• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.208-211
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• 2005

The volumetric interferometer, which uses the interference of wavefronts emitted from two single mode fibers, measures the target position in 3-D. In this paper, we suggest a new calculation method which doesn't need a non-linear optimization and an initial guess. We find the relationship between the coefficients of the Zernike polynomials for a spherical wavefront and its center and reconstruct a spherical wavefront by using the Zernike polynomials from two interference fringes like a lateral shearing interferometer. The target position can be obtained from the coefficients of the Zernike polynomials of the reconstructed wavefront. We can get the target position in 3-D with $sub-{\mu}m$ errors in a simulation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.772-776
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• 2004

The paper describes the quantitative determination of out-of-plane displacement from result of Shearogrpahy, which can measure the first-order partial derivative of out-of-plane displacement directly. However, the differential sensitivity of Shearography is related to the amount of shearing, which is manually adjustable in optical interferometer and affects the quantitative determination. The relationship between those is inspected by comparing ESPI with Shearography. From the result, the amount of shearing plays a modulation factor of out-of-plane displacement and small amount of shearing gives good agreement with out-of-plane displacement.

• 소성∙가공
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• 제32권2호
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• pp.61-66
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• 2023

The quality of the sheared surface affects the stretch flangeability of steel sheet. The quality of sheared surface is influenced by several process factors such as die clearance, shape of cutting edge, use of counter punch, and shear. In this paper, the influence of these shearing process factors on the stretch flangeability of the HSS (DP980) was analyzed through a shearing and a stretch flangeability test. When the die clearance was 10%, the effect of these shearing process factors on the stretch flangeability was the greatest, and the use of an acute angle blade was found to be more advantageous in the stretch flangeability than a right angle blade. It was found that the stretch flangeability was improved when active bending was applied during shearing.

• 한국지반공학회논문집
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• 제18권5호
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• pp.73-81
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• 2002

최근에 FRP보강 그라우팅 공법이라 불리는 보강공법이 터널 및 절취사면의 지반보갓 분야에 도입되어 적용이 확대되고 있다. FRP관은 부식 및 화학적 내성이 우수하고 무게에 비하여 강도가 우수하여 취급이 용이하여 기존의 터널 보강재인 강재의 좋은 대체품이 될 수 있다. 그러나 FRP관이 터널의 막장 및 천단부의 보강재로서 적용성을 입증하기 위해서는 보강재 및 보강지반에 대한 역학적 강도특성이 명확하게 평가되어야 한다. 따라서, 본 논문은 지반보강 메카니즘을 고려한 FRP관을 이용한 그라우트체 및 그라우팅 보강지반에 대한 전단특성을 평가하기 위하여 실내에서 그라우트체에 대한 양면 전단시험과 보강지반에 대한 직접전단시험을 실시하였다. 시험결과 FRP 그라우트 보강지반의 전단저항은FRP관의 전단강도에 크게 의존하며 FRP그라우트체의 자체 전단저항은 어느 정도 전단변위가 커진 후에 발휘되는 것으로 확인되었다.

• 한국의류산업학회지
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• 제2권2호
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• pp.150-158
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• 2000

This study investigated mechanical properties, drape coefficients and node indices of stretch fabrics. We applied mechanical properties to exhibited tailorability control in HESC and evaluated making-up. The mechanical properties such as tensile, bending, shearing, compression, surface characteristic values, thickness and weight were measured by the KES-F system and drape coefficient by drape tester. The summarized results of this study were as follows; First, stretch fabrics, almost, shown high stretch in weft inserted polyurethane yarn fabric and had a ${\pm}2{\sigma}$(sigma) range of shearing, compression, surface and thickness, except bending and weight, as compared with Japanese women's thin dress fabrics. Second, bending had a positive correlation in stiffness, anti-drape and flexibility & softness. Shearing had a negative correlation in crispness and scroop. Surface properties had a high contribution in fullness & softness. Third, The drape coefficient was found by measuring the mechanical properties according to the obtained regression equation. Forth, many problems are expected in overfeed and cutting operations in sewing process. In the decision of the good external appearance using TVA, only 26 of 55 samples are included in the range of the good external appearance. Fifth, in the regard of the result for sewing control, warp values are not necessary to control in the all kind of items. But weft value in the RT and EM are out of non-control zone. So we need a special management during sewing process.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.426-430
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• 2008

Hot shear-welding is a process of bonding two plates together by using shearing stress in a controlled manner. This study dealt with the hot shear-welding process of two aluminum plates. These two plates were piles up in the shear-welding mold. Due to the shearing stress, these two plates were cut off longitudinally, and meantime they were welded together. During this process the control of the surplus material flow is very important, and it can be realized by designing the overlapping length and the shape of the cavity. The commercial software Deform-3D was employed to predict the effect of these two factors. The overlapping length and the shape of the cavity that presents the optimum design was then developed to get a good shear-welding process.

• 한국의류산업학회지
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• 제6권4호
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• pp.497-502
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• 2004

The mechanical properties of jean slacks to the type of cutting lines in knee region and the bending time, after doing bending 0 times, 500 times, and 1500 times, the effects of whether or not cutting line, the fabric direction of the cutting area, and the number of cutting lines were investigated for tensile, shearing, compression, and mixing value of mechanical properties. The results are as follows: EM to bending times were larger in order of weft

• Geomechanics and Engineering
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• 제34권2호
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• pp.197-208
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• 2023

Rate-dependent mechanical response of sand, subjected to loading of medium to high strain rate range, is of interest for several civilian and military applications. Such rate-dependent response can vary significantly based on the initial density state of the sand, applied confining pressure, considered strain rate range, drainage condition and sand morphology. A numerical study has been carried out employing a recently proposed visco-plastic constitutive model to explore the rate-dependent mechanical behaviour of Toyoura sand under drained triaxial loading condition. The model parameters have been calibrated using the experimental data on Toyoura sand available in published literature. Under strain rates higher than a reference strain rate, the simulation results are found to be in good agreement with the experimentally observed characteristic shearing behaviour of sand, which includes increased shear strength, pronounced post-peak softening and suppressed compression. The rate-dependent response, subjected to intermediate strain rate range, has further been assessed in terms of enhancement of peak shear strength and peak friction angle over varying initial density and confining pressure. The simulation results indicate that the rate-induced strength increase is highest for the dense state and such strength enhancements remain nearly independent of the applied confinement level.

• Journal of Forest and Environmental Science
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• 제9권1호
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• pp.10-18
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• 1993

북양산(北洋産) 주요(主要) 침(針), 활엽수재(闊葉樹材)의 물리적(物理的) 성질(性質)(밀도(密屠), 만재율(晩材率), 공권율(孔圈率), 평균년수폭(平均年輸幅))과 역학적(力學的) 성질(性質)(종압축강도, 횡압축강도, 전단강도에 관하여 연구(硏究) 조사하였다. 이 실험(實驗)의 연구(硏究) 결과(結果)는 다음과 같다. 밀도(密度)와 만재율(晩材率)은 물리적(物理的) 역학적(力學的) 성질(性質)과 밀접(密接)한 관계(關係)를 나타낸 반면, 공권율(孔圈率)과 평균년수폭(平均年輸幅)은 물리적(物理的) 역학적(力學的) 성질(性質)과 거의 관계(關係)가 없음을 나타내었다.

• 한국의류학회지
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• 제8권2호
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• pp.47-57
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• 1984

Effect on the hand value and mechanical properties of blend ratio and weight had been investigated Oil summer suits for men. Relation between the mechanical properties and the deformation in behavior was also studied. The mechanical properties which influence the hand values and total hand value had been discussed and the relation between mechanical properties, hand values and fabric count had, too. As result, the following conclusions had been obtained. 1) The values of tensile properties increased with the increase of blend ratio of wool. The values of surface properties increased according to the increase of blend ratio of polyester. 2HB(bending properties) of polyester/wool blend showed higher value than that of $100\%$ wool, but there was no change in the shearing properties according to the blend ratio. The values of stiffness, crispness and anti-drape stiffness of blend fabric showed higher values than those of $100\%$ wool fabric. The value of fullness (including softness) of blend fabric showed lower value than that of $100\%$ wool fabric. 2) The correlation between hand values and mechanical properties showed following order. in stiffness : bending properties>surface properties in crispness: surface properties>bending properties in anti-drape stiffness: bending properties>surface properties>shearing properties.