• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.173-176
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• 2002

In this paper, we present the combined 2-D and 3-D algorithms for automatic solder paste inspection. For automatic inspection, optical system for the combined inspection and driving unit is made. One-pass run length algorithm that has fast and efficient memory space is applied to the input image fur extracting solder paste patterns. The path of probe movement is then calculated for an automatic inspection. For a fast 3-D inspection, the phase shift algorithm based on Moire interferometry is also used. In addition, algorithms used in this paper are coded by $MMX^{TM}$. A probe system is manufactured to simultaneously inspect 2-D and 3-D for 10mm$\times$10mm field of view, with resolutions of 10 $\mu\textrm{m}$for both x, y axis and 17 $\mu\textrm{m}$for z axis, and then, experiments on several PCBs are conducted. The processing times of 2-D and 3-D, excluding an image capturing, is 0.039 sec and 0.047 sec, respectively. The credible result with $\pm$ 1$\mu\textrm{m}$uncertainty can be also achieved.

• Journal of radiological science and technology
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• v.41 no.2
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• pp.149-155
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• 2018

Quantitative analysis was performed to confirm that moire artifact was removed without loss of image when using grid suppression software in the diagnosis of micro lesions. we showed that grid suppression images can be morphologically different from original images as they are significantly lower than those of the optimized grid in the similarity analysis with reference images in mammographic phantom images. We were confirmed that images of microcalcification with smaller signal than noise were lost because the pixel values of all lesions increased significantly after the grid suppression, The change in contrast using the NORMI 13 X-ray test phantom was reduced to 30% of the reference image, This result was significantly lower than the 90% when using the optimized grid. In conclusion, the use of grid suppression software in clinical images should be carefully considered because of the possibility of misdiagnosis due to micro lesion loss and morphological changes.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.8
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• pp.1125-1136
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• 2000

Fitness of clothes becomes a major concern in apparel industry. Development of basic patterns will enhance the fitness of clothes. But there are few slacks patterns for the middle-high school girls. So girls had difficulties to buy ready-made clothes of good fit. To solve this problem, it is necessary to develop basic slacks patterns. The purposes of this study was to develop basic slacks patterns based on the analysis of lower body types. 4 girls were selected among 402 anthropometric measurement subjects who are 13 to 15 year-old for the wearing tests. The result of this study can be summarized as follows; 1. Analysing the replicas of lower body surface by using gypsum method, slack patterns were developed. 2. Wearing test by the sensory evaluation showed that the developed slacks pattern was estimated more highly than existing patterns in the items of the comfort of front crotch and back crotch. 3. Wearing test by moire topography method represented that garment silhouette of developed slacks pattern was estimated more highly and garment space of waist, hip were significantly different among patterns.

• Journal of Haehwa Medicine
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• v.20 no.1
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• pp.137-142
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• 2011

Objective : The purpose of this study was to review on the need for early screening of scoliosis. Methods : We have researched and analyzed theories and literatures of scoliosis screening program. Result : The following results were obtained in this study. 1. Scoliosis screening should be carried out to improve middle and high school students's health and learning abilities. 2. The methods are the forward bending test, Moire test and X-Ray. 3. After the examination held by differentiating the degree of scoliosis, surgery or brace treatment for students should be carried out. 4. After the examination, appropriate acupuncture, exercise therapy and orthodontic treatment for students should be carried out. 5. Spinal health courses for young people should be held regularly to equip and encourage a healthy body and healthy mind and contribute to improve the learning efficiency. Conclusion : Scoliosis screening and early detection should be done in the Daejeon city middle school or high school students, and appropriate treatment should be performed as soon as possible.

• Journal of Korea Multimedia Society
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• v.20 no.11
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• pp.1741-1749
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• 2017

In commercial digital-cameras, color-filter filters light according to wavelength range of color filter array (CFA) and the filtered intensities contain color information of light. Then, output data of CFA is transformed to final rendered image through demosaicing process. In image processing of digital-camera, the quality of the final rendered image is affected by optical cross talk of CFA, kind of CFA pattern etc. Basically, pattern of CFA plays important role in image quality of final image rendered by digital-camera. Therefore, an evaluation system capable of quantitatively evaluating CFA is needed. This paper proposes a novel evaluation system using existing and proposed image metrics for evaluating CFAs of digital-camera. Proposed CFA evaluation system consist of color difference in CIELAB and S-CIELAB, Structure SImilarity (SSIM), MTF50, moire starting point (MSP), and subjective preference (SP). MSP and SP are newly designed for the proposed evaluation system. Proposed evaluation system is expressed in polar coordinates to analyze the characteristics of CFA objectively and intuitively. Through simulations, we confirmed that proposed CFA evaluation system can objectively assess performance of developed CFAs.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.5
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• pp.625-634
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• 1986

