lumbar ratio, top of the thoracic depth ratio, top of the lumbar depth ratio, Z axis distance and DZ/DY. Conclusions : There were increase of the thoracic kyphosis and lower position in top of the thoracic kyphosis in patients of HIVD of Cx-spine than controls.

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East 3-Dimensional Shape Reconstruction Using Phase-Shifting Grating Projection Moire Method (위상천이 영사식 모아레법을 이용한 고속 3차원 형상복원)

  • 최이배;구본기;정연구
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1998.11a
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    • pp.111-115
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    • 1998
  • A phase-shifting projection moire method particularly intended for high-speed three-dimensional shape reconstruction of diffuse objects is presented. Emphasis is on realization of phase-shifting fringe analysis in projection moire topography using a set of line grating pairs designed to provide different phase shifts in sequence. Further a time-integral fringe capturing scheme is devised to remove undesirable high frequency original grating patterns in real-time without time-consuming software image processing. Finally the performances of the proposed method are discussed with measurement results.

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A Study on 3-D Shape Measurement and Application by Using Digital Projection Moire (II) (디지털 영사식 무아레를 이용한 3차원 형상 측정과 응용에 관한 연구(II))

  • Ryu, Weon-Jae;Kang, Young-June;Rho, Hyung-Min;Lee, Dong-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.5
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    • pp.62-67
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    • 2007
  • A simple dimension measuring method for the measurement of human bust has been developed using projection moire. The 3-D data of a human bust was calculated from the 2dimensional image information obtained by the stripe using projection moire. The creation of 3-D geometric shape by digitizing real objects has been widely investigated in reverse engineering(RE). This procedure generally consists of three basic steps: data capture, data alignment and model reconstruction. In order to achieve a complete model, multiple scans must be taken and aligned.

A Study on the Strain Analysis by Image Processing Technique (화상처리기법을 이용한 변형율해석에 관한 연구)

  • 백인환;신문교
    • Journal of Advanced Marine Engineering and Technology
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    • v.12 no.4
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    • pp.32-45
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    • 1988
  • The scanning moire method, in which the master grating is replaced by the scanning line of television camera and in which the moire pattern is obtained by thining out some scanning line, is discussed by the sampling theory. It is determined also by the sampling theory that relationship between the fringe pattern. The programs that analyze the strain by the scanning moire method have been developed. For the simulation model in which we are able to calculate analytically the distribution of strains, the scanning moire method is discussed. It is shown that the small strains and the large strains are analyzed from the same picture by the thinning out technique and that the accuracy of analysis is improved by change of the phase in the thinning out technique.

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A Study on the Improvement of Accuracy of Shape Measurement in the Shadow Moire Method (그림자식 모아레를 이용한 형상측정법의 정확도 개선에 관한 연구)

  • 박경근;박윤창;정경민
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.05a
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    • pp.175-180
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    • 1999
  • Generally, When we measure of object 3D surfaces with phase shifting shadow moire method, it is use of optical system consist of light source, grating, and ccd camera. At this time, it is important parameter that vertical distance of grating and camera, grating and light source, and horizontal distance of camera and light source. When use camera consist of complex lens vertical distance of grating and camera is unknown parameter. From this cause equivalent wave length of moire fringe is uncertain. In this study, We exactly obtain a vertical distance of grating and camera so improve on measurement accuracy.

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A Study on the measurement of 3-D Object with Single Grating Shiftings (단일격자 이송을 이용한 영사식 3차원 물체 형상 측정에 관한 연구)

  • 박윤창;정경민
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.05a
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    • pp.187-192
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    • 1999
  • Noncontact measuring methodology of 3-dimensional profile using CCD camera are very attractive because of it's high measuring speed and its's high sensitivity. Especially when projecting a grid pattern over the object, the captured image have 3 dimensional information of the object. Projection moire extract 3-D information with another grid pattern in front of CCD camera. However phase measuring profilometry(PMP) obtain similar results without additional grid pattern. In this paper, the projection moire are compared with the PMP mathematically, and it is shown that PMP can generate moire image with simple mathematical computations. Experimental works are also carried out showing the same results. It is shown that using a single gird pattern, moire image can be obtained directly without any mathematical operation when some conditions are satisfied.

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A Study on the Measurement of the Breast Shape on Living Body by Using a PMP Moire Method (가슴형상 측정을 위한 PMP Moire 방법 활용)

  • Lee, Ga-Na;Yuk, Keun-Cheol;Kim, Byeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.11 no.2
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    • pp.11-21
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    • 2009
  • Recently, as custom-made demand about female underwear is increased, securing of a various dimension system is urgent, and satisfaction of each customer cannot be heightened with established dimensions. If we could measure shape of a living body with a fast and simple method, the custom-made demand of customers could be satisfied in the underwear as well as a clothing industry by using the method. One of the alternatives is shape measurement of the living body by a Moire fringe method. If we put a grating in front of an object to be measured and illuminate light, a Moire fringe with contour line shape is generated in the object, so we can conveniently measure object shape without touching directly by using the pattern. The Moire fringe and three-dimensional shape of the breast of the living body was acquired by a PMP method using a polygon mirror, and height and bottom width of the breast of the living body were measured by using obtained data in this study. Data of breast shape measurement through a mannequin was collected in a previous step as basic material for measuring the breast shape measurement of the living body. Three women in the twenties were selected as one of methods for measuring breast shape of a woman. As a result of the breast shape measurement of a living body A, it was measured that height of the breast was about 67.24mm and the bottom width was $13781.60mm^2$. This study is expected to contribute for collecting basic data of a female underwear industry and establishing a specification of a dimension system.

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