The strain distribution on a welded aluminum alloy transition joint produced by a static tensile load has been measured using a moire method combined with photoelastic coating method. The test specimens were made of aluminum alloy 6061-T6 and 2014-T6 butt welded with ER-4043 filler metal, and were post welded heat treated (solid solution heat treatment 502.deg. C 70min.) and precipitated (artificial aging 171.deg. C 600min.) to cause an abrupt change of mechanical properties between the base metals and weld metal. The photoelastic epoxy rubber was cemented on the specimen grating which had been reproduced on the specimen surface by using an electropolishing. The measurements were compared with strains computed by Finite Element Analysis. The following results were abtained. (1) The maximum strain were distributed along the center line in the transverse directiion of the weld metal. (2) The strain gradient along the fusion line increased approaching the V-groove tip and the maximum value was observed at a quarter of width from the V-groove tip. (3) The moire method combined with photoelastic coating was proved very useful for real time strain measurement in the welded aluminum alloy transition joint.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.213-225
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• 2009

Objectives : The purpose of this study was to investigate the factors related on pain in female office workers. Methods : Neck pain group of 31 female subjects complained of neck and arm discomfort. Normal group of 20 female subjects had no complaints or minimal discomfort. Cervical curvature and muscle tone were assessed by whole spine x-ray, meridian-electromyography(MEMG), craniovertebral angle, and Moire. Neck pain was evaluated by Neck Disability Index(NDI) and Visual Analog Scale(VAS). The emotional and other physical factors that could effect neck pain were checked by questionnaires including Beck Depression Index(BDI), Stress Reaction Index(SRI), Holmes & Rahe Social Readjustment Rating Scale(SRRS), International Physical Activity Questionnaire(IPAQ), and Gastrointestinal Symptom Rating Scale(GSRS). Results : The contraction and fatigue of upper trapezius by MEMG was significantly higher in the neck pain group. And BDI, SRI, SRRS, and GSRS were significantly higher in the neck pain group (p<0.05). However, there was no significant difference in the Jackson's angle, Cobb's method, craniovertebral angle, and moire between two groups. Conclusions : The results suggest that neck pain is related to mental stress rather than physical stress and physical stress does not change cervical curvature significantly.

• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.117-123
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• 2004

The prediction to the hydroscopic moisture warping behaviors is analyzed for cellulose-based laminates using a numerical method base on a modified classical laminate(MCL) theory for hygroscopic moisture deformations with cycling testing data. The experimental measurement of the interferometric hygroscopic warping effects, moisture generator, and curvature of cellulose reinforced epoxy laminates is studied under cyclic environmental conditions using a Moire interferometer coupled. Accurate determination of curvatures provides a description of dimensional stability evolution; the tools for validation of computational internal stress and for the warpage prediction in model safety.

• Journal of the Korean Society for Precision Engineering
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• v.1 no.3
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• pp.71-84
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• 1984

This paper examined strain distribution and radius of curvature of the bulge by finite element method and investigated limit polar thickness strain to predict the formability of sheet metal as we substituted effective strain and the radius of curvature obtained by FEM into instability condition equation successively. In experiment, the radius of curvature and limit polar thickness strainwere obtained by Moire method. Also, a concent- ric set of photogrid circles was used to measure the strain of arbitrary point and mild steel was used as material. This results obtained are as follows: 1) The radius of curvature obtained by FEM is in good agreement with the Moire experimental value. 2) The polar thickness strain is getting larger as the inside is approached from the edge. This means that fracture occurred near the ploe. 3) The circumferential strains agree closely with the meridian strains and the polar thickness strain is about twice the circumferential (or meridian) strain. This result agrees with the fact that anisotropy coefficient (R-value) obtained by tensile test is about one. 4) The theoretical results of limit polar thickness strain obtained by authors' method are better agreement with experimental results than other theoretical results. Therefore, we can better predict the formability of sheet metal with authors' method.

• Bulletin of the Society of Naval Architects of Korea
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• v.7 no.2
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• pp.27-40
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• 1970

The distribution of stress and strain in elastic stages is investigated by the experiments of two dimensional photoelastic coating and Moire fringe method. Center block type and cover plate type of fillet welds are used as specimens in the test. The results are as follows. 1) Center block type gets less uniform stress distribution than cover plate type. And its stress concentration factor, especially at root, is larger than that at toe. 2) When main plate and cover plate closely contact and it cause friction, stress concentration decreases more than that in case of slit. That is because stress can be transmitted on the contact surface. 3) When slit is made, the outside of fillet gets more stress than the inside of it. 4) While the plastic strain distribution of center block type reaches the maximum at root and differs very slightly from that under lower loading, the plastic strain distribution of cover plate type is inclined to get the maximum at the outside of fillet rather than at root. 5) When the plastic strain value of cover plate type is compared with that of center block type at toe and root, the relations between the former and the latter shows root<toe and root>toe. 6) Because stress distribution becomes changed according to loading, fracture angle cannot be estimated by the peaks of elastic stress distribution. 7) The strain distribution just before fracture can be found by Moire fringe method